## ffmpeg / libavcodec / wmaprodec.c @ c5c20ae4

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1 | 31c57185 | Sascha Sommer | ```
/*
``` |
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2 | ```
* Wmapro compatible decoder
``` |
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3 | ```
* Copyright (c) 2007 Baptiste Coudurier, Benjamin Larsson, Ulion
``` |
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4 | ```
* Copyright (c) 2008 - 2009 Sascha Sommer, Benjamin Larsson
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5 | ```
*
``` |
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6 | ```
* This file is part of FFmpeg.
``` |
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7 | ```
*
``` |
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8 | ```
* FFmpeg is free software; you can redistribute it and/or
``` |
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9 | ```
* modify it under the terms of the GNU Lesser General Public
``` |
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10 | ```
* License as published by the Free Software Foundation; either
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11 | ```
* version 2.1 of the License, or (at your option) any later version.
``` |
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12 | ```
*
``` |
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13 | ```
* FFmpeg is distributed in the hope that it will be useful,
``` |
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14 | ```
* but WITHOUT ANY WARRANTY; without even the implied warranty of
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15 | ```
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
``` |
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16 | ```
* Lesser General Public License for more details.
``` |
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17 | ```
*
``` |
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18 | ```
* You should have received a copy of the GNU Lesser General Public
``` |
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19 | ```
* License along with FFmpeg; if not, write to the Free Software
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20 | ```
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
``` |
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21 | ```
*/
``` |
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22 | |||

23 | ```
/**
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24 | ```
* @file libavcodec/wmaprodec.c
``` |
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25 | ```
* @brief wmapro decoder implementation
``` |
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26 | ```
* Wmapro is an MDCT based codec comparable to wma standard or AAC.
``` |
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27 | ```
* The decoding therefore consists of the following steps:
``` |
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28 | ```
* - bitstream decoding
``` |
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29 | ```
* - reconstruction of per-channel data
``` |
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30 | ```
* - rescaling and inverse quantization
``` |
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31 | ```
* - IMDCT
``` |
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32 | ```
* - windowing and overlapp-add
``` |
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33 | ```
*
``` |
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34 | ```
* The compressed wmapro bitstream is split into individual packets.
``` |
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35 | ```
* Every such packet contains one or more wma frames.
``` |
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36 | ```
* The compressed frames may have a variable length and frames may
``` |
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37 | ```
* cross packet boundaries.
``` |
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38 | ```
* Common to all wmapro frames is the number of samples that are stored in
``` |
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39 | ```
* a frame.
``` |
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40 | ```
* The number of samples and a few other decode flags are stored
``` |
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41 | ```
* as extradata that has to be passed to the decoder.
``` |
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42 | ```
*
``` |
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43 | ```
* The wmapro frames themselves are again split into a variable number of
``` |
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44 | ```
* subframes. Every subframe contains the data for 2^N time domain samples
``` |
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45 | ```
* where N varies between 7 and 12.
``` |
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46 | ```
*
``` |
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47 | ```
* Example wmapro bitstream (in samples):
``` |
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48 | ```
*
``` |
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49 | ```
* || packet 0 || packet 1 || packet 2 packets
``` |
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50 | ```
* ---------------------------------------------------
``` |
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51 | ```
* || frame 0 || frame 1 || frame 2 || frames
``` |
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52 | ```
* ---------------------------------------------------
``` |
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53 | ```
* || | | || | | | || || subframes of channel 0
``` |
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54 | ```
* ---------------------------------------------------
``` |
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55 | ```
* || | | || | | | || || subframes of channel 1
``` |
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56 | ```
* ---------------------------------------------------
``` |
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57 | ```
*
``` |
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58 | ```
* The frame layouts for the individual channels of a wma frame does not need
``` |
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59 | ```
* to be the same.
``` |
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60 | ```
*
``` |
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61 | ```
* However, if the offsets and lengths of several subframes of a frame are the
``` |
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62 | ```
* same, the subframes of the channels can be grouped.
``` |
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63 | ```
* Every group may then use special coding techniques like M/S stereo coding
``` |
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64 | ```
* to improve the compression ratio. These channel transformations do not
``` |
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65 | ```
* need to be applied to a whole subframe. Instead, they can also work on
``` |
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66 | ```
* individual scale factor bands (see below).
``` |
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67 | ```
* The coefficients that carry the audio signal in the frequency domain
``` |
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68 | ```
* are transmitted as huffman-coded vectors with 4, 2 and 1 elements.
``` |
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69 | ```
* In addition to that, the encoder can switch to a runlevel coding scheme
``` |
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70 | ```
* by transmitting subframe_length / 128 zero coefficients.
``` |
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71 | ```
*
``` |
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72 | ```
* Before the audio signal can be converted to the time domain, the
``` |
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73 | ```
* coefficients have to be rescaled and inverse quantized.
``` |
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74 | ```
* A subframe is therefore split into several scale factor bands that get
``` |
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75 | ```
* scaled individually.
``` |
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76 | ```
* Scale factors are submitted for every frame but they might be shared
``` |
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77 | ```
* between the subframes of a channel. Scale factors are initially DPCM-coded.
``` |
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78 | ```
* Once scale factors are shared, the differences are transmitted as runlevel
``` |
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79 | ```
* codes.
``` |
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80 | ```
* Every subframe length and offset combination in the frame layout shares a
``` |
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81 | ```
* common quantization factor that can be adjusted for every channel by a
``` |
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82 | ```
* modifier.
``` |
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83 | ```
* After the inverse quantization, the coefficients get processed by an IMDCT.
``` |
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84 | ```
* The resulting values are then windowed with a sine window and the first half
``` |
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85 | ```
* of the values are added to the second half of the output from the previous
``` |
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86 | ```
* subframe in order to reconstruct the output samples.
``` |
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87 | ```
*/
``` |
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88 | |||

89 | c1061cc7 | Sascha Sommer | #include "avcodec.h" |

90 | #include "internal.h" |
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91 | #include "get_bits.h" |
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92 | #include "put_bits.h" |
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93 | #include "wmaprodata.h" |
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94 | #include "dsputil.h" |
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95 | #include "wma.h" |
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96 | |||

97 | ```
/** current decoder limitations */
``` |
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98 | #define WMAPRO_MAX_CHANNELS 8 ///< max number of handled channels |
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99 | #define MAX_SUBFRAMES 32 ///< max number of subframes per channel |
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100 | #define MAX_BANDS 29 ///< max number of scale factor bands |
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101 | aac4b0a4 | Sascha Sommer | #define MAX_FRAMESIZE 32768 ///< maximum compressed frame size |

102 | c1061cc7 | Sascha Sommer | |

103 | #define WMAPRO_BLOCK_MAX_BITS 12 ///< log2 of max block size |
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104 | #define WMAPRO_BLOCK_MAX_SIZE (1 << WMAPRO_BLOCK_MAX_BITS) ///< maximum block size |
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105 | #define WMAPRO_BLOCK_SIZES (WMAPRO_BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1) ///< possible block sizes |
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106 | |||

107 | |||

108 | #define VLCBITS 9 |
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109 | #define SCALEVLCBITS 8 |
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110 | #define VEC4MAXDEPTH ((HUFF_VEC4_MAXBITS+VLCBITS-1)/VLCBITS) |
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111 | #define VEC2MAXDEPTH ((HUFF_VEC2_MAXBITS+VLCBITS-1)/VLCBITS) |
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112 | #define VEC1MAXDEPTH ((HUFF_VEC1_MAXBITS+VLCBITS-1)/VLCBITS) |
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113 | #define SCALEMAXDEPTH ((HUFF_SCALE_MAXBITS+SCALEVLCBITS-1)/SCALEVLCBITS) |
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114 | #define SCALERLMAXDEPTH ((HUFF_SCALE_RL_MAXBITS+VLCBITS-1)/VLCBITS) |
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115 | |||

116 | static VLC sf_vlc; ///< scale factor DPCM vlc |
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117 | static VLC sf_rl_vlc; ///< scale factor run length vlc |
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118 | static VLC vec4_vlc; ///< 4 coefficients per symbol |
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119 | static VLC vec2_vlc; ///< 2 coefficients per symbol |
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120 | static VLC vec1_vlc; ///< 1 coefficient per symbol |
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121 | static VLC coef_vlc[2]; ///< coefficient run length vlc codes |
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122 | static float sin64[33]; ///< sinus table for decorrelation |
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123 | |||

124 | ```
/**
``` |
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125 | ```
* @brief frame specific decoder context for a single channel
``` |
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126 | ```
*/
``` |
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127 | typedef struct { |
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128 | ```
int16_t prev_block_len; ///< length of the previous block
``` |
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129 | uint8_t transmit_coefs; |
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130 | uint8_t num_subframes; |
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131 | ```
uint16_t subframe_len[MAX_SUBFRAMES]; ///< subframe length in samples
``` |
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132 | ```
uint16_t subframe_offset[MAX_SUBFRAMES]; ///< subframe positions in the current frame
``` |
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133 | ```
uint8_t cur_subframe; ///< current subframe number
``` |
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134 | ```
uint16_t decoded_samples; ///< number of already processed samples
``` |
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135 | ```
uint8_t grouped; ///< channel is part of a group
``` |
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136 | int quant_step; ///< quantization step for the current subframe |
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137 | ```
int8_t reuse_sf; ///< share scale factors between subframes
``` |
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138 | ```
int8_t scale_factor_step; ///< scaling step for the current subframe
``` |
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139 | int max_scale_factor; ///< maximum scale factor for the current subframe |
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140 | 7dca334d | Sascha Sommer | int saved_scale_factors[2][MAX_BANDS]; ///< resampled and (previously) transmitted scale factor values |

141 | ```
int8_t scale_factor_idx; ///< index for the transmitted scale factor values (used for resampling)
``` |
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142 | int* scale_factors; ///< pointer to the scale factor values used for decoding |
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143 | c1061cc7 | Sascha Sommer | ```
uint8_t table_idx; ///< index in sf_offsets for the scale factor reference block
``` |

144 | float* coeffs; ///< pointer to the subframe decode buffer |
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145 | 84dc2d8a | Måns Rullgård | DECLARE_ALIGNED(16, float, out)[WMAPRO_BLOCK_MAX_SIZE + WMAPRO_BLOCK_MAX_SIZE / 2]; ///< output buffer |

146 | c1061cc7 | Sascha Sommer | } WMAProChannelCtx; |

147 | |||

148 | ```
/**
``` |
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149 | ```
* @brief channel group for channel transformations
``` |
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150 | ```
*/
``` |
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151 | typedef struct { |
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152 | ```
uint8_t num_channels; ///< number of channels in the group
``` |
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153 | ```
int8_t transform; ///< transform on / off
``` |
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154 | ```
int8_t transform_band[MAX_BANDS]; ///< controls if the transform is enabled for a certain band
``` |
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155 | ```
float decorrelation_matrix[WMAPRO_MAX_CHANNELS*WMAPRO_MAX_CHANNELS];
``` |
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156 | float* channel_data[WMAPRO_MAX_CHANNELS]; ///< transformation coefficients |
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157 | } WMAProChannelGrp; |
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158 | |||

