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/*
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 * TwinVQ decoder
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 * Copyright (c) 2009 Vitor Sessak
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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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#include "avcodec.h"
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#include "get_bits.h"
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#include "dsputil.h"
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#include <math.h>
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#include <stdint.h>
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#include "twinvq_data.h"
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enum FrameType {
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    FT_SHORT = 0,  ///< Short frame  (divided in n   sub-blocks)
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    FT_MEDIUM,     ///< Medium frame (divided in m<n sub-blocks)
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    FT_LONG,       ///< Long frame   (single sub-block + PPC)
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    FT_PPC,        ///< Periodic Peak Component (part of the long frame)
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};
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/**
39
 * Parameters and tables that are different for each frame type
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 */
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struct FrameMode {
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    uint8_t         sub;      ///< Number subblocks in each frame
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    const uint16_t *bark_tab;
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    /** number of distinct bark scale envelope values */
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    uint8_t         bark_env_size;
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    const int16_t  *bark_cb;    ///< codebook for the bark scale envelope (BSE)
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    uint8_t         bark_n_coef;///< number of BSE CB coefficients to read
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    uint8_t         bark_n_bit; ///< number of bits of the BSE coefs
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    //@{
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    /** main codebooks for spectrum data */
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    const int16_t    *cb0;
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    const int16_t    *cb1;
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    //@}
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    uint8_t         cb_len_read; ///< number of spectrum coefficients to read
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};
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/**
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 * Parameters and tables that are different for every combination of
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 * bitrate/sample rate
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 */
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typedef struct {
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    struct FrameMode fmode[3]; ///< frame type-dependant parameters
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    uint16_t     size;        ///< frame size in samples
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    uint8_t      n_lsp;       ///< number of lsp coefficients
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    const float *lspcodebook;
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    /* number of bits of the different LSP CB coefficients */
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    uint8_t      lsp_bit0;
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    uint8_t      lsp_bit1;
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    uint8_t      lsp_bit2;
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    uint8_t      lsp_split;      ///< number of CB entries for the LSP decoding
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    const int16_t *ppc_shape_cb; ///< PPC shape CB
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    /** number of the bits for the PPC period value */
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    uint8_t      ppc_period_bit;
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    uint8_t      ppc_shape_bit;  ///< number of bits of the PPC shape CB coeffs
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    uint8_t      ppc_shape_len;  ///< size of PPC shape CB
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    uint8_t      pgain_bit;      ///< bits for PPC gain
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    /** constant for peak period to peak width conversion */
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    uint16_t     peak_per2wid;
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} ModeTab;
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static const ModeTab mode_08_08 = {
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    {
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        { 8, bark_tab_s08_64,  10, tab.fcb08s  , 1, 5, tab.cb0808s0, tab.cb0808s1, 18},
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        { 2, bark_tab_m08_256, 20, tab.fcb08m  , 2, 5, tab.cb0808m0, tab.cb0808m1, 16},
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        { 1, bark_tab_l08_512, 30, tab.fcb08l  , 3, 6, tab.cb0808l0, tab.cb0808l1, 17}
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    },
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    512 , 12, tab.lsp08,   1, 5, 3, 3, tab.shape08  , 8, 28, 20, 6, 40
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};
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static const ModeTab mode_11_08 = {
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    {
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        { 8, bark_tab_s11_64,  10, tab.fcb11s  , 1, 5, tab.cb1108s0, tab.cb1108s1, 29},
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        { 2, bark_tab_m11_256, 20, tab.fcb11m  , 2, 5, tab.cb1108m0, tab.cb1108m1, 24},
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        { 1, bark_tab_l11_512, 30, tab.fcb11l  , 3, 6, tab.cb1108l0, tab.cb1108l1, 27}
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    },
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    512 , 16, tab.lsp11,   1, 6, 4, 3, tab.shape11  , 9, 36, 30, 7, 90
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};
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static const ModeTab mode_11_10 = {
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    {
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        { 8, bark_tab_s11_64,  10, tab.fcb11s  , 1, 5, tab.cb1110s0, tab.cb1110s1, 21},
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        { 2, bark_tab_m11_256, 20, tab.fcb11m  , 2, 5, tab.cb1110m0, tab.cb1110m1, 18},
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        { 1, bark_tab_l11_512, 30, tab.fcb11l  , 3, 6, tab.cb1110l0, tab.cb1110l1, 20}
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    },
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    512 , 16, tab.lsp11,   1, 6, 4, 3, tab.shape11  , 9, 36, 30, 7, 90
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};
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static const ModeTab mode_16_16 = {
