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/*
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 * WMA compatible codec
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 * Copyright (c) 2002-2007 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 02110-1301 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 "bitstream.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+VLCBITS-1)/VLCBITS)
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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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    uint16_t *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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    int16_t 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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    MDCTContext 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_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_wma_scale_huffcodes[121];
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extern const uint8_t ff_wma_scale_huffbits[121];
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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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#endif /* AVCODEC_WMA_H */