159 | ```
/**
``` |
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160 | ```
* @brief main decoder context
``` |
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161 | ```
*/
``` |
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162 | typedef struct WMAProDecodeCtx { |
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163 | ```
/* generic decoder variables */
``` |
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164 | ```
AVCodecContext* avctx; ///< codec context for av_log
``` |
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165 | ```
DSPContext dsp; ///< accelerated DSP functions
``` |
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166 | uint8_t frame_data[MAX_FRAMESIZE + |
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167 | ```
FF_INPUT_BUFFER_PADDING_SIZE];///< compressed frame data
``` |
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168 | ```
PutBitContext pb; ///< context for filling the frame_data buffer
``` |
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169 | 01b22147 | Måns Rullgård | ```
FFTContext mdct_ctx[WMAPRO_BLOCK_SIZES]; ///< MDCT context per block size
``` |

170 | 84dc2d8a | Måns Rullgård | DECLARE_ALIGNED(16, float, tmp)[WMAPRO_BLOCK_MAX_SIZE]; ///< IMDCT output buffer |

171 | c1061cc7 | Sascha Sommer | float* windows[WMAPRO_BLOCK_SIZES]; ///< windows for the different block sizes |

172 | |||

173 | ```
/* frame size dependent frame information (set during initialization) */
``` |
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174 | ```
uint32_t decode_flags; ///< used compression features
``` |
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175 | ```
uint8_t len_prefix; ///< frame is prefixed with its length
``` |
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176 | ```
uint8_t dynamic_range_compression; ///< frame contains DRC data
``` |
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177 | ```
uint8_t bits_per_sample; ///< integer audio sample size for the unscaled IMDCT output (used to scale to [-1.0, 1.0])
``` |
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178 | ```
uint16_t samples_per_frame; ///< number of samples to output
``` |
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179 | uint16_t log2_frame_size; |
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180 | ```
int8_t num_channels; ///< number of channels in the stream (same as AVCodecContext.num_channels)
``` |
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181 | ```
int8_t lfe_channel; ///< lfe channel index
``` |
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182 | uint8_t max_num_subframes; |
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183 | ```
uint8_t subframe_len_bits; ///< number of bits used for the subframe length
``` |
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184 | ```
uint8_t max_subframe_len_bit; ///< flag indicating that the subframe is of maximum size when the first subframe length bit is 1
``` |
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185 | uint16_t min_samples_per_subframe; |
||

186 | ```
int8_t num_sfb[WMAPRO_BLOCK_SIZES]; ///< scale factor bands per block size
``` |
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187 | ```
int16_t sfb_offsets[WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor band offsets (multiples of 4)
``` |
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188 | ```
int8_t sf_offsets[WMAPRO_BLOCK_SIZES][WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor resample matrix
``` |
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189 | ```
int16_t subwoofer_cutoffs[WMAPRO_BLOCK_SIZES]; ///< subwoofer cutoff values
``` |
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190 | |||

191 | ```
/* packet decode state */
``` |
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192 | 20169324 | Sascha Sommer | ```
GetBitContext pgb; ///< bitstream reader context for the packet
``` |

193 | bc7f96b1 | Sascha Sommer | ```
uint8_t packet_offset; ///< frame offset in the packet
``` |

194 | c1061cc7 | Sascha Sommer | ```
uint8_t packet_sequence_number; ///< current packet number
``` |

195 | int num_saved_bits; ///< saved number of bits |
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196 | int frame_offset; ///< frame offset in the bit reservoir |
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197 | int subframe_offset; ///< subframe offset in the bit reservoir |
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198 | ```
uint8_t packet_loss; ///< set in case of bitstream error
``` |
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199 | 5f28b5e7 | Sascha Sommer | ```
uint8_t packet_done; ///< set when a packet is fully decoded
``` |

200 | c1061cc7 | Sascha Sommer | |

201 | ```
/* frame decode state */
``` |
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202 | ```
uint32_t frame_num; ///< current frame number (not used for decoding)
``` |
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203 | ```
GetBitContext gb; ///< bitstream reader context
``` |
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204 | int buf_bit_size; ///< buffer size in bits |
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205 | float* samples; ///< current samplebuffer pointer |
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206 | float* samples_end; ///< maximum samplebuffer pointer |
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207 | ```
uint8_t drc_gain; ///< gain for the DRC tool
``` |
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208 | ```
int8_t skip_frame; ///< skip output step
``` |
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209 | ```
int8_t parsed_all_subframes; ///< all subframes decoded?
``` |
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210 | |||

211 | ```
/* subframe/block decode state */
``` |
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212 | ```
int16_t subframe_len; ///< current subframe length
``` |
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213 | ```
int8_t channels_for_cur_subframe; ///< number of channels that contain the subframe
``` |
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214 | int8_t channel_indexes_for_cur_subframe[WMAPRO_MAX_CHANNELS]; |
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215 | ```
int8_t num_bands; ///< number of scale factor bands
``` |
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216 | ```
int16_t* cur_sfb_offsets; ///< sfb offsets for the current block
``` |
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217 | ```
uint8_t table_idx; ///< index for the num_sfb, sfb_offsets, sf_offsets and subwoofer_cutoffs tables
``` |
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218 | ```
int8_t esc_len; ///< length of escaped coefficients
``` |
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219 | |||

220 | ```
uint8_t num_chgroups; ///< number of channel groups
``` |
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221 | ```
WMAProChannelGrp chgroup[WMAPRO_MAX_CHANNELS]; ///< channel group information
``` |
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222 | |||

223 | ```
WMAProChannelCtx channel[WMAPRO_MAX_CHANNELS]; ///< per channel data
``` |
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224 | } WMAProDecodeCtx; |
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225 | |||

226 | |||

227 | ```
/**
``` |
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228 | ```
*@brief helper function to print the most important members of the context
``` |
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229 | ```
*@param s context
``` |
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230 | ```
*/
``` |
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231 | static void av_cold dump_context(WMAProDecodeCtx *s) |
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232 | { |
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233 | #define PRINT(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %d\n", a, b); |
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234 | #define PRINT_HEX(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %x\n", a, b); |
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235 | |||

236 | ```
PRINT("ed sample bit depth", s->bits_per_sample);
``` |
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237 | ```
PRINT_HEX("ed decode flags", s->decode_flags);
``` |
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238 | ```
PRINT("samples per frame", s->samples_per_frame);
``` |
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239 | ```
PRINT("log2 frame size", s->log2_frame_size);
``` |
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240 | ```
PRINT("max num subframes", s->max_num_subframes);
``` |
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241 | ```
PRINT("len prefix", s->len_prefix);
``` |
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242 | ```
PRINT("num channels", s->num_channels);
``` |
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243 | } |
||

244 | |||

245 | da136c7e | Sascha Sommer | ```
/**
``` |

246 | ```
*@brief Uninitialize the decoder and free all resources.
``` |
||

247 | ```
*@param avctx codec context
``` |
||

248 | ```
*@return 0 on success, < 0 otherwise
``` |
||

249 | ```
*/
``` |
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250 | static av_cold int decode_end(AVCodecContext *avctx) |
||

251 | { |
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252 | c1061cc7 | Sascha Sommer | WMAProDecodeCtx *s = avctx->priv_data; |

253 | da136c7e | Sascha Sommer | ```
int i;
``` |

254 | |||

255 | b979e4a2 | Diego Biurrun | for (i = 0; i < WMAPRO_BLOCK_SIZES; i++) |

256 | da136c7e | Sascha Sommer | ff_mdct_end(&s->mdct_ctx[i]); |

257 | |||

258 | return 0; |
||

259 | } |
||

260 | |||

261 | ```
/**
``` |
||

262 | c1061cc7 | Sascha Sommer | ```
*@brief Initialize the decoder.
``` |

263 | ```
*@param avctx codec context
``` |
||

264 | ```
*@return 0 on success, -1 otherwise
``` |
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265 | ```
*/
``` |
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266 | static av_cold int decode_init(AVCodecContext *avctx) |
||

267 | { |
||

268 | WMAProDecodeCtx *s = avctx->priv_data; |
||

269 | e0b1d660 | Diego Biurrun | uint8_t *edata_ptr = avctx->extradata; |

270 | c1061cc7 | Sascha Sommer | unsigned int channel_mask; |

271 | ```
int i;
``` |
||

272 | ```
int log2_max_num_subframes;
``` |
||

273 | ```
int num_possible_block_sizes;
``` |
||

274 | |||

275 | s->avctx = avctx; |
||

276 | dsputil_init(&s->dsp, avctx); |
||

277 | init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE); |
||

278 | |||

279 | avctx->sample_fmt = SAMPLE_FMT_FLT; |
||

280 | |||

281 | if (avctx->extradata_size >= 18) { |
||

282 | ```
s->decode_flags = AV_RL16(edata_ptr+14);
``` |
||

283 | ```
channel_mask = AV_RL32(edata_ptr+2);
``` |
||

284 | s->bits_per_sample = AV_RL16(edata_ptr); |
||

285 | ```
/** dump the extradata */
``` |
||

286 | for (i = 0; i < avctx->extradata_size; i++) |
||

287 | ```
dprintf(avctx, "[%x] ", avctx->extradata[i]);
``` |
||

288 | ```
dprintf(avctx, "\n");
``` |
||

289 | |||

290 | ```
} else {
``` |
||

291 | ```
av_log_ask_for_sample(avctx, "Unknown extradata size\n");
``` |
||

292 | ```
return AVERROR_INVALIDDATA;
``` |
||

293 | } |
||

294 | |||

295 | ```
/** generic init */
``` |
||

296 | ```
s->log2_frame_size = av_log2(avctx->block_align) + 4;
``` |
||

297 | |||

298 | ```
/** frame info */
``` |
||

299 | s->skip_frame = 1; /** skip first frame */ |
||

300 | ```
s->packet_loss = 1;
``` |
||

301 | ```
s->len_prefix = (s->decode_flags & 0x40);
``` |
||

302 | |||

303 | ```
if (!s->len_prefix) {
``` |
||

304 | ```
av_log_ask_for_sample(avctx, "no length prefix\n");
``` |
||

305 | ```
return AVERROR_INVALIDDATA;
``` |
||

306 | } |
||

307 | |||

308 | ```
/** get frame len */
``` |
||

309 | ```
s->samples_per_frame = 1 << ff_wma_get_frame_len_bits(avctx->sample_rate,
``` |
||

310 | ```
3, s->decode_flags);
``` |
||

311 | |||

312 | ```
/** init previous block len */
``` |
||

313 | for (i = 0; i < avctx->channels; i++) |
||

314 | s->channel[i].prev_block_len = s->samples_per_frame; |
||

315 | |||

316 | ```
/** subframe info */
``` |
||

317 | log2_max_num_subframes = ((s->decode_flags & 0x38) >> 3); |
||

318 | ```
s->max_num_subframes = 1 << log2_max_num_subframes;
``` |
||

319 | if (s->max_num_subframes == 16) |
||

320 | ```
s->max_subframe_len_bit = 1;
``` |
||

321 | ```
s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
``` |
||

322 | |||

323 | ```
num_possible_block_sizes = log2_max_num_subframes + 1;
``` |
||

324 | s->min_samples_per_subframe = s->samples_per_frame / s->max_num_subframes; |
||

325 | ```
s->dynamic_range_compression = (s->decode_flags & 0x80);
``` |
||

326 | |||

327 | ```
if (s->max_num_subframes > MAX_SUBFRAMES) {
``` |
||

328 | ```
av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %i\n",
``` |
||

329 | s->max_num_subframes); |
||

330 | ```
return AVERROR_INVALIDDATA;
``` |
||

331 | } |
||

332 | |||

333 | s->num_channels = avctx->channels; |
||

334 | |||

335 | ```
/** extract lfe channel position */
``` |
||

336 | ```
s->lfe_channel = -1;
``` |
||

337 | |||

338 | if (channel_mask & 8) { |
||

339 | unsigned int mask; |
||

340 | for (mask = 1; mask < 16; mask <<= 1) { |
||

341 | ```
if (channel_mask & mask)
``` |
||

342 | ++s->lfe_channel; |
||

343 | } |
||

344 | } |
||

345 | |||

346 | c5c20ae4 | Stefano Sabatini | if (s->num_channels < 0) { |

347 | ```
av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n", s->num_channels);
``` |
||

348 | ```
return AVERROR_INVALIDDATA;
``` |
||

349 | } else if (s->num_channels > WMAPRO_MAX_CHANNELS) { |
||

350 | ```
av_log_ask_for_sample(avctx, "unsupported number of channels\n");
``` |
||

351 | ```
return AVERROR_PATCHWELCOME;
``` |
||

352 | c1061cc7 | Sascha Sommer | } |

353 | |||

354 | INIT_VLC_STATIC(&sf_vlc, SCALEVLCBITS, HUFF_SCALE_SIZE, |
||

355 | scale_huffbits, 1, 1, |
||

356 | scale_huffcodes, 2, 2, 616); |
||

357 | |||

358 | INIT_VLC_STATIC(&sf_rl_vlc, VLCBITS, HUFF_SCALE_RL_SIZE, |
||

359 | scale_rl_huffbits, 1, 1, |
||

360 | scale_rl_huffcodes, 4, 4, 1406); |
||

361 | |||

362 | ```
INIT_VLC_STATIC(&coef_vlc[0], VLCBITS, HUFF_COEF0_SIZE,
``` |
||

363 | coef0_huffbits, 1, 1, |
||

364 | coef0_huffcodes, 4, 4, 2108); |
||

365 | |||

366 | ```
INIT_VLC_STATIC(&coef_vlc[1], VLCBITS, HUFF_COEF1_SIZE,
``` |
||