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    {
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        { 8, bark_tab_s16_128, 10, tab.fcb16s  , 1, 5, tab.cb1616s0, tab.cb1616s1, 16},
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        { 2, bark_tab_m16_512, 20, tab.fcb16m  , 2, 5, tab.cb1616m0, tab.cb1616m1, 15},
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        { 1, bark_tab_l16_1024,30, tab.fcb16l  , 3, 6, tab.cb1616l0, tab.cb1616l1, 16}
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    },
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    1024, 16, tab.lsp16,   1, 6, 4, 3, tab.shape16  , 9, 56, 60, 7, 180
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};
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static const ModeTab mode_22_20 = {
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    {
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        { 8, bark_tab_s22_128, 10, tab.fcb22s_1, 1, 6, tab.cb2220s0, tab.cb2220s1, 18},
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        { 2, bark_tab_m22_512, 20, tab.fcb22m_1, 2, 6, tab.cb2220m0, tab.cb2220m1, 17},
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        { 1, bark_tab_l22_1024,32, tab.fcb22l_1, 4, 6, tab.cb2220l0, tab.cb2220l1, 18}
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    },
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    1024, 16, tab.lsp22_1, 1, 6, 4, 3, tab.shape22_1, 9, 56, 36, 7, 144
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};
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static const ModeTab mode_22_24 = {
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    {
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        { 8, bark_tab_s22_128, 10, tab.fcb22s_1, 1, 6, tab.cb2224s0, tab.cb2224s1, 15},
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        { 2, bark_tab_m22_512, 20, tab.fcb22m_1, 2, 6, tab.cb2224m0, tab.cb2224m1, 14},
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        { 1, bark_tab_l22_1024,32, tab.fcb22l_1, 4, 6, tab.cb2224l0, tab.cb2224l1, 15}
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    },
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    1024, 16, tab.lsp22_1, 1, 6, 4, 3, tab.shape22_1, 9, 56, 36, 7, 144
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};
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static const ModeTab mode_22_32 = {
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    {
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        { 4, bark_tab_s22_128, 10, tab.fcb22s_2, 1, 6, tab.cb2232s0, tab.cb2232s1, 11},
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        { 2, bark_tab_m22_256, 20, tab.fcb22m_2, 2, 6, tab.cb2232m0, tab.cb2232m1, 11},
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        { 1, bark_tab_l22_512, 32, tab.fcb22l_2, 4, 6, tab.cb2232l0, tab.cb2232l1, 12}
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    },
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    512 , 16, tab.lsp22_2, 1, 6, 4, 4, tab.shape22_2, 9, 56, 36, 7, 72
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};
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static const ModeTab mode_44_40 = {
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    {
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        {16, bark_tab_s44_128, 10, tab.fcb44s  , 1, 6, tab.cb4440s0, tab.cb4440s1, 18},
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        { 4, bark_tab_m44_512, 20, tab.fcb44m  , 2, 6, tab.cb4440m0, tab.cb4440m1, 17},
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        { 1, bark_tab_l44_2048,40, tab.fcb44l  , 4, 6, tab.cb4440l0, tab.cb4440l1, 17}
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    },
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    2048, 20, tab.lsp44,   1, 6, 4, 4, tab.shape44  , 9, 84, 54, 7, 432
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};
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static const ModeTab mode_44_48 = {
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    {
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        {16, bark_tab_s44_128, 10, tab.fcb44s  , 1, 6, tab.cb4448s0, tab.cb4448s1, 15},
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        { 4, bark_tab_m44_512, 20, tab.fcb44m  , 2, 6, tab.cb4448m0, tab.cb4448m1, 14},
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        { 1, bark_tab_l44_2048,40, tab.fcb44l  , 4, 6, tab.cb4448l0, tab.cb4448l1, 14}
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    },
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    2048, 20, tab.lsp44,   1, 6, 4, 4, tab.shape44  , 9, 84, 54, 7, 432
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};
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typedef struct TwinContext {
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    AVCodecContext *avctx;
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    DSPContext      dsp;
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    MDCTContext mdct_ctx[3];
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177
    const ModeTab *mtab;
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    // history
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    float lsp_hist[2][20];           ///< LSP coefficients of the last frame
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    float bark_hist[3][2][40];       ///< BSE coefficients of last frame
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    // bitstream parameters
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    int16_t permut[4][4096];
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    uint8_t length[4][2];            ///< main codebook stride
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    uint8_t length_change[4];
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    uint8_t bits_main_spec[2][4][2]; ///< bits for the main codebook
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    int bits_main_spec_change[4];
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    int n_div[4];
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191
    float *spectrum;
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    float *curr_frame;               ///< non-interleaved output
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    float *prev_frame;               ///< non-interleaved previous frame
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    int last_block_pos[2];
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196
    float *cos_tabs[3];
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    // scratch buffers
199
    float *tmp_buf;
200
} TwinContext;
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202
#define PPC_SHAPE_CB_SIZE 64
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#define SUB_AMP_MAX       4500.0
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#define MULAW_MU          100.0
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#define GAIN_BITS         8
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#define AMP_MAX           13000.0
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#define SUB_GAIN_BITS     5
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#define WINDOW_TYPE_BITS  4
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#define PGAIN_MU          200
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211
/** @note not speed critical, hence not optimized */
212
static void memset_float(float *buf, float val, int size)
213
{
214
    while (size--)
215
        *buf++ = val;
216
}
217

