ffmpeg / libavcodec / wma.h @ 84dc2d8a
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/*


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* WMA compatible codec

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* Copyright (c) 20022007 The FFmpeg Project

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*

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* This file is part of FFmpeg.

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*

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* FFmpeg is free software; you can redistribute it and/or

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* modify it under the terms of the GNU Lesser General Public

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* License as published by the Free Software Foundation; either

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* version 2.1 of the License, or (at your option) any later version.

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*

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* FFmpeg is distributed in the hope that it will be useful,

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* but WITHOUT ANY WARRANTY; without even the implied warranty of

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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

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* Lesser General Public License for more details.

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*

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* You should have received a copy of the GNU Lesser General Public

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* License along with FFmpeg; if not, write to the Free Software

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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 021101301 USA

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*/

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#ifndef AVCODEC_WMA_H

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#define AVCODEC_WMA_H

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#include "get_bits.h" 
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#include "put_bits.h" 
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#include "dsputil.h" 
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/* size of blocks */

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#define BLOCK_MIN_BITS 7 
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#define BLOCK_MAX_BITS 11 
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#define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS) 
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#define BLOCK_NB_SIZES (BLOCK_MAX_BITS  BLOCK_MIN_BITS + 1) 
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/* XXX: find exact max size */

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#define HIGH_BAND_MAX_SIZE 16 
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#define NB_LSP_COEFS 10 
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/* XXX: is it a suitable value ? */

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#define MAX_CODED_SUPERFRAME_SIZE 16384 
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#define MAX_CHANNELS 2 
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#define NOISE_TAB_SIZE 8192 
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#define LSP_POW_BITS 7 
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//FIXME should be in wmadec

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#define VLCBITS 9 
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#define VLCMAX ((22+VLCBITS1)/VLCBITS) 
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typedef float WMACoef; ///< type for decoded coefficients, int16_t would be enough for wma 1/2 
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typedef struct CoefVLCTable { 
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int n; ///< total number of codes 
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int max_level;

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const uint32_t *huffcodes; ///< VLC bit values 
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const uint8_t *huffbits; ///< VLC bit size 
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const uint16_t *levels; ///< table to build run/level tables 
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} CoefVLCTable; 
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typedef struct WMACodecContext { 
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AVCodecContext* avctx; 
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GetBitContext gb; 
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PutBitContext pb; 
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int sample_rate;

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int nb_channels;

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int bit_rate;

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int version; ///< 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2) 
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int block_align;

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int use_bit_reservoir;

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int use_variable_block_len;

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int use_exp_vlc; ///< exponent coding: 0 = lsp, 1 = vlc + delta 
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int use_noise_coding; ///< true if perceptual noise is added 
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int byte_offset_bits;

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VLC exp_vlc; 
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int exponent_sizes[BLOCK_NB_SIZES];

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uint16_t exponent_bands[BLOCK_NB_SIZES][25];

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int high_band_start[BLOCK_NB_SIZES]; ///< index of first coef in high band 
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int coefs_start; ///< first coded coef 
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int coefs_end[BLOCK_NB_SIZES]; ///< max number of coded coefficients 
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int exponent_high_sizes[BLOCK_NB_SIZES];

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int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];

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VLC hgain_vlc; 
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/* coded values in high bands */

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int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];

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int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];

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/* there are two possible tables for spectral coefficients */

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//FIXME the following 3 tables should be shared between decoders

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VLC coef_vlc[2];

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uint16_t *run_table[2];

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float *level_table[2]; 
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uint16_t *int_table[2];

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const CoefVLCTable *coef_vlcs[2]; 
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/* frame info */

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int frame_len; ///< frame length in samples 
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int frame_len_bits; ///< frame_len = 1 << frame_len_bits 
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int nb_block_sizes; ///< number of block sizes 
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/* block info */

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int reset_block_lengths;

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int block_len_bits; ///< log2 of current block length 
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int next_block_len_bits; ///< log2 of next block length 
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int prev_block_len_bits; ///< log2 of prev block length 
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int block_len; ///< block length in samples 
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int block_num; ///< block number in current frame 
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int block_pos; ///< current position in frame 
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uint8_t ms_stereo; ///< true if mid/side stereo mode

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uint8_t channel_coded[MAX_CHANNELS]; ///< true if channel is coded

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int exponents_bsize[MAX_CHANNELS]; ///< log2 ratio frame/exp. length 
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DECLARE_ALIGNED(16, float, exponents)[MAX_CHANNELS][BLOCK_MAX_SIZE]; 
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float max_exponent[MAX_CHANNELS];

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WMACoef coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE]; 
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DECLARE_ALIGNED(16, float, coefs)[MAX_CHANNELS][BLOCK_MAX_SIZE]; 
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DECLARE_ALIGNED(16, FFTSample, output)[BLOCK_MAX_SIZE * 2]; 
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FFTContext mdct_ctx[BLOCK_NB_SIZES]; 
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float *windows[BLOCK_NB_SIZES];

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/* output buffer for one frame and the last for IMDCT windowing */

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DECLARE_ALIGNED(16, float, frame_out)[MAX_CHANNELS][BLOCK_MAX_SIZE * 2]; 
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/* last frame info */

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uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */ 
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int last_bitoffset;

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int last_superframe_len;

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float noise_table[NOISE_TAB_SIZE];

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int noise_index;

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float noise_mult; /* XXX: suppress that and integrate it in the noise array */ 
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/* lsp_to_curve tables */

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float lsp_cos_table[BLOCK_MAX_SIZE];

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float lsp_pow_e_table[256]; 
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float lsp_pow_m_table1[(1 << LSP_POW_BITS)]; 
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float lsp_pow_m_table2[(1 << LSP_POW_BITS)]; 
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DSPContext dsp; 
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#ifdef TRACE

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int frame_count;

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#endif

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} WMACodecContext; 
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extern const uint16_t ff_wma_critical_freqs[25]; 
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extern const uint16_t ff_wma_hgain_huffcodes[37]; 
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extern const uint8_t ff_wma_hgain_huffbits[37]; 
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extern const float ff_wma_lsp_codebook[NB_LSP_COEFS][16]; 
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extern const uint32_t ff_aac_scalefactor_code[121]; 
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extern const uint8_t ff_aac_scalefactor_bits[121]; 
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int av_cold ff_wma_get_frame_len_bits(int sample_rate, int version, 
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unsigned int decode_flags); 
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int ff_wma_init(AVCodecContext * avctx, int flags2); 
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int ff_wma_total_gain_to_bits(int total_gain); 
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int ff_wma_end(AVCodecContext *avctx);

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unsigned int ff_wma_get_large_val(GetBitContext* gb); 
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int ff_wma_run_level_decode(AVCodecContext* avctx, GetBitContext* gb,

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VLC *vlc, 
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const float *level_table, const uint16_t *run_table, 
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int version, WMACoef *ptr, int offset, 
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int num_coefs, int block_len, int frame_len_bits, 
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int coef_nb_bits);

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#endif /* AVCODEC_WMA_H */ 