367 | coef1_huffbits, 1, 1, |
||

368 | coef1_huffcodes, 4, 4, 3912); |
||

369 | |||

370 | INIT_VLC_STATIC(&vec4_vlc, VLCBITS, HUFF_VEC4_SIZE, |
||

371 | vec4_huffbits, 1, 1, |
||

372 | vec4_huffcodes, 2, 2, 604); |
||

373 | |||

374 | INIT_VLC_STATIC(&vec2_vlc, VLCBITS, HUFF_VEC2_SIZE, |
||

375 | vec2_huffbits, 1, 1, |
||

376 | vec2_huffcodes, 2, 2, 562); |
||

377 | |||

378 | INIT_VLC_STATIC(&vec1_vlc, VLCBITS, HUFF_VEC1_SIZE, |
||

379 | vec1_huffbits, 1, 1, |
||

380 | vec1_huffcodes, 2, 2, 562); |
||

381 | |||

382 | ```
/** calculate number of scale factor bands and their offsets
``` |
||

383 | ```
for every possible block size */
``` |
||

384 | for (i = 0; i < num_possible_block_sizes; i++) { |
||

385 | ```
int subframe_len = s->samples_per_frame >> i;
``` |
||

386 | ```
int x;
``` |
||

387 | int band = 1; |
||

388 | |||

389 | s->sfb_offsets[i][0] = 0; |
||

390 | |||

391 | e0b1d660 | Diego Biurrun | for (x = 0; x < MAX_BANDS-1 && s->sfb_offsets[i][band - 1] < subframe_len; x++) { |

392 | c1061cc7 | Sascha Sommer | int offset = (subframe_len * 2 * critical_freq[x]) |

393 | ```
/ s->avctx->sample_rate + 2;
``` |
||

394 | ```
offset &= ~3;
``` |
||

395 | e0b1d660 | Diego Biurrun | if (offset > s->sfb_offsets[i][band - 1]) |

396 | c1061cc7 | Sascha Sommer | s->sfb_offsets[i][band++] = offset; |

397 | } |
||

398 | ```
s->sfb_offsets[i][band - 1] = subframe_len;
``` |
||

399 | ```
s->num_sfb[i] = band - 1;
``` |
||

400 | } |
||

401 | |||

402 | |||

403 | ```
/** Scale factors can be shared between blocks of different size
``` |
||

404 | ```
as every block has a different scale factor band layout.
``` |
||

405 | ```
The matrix sf_offsets is needed to find the correct scale factor.
``` |
||

406 | ```
*/
``` |
||

407 | |||

408 | for (i = 0; i < num_possible_block_sizes; i++) { |
||

409 | ```
int b;
``` |
||

410 | for (b = 0; b < s->num_sfb[i]; b++) { |
||

411 | ```
int x;
``` |
||

412 | ```
int offset = ((s->sfb_offsets[i][b]
``` |
||

413 | e0b1d660 | Diego Biurrun | + s->sfb_offsets[i][b + 1] - 1) << i) >> 1; |

414 | c1061cc7 | Sascha Sommer | for (x = 0; x < num_possible_block_sizes; x++) { |

415 | int v = 0; |
||

416 | while (s->sfb_offsets[x][v + 1] << x < offset) |
||

417 | ++v; |
||

418 | s->sf_offsets[i][x][b] = v; |
||

419 | } |
||

420 | } |
||

421 | } |
||

422 | |||

423 | ```
/** init MDCT, FIXME: only init needed sizes */
``` |
||

424 | for (i = 0; i < WMAPRO_BLOCK_SIZES; i++) |
||

425 | ff_mdct_init(&s->mdct_ctx[i], BLOCK_MIN_BITS+1+i, 1, |
||

426 | e0b1d660 | Diego Biurrun | 1.0 / (1 << (BLOCK_MIN_BITS + i - 1)) |

427 | c1061cc7 | Sascha Sommer | / (1 << (s->bits_per_sample - 1))); |

428 | |||

429 | ```
/** init MDCT windows: simple sinus window */
``` |
||

430 | for (i = 0; i < WMAPRO_BLOCK_SIZES; i++) { |
||

431 | 6776061b | Vitor Sessak | const int win_idx = WMAPRO_BLOCK_MAX_BITS - i; |

432 | 14b86070 | Reimar Döffinger | ff_init_ff_sine_windows(win_idx); |

433 | e0b1d660 | Diego Biurrun | ```
s->windows[WMAPRO_BLOCK_SIZES - i - 1] = ff_sine_windows[win_idx];
``` |

434 | c1061cc7 | Sascha Sommer | } |

435 | |||

436 | ```
/** calculate subwoofer cutoff values */
``` |
||

437 | for (i = 0; i < num_possible_block_sizes; i++) { |
||

438 | ```
int block_size = s->samples_per_frame >> i;
``` |
||

439 | int cutoff = (440*block_size + 3 * (s->avctx->sample_rate >> 1) - 1) |
||

440 | / s->avctx->sample_rate; |
||

441 | ```
s->subwoofer_cutoffs[i] = av_clip(cutoff, 4, block_size);
``` |
||

442 | } |
||

443 | |||

444 | ```
/** calculate sine values for the decorrelation matrix */
``` |
||

445 | for (i = 0; i < 33; i++) |
||

446 | sin64[i] = sin(i*M_PI / 64.0); |
||

447 | |||

448 | ```
if (avctx->debug & FF_DEBUG_BITSTREAM)
``` |
||

449 | dump_context(s); |
||

450 | |||

451 | avctx->channel_layout = channel_mask; |
||

452 | return 0; |
||

453 | } |
||

454 | |||

455 | ```
/**
``` |
||

456 | ```
*@brief Decode the subframe length.
``` |
||

457 | ```
*@param s context
``` |
||

458 | ```
*@param offset sample offset in the frame
``` |
||

459 | ```
*@return decoded subframe length on success, < 0 in case of an error
``` |
||

460 | ```
*/
``` |
||

461 | static int decode_subframe_length(WMAProDecodeCtx *s, int offset) |
||

462 | { |
||

463 | int frame_len_shift = 0; |
||

464 | ```
int subframe_len;
``` |
||

465 | |||

466 | ```
/** no need to read from the bitstream when only one length is possible */
``` |
||

467 | ```
if (offset == s->samples_per_frame - s->min_samples_per_subframe)
``` |
||

468 | ```
return s->min_samples_per_subframe;
``` |
||

469 | |||

470 | ```
/** 1 bit indicates if the subframe is of maximum length */
``` |
||

471 | ```
if (s->max_subframe_len_bit) {
``` |
||

472 | ```
if (get_bits1(&s->gb))
``` |
||

473 | frame_len_shift = 1 + get_bits(&s->gb, s->subframe_len_bits-1); |
||

474 | ```
} else
``` |
||

475 | frame_len_shift = get_bits(&s->gb, s->subframe_len_bits); |
||

476 | |||

477 | subframe_len = s->samples_per_frame >> frame_len_shift; |
||

478 | |||

479 | ```
/** sanity check the length */
``` |
||

480 | e0b1d660 | Diego Biurrun | ```
if (subframe_len < s->min_samples_per_subframe ||
``` |

481 | subframe_len > s->samples_per_frame) { |
||

482 | c1061cc7 | Sascha Sommer | ```
av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
``` |

483 | subframe_len); |
||

484 | ```
return AVERROR_INVALIDDATA;
``` |
||

485 | } |
||

486 | ```
return subframe_len;
``` |
||

487 | } |
||

488 | |||

489 | ```
/**
``` |
||

490 | ```
*@brief Decode how the data in the frame is split into subframes.
``` |
||

491 | ```
* Every WMA frame contains the encoded data for a fixed number of
``` |
||

492 | ```
* samples per channel. The data for every channel might be split
``` |
||

493 | ```
* into several subframes. This function will reconstruct the list of
``` |
||

494 | ```
* subframes for every channel.
``` |
||

495 | ```
*
``` |
||

496 | ```
* If the subframes are not evenly split, the algorithm estimates the
``` |
||

497 | ```
* channels with the lowest number of total samples.
``` |
||

498 | ```
* Afterwards, for each of these channels a bit is read from the
``` |
||

499 | ```
* bitstream that indicates if the channel contains a subframe with the
``` |
||

500 | ```
* next subframe size that is going to be read from the bitstream or not.
``` |
||

501 | ```
* If a channel contains such a subframe, the subframe size gets added to
``` |
||

502 | ```
* the channel's subframe list.
``` |
||

503 | ```
* The algorithm repeats these steps until the frame is properly divided
``` |
||

504 | ```
* between the individual channels.
``` |
||

505 | ```
*
``` |
||

506 | ```
*@param s context
``` |
||

507 | ```
*@return 0 on success, < 0 in case of an error
``` |
||

508 | ```
*/
``` |
||

509 | static int decode_tilehdr(WMAProDecodeCtx *s) |
||

510 | { |
||

511 | ```
uint16_t num_samples[WMAPRO_MAX_CHANNELS]; /** sum of samples for all currently known subframes of a channel */
``` |
||

512 | ```
uint8_t contains_subframe[WMAPRO_MAX_CHANNELS]; /** flag indicating if a channel contains the current subframe */
``` |
||

513 | int channels_for_cur_subframe = s->num_channels; /** number of channels that contain the current subframe */ |
||

514 | int fixed_channel_layout = 0; /** flag indicating that all channels use the same subframe offsets and sizes */ |
||

515 | int min_channel_len = 0; /** smallest sum of samples (channels with this length will be processed first) */ |
||

516 | ```
int c;
``` |
||

517 | |||

518 | ```
/* Should never consume more than 3073 bits (256 iterations for the
``` |
||

519 | ```
* while loop when always the minimum amount of 128 samples is substracted
``` |
||

520 | ```
* from missing samples in the 8 channel case).
``` |
||

521 | ```
* 1 + BLOCK_MAX_SIZE * MAX_CHANNELS / BLOCK_MIN_SIZE * (MAX_CHANNELS + 4)
``` |
||

522 | ```
*/
``` |
||

523 | |||

524 | ```
/** reset tiling information */
``` |
||

525 | for (c = 0; c < s->num_channels; c++) |
||

526 | ```
s->channel[c].num_subframes = 0;
``` |
||

527 | |||

528 | memset(num_samples, 0, sizeof(num_samples)); |
||

529 | |||

530 | if (s->max_num_subframes == 1 || get_bits1(&s->gb)) |
||

531 | ```
fixed_channel_layout = 1;
``` |
||

532 | |||

533 | ```
/** loop until the frame data is split between the subframes */
``` |
||

534 | ```
do {
``` |
||

535 | ```
int subframe_len;
``` |
||

536 | |||

537 | ```
/** check which channels contain the subframe */
``` |
||

538 | for (c = 0; c < s->num_channels; c++) { |
||

539 | ```
if (num_samples[c] == min_channel_len) {
``` |
||

540 | if (fixed_channel_layout || channels_for_cur_subframe == 1 || |
||

541 | (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe)) |
||

542 | ```
contains_subframe[c] = 1;
``` |
||

543 | ```
else
``` |
||

544 | contains_subframe[c] = get_bits1(&s->gb); |
||

545 | ```
} else
``` |
||

546 | ```
contains_subframe[c] = 0;
``` |
||

547 | } |
||

548 | |||

549 | ```
/** get subframe length, subframe_len == 0 is not allowed */
``` |
||

550 | if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0) |
||

551 | ```
return AVERROR_INVALIDDATA;
``` |
||

552 | |||

553 | ```
/** add subframes to the individual channels and find new min_channel_len */
``` |
||

554 | min_channel_len += subframe_len; |
||

555 | for (c = 0; c < s->num_channels; c++) { |
||

556 | WMAProChannelCtx* chan = &s->channel[c]; |
||

557 | |||

558 | ```
if (contains_subframe[c]) {
``` |
||

559 | ```
if (chan->num_subframes >= MAX_SUBFRAMES) {
``` |
||

560 | av_log(s->avctx, AV_LOG_ERROR, |
||

561 | ```
"broken frame: num subframes > 31\n");
``` |
||

562 | ```
return AVERROR_INVALIDDATA;
``` |
||

563 | } |
||

564 | chan->subframe_len[chan->num_subframes] = subframe_len; |
||

565 | num_samples[c] += subframe_len; |
||

566 | ++chan->num_subframes; |
||

567 | ```
if (num_samples[c] > s->samples_per_frame) {
``` |
||

568 | e0b1d660 | Diego Biurrun | ```
av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
``` |

569 | c1061cc7 | Sascha Sommer | ```
"channel len > samples_per_frame\n");
``` |