    
218
/**
219
 * Evaluate a single LPC amplitude spectrum envelope coefficient from the line
220
 * spectrum pairs.
221
 *
222
 * @param lsp a vector of the cosinus of the LSP values
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 * @param cos_val cos(PI*i/N) where i is the index of the LPC amplitude
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 * @param order the order of the LSP (and the size of the *lsp buffer). Must
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 *        be a multiple of four.
226
 * @return the LPC value
227
 *
228
 * @todo reuse code from vorbis_dec.c: vorbis_floor0_decode
229
 */
230
static float eval_lpc_spectrum(const float *lsp, float cos_val, int order)
231
{
232
    int j;
233
    float p = 0.5f;
234
    float q = 0.5f;
235
    float two_cos_w = 2.0f*cos_val;
236

    
237
    for (j=0; j + 1 < order; j += 2*2) {
238
        // Unroll the loop once since order is a multiple of four
239
        q *= lsp[j  ] - two_cos_w;
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        p *= lsp[j+1] - two_cos_w;
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242
        q *= lsp[j+2] - two_cos_w;
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        p *= lsp[j+3] - two_cos_w;
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    }
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246
    p *= p * (2.0f - two_cos_w);
247
    q *= q * (2.0f + two_cos_w);
248

    
249
    return 0.5 / (p + q);
250
}
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252
/**
253
 * Evaluates the LPC amplitude spectrum envelope from the line spectrum pairs.
254
 */
255
static void eval_lpcenv(TwinContext *tctx, const float *cos_vals, float *lpc)
256
{
257
    int i;
258
    const ModeTab *mtab = tctx->mtab;
259
    int size_s = mtab->size / mtab->fmode[FT_SHORT].sub;
260