570 | ```
return AVERROR_INVALIDDATA;
``` |
||

571 | } |
||

572 | e0b1d660 | Diego Biurrun | } else if (num_samples[c] <= min_channel_len) { |

573 | c1061cc7 | Sascha Sommer | ```
if (num_samples[c] < min_channel_len) {
``` |

574 | ```
channels_for_cur_subframe = 0;
``` |
||

575 | min_channel_len = num_samples[c]; |
||

576 | } |
||

577 | ++channels_for_cur_subframe; |
||

578 | } |
||

579 | } |
||

580 | ```
} while (min_channel_len < s->samples_per_frame);
``` |
||

581 | |||

582 | for (c = 0; c < s->num_channels; c++) { |
||

583 | ```
int i;
``` |
||

584 | int offset = 0; |
||

585 | for (i = 0; i < s->channel[c].num_subframes; i++) { |
||

586 | ```
dprintf(s->avctx, "frame[%i] channel[%i] subframe[%i]"
``` |
||

587 | e0b1d660 | Diego Biurrun | ```
" len %i\n", s->frame_num, c, i,
``` |

588 | s->channel[c].subframe_len[i]); |
||

589 | c1061cc7 | Sascha Sommer | s->channel[c].subframe_offset[i] = offset; |

590 | offset += s->channel[c].subframe_len[i]; |
||

591 | } |
||

592 | } |
||

593 | |||

594 | return 0; |
||

595 | } |
||

596 | |||

597 | ```
/**
``` |
||

598 | da136c7e | Sascha Sommer | ```
*@brief Calculate a decorrelation matrix from the bitstream parameters.
``` |

599 | ```
*@param s codec context
``` |
||

600 | ```
*@param chgroup channel group for which the matrix needs to be calculated
``` |
||

601 | ```
*/
``` |
||

602 | c1061cc7 | Sascha Sommer | static void decode_decorrelation_matrix(WMAProDecodeCtx *s, |

603 | WMAProChannelGrp *chgroup) |
||

604 | da136c7e | Sascha Sommer | { |

605 | ```
int i;
``` |
||

606 | int offset = 0; |
||

607 | int8_t rotation_offset[WMAPRO_MAX_CHANNELS * WMAPRO_MAX_CHANNELS]; |
||

608 | c1061cc7 | Sascha Sommer | ```
memset(chgroup->decorrelation_matrix, 0, s->num_channels *
``` |

609 | ```
s->num_channels * sizeof(*chgroup->decorrelation_matrix));
``` |
||

610 | da136c7e | Sascha Sommer | |

611 | b25a8818 | Diego Biurrun | for (i = 0; i < chgroup->num_channels * (chgroup->num_channels - 1) >> 1; i++) |

612 | b979e4a2 | Diego Biurrun | ```
rotation_offset[i] = get_bits(&s->gb, 6);
``` |

613 | da136c7e | Sascha Sommer | |

614 | b25a8818 | Diego Biurrun | for (i = 0; i < chgroup->num_channels; i++) |

615 | da136c7e | Sascha Sommer | chgroup->decorrelation_matrix[chgroup->num_channels * i + i] = |

616 | e0b1d660 | Diego Biurrun | get_bits1(&s->gb) ? 1.0 : -1.0; |

617 | da136c7e | Sascha Sommer | |

618 | b25a8818 | Diego Biurrun | for (i = 1; i < chgroup->num_channels; i++) { |

619 | da136c7e | Sascha Sommer | ```
int x;
``` |

620 | b25a8818 | Diego Biurrun | for (x = 0; x < i; x++) { |

621 | da136c7e | Sascha Sommer | ```
int y;
``` |

622 | b979e4a2 | Diego Biurrun | for (y = 0; y < i + 1; y++) { |

623 | da136c7e | Sascha Sommer | ```
float v1 = chgroup->decorrelation_matrix[x * chgroup->num_channels + y];
``` |

624 | ```
float v2 = chgroup->decorrelation_matrix[i * chgroup->num_channels + y];
``` |
||

625 | ```
int n = rotation_offset[offset + x];
``` |
||

626 | ```
float sinv;
``` |
||

627 | ```
float cosv;
``` |
||

628 | |||

629 | b25a8818 | Diego Biurrun | if (n < 32) { |

630 | da136c7e | Sascha Sommer | sinv = sin64[n]; |

631 | e0b1d660 | Diego Biurrun | ```
cosv = sin64[32 - n];
``` |

632 | da136c7e | Sascha Sommer | ```
} else {
``` |

633 | e0b1d660 | Diego Biurrun | ```
sinv = sin64[64 - n];
``` |

634 | ```
cosv = -sin64[n - 32];
``` |
||

635 | da136c7e | Sascha Sommer | } |

636 | |||

637 | chgroup->decorrelation_matrix[y + x * chgroup->num_channels] = |
||

638 | (v1 * sinv) - (v2 * cosv); |
||

639 | chgroup->decorrelation_matrix[y + i * chgroup->num_channels] = |
||

640 | (v1 * cosv) + (v2 * sinv); |
||

641 | } |
||

642 | } |
||

643 | offset += i; |
||

644 | } |
||

645 | } |
||

646 | |||

647 | ```
/**
``` |
||

648 | c1061cc7 | Sascha Sommer | ```
*@brief Decode channel transformation parameters
``` |

649 | ```
*@param s codec context
``` |
||

650 | ```
*@return 0 in case of success, < 0 in case of bitstream errors
``` |
||

651 | ```
*/
``` |
||

652 | static int decode_channel_transform(WMAProDecodeCtx* s) |
||

653 | { |
||

654 | ```
int i;
``` |
||

655 | ```
/* should never consume more than 1921 bits for the 8 channel case
``` |
||

656 | e0b1d660 | Diego Biurrun | ```
* 1 + MAX_CHANNELS * (MAX_CHANNELS + 2 + 3 * MAX_CHANNELS * MAX_CHANNELS
``` |

657 | c1061cc7 | Sascha Sommer | ```
* + MAX_CHANNELS + MAX_BANDS + 1)
``` |

658 | ```
*/
``` |
||

659 | |||

660 | ```
/** in the one channel case channel transforms are pointless */
``` |
||

661 | ```
s->num_chgroups = 0;
``` |
||

662 | if (s->num_channels > 1) { |
||

663 | ```
int remaining_channels = s->channels_for_cur_subframe;
``` |
||

664 | |||

665 | ```
if (get_bits1(&s->gb)) {
``` |
||

666 | av_log_ask_for_sample(s->avctx, |
||

667 | ```
"unsupported channel transform bit\n");
``` |
||

668 | ```
return AVERROR_INVALIDDATA;
``` |
||

669 | } |
||

670 | |||

671 | for (s->num_chgroups = 0; remaining_channels && |
||

672 | e0b1d660 | Diego Biurrun | s->num_chgroups < s->channels_for_cur_subframe; s->num_chgroups++) { |

673 | c1061cc7 | Sascha Sommer | WMAProChannelGrp* chgroup = &s->chgroup[s->num_chgroups]; |

674 | ```
float** channel_data = chgroup->channel_data;
``` |
||

675 | ```
chgroup->num_channels = 0;
``` |
||

676 | ```
chgroup->transform = 0;
``` |
||

677 | |||

678 | ```
/** decode channel mask */
``` |
||

679 | if (remaining_channels > 2) { |
||

680 | for (i = 0; i < s->channels_for_cur_subframe; i++) { |
||

681 | ```
int channel_idx = s->channel_indexes_for_cur_subframe[i];
``` |
||

682 | ```
if (!s->channel[channel_idx].grouped
``` |
||

683 | && get_bits1(&s->gb)) { |
||

684 | ++chgroup->num_channels; |
||

685 | ```
s->channel[channel_idx].grouped = 1;
``` |
||

686 | *channel_data++ = s->channel[channel_idx].coeffs; |
||

687 | } |
||

688 | } |
||

689 | ```
} else {
``` |
||

690 | chgroup->num_channels = remaining_channels; |
||

691 | for (i = 0; i < s->channels_for_cur_subframe; i++) { |
||

692 | ```
int channel_idx = s->channel_indexes_for_cur_subframe[i];
``` |
||

693 | ```
if (!s->channel[channel_idx].grouped)
``` |
||

694 | *channel_data++ = s->channel[channel_idx].coeffs; |
||

695 | ```
s->channel[channel_idx].grouped = 1;
``` |
||

696 | } |
||

697 | } |
||

698 | |||

699 | ```
/** decode transform type */
``` |
||

700 | if (chgroup->num_channels == 2) { |
||

701 | ```
if (get_bits1(&s->gb)) {
``` |
||

702 | ```
if (get_bits1(&s->gb)) {
``` |
||

703 | av_log_ask_for_sample(s->avctx, |
||

704 | e0b1d660 | Diego Biurrun | ```
"unsupported channel transform type\n");
``` |

705 | c1061cc7 | Sascha Sommer | } |

706 | ```
} else {
``` |
||

707 | ```
chgroup->transform = 1;
``` |
||

708 | if (s->num_channels == 2) { |
||

709 | chgroup->decorrelation_matrix[0] = 1.0; |
||

710 | chgroup->decorrelation_matrix[1] = -1.0; |
||

711 | chgroup->decorrelation_matrix[2] = 1.0; |
||

712 | chgroup->decorrelation_matrix[3] = 1.0; |
||

713 | ```
} else {
``` |
||

714 | ```
/** cos(pi/4) */
``` |
||

715 | chgroup->decorrelation_matrix[0] = 0.70703125; |
||

716 | chgroup->decorrelation_matrix[1] = -0.70703125; |
||

717 | chgroup->decorrelation_matrix[2] = 0.70703125; |
||

718 | chgroup->decorrelation_matrix[3] = 0.70703125; |
||

719 | } |
||

720 | } |
||

721 | } else if (chgroup->num_channels > 2) { |
||

722 | ```
if (get_bits1(&s->gb)) {
``` |
||

723 | ```
chgroup->transform = 1;
``` |
||

724 | ```
if (get_bits1(&s->gb)) {
``` |
||

725 | decode_decorrelation_matrix(s, chgroup); |
||

726 | ```
} else {
``` |
||

727 | ```
/** FIXME: more than 6 coupled channels not supported */
``` |
||

728 | if (chgroup->num_channels > 6) { |
||

729 | av_log_ask_for_sample(s->avctx, |
||

730 | e0b1d660 | Diego Biurrun | ```
"coupled channels > 6\n");
``` |

731 | c1061cc7 | Sascha Sommer | ```
} else {
``` |

732 | memcpy(chgroup->decorrelation_matrix, |
||

733 | e0b1d660 | Diego Biurrun | default_decorrelation[chgroup->num_channels], |

734 | chgroup->num_channels * chgroup->num_channels * |
||

735 | ```
sizeof(*chgroup->decorrelation_matrix));
``` |
||

736 | c1061cc7 | Sascha Sommer | } |

737 | } |
||

738 | } |
||

739 | } |
||

740 | |||

741 | ```
/** decode transform on / off */
``` |
||

742 | ```
if (chgroup->transform) {
``` |
||

743 | ```
if (!get_bits1(&s->gb)) {
``` |
||

744 | ```
int i;
``` |
||

745 | ```
/** transform can be enabled for individual bands */
``` |
||

746 | for (i = 0; i < s->num_bands; i++) { |
||

747 | chgroup->transform_band[i] = get_bits1(&s->gb); |
||

748 | } |
||

749 | ```
} else {
``` |
||

750 | ```
memset(chgroup->transform_band, 1, s->num_bands);
``` |
||

751 | } |
||

752 | } |
||

753 | remaining_channels -= chgroup->num_channels; |
||

754 | } |
||

755 | } |
||

756 | return 0; |
||

757 | } |
||

758 | |||

759 | ```
/**
``` |
||

760 | 85fecafe | Sascha Sommer | ```
*@brief Extract the coefficients from the bitstream.
``` |

761 | ```
*@param s codec context
``` |
||

762 | ```
*@param c current channel number
``` |
||

763 | ```
*@return 0 on success, < 0 in case of bitstream errors
``` |
||

764 | ```
*/
``` |
||

765 | c1061cc7 | Sascha Sommer | static int decode_coeffs(WMAProDecodeCtx *s, int c) |

766 | 85fecafe | Sascha Sommer | { |

767 | 4df254f1 | Måns Rullgård | ```
/* Integers 0..15 as single-precision floats. The table saves a
``` |

768 | ```
costly int to float conversion, and storing the values as
``` |
||

769 | ```
integers allows fast sign-flipping. */
``` |
||

770 | static const int fval_tab[16] = { |
||

771 | 0x00000000, 0x3f800000, 0x40000000, 0x40400000, |
||

772 | 0x40800000, 0x40a00000, 0x40c00000, 0x40e00000, |
||

773 | 0x41000000, 0x41100000, 0x41200000, 0x41300000, |
||

774 | 0x41400000, 0x41500000, 0x41600000, 0x41700000, |
||

775 | }; |
||

776 | 85fecafe | Sascha Sommer | ```
int vlctable;
``` |

777 | VLC* vlc; |
||

778 | c1061cc7 | Sascha Sommer | WMAProChannelCtx* ci = &s->channel[c]; |

779 | 85fecafe | Sascha Sommer | int rl_mode = 0; |

780 | int cur_coeff = 0; |
||

781 | int num_zeros = 0; |
||

782 | ```
const uint16_t* run;
``` |
||

783 | 076a9dea | Måns Rullgård | const float* level; |

784 | 85fecafe | Sascha Sommer | |

785 | ```
dprintf(s->avctx, "decode coefficients for channel %i\n", c);
``` |
||

786 | |||

787 | vlctable = get_bits1(&s->gb); |
||

788 | vlc = &coef_vlc[vlctable]; |
||

789 | |||

790 | ```
if (vlctable) {
``` |
||

791 | run = coef1_run; |
||

792 | level = coef1_level; |
||

793 | ```
} else {
``` |
||

794 | run = coef0_run; |
||

795 | level = coef0_level; |
||

796 | } |
||

797 | |||

798 | ```
/** decode vector coefficients (consumes up to 167 bits per iteration for
``` |
||

799 | ```
4 vector coded large values) */
``` |
||

800 | while (!rl_mode && cur_coeff + 3 < s->subframe_len) { |
||

801 | int vals[4]; |
||

802 | ```
int i;
``` |
||

803 | unsigned int idx; |
||

804 | |||

805 | idx = get_vlc2(&s->gb, vec4_vlc.table, VLCBITS, VEC4MAXDEPTH); |
||

806 | |||

807 | ae925315 | Diego Biurrun | if (idx == HUFF_VEC4_SIZE - 1) { |

808 | 85fecafe | Sascha Sommer | for (i = 0; i < 4; i += 2) { |

809 | idx = get_vlc2(&s->gb, vec2_vlc.table, VLCBITS, VEC2MAXDEPTH); |
||

810 | ae925315 | Diego Biurrun | if (idx == HUFF_VEC2_SIZE - 1) { |

811 | 4df254f1 | Måns Rullgård | ```
int v0, v1;
``` |

812 | v0 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH); |
||

813 | if (v0 == HUFF_VEC1_SIZE - 1) |
||

814 | v0 += ff_wma_get_large_val(&s->gb); |
||

815 | v1 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH); |
||

816 | if (v1 == HUFF_VEC1_SIZE - 1) |
||

817 | v1 += ff_wma_get_large_val(&s->gb); |
||

818 | ```
((float*)vals)[i ] = v0;
``` |
||

819 | ((float*)vals)[i+1] = v1; |
||

820 | 85fecafe | Sascha Sommer | ```
} else {
``` |

821 | 4df254f1 | Måns Rullgård | ```
vals[i] = fval_tab[symbol_to_vec2[idx] >> 4 ];
``` |

822 | vals[i+1] = fval_tab[symbol_to_vec2[idx] & 0xF]; |
||

823 | 85fecafe | Sascha Sommer | } |

824 | } |
||

825 | ```
} else {
``` |
||

826 | 4df254f1 | Måns Rullgård | vals[0] = fval_tab[ symbol_to_vec4[idx] >> 12 ]; |

827 | vals[1] = fval_tab[(symbol_to_vec4[idx] >> 8) & 0xF]; |
||

828 | vals[2] = fval_tab[(symbol_to_vec4[idx] >> 4) & 0xF]; |
||

829 | vals[3] = fval_tab[ symbol_to_vec4[idx] & 0xF]; |
||

830 | 85fecafe | Sascha Sommer | } |

831 | |||

832 | ```
/** decode sign */
``` |
||

833 | for (i = 0; i < 4; i++) { |
||

834 | ```
if (vals[i]) {
``` |
||

835 | int sign = get_bits1(&s->gb) - 1; |
||

836 | 4df254f1 | Måns Rullgård | ```
*(uint32_t*)&ci->coeffs[cur_coeff] = vals[i] ^ sign<<31;
``` |

837 | 85fecafe | Sascha Sommer | ```
num_zeros = 0;
``` |

838 | ```
} else {
``` |
||

839 | c1061cc7 | Sascha Sommer | ```
ci->coeffs[cur_coeff] = 0;
``` |

840 | 85fecafe | Sascha Sommer | ```
/** switch to run level mode when subframe_len / 128 zeros
``` |

841 | e0b1d660 | Diego Biurrun | ```
were found in a row */
``` |

842 | ```
rl_mode |= (++num_zeros > s->subframe_len >> 8);
``` |
||

843 | 85fecafe | Sascha Sommer | } |

844 | ++cur_coeff; |
||

845 | } |
||

846 | } |
||

847 | |||

848 | ```
/** decode run level coded coefficients */
``` |
||

849 | ```
if (rl_mode) {
``` |
||

850 | c1061cc7 | Sascha Sommer | ```
memset(&ci->coeffs[cur_coeff], 0,
``` |

851 | ```
sizeof(*ci->coeffs) * (s->subframe_len - cur_coeff));
``` |
||

852 | ae925315 | Diego Biurrun | ```
if (ff_wma_run_level_decode(s->avctx, &s->gb, vlc,
``` |

853 | ```
level, run, 1, ci->coeffs,
``` |
||

854 | cur_coeff, s->subframe_len, |
||

855 | ```
s->subframe_len, s->esc_len, 0))
``` |
||

856 | 85fecafe | Sascha Sommer | ```
return AVERROR_INVALIDDATA;
``` |

857 | } |
||

858 | |||

859 | return 0; |
||

860 | } |
||

861 | |||

862 | ```
/**
``` |
||

863 | c1061cc7 | Sascha Sommer | ```
*@brief Extract scale factors from the bitstream.
``` |

864 | ```
*@param s codec context
``` |
||

865 | ```
*@return 0 on success, < 0 in case of bitstream errors
``` |
||

866 | ```
*/
``` |
||

867 | static int decode_scale_factors(WMAProDecodeCtx* s) |
||

868 | { |
||

869 | ```
int i;
``` |
||

870 | |||

871 | ```
/** should never consume more than 5344 bits
``` |
||

872 | ```
* MAX_CHANNELS * (1 + MAX_BANDS * 23)
``` |
||

873 | ```
*/
``` |
||

874 | |||

875 | for (i = 0; i < s->channels_for_cur_subframe; i++) { |
||

876 | ```
int c = s->channel_indexes_for_cur_subframe[i];
``` |
||

877 | ```
int* sf;
``` |
||

878 | 7dca334d | Sascha Sommer | ```
int* sf_end;
``` |

879 | s->channel[c].scale_factors = s->channel[c].saved_scale_factors[!s->channel[c].scale_factor_idx]; |
||

880 | sf_end = s->channel[c].scale_factors + s->num_bands; |
||

881 | c1061cc7 | Sascha Sommer | |

882 | ```
/** resample scale factors for the new block size
``` |
||

883 | ```
* as the scale factors might need to be resampled several times
``` |
||

884 | ```
* before some new values are transmitted, a backup of the last
``` |
||

885 | ```
* transmitted scale factors is kept in saved_scale_factors
``` |
||

886 | ```
*/
``` |
||

887 | ```
if (s->channel[c].reuse_sf) {
``` |
||

888 | ```
const int8_t* sf_offsets = s->sf_offsets[s->table_idx][s->channel[c].table_idx];
``` |
||

889 | ```
int b;
``` |
||

890 | for (b = 0; b < s->num_bands; b++) |
||

891 | s->channel[c].scale_factors[b] = |
||

892 | 7dca334d | Sascha Sommer | s->channel[c].saved_scale_factors[s->channel[c].scale_factor_idx][*sf_offsets++]; |

893 | c1061cc7 | Sascha Sommer | } |

894 | |||

895 | ```
if (!s->channel[c].cur_subframe || get_bits1(&s->gb)) {
``` |
||

896 | |||

897 | ```
if (!s->channel[c].reuse_sf) {
``` |
||

898 | ```
int val;
``` |
||

899 | ```
/** decode DPCM coded scale factors */
``` |
||

900 | s->channel[c].scale_factor_step = get_bits(&s->gb, 2) + 1; |
||

901 | ```
val = 45 / s->channel[c].scale_factor_step;
``` |
||

902 | ```
for (sf = s->channel[c].scale_factors; sf < sf_end; sf++) {
``` |
||

903 | ```
val += get_vlc2(&s->gb, sf_vlc.table, SCALEVLCBITS, SCALEMAXDEPTH) - 60;
``` |
||

904 | *sf = val; |
||

905 | } |
||

906 | ```
} else {
``` |
||

907 | ```
int i;
``` |
||

908 | ```
/** run level decode differences to the resampled factors */
``` |
||

909 | for (i = 0; i < s->num_bands; i++) { |
||

910 | ```
int idx;
``` |
||

911 | ```
int skip;
``` |
||

912 | ```
int val;
``` |
||

913 | ```
int sign;
``` |
||

914 | |||

915 | idx = get_vlc2(&s->gb, sf_rl_vlc.table, VLCBITS, SCALERLMAXDEPTH); |
||

916 | |||

917 | e0b1d660 | Diego Biurrun | ```
if (!idx) {
``` |

918 | c1061cc7 | Sascha Sommer | ```
uint32_t code = get_bits(&s->gb, 14);
``` |

919 | ```
val = code >> 6;
``` |
||

920 | sign = (code & 1) - 1; |
||

921 | skip = (code & 0x3f) >> 1; |
||

922 | } else if (idx == 1) { |
||

923 | ```
break;
``` |
||

924 | ```
} else {
``` |
||

925 | skip = scale_rl_run[idx]; |
||

926 | val = scale_rl_level[idx]; |
||

927 | ```
sign = get_bits1(&s->gb)-1;
``` |
||

928 | } |
||

929 | |||

930 | i += skip; |
||

931 | ```
if (i >= s->num_bands) {
``` |
||

932 | e0b1d660 | Diego Biurrun | av_log(s->avctx, AV_LOG_ERROR, |

933 | c1061cc7 | Sascha Sommer | ```
"invalid scale factor coding\n");
``` |

934 | ```
return AVERROR_INVALIDDATA;
``` |
||

935 | } |
||

936 | s->channel[c].scale_factors[i] += (val ^ sign) - sign; |
||

937 | } |
||

938 | } |
||

939 | 7dca334d | Sascha Sommer | ```
/** swap buffers */
``` |

940 | s->channel[c].scale_factor_idx = !s->channel[c].scale_factor_idx; |
||

941 | c1061cc7 | Sascha Sommer | s->channel[c].table_idx = s->table_idx; |

942 | ```
s->channel[c].reuse_sf = 1;
``` |
||

943 | } |
||

944 | |||

945 | ```
/** calculate new scale factor maximum */
``` |
||

946 | ```
s->channel[c].max_scale_factor = s->channel[c].scale_factors[0];
``` |
||

947 | for (sf = s->channel[c].scale_factors + 1; sf < sf_end; sf++) { |
||

948 | s->channel[c].max_scale_factor = |
||

949 | FFMAX(s->channel[c].max_scale_factor, *sf); |
||

950 | } |
||

951 | |||

952 | } |
||

953 | return 0; |
||

954 | } |
||

955 | |||

956 | ```
/**
``` |
||

957 | da136c7e | Sascha Sommer | ```
*@brief Reconstruct the individual channel data.
``` |

958 | ```
*@param s codec context
``` |
||

959 | ```
*/
``` |
||

960 | c1061cc7 | Sascha Sommer | static void inverse_channel_transform(WMAProDecodeCtx *s) |

961 | da136c7e | Sascha Sommer | { |

962 | ```
int i;
``` |
||

963 | |||

964 | b25a8818 | Diego Biurrun | for (i = 0; i < s->num_chgroups; i++) { |

965 | f53e96ed | Sascha Sommer | ```
if (s->chgroup[i].transform) {
``` |

966 | da136c7e | Sascha Sommer | ```
float data[WMAPRO_MAX_CHANNELS];
``` |

967 | const int num_channels = s->chgroup[i].num_channels; |
||

968 | ```
float** ch_data = s->chgroup[i].channel_data;
``` |
||

969 | ```
float** ch_end = ch_data + num_channels;
``` |
||