    
261
    for (i=0; i < size_s/2; i++) {
262
        float cos_i = tctx->cos_tabs[0][i];
263
        lpc[i]          = eval_lpc_spectrum(cos_vals,  cos_i, mtab->n_lsp);
264
        lpc[size_s-i-1] = eval_lpc_spectrum(cos_vals, -cos_i, mtab->n_lsp);
265
    }
266
}
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268
static void interpolate(float *out, float v1, float v2, int size)
269
{
270
    int i;
271
    float step = (v1 - v2)/(size + 1);
272

    
273
    for (i=0; i < size; i++) {
274
        v2 += step;
275
        out[i] = v2;
276
    }
277
}
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279
static inline float get_cos(int idx, int part, const float *cos_tab, int size)
280
{
281
    return part ? -cos_tab[size - idx - 1] :
282
                   cos_tab[       idx    ];
283
}
284

    
285
/**
286
 * Evaluates the LPC amplitude spectrum envelope from the line spectrum pairs.
287
 * Probably for speed reasons, the coefficients are evaluated as
288
 * siiiibiiiisiiiibiiiisiiiibiiiisiiiibiiiis ...
289
 * where s is an evaluated value, i is a value interpolated from the others
290
 * and b might be either calculated or interpolated, depending on an
291
 * unexplained condition.
292
 *
293
 * @param step the size of a block "siiiibiiii"
294
 * @param in the cosinus of the LSP data
295
 * @param part is 0 for 0...PI (positive cossinus values) and 1 for PI...2PI
296
          (negative cossinus values)
297
 * @param size the size of the whole output
298
 */
299
static inline void eval_lpcenv_or_interp(TwinContext *tctx,
300
                                         enum FrameType ftype,
301
                                         float *out, const float *in,
302
                                         int size, int step, int part)
303
{
304
    int i;
305
    const ModeTab *mtab = tctx->mtab;
306
    const float *cos_tab = tctx->cos_tabs[ftype];
307

    
308
    // Fill the 's'
309
    for (i=0; i < size; i += step)
310
        out[i] =
311
            eval_lpc_spectrum(in,
312
                              get_cos(i, part, cos_tab, size),
313
                              mtab->n_lsp);
314

    
315
    // Fill the 'iiiibiiii'
316
    for (i=step; i <= size - 2*step; i += step) {
317
        if (out[i + step] + out[i - step] >  1.95*out[i] ||
318
            out[i + step]                 >=  out[i - step]) {
319
            interpolate(out + i - step + 1, out[i], out[i-step], step - 1);
320
        } else {
321
            out[i - step/2] =
322
                eval_lpc_spectrum(in,
323
                                  get_cos(i-step/2, part, cos_tab, size),
324
                                  mtab->n_lsp);
325
            interpolate(out + i - step   + 1, out[i-step/2], out[i-step  ], step/2 - 1);
326
            interpolate(out + i - step/2 + 1, out[i       ], out[i-step/2], step/2 - 1);
327
        }
328
    }
329

    
330
    interpolate(out + size - 2*step + 1, out[size-step], out[size - 2*step], step - 1);
331
}
332

    
333
static void eval_lpcenv_2parts(TwinContext *tctx, enum FrameType ftype,
334
                               const float *buf, float *lpc,
335
                               int size, int step)
336
{
337
    eval_lpcenv_or_interp(tctx, ftype, lpc         , buf, size/2,   step, 0);
338
    eval_lpcenv_or_interp(tctx, ftype, lpc + size/2, buf, size/2, 2*step, 1);
339

    
340
    interpolate(lpc+size/2-step+1, lpc[size/2], lpc[size/2-step], step);
341

    
342
    memset_float(lpc + size - 2*step + 1, lpc[size - 2*step], 2*step - 1);
343
}
344

    
345
/**
346
 * Inverse quantization. Read CB coefficients for cb1 and cb2 from the
347
 * bitstream, sum the corresponding vectors and write the result to *out
348
 * after permutation.
349
 */
350
static void dequant(TwinContext *tctx, GetBitContext *gb, float *out,
351
                    enum FrameType ftype,
352
                    const int16_t *cb0, const int16_t *cb1, int cb_len)
353
{
354
    int pos = 0;
355
    int i, j;
356