970 | ```
const int8_t* tb = s->chgroup[i].transform_band;
``` |
||

971 | int16_t* sfb; |
||

972 | |||

973 | ```
/** multichannel decorrelation */
``` |
||

974 | b979e4a2 | Diego Biurrun | ```
for (sfb = s->cur_sfb_offsets;
``` |

975 | e0b1d660 | Diego Biurrun | sfb < s->cur_sfb_offsets + s->num_bands; sfb++) { |

976 | f53e96ed | Sascha Sommer | ```
int y;
``` |

977 | da136c7e | Sascha Sommer | if (*tb++ == 1) { |

978 | ```
/** multiply values with the decorrelation_matrix */
``` |
||

979 | b25a8818 | Diego Biurrun | for (y = sfb[0]; y < FFMIN(sfb[1], s->subframe_len); y++) { |

980 | da136c7e | Sascha Sommer | const float* mat = s->chgroup[i].decorrelation_matrix; |

981 | b25a8818 | Diego Biurrun | const float* data_end = data + num_channels; |

982 | ```
float* data_ptr = data;
``` |
||

983 | da136c7e | Sascha Sommer | ```
float** ch;
``` |

984 | |||

985 | b979e4a2 | Diego Biurrun | ```
for (ch = ch_data; ch < ch_end; ch++)
``` |

986 | e0b1d660 | Diego Biurrun | *data_ptr++ = (*ch)[y]; |

987 | da136c7e | Sascha Sommer | |

988 | ```
for (ch = ch_data; ch < ch_end; ch++) {
``` |
||

989 | float sum = 0; |
||

990 | data_ptr = data; |
||

991 | ```
while (data_ptr < data_end)
``` |
||

992 | sum += *data_ptr++ * *mat++; |
||

993 | |||

994 | (*ch)[y] = sum; |
||

995 | } |
||

996 | } |
||

997 | f53e96ed | Sascha Sommer | } else if (s->num_channels == 2) { |

998 | d975e5e9 | Måns Rullgård | int len = FFMIN(sfb[1], s->subframe_len) - sfb[0]; |

999 | s->dsp.vector_fmul_scalar(ch_data[0] + sfb[0], |
||

1000 | ch_data[0] + sfb[0], |
||

1001 | 181.0 / 128, len); |
||

1002 | s->dsp.vector_fmul_scalar(ch_data[1] + sfb[0], |
||

1003 | ch_data[1] + sfb[0], |
||

1004 | 181.0 / 128, len); |
||

1005 | da136c7e | Sascha Sommer | } |

1006 | } |
||

1007 | } |
||

1008 | } |
||

1009 | } |
||

1010 | |||

1011 | c1061cc7 | Sascha Sommer | ```
/**
``` |

1012 | ```
*@brief Apply sine window and reconstruct the output buffer.
``` |
||

1013 | ```
*@param s codec context
``` |
||

1014 | ```
*/
``` |
||

1015 | static void wmapro_window(WMAProDecodeCtx *s) |
||

1016 | { |
||

1017 | ```
int i;
``` |
||

1018 | e0b1d660 | Diego Biurrun | for (i = 0; i < s->channels_for_cur_subframe; i++) { |

1019 | c1061cc7 | Sascha Sommer | ```
int c = s->channel_indexes_for_cur_subframe[i];
``` |

1020 | ```
float* window;
``` |
||

1021 | ```
int winlen = s->channel[c].prev_block_len;
``` |
||

1022 | float* start = s->channel[c].coeffs - (winlen >> 1); |
||

1023 | |||

1024 | ```
if (s->subframe_len < winlen) {
``` |
||

1025 | e0b1d660 | Diego Biurrun | ```
start += (winlen - s->subframe_len) >> 1;
``` |

1026 | c1061cc7 | Sascha Sommer | winlen = s->subframe_len; |

1027 | } |
||

1028 | |||

1029 | e0b1d660 | Diego Biurrun | window = s->windows[av_log2(winlen) - BLOCK_MIN_BITS]; |

1030 | c1061cc7 | Sascha Sommer | |

1031 | ```
winlen >>= 1;
``` |
||

1032 | |||

1033 | s->dsp.vector_fmul_window(start, start, start + winlen, |
||

1034 | ```
window, 0, winlen);
``` |
||

1035 | |||

1036 | s->channel[c].prev_block_len = s->subframe_len; |
||

1037 | } |
||

1038 | } |
||

1039 | |||

1040 | ```
/**
``` |
||

1041 | ```
*@brief Decode a single subframe (block).
``` |
||

1042 | ```
*@param s codec context
``` |
||

1043 | ```
*@return 0 on success, < 0 when decoding failed
``` |
||

1044 | ```
*/
``` |
||

1045 | static int decode_subframe(WMAProDecodeCtx *s) |
||

1046 | { |
||

1047 | ```
int offset = s->samples_per_frame;
``` |
||

1048 | ```
int subframe_len = s->samples_per_frame;
``` |
||

1049 | ```
int i;
``` |
||

1050 | ```
int total_samples = s->samples_per_frame * s->num_channels;
``` |
||

1051 | int transmit_coeffs = 0; |
||

1052 | ```
int cur_subwoofer_cutoff;
``` |
||

1053 | |||

1054 | s->subframe_offset = get_bits_count(&s->gb); |
||

1055 | |||

1056 | ```
/** reset channel context and find the next block offset and size
``` |
||

1057 | ```
== the next block of the channel with the smallest number of
``` |
||

1058 | ```
decoded samples
``` |
||

1059 | ```
*/
``` |
||

1060 | for (i = 0; i < s->num_channels; i++) { |
||

1061 | ```
s->channel[i].grouped = 0;
``` |
||

1062 | ```
if (offset > s->channel[i].decoded_samples) {
``` |
||

1063 | offset = s->channel[i].decoded_samples; |
||

1064 | subframe_len = |
||

1065 | s->channel[i].subframe_len[s->channel[i].cur_subframe]; |
||

1066 | } |
||

1067 | } |
||

1068 | |||

1069 | dprintf(s->avctx, |
||

1070 | e0b1d660 | Diego Biurrun | ```
"processing subframe with offset %i len %i\n", offset, subframe_len);
``` |

1071 | c1061cc7 | Sascha Sommer | |

1072 | ```
/** get a list of all channels that contain the estimated block */
``` |
||

1073 | ```
s->channels_for_cur_subframe = 0;
``` |
||

1074 | for (i = 0; i < s->num_channels; i++) { |
||

1075 | const int cur_subframe = s->channel[i].cur_subframe; |
||

1076 | ```
/** substract already processed samples */
``` |
||

1077 | total_samples -= s->channel[i].decoded_samples; |
||

1078 | |||

1079 | ```
/** and count if there are multiple subframes that match our profile */
``` |
||

1080 | ```
if (offset == s->channel[i].decoded_samples &&
``` |
||

1081 | e0b1d660 | Diego Biurrun | subframe_len == s->channel[i].subframe_len[cur_subframe]) { |

1082 | c1061cc7 | Sascha Sommer | total_samples -= s->channel[i].subframe_len[cur_subframe]; |

1083 | s->channel[i].decoded_samples += |
||

1084 | s->channel[i].subframe_len[cur_subframe]; |
||

1085 | s->channel_indexes_for_cur_subframe[s->channels_for_cur_subframe] = i; |
||

1086 | ++s->channels_for_cur_subframe; |
||

1087 | } |
||

1088 | } |
||

1089 | |||

1090 | ```
/** check if the frame will be complete after processing the
``` |
||

1091 | ```
estimated block */
``` |
||

1092 | ```
if (!total_samples)
``` |
||

1093 | ```
s->parsed_all_subframes = 1;
``` |
||

1094 | |||

1095 | |||

1096 | ```
dprintf(s->avctx, "subframe is part of %i channels\n",
``` |
||

1097 | e0b1d660 | Diego Biurrun | s->channels_for_cur_subframe); |

1098 | c1061cc7 | Sascha Sommer | |

1099 | ```
/** calculate number of scale factor bands and their offsets */
``` |
||

1100 | s->table_idx = av_log2(s->samples_per_frame/subframe_len); |
||

1101 | s->num_bands = s->num_sfb[s->table_idx]; |
||

1102 | s->cur_sfb_offsets = s->sfb_offsets[s->table_idx]; |
||

1103 | cur_subwoofer_cutoff = s->subwoofer_cutoffs[s->table_idx]; |
||

1104 | |||

1105 | ```
/** configure the decoder for the current subframe */
``` |
||

1106 | for (i = 0; i < s->channels_for_cur_subframe; i++) { |
||

1107 | ```
int c = s->channel_indexes_for_cur_subframe[i];
``` |
||

1108 | |||

1109 | e0b1d660 | Diego Biurrun | ```
s->channel[c].coeffs = &s->channel[c].out[(s->samples_per_frame >> 1)
``` |

1110 | c1061cc7 | Sascha Sommer | + offset]; |

1111 | } |
||

1112 | |||

1113 | s->subframe_len = subframe_len; |
||

1114 | s->esc_len = av_log2(s->subframe_len - 1) + 1; |
||

1115 | |||

1116 | ```
/** skip extended header if any */
``` |
||

1117 | ```
if (get_bits1(&s->gb)) {
``` |
||

1118 | ```
int num_fill_bits;
``` |
||

1119 | if (!(num_fill_bits = get_bits(&s->gb, 2))) { |
||

1120 | int len = get_bits(&s->gb, 4); |
||

1121 | ```
num_fill_bits = get_bits(&s->gb, len) + 1;
``` |
||

1122 | } |
||

1123 | |||

1124 | if (num_fill_bits >= 0) { |
||

1125 | ```
if (get_bits_count(&s->gb) + num_fill_bits > s->num_saved_bits) {
``` |
||

1126 | e0b1d660 | Diego Biurrun | ```
av_log(s->avctx, AV_LOG_ERROR, "invalid number of fill bits\n");
``` |

1127 | c1061cc7 | Sascha Sommer | ```
return AVERROR_INVALIDDATA;
``` |

1128 | } |
||

1129 | |||

1130 | skip_bits_long(&s->gb, num_fill_bits); |
||

1131 | } |
||

1132 | } |
||

1133 | |||

1134 | ```
/** no idea for what the following bit is used */
``` |
||

1135 | ```
if (get_bits1(&s->gb)) {
``` |
||

1136 | ```
av_log_ask_for_sample(s->avctx, "reserved bit set\n");
``` |
||

1137 | ```
return AVERROR_INVALIDDATA;
``` |
||

1138 | } |
||

1139 | |||

1140 | |||

1141 | if (decode_channel_transform(s) < 0) |
||

1142 | ```
return AVERROR_INVALIDDATA;
``` |
||

1143 | |||

1144 | |||

1145 | for (i = 0; i < s->channels_for_cur_subframe; i++) { |
||

1146 | ```
int c = s->channel_indexes_for_cur_subframe[i];
``` |
||

1147 | ```
if ((s->channel[c].transmit_coefs = get_bits1(&s->gb)))
``` |
||

1148 | ```
transmit_coeffs = 1;
``` |
||

1149 | } |
||

1150 | |||

1151 | ```
if (transmit_coeffs) {
``` |
||

1152 | ```
int step;
``` |
||

1153 | int quant_step = 90 * s->bits_per_sample >> 4; |
||

1154 | ```
if ((get_bits1(&s->gb))) {
``` |
||

1155 | ```
/** FIXME: might change run level mode decision */
``` |
||

1156 | ```
av_log_ask_for_sample(s->avctx, "unsupported quant step coding\n");
``` |
||

1157 | ```
return AVERROR_INVALIDDATA;
``` |
||

1158 | } |
||

1159 | ```
/** decode quantization step */
``` |
||

1160 | ```
step = get_sbits(&s->gb, 6);
``` |
||

1161 | quant_step += step; |
||

1162 | if (step == -32 || step == 31) { |
||

1163 | const int sign = (step == 31) - 1; |
||

1164 | int quant = 0; |
||

1165 | while (get_bits_count(&s->gb) + 5 < s->num_saved_bits && |
||

1166 | e0b1d660 | Diego Biurrun | (step = get_bits(&s->gb, 5)) == 31) { |

1167 | ```
quant += 31;
``` |
||

1168 | c1061cc7 | Sascha Sommer | } |

1169 | quant_step += ((quant + step) ^ sign) - sign; |
||

1170 | } |
||

1171 | if (quant_step < 0) { |
||

1172 | e0b1d660 | Diego Biurrun | ```
av_log(s->avctx, AV_LOG_DEBUG, "negative quant step\n");
``` |

1173 | c1061cc7 | Sascha Sommer | } |

1174 | |||

1175 | ```
/** decode quantization step modifiers for every channel */
``` |
||

1176 | |||

1177 | if (s->channels_for_cur_subframe == 1) { |
||

1178 | ```
s->channel[s->channel_indexes_for_cur_subframe[0]].quant_step = quant_step;
``` |
||

1179 | ```
} else {
``` |
||

1180 | int modifier_len = get_bits(&s->gb, 3); |
||

1181 | for (i = 0; i < s->channels_for_cur_subframe; i++) { |
||

1182 | ```
int c = s->channel_indexes_for_cur_subframe[i];
``` |
||

1183 | s->channel[c].quant_step = quant_step; |
||

1184 | ```
if (get_bits1(&s->gb)) {
``` |
||

1185 | ```
if (modifier_len) {
``` |
||

1186 | e0b1d660 | Diego Biurrun | ```
s->channel[c].quant_step += get_bits(&s->gb, modifier_len) + 1;
``` |

1187 | c1061cc7 | Sascha Sommer | ```
} else
``` |

1188 | ++s->channel[c].quant_step; |
||

1189 | } |
||

1190 | } |
||

1191 | } |
||

1192 | |||

1193 | ```
/** decode scale factors */
``` |
||

1194 | if (decode_scale_factors(s) < 0) |
||

1195 | ```
return AVERROR_INVALIDDATA;
``` |
||

1196 | } |
||

1197 | |||

1198 | ```
dprintf(s->avctx, "BITSTREAM: subframe header length was %i\n",
``` |
||

1199 | e0b1d660 | Diego Biurrun | get_bits_count(&s->gb) - s->subframe_offset); |

1200 | c1061cc7 | Sascha Sommer | |

1201 | ```
/** parse coefficients */
``` |
||

1202 | for (i = 0; i < s->channels_for_cur_subframe; i++) { |
||

1203 | ```
int c = s->channel_indexes_for_cur_subframe[i];
``` |
||

1204 | ```
if (s->channel[c].transmit_coefs &&
``` |
||

1205 | e0b1d660 | Diego Biurrun | get_bits_count(&s->gb) < s->num_saved_bits) { |

1206 | decode_coeffs(s, c); |
||

1207 | c1061cc7 | Sascha Sommer | ```
} else
``` |

1208 | ```
memset(s->channel[c].coeffs, 0,
``` |
||

1209 | ```
sizeof(*s->channel[c].coeffs) * subframe_len);
``` |
||

1210 | } |
||

1211 | |||

1212 | ```
dprintf(s->avctx, "BITSTREAM: subframe length was %i\n",
``` |
||

1213 | e0b1d660 | Diego Biurrun | get_bits_count(&s->gb) - s->subframe_offset); |

1214 | c1061cc7 | Sascha Sommer | |

1215 | ```
if (transmit_coeffs) {
``` |
||

1216 | ```
/** reconstruct the per channel data */
``` |
||

1217 | inverse_channel_transform(s); |
||

1218 | for (i = 0; i < s->channels_for_cur_subframe; i++) { |
||

1219 | ```
int c = s->channel_indexes_for_cur_subframe[i];
``` |
||

1220 | const int* sf = s->channel[c].scale_factors; |
||

1221 | ```
int b;
``` |
||

1222 | |||

1223 | ```
if (c == s->lfe_channel)
``` |
||

1224 | memset(&s->tmp[cur_subwoofer_cutoff], 0, sizeof(*s->tmp) * |
||

1225 | (subframe_len - cur_subwoofer_cutoff)); |
||

1226 | |||

1227 | ```
/** inverse quantization and rescaling */
``` |
||

1228 | for (b = 0; b < s->num_bands; b++) { |
||

1229 | const int end = FFMIN(s->cur_sfb_offsets[b+1], s->subframe_len); |
||

1230 | const int exp = s->channel[c].quant_step - |
||

1231 | (s->channel[c].max_scale_factor - *sf++) * |
||

1232 | s->channel[c].scale_factor_step; |
||

1233 | const float quant = pow(10.0, exp / 20.0); |
||

1234 | d975e5e9 | Måns Rullgård | ```
int start = s->cur_sfb_offsets[b];
``` |

1235 | s->dsp.vector_fmul_scalar(s->tmp + start, |
||

1236 | s->channel[c].coeffs + start, |
||

1237 | quant, end - start); |
||

1238 | c1061cc7 | Sascha Sommer | } |

1239 | |||

1240 | ```
/** apply imdct (ff_imdct_half == DCTIV with reverse) */
``` |
||

1241 | e0b1d660 | Diego Biurrun | ff_imdct_half(&s->mdct_ctx[av_log2(subframe_len) - BLOCK_MIN_BITS], |

1242 | c1061cc7 | Sascha Sommer | s->channel[c].coeffs, s->tmp); |

1243 | } |
||

1244 | } |
||

1245 | |||

1246 | ```
/** window and overlapp-add */
``` |
||

1247 | wmapro_window(s); |
||

1248 | |||

1249 | ```
/** handled one subframe */
``` |
||

1250 | for (i = 0; i < s->channels_for_cur_subframe; i++) { |
||

1251 | ```
int c = s->channel_indexes_for_cur_subframe[i];
``` |
||

1252 | ```
if (s->channel[c].cur_subframe >= s->channel[c].num_subframes) {
``` |
||

1253 | e0b1d660 | Diego Biurrun | ```
av_log(s->avctx, AV_LOG_ERROR, "broken subframe\n");
``` |

1254 | c1061cc7 | Sascha Sommer | ```
return AVERROR_INVALIDDATA;
``` |

1255 | } |
||

1256 | ++s->channel[c].cur_subframe; |
||

1257 | } |
||

1258 | |||

1259 | return 0; |
||

1260 | } |
||

1261 | |||

1262 | ```
/**
``` |
||

1263 | ```
*@brief Decode one WMA frame.
``` |
||

1264 | ```
*@param s codec context
``` |
||

1265 | ```
*@return 0 if the trailer bit indicates that this is the last frame,
``` |
||

1266 | ```
* 1 if there are additional frames
``` |
||

1267 | ```
*/
``` |
||

1268 | static int decode_frame(WMAProDecodeCtx *s) |
||

1269 | { |
||

1270 | GetBitContext* gb = &s->gb; |
||

1271 | int more_frames = 0; |
||

1272 | int len = 0; |
||

1273 | ```
int i;
``` |
||

1274 | |||

1275 | ```
/** check for potential output buffer overflow */
``` |
||

1276 | ```
if (s->num_channels * s->samples_per_frame > s->samples_end - s->samples) {
``` |
||

1277 | 7551a559 | Sascha Sommer | ```
/** return an error if no frame could be decoded at all */
``` |

1278 | 5f28b5e7 | Sascha Sommer | av_log(s->avctx, AV_LOG_ERROR, |

1279 | ```
"not enough space for the output samples\n");
``` |
||

1280 | ```
s->packet_loss = 1;
``` |
||

1281 | c1061cc7 | Sascha Sommer | return 0; |

1282 | } |
||

1283 | |||

1284 | ```
/** get frame length */
``` |
||

1285 | ```
if (s->len_prefix)
``` |
||

1286 | len = get_bits(gb, s->log2_frame_size); |
||

1287 | |||

1288 | ```
dprintf(s->avctx, "decoding frame with length %x\n", len);
``` |
||

1289 | |||

1290 | ```
/** decode tile information */
``` |
||

1291 | ```
if (decode_tilehdr(s)) {
``` |
||

1292 | ```
s->packet_loss = 1;
``` |
||

1293 | return 0; |
||

1294 | } |
||

1295 | |||

1296 | ```
/** read postproc transform */
``` |
||

1297 | if (s->num_channels > 1 && get_bits1(gb)) { |
||

1298 | ```
av_log_ask_for_sample(s->avctx, "Unsupported postproc transform found\n");
``` |
||

1299 | ```
s->packet_loss = 1;
``` |
||

1300 | return 0; |
||

1301 | } |
||

1302 | |||

1303 | ```
/** read drc info */
``` |
||

1304 | ```
if (s->dynamic_range_compression) {
``` |
||

1305 | ```
s->drc_gain = get_bits(gb, 8);
``` |
||

1306 | ```
dprintf(s->avctx, "drc_gain %i\n", s->drc_gain);
``` |
||

1307 | } |
||

1308 | |||

1309 | ```
/** no idea what these are for, might be the number of samples
``` |
||

1310 | ```
that need to be skipped at the beginning or end of a stream */
``` |
||

1311 | ```
if (get_bits1(gb)) {
``` |
||

1312 | ```
int skip;
``` |
||

1313 | |||

1314 | ```
/** usually true for the first frame */
``` |
||

1315 | ```
if (get_bits1(gb)) {
``` |
||

1316 | ```
skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
``` |
||

1317 | ```
dprintf(s->avctx, "start skip: %i\n", skip);
``` |
||

1318 | } |
||

1319 | |||

1320 | ```
/** sometimes true for the last frame */
``` |
||

1321 | ```
if (get_bits1(gb)) {
``` |
||

1322 | ```
skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
``` |
||

1323 | ```
dprintf(s->avctx, "end skip: %i\n", skip);
``` |
||

1324 | } |
||

1325 | |||

1326 | } |
||

1327 | |||

1328 | ```
dprintf(s->avctx, "BITSTREAM: frame header length was %i\n",
``` |
||

1329 | e0b1d660 | Diego Biurrun | get_bits_count(gb) - s->frame_offset); |

1330 | c1061cc7 | Sascha Sommer | |

1331 | ```
/** reset subframe states */
``` |
||

1332 | ```
s->parsed_all_subframes = 0;
``` |
||

1333 | for (i = 0; i < s->num_channels; i++) { |
||

1334 | ```
s->channel[i].decoded_samples = 0;
``` |
||

1335 | ```
s->channel[i].cur_subframe = 0;
``` |
||

1336 | ```
s->channel[i].reuse_sf = 0;
``` |
||

1337 | } |
||

1338 | |||

1339 | ```
/** decode all subframes */
``` |
||

1340 | ```
while (!s->parsed_all_subframes) {
``` |
||

1341 | if (decode_subframe(s) < 0) { |
||

1342 | ```
s->packet_loss = 1;
``` |
||

1343 | return 0; |
||

1344 | } |
||

1345 | } |
||

1346 | |||

1347 | ```
/** interleave samples and write them to the output buffer */
``` |
||

1348 | for (i = 0; i < s->num_channels; i++) { |
||

1349 | ```
float* ptr;
``` |
||

1350 | ```
int incr = s->num_channels;
``` |
||

1351 | ```
float* iptr = s->channel[i].out;
``` |
||

1352 | ```
int x;
``` |
||

1353 | |||

1354 | ptr = s->samples + i; |
||

1355 | |||

1356 | for (x = 0; x < s->samples_per_frame; x++) { |
||

1357 | *ptr = av_clipf(*iptr++, -1.0, 32767.0 / 32768.0); |
||

1358 | ptr += incr; |
||

1359 | } |
||

1360 | |||

1361 | ```
/** reuse second half of the IMDCT output for the next frame */
``` |
||

1362 | ```
memcpy(&s->channel[i].out[0],
``` |
||

1363 | &s->channel[i].out[s->samples_per_frame], |
||

1364 | s->samples_per_frame * sizeof(*s->channel[i].out) >> 1); |
||

1365 | } |
||

1366 | |||

1367 | ```
if (s->skip_frame) {
``` |
||

1368 | ```
s->skip_frame = 0;
``` |
||

1369 | ```
} else
``` |
||

1370 | s->samples += s->num_channels * s->samples_per_frame; |
||

1371 | |||

1372 | if (len != (get_bits_count(gb) - s->frame_offset) + 2) { |
||

1373 | ```
/** FIXME: not sure if this is always an error */
``` |
||

1374 | e0b1d660 | Diego Biurrun | ```
av_log(s->avctx, AV_LOG_ERROR, "frame[%i] would have to skip %i bits\n",
``` |

1375 | c1061cc7 | Sascha Sommer | ```
s->frame_num, len - (get_bits_count(gb) - s->frame_offset) - 1);
``` |

1376 | ```
s->packet_loss = 1;
``` |
||

1377 | return 0; |
||

1378 | } |
||

1379 | |||

1380 | ```
/** skip the rest of the frame data */
``` |
||

1381 | ```
skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
``` |
||