    
357
    for (i=0; i < tctx->n_div[ftype]; i++) {
358
        int tmp0, tmp1;
359
        int sign0 = 1;
360
        int sign1 = 1;
361
        const int16_t *tab0, *tab1;
362
        int length = tctx->length[ftype][i >= tctx->length_change[ftype]];
363
        int bitstream_second_part = (i >= tctx->bits_main_spec_change[ftype]);
364

    
365
        int bits = tctx->bits_main_spec[0][ftype][bitstream_second_part];
366
        if (bits == 7) {
367
            if (get_bits1(gb))
368
                sign0 = -1;
369
            bits = 6;
370
        }
371
        tmp0 = get_bits(gb, bits);
372

    
373
        bits = tctx->bits_main_spec[1][ftype][bitstream_second_part];
374

    
375
        if (bits == 7) {
376
            if (get_bits1(gb))
377
                sign1 = -1;
378

    
379
            bits = 6;
380
        }
381
        tmp1 = get_bits(gb, bits);
382

    
383
        tab0 = cb0 + tmp0*cb_len;
384
        tab1 = cb1 + tmp1*cb_len;
385

    
386
        for (j=0; j < length; j++)
387
            out[tctx->permut[ftype][pos+j]] = sign0*tab0[j] + sign1*tab1[j];
388

    
389
        pos += length;
390
    }
391

    
392
}
393

    
394
static inline float mulawinv(float y, float clip, float mu)
395
{
396
    y = av_clipf(y/clip, -1, 1);
397
    return clip * FFSIGN(y) * (exp(log(1+mu) * fabs(y)) - 1) / mu;
398
}
399

    
400
/**
401
 * Evaluate a*b/400 rounded to the nearest integer. When, for example,
402
 * a*b == 200 and the nearest integer is ill-defined, use a table to emulate
403
 * the following broken float-based implementation used by the binary decoder:
404
 *
405
 * \code
406
 * static int very_broken_op(int a, int b)
407
 * {
408
 *    static float test; // Ugh, force gcc to do the division first...
409
 *
410
 *    test = a/400.;
411
 *    return b * test +  0.5;
412
 * }
413
 * \endcode
414
 *
415
 * @note if this function is replaced by just ROUNDED_DIV(a*b,400.), the stddev
416
 * between the original file (before encoding with Yamaha encoder) and the
417
 * decoded output increases, which leads one to believe that the encoder expects
418
 * exactly this broken calculation.
419
 */
420
static int very_broken_op(int a, int b)
421
{
422
    int x = a*b + 200;
423
    int size;
424
    const uint8_t *rtab;
425

    
426
    if (x%400 || b%5)
427
        return x/400;
428

    
429
    x /= 400;
430

    
431
    size = tabs[b/5].size;
432
    rtab = tabs[b/5].tab;
433
    return x - rtab[size*av_log2(2*(x - 1)/size)+(x - 1)%size];
434
}
435

    
436
/**
437
 * Sum to data a periodic peak of a given period, width and shape.
438
 *
439
 * @param period the period of the peak divised by 400.0
440
 */
441
static void add_peak(int period, int width, const float *shape,
442
                     float ppc_gain, float *speech, int len)
443
{
444
    int i, j;
445

    
446
    const float *shape_end = shape + len;
447
    int center;
448

    
449
    // First peak centered around zero
450
    for (i=0; i < width/2; i++)
451
        speech[i] += ppc_gain * *shape++;
452

    
453
    for (i=1; i < ROUNDED_DIV(len,width) ; i++) {
454
        center = very_broken_op(period, i);
455
        for (j=-width/2; j < (width+1)/2; j++)
456
            speech[j+center] += ppc_gain * *shape++;
457
    }
458

    
459
    // For the last block, be careful not to go beyond the end of the buffer
460
    center = very_broken_op(period, i);
461
    for (j=-width/2; j < (width + 1)/2 && shape < shape_end; j++)
462
        speech[j+center] += ppc_gain * *shape++;
463
}
464