1382 | |||

1383 | ```
/** decode trailer bit */
``` |
||

1384 | more_frames = get_bits1(gb); |
||

1385 | |||

1386 | ++s->frame_num; |
||

1387 | ```
return more_frames;
``` |
||

1388 | } |
||

1389 | |||

1390 | ```
/**
``` |
||

1391 | ```
*@brief Calculate remaining input buffer length.
``` |
||

1392 | ```
*@param s codec context
``` |
||

1393 | ```
*@param gb bitstream reader context
``` |
||

1394 | ```
*@return remaining size in bits
``` |
||

1395 | ```
*/
``` |
||

1396 | e0b1d660 | Diego Biurrun | static int remaining_bits(WMAProDecodeCtx *s, GetBitContext *gb) |

1397 | c1061cc7 | Sascha Sommer | { |

1398 | ```
return s->buf_bit_size - get_bits_count(gb);
``` |
||

1399 | } |
||

1400 | |||

1401 | ```
/**
``` |
||

1402 | ```
*@brief Fill the bit reservoir with a (partial) frame.
``` |
||

1403 | ```
*@param s codec context
``` |
||

1404 | ```
*@param gb bitstream reader context
``` |
||

1405 | ```
*@param len length of the partial frame
``` |
||

1406 | ```
*@param append decides wether to reset the buffer or not
``` |
||

1407 | ```
*/
``` |
||

1408 | static void save_bits(WMAProDecodeCtx *s, GetBitContext* gb, int len, |
||

1409 | e0b1d660 | Diego Biurrun | ```
int append)
``` |

1410 | c1061cc7 | Sascha Sommer | { |

1411 | ```
int buflen;
``` |
||

1412 | |||

1413 | ```
/** when the frame data does not need to be concatenated, the input buffer
``` |
||

1414 | ```
is resetted and additional bits from the previous frame are copyed
``` |
||

1415 | ```
and skipped later so that a fast byte copy is possible */
``` |
||

1416 | |||

1417 | ```
if (!append) {
``` |
||

1418 | ```
s->frame_offset = get_bits_count(gb) & 7;
``` |
||

1419 | s->num_saved_bits = s->frame_offset; |
||

1420 | init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE); |
||

1421 | } |
||

1422 | |||

1423 | buflen = (s->num_saved_bits + len + 8) >> 3; |
||

1424 | |||

1425 | if (len <= 0 || buflen > MAX_FRAMESIZE) { |
||

1426 | e0b1d660 | Diego Biurrun | ```
av_log_ask_for_sample(s->avctx, "input buffer too small\n");
``` |

1427 | ```
s->packet_loss = 1;
``` |
||

1428 | ```
return;
``` |
||

1429 | c1061cc7 | Sascha Sommer | } |

1430 | |||

1431 | s->num_saved_bits += len; |
||

1432 | ```
if (!append) {
``` |
||

1433 | e0b1d660 | Diego Biurrun | ```
ff_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
``` |

1434 | s->num_saved_bits); |
||

1435 | c1061cc7 | Sascha Sommer | ```
} else {
``` |

1436 | int align = 8 - (get_bits_count(gb) & 7); |
||

1437 | align = FFMIN(align, len); |
||

1438 | put_bits(&s->pb, align, get_bits(gb, align)); |
||

1439 | len -= align; |
||

1440 | ```
ff_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
``` |
||

1441 | } |
||

1442 | skip_bits_long(gb, len); |
||

1443 | |||

1444 | { |
||

1445 | e0b1d660 | Diego Biurrun | PutBitContext tmp = s->pb; |

1446 | flush_put_bits(&tmp); |
||

1447 | c1061cc7 | Sascha Sommer | } |

1448 | |||

1449 | init_get_bits(&s->gb, s->frame_data, s->num_saved_bits); |
||

1450 | skip_bits(&s->gb, s->frame_offset); |
||

1451 | } |
||

1452 | |||

1453 | ```
/**
``` |
||

1454 | ```
*@brief Decode a single WMA packet.
``` |
||

1455 | ```
*@param avctx codec context
``` |
||

1456 | ```
*@param data the output buffer
``` |
||

1457 | ```
*@param data_size number of bytes that were written to the output buffer
``` |
||

1458 | ```
*@param avpkt input packet
``` |
||

1459 | ```
*@return number of bytes that were read from the input buffer
``` |
||

1460 | ```
*/
``` |
||

1461 | static int decode_packet(AVCodecContext *avctx, |
||

1462 | e0b1d660 | Diego Biurrun | void *data, int *data_size, AVPacket* avpkt) |

1463 | c1061cc7 | Sascha Sommer | { |

1464 | WMAProDecodeCtx *s = avctx->priv_data; |
||

1465 | 9244370a | Sascha Sommer | GetBitContext* gb = &s->pgb; |

1466 | ```
const uint8_t* buf = avpkt->data;
``` |
||

1467 | ```
int buf_size = avpkt->size;
``` |
||

1468 | c1061cc7 | Sascha Sommer | ```
int num_bits_prev_frame;
``` |

1469 | ```
int packet_sequence_number;
``` |
||

1470 | |||

1471 | 9244370a | Sascha Sommer | s->samples = data; |

1472 | ```
s->samples_end = (float*)((int8_t*)data + *data_size);
``` |
||

1473 | c1061cc7 | Sascha Sommer | ```
*data_size = 0;
``` |

1474 | |||

1475 | 5f28b5e7 | Sascha Sommer | ```
if (s->packet_done || s->packet_loss) {
``` |

1476 | ```
s->packet_done = 0;
``` |
||

1477 | 9244370a | Sascha Sommer | ```
s->buf_bit_size = buf_size << 3;
``` |

1478 | 7551a559 | Sascha Sommer | |

1479 | 9244370a | Sascha Sommer | ```
/** sanity check for the buffer length */
``` |

1480 | ```
if (buf_size < avctx->block_align)
``` |
||

1481 | return 0; |
||

1482 | c1061cc7 | Sascha Sommer | |

1483 | 9244370a | Sascha Sommer | buf_size = avctx->block_align; |

1484 | c1061cc7 | Sascha Sommer | |

1485 | 9244370a | Sascha Sommer | ```
/** parse packet header */
``` |

1486 | init_get_bits(gb, buf, s->buf_bit_size); |
||

1487 | ```
packet_sequence_number = get_bits(gb, 4);
``` |
||

1488 | ```
skip_bits(gb, 2);
``` |
||

1489 | c1061cc7 | Sascha Sommer | |

1490 | 9244370a | Sascha Sommer | ```
/** get number of bits that need to be added to the previous frame */
``` |

1491 | num_bits_prev_frame = get_bits(gb, s->log2_frame_size); |
||

1492 | ```
dprintf(avctx, "packet[%d]: nbpf %x\n", avctx->frame_number,
``` |
||

1493 | num_bits_prev_frame); |
||

1494 | c1061cc7 | Sascha Sommer | |

1495 | 9244370a | Sascha Sommer | ```
/** check for packet loss */
``` |

1496 | ```
if (!s->packet_loss &&
``` |
||

1497 | ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) { |
||

1498 | ```
s->packet_loss = 1;
``` |
||

1499 | ```
av_log(avctx, AV_LOG_ERROR, "Packet loss detected! seq %x vs %x\n",
``` |
||

1500 | s->packet_sequence_number, packet_sequence_number); |
||

1501 | } |
||

1502 | s->packet_sequence_number = packet_sequence_number; |
||

1503 | |||

1504 | if (num_bits_prev_frame > 0) { |
||

1505 | ```
/** append the previous frame data to the remaining data from the
``` |
||

1506 | ```
previous packet to create a full frame */
``` |
||

1507 | ```
save_bits(s, gb, num_bits_prev_frame, 1);
``` |
||

1508 | ```
dprintf(avctx, "accumulated %x bits of frame data\n",
``` |
||

1509 | s->num_saved_bits - s->frame_offset); |
||

1510 | |||

1511 | ```
/** decode the cross packet frame if it is valid */
``` |
||

1512 | ```
if (!s->packet_loss)
``` |
||

1513 | decode_frame(s); |
||

1514 | } else if (s->num_saved_bits - s->frame_offset) { |
||

1515 | ```
dprintf(avctx, "ignoring %x previously saved bits\n",
``` |
||

1516 | s->num_saved_bits - s->frame_offset); |
||

1517 | } |
||

1518 | c1061cc7 | Sascha Sommer | |

1519 | 9244370a | Sascha Sommer | ```
s->packet_loss = 0;
``` |

1520 | 7551a559 | Sascha Sommer | |

1521 | ```
} else {
``` |
||

1522 | 5f28b5e7 | Sascha Sommer | ```
int frame_size;
``` |

1523 | bc7f96b1 | Sascha Sommer | ```
s->buf_bit_size = avpkt->size << 3;
``` |

1524 | init_get_bits(gb, avpkt->data, s->buf_bit_size); |
||

1525 | skip_bits(gb, s->packet_offset); |
||

1526 | 5f28b5e7 | Sascha Sommer | ```
if (remaining_bits(s, gb) > s->log2_frame_size &&
``` |

1527 | (frame_size = show_bits(gb, s->log2_frame_size)) && |
||

1528 | frame_size <= remaining_bits(s, gb)) { |
||

1529 | 20169324 | Sascha Sommer | ```
save_bits(s, gb, frame_size, 0);
``` |

1530 | 5f28b5e7 | Sascha Sommer | s->packet_done = !decode_frame(s); |

1531 | c1061cc7 | Sascha Sommer | ```
} else
``` |

1532 | 5f28b5e7 | Sascha Sommer | ```
s->packet_done = 1;
``` |

1533 | c1061cc7 | Sascha Sommer | } |

1534 | |||

1535 | 5f28b5e7 | Sascha Sommer | ```
if (s->packet_done && !s->packet_loss &&
``` |

1536 | 7551a559 | Sascha Sommer | ```
remaining_bits(s, gb) > 0) {
``` |

1537 | c1061cc7 | Sascha Sommer | ```
/** save the rest of the data so that it can be decoded
``` |

1538 | ```
with the next packet */
``` |
||

1539 | 20169324 | Sascha Sommer | ```
save_bits(s, gb, remaining_bits(s, gb), 0);
``` |

1540 | c1061cc7 | Sascha Sommer | } |

1541 | |||

1542 | *data_size = (int8_t *)s->samples - (int8_t *)data; |
||

1543 | bc7f96b1 | Sascha Sommer | ```
s->packet_offset = get_bits_count(gb) & 7;
``` |

1544 | c1061cc7 | Sascha Sommer | |

1545 | 037396d0 | Sascha Sommer | return (s->packet_loss) ? AVERROR_INVALIDDATA : get_bits_count(gb) >> 3; |

1546 | c1061cc7 | Sascha Sommer | } |

1547 | |||

1548 | ```
/**
``` |
||

1549 | ```
*@brief Clear decoder buffers (for seeking).
``` |
||

1550 | ```
*@param avctx codec context
``` |
||

1551 | ```
*/
``` |
||

1552 | static void flush(AVCodecContext *avctx) |
||

1553 | { |
||

1554 | WMAProDecodeCtx *s = avctx->priv_data; |
||

1555 | ```
int i;
``` |
||

1556 | ```
/** reset output buffer as a part of it is used during the windowing of a
``` |
||

1557 | ```
new frame */
``` |
||

1558 | for (i = 0; i < s->num_channels; i++) |
||

1559 | ```
memset(s->channel[i].out, 0, s->samples_per_frame *
``` |
||

1560 | ```
sizeof(*s->channel[i].out));
``` |
||

1561 | ```
s->packet_loss = 1;
``` |
||

1562 | } |
||

1563 | |||

1564 | |||

1565 | ```
/**
``` |
||

1566 | ```
*@brief wmapro decoder
``` |
||

1567 | ```
*/
``` |
||

1568 | AVCodec wmapro_decoder = { |
||

1569 | ```
"wmapro",
``` |
||

1570 | CODEC_TYPE_AUDIO, |
||

1571 | CODEC_ID_WMAPRO, |
||

1572 | ```
sizeof(WMAProDecodeCtx),
``` |
||

1573 | decode_init, |
||

1574 | ```
NULL,
``` |
||

1575 | decode_end, |
||

1576 | decode_packet, |
||

1577 | d859bb1d | Sascha Sommer | .capabilities = CODEC_CAP_SUBFRAMES, |

1578 | c1061cc7 | Sascha Sommer | .flush= flush, |

1579 | ```
.long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 9 Professional"),
``` |
||

1580 | }; |