    
465
static void decode_ppc(TwinContext *tctx, int period_coef, const float *shape,
466
                       float ppc_gain, float *speech)
467
{
468
    const ModeTab *mtab = tctx->mtab;
469
    int isampf = tctx->avctx->sample_rate/1000;
470
    int ibps = tctx->avctx->bit_rate/(1000 * tctx->avctx->channels);
471
    int min_period = ROUNDED_DIV(  40*2*mtab->size, isampf);
472
    int max_period = ROUNDED_DIV(6*40*2*mtab->size, isampf);
473
    int period_range = max_period - min_period;
474

    
475
    // This is actually the period multiplied by 400. It is just linearly coded
476
    // between its maximum and minimum value.
477
    int period = min_period +
478
        ROUNDED_DIV(period_coef*period_range, (1 << mtab->ppc_period_bit) - 1);
479
    int width;
480

    
481
    if (isampf == 22 && ibps == 32) {
482
        // For some unknown reason, NTT decided to code this case differently...
483
        width = ROUNDED_DIV((period + 800)* mtab->peak_per2wid, 400*mtab->size);
484
    } else
485
        width =             (period      )* mtab->peak_per2wid/(400*mtab->size);
486

    
487
    add_peak(period, width, shape, ppc_gain, speech, mtab->ppc_shape_len);
488
}
489

    
490
static void dec_gain(TwinContext *tctx, GetBitContext *gb, enum FrameType ftype,
491
                     float *out)
492
{
493
    const ModeTab *mtab = tctx->mtab;
494
    int i, j;
495
    int sub = mtab->fmode[ftype].sub;
496
    float step     = AMP_MAX     / ((1 <<     GAIN_BITS) - 1);
497
    float sub_step = SUB_AMP_MAX / ((1 << SUB_GAIN_BITS) - 1);
498

    
499
    if (ftype == FT_LONG) {
500
        for (i=0; i < tctx->avctx->channels; i++)
501
            out[i] = (1./(1<<13)) *
502
                mulawinv(step * 0.5 + step * get_bits(gb, GAIN_BITS),
503
                         AMP_MAX, MULAW_MU);
504
    } else {
505
        for (i=0; i < tctx->avctx->channels; i++) {
506
            float val = (1./(1<<23)) *
507
                mulawinv(step * 0.5 + step * get_bits(gb, GAIN_BITS),
508
                         AMP_MAX, MULAW_MU);
509

    
510
            for (j=0; j < sub; j++) {
511
                out[i*sub + j] =
512
                    val*mulawinv(sub_step* 0.5 +
513
                                 sub_step* get_bits(gb, SUB_GAIN_BITS),
514
                                 SUB_AMP_MAX, MULAW_MU);
515
            }
516
        }
517
    }
518
}
519

    
520
/**
521
 * Rearrange the LSP coefficients so that they have a minimum distance of
522
 * min_dist. This function does it exactly as described in section of 3.2.4
523
 * of the G.729 specification (but interestingly is different from what the
524
 * reference decoder actually does).
525
 */
526
static void rearrange_lsp(int order, float *lsp, float min_dist)
527
{
528
    int i;
529
    float min_dist2 = min_dist * 0.5;
530
    for (i=1; i < order; i++)
531
        if (lsp[i] - lsp[i-1] < min_dist) {
532
            float avg = (lsp[i] + lsp[i-1]) * 0.5;
533

    
534
            lsp[i-1] = avg - min_dist2;
535
            lsp[i  ] = avg + min_dist2;
536
        }
537
}
538

    
539
static void bubblesort(float *lsp, int lp_order)
540
{
541
    int i,j;
542

    
543
    /* sort lsp in ascending order. float bubble agorithm,
544
       O(n) if data already sorted, O(n^2) - otherwise */
545
    for (i=0; i < lp_order - 1; i++)
546
        for (j=i; j >= 0 && lsp[j] > lsp[j+1]; j--)
547
            FFSWAP(float, lsp[j], lsp[j+1]);
548
}
549

    
550
static void decode_lsp(TwinContext *tctx, int lpc_idx1, uint8_t *lpc_idx2,
551
                       int lpc_hist_idx, float *lsp, float *hist)
552
{
553
    const ModeTab *mtab = tctx->mtab;
554
    int i, j;
555

    
556
    const float *cb  =  mtab->lspcodebook;
557
    const float *cb2 =  cb  + (1 << mtab->lsp_bit1)*mtab->n_lsp;
558
    const float *cb3 =  cb2 + (1 << mtab->lsp_bit2)*mtab->n_lsp;
559

    
560
    const int8_t funny_rounding[4] = {
561
        -2,
562
        mtab->lsp_split == 4 ? -2 : 1,
563
        mtab->lsp_split == 4 ? -2 : 1,
564
        0
565
    };
566

    
567
    j=0;
568
    for (i=0; i < mtab->lsp_split; i++) {
569
        int chunk_end = ((i + 1)*mtab->n_lsp + funny_rounding[i])/mtab->lsp_split;
570
        for (; j < chunk_end; j++)
571
            lsp[j] = cb [lpc_idx1    * mtab->n_lsp + j] +
572
                     cb2[lpc_idx2[i] * mtab->n_lsp + j];
573
    }
574

    
575
    rearrange_lsp(mtab->n_lsp, lsp, 0.0001);
576

    
577
    for (i=0; i < mtab->n_lsp; i++) {
578
        float tmp1 = 1. -          cb3[lpc_hist_idx*mtab->n_lsp + i];
579
        float tmp2 =     hist[i] * cb3[lpc_hist_idx*mtab->n_lsp + i];
580
        hist[i] = lsp[i];
581
        lsp[i]  = lsp[i] * tmp1 + tmp2;
582
    }
583

    
584
    rearrange_lsp(mtab->n_lsp, lsp, 0.0001);
585
    rearrange_lsp(mtab->n_lsp, lsp, 0.000095);
586
    bubblesort(lsp, mtab->n_lsp);
587
}
588

    
589
static void dec_lpc_spectrum_inv(TwinContext *tctx, float *lsp,
590
                                 enum FrameType ftype, float *lpc)
591
{
592
    int i;
593
    int size = tctx->mtab->size / tctx->mtab->fmode[ftype].sub;
594

    
595
    for (i=0; i < tctx->mtab->n_lsp; i++)
596
        lsp[i] =  2*cos(lsp[i]);
597

    
598
    switch (ftype) {
599
    case FT_LONG:
600
        eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 8);
601
        break;
602
    case FT_MEDIUM:
603
        eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 2);
604
        break;
605
    case FT_SHORT:
606
        eval_lpcenv(tctx, lsp, lpc);
607
        break;
608
    }
609
}
610

    
611
static void imdct_and_window(TwinContext *tctx, enum FrameType ftype, int wtype,
612
                            float *in, float *prev, int ch)
613
{
614
    const ModeTab *mtab = tctx->mtab;
615
    int bsize = mtab->size / mtab->fmode[ftype].sub;
616
    int size  = mtab->size;
617
    float *buf1 = tctx->tmp_buf;
618
    int j;
619
    int wsize; // Window size
620
    float *out = tctx->curr_frame + 2*ch*mtab->size;
621
    float *out2 = out;
622
    float *prev_buf;
623
    int first_wsize;
624

    
625
    static const uint8_t wtype_to_wsize[]      = {0, 0, 2, 2, 2, 1, 0, 1, 1};
626
    int types_sizes[] = {
627
        mtab->size /    mtab->fmode[FT_LONG  ].sub,
628
        mtab->size /    mtab->fmode[FT_MEDIUM].sub,
629
        mtab->size / (2*mtab->fmode[FT_SHORT ].sub),
630
    };
631

    
632
    wsize = types_sizes[wtype_to_wsize[wtype]];
633
    first_wsize = wsize;
634
    prev_buf = prev + (size - bsize)/2;
635

    
636
    for (j=0; j < mtab->fmode[ftype].sub; j++) {
637
        int sub_wtype = ftype == FT_MEDIUM ? 8 : wtype;
638

    
639
        if (!j && wtype == 4)
640
            sub_wtype = 4;
641
        else if (j == mtab->fmode[ftype].sub-1 && wtype == 7)
642
            sub_wtype = 7;
643

    
644
        wsize = types_sizes[wtype_to_wsize[sub_wtype]];
645

    
646
        ff_imdct_half(&tctx->mdct_ctx[ftype], buf1 + bsize*j, in + bsize*j);
647

    
648
        tctx->dsp.vector_fmul_window(out2,
649
                                     prev_buf + (bsize-wsize)/2,
650
                                     buf1 + bsize*j,
651
                                     ff_sine_windows[av_log2(wsize) - 7],
652
                                     0.0,
653
                                     wsize/2);
654
        out2 += wsize;
655

    
656
        memcpy(out2, buf1 + bsize*j + wsize/2, (bsize - wsize/2)*sizeof(float));
657

    
658
        out2 += ftype == FT_MEDIUM ? (bsize-wsize)/2 : bsize - wsize;
659

    
660
        prev_buf = buf1 + bsize*j + bsize/2;
661
    }
662

    
663
    tctx->last_block_pos[ch] = (size + first_wsize)/2;
664
}
665

    
666
static void imdct_output(TwinContext *tctx, enum FrameType ftype, int wtype,
667
                         float *out)
668
{
669
    const ModeTab *mtab = tctx->mtab;
670
    float *prev_buf = tctx->prev_frame + tctx->last_block_pos[0];
671
    int i, j;
672

    
673
    for (i=0; i < tctx->avctx->channels; i++) {
674
        imdct_and_window(tctx, ftype, wtype,
675
                         tctx->spectrum + i*mtab->size,
676
                         prev_buf + 2*i*mtab->size,
677
                         i);
678
    }
679

    
680
    if (tctx->avctx->channels == 2) {
681
        for (i=0; i < mtab->size - tctx->last_block_pos[0]; i++) {
682
            float f1 = prev_buf[               i];
683
            float f2 = prev_buf[2*mtab->size + i];
684
            out[2*i    ] = f1 + f2;
685
            out[2*i + 1] = f1 - f2;
686
        }
687
        for (j=0; i < mtab->size; j++,i++) {
688
            float f1 = tctx->curr_frame[               j];
689
            float f2 = tctx->curr_frame[2*mtab->size + j];
690
            out[2*i    ] = f1 + f2;
691
            out[2*i + 1] = f1 - f2;
692
        }
693
    } else {
694
        memcpy(out, prev_buf,
695
               (mtab->size - tctx->last_block_pos[0]) * sizeof(*out));
696

    
697
        out +=  mtab->size - tctx->last_block_pos[0];
698

    
699
        memcpy(out, tctx->curr_frame,
700
               (tctx->last_block_pos[0]) * sizeof(*out));
701
    }
702

    
703
}
704

    
705
static void dec_bark_env(TwinContext *tctx, const uint8_t *in, int use_hist,
706
                         int ch, float *out, float gain, enum FrameType ftype)
707
{
708
    const ModeTab *mtab = tctx->mtab;
709
    int i,j;
710
    float *hist = tctx->bark_hist[ftype][ch];
711
    float val = ((const float []) {0.4, 0.35, 0.28})[ftype];
712
    int bark_n_coef  = mtab->fmode[ftype].bark_n_coef;
713
    int fw_cb_len = mtab->fmode[ftype].bark_env_size / bark_n_coef;
714
    int idx = 0;
715

    
716
    for (i=0; i < fw_cb_len; i++)
717
        for (j=0; j < bark_n_coef; j++, idx++) {
718
            float tmp2 =
719
                mtab->fmode[ftype].bark_cb[fw_cb_len*in[j] + i] * (1./4096);
720
            float st = use_hist ?
721
                (1. - val) * tmp2 + val*hist[idx] + 1. : tmp2 + 1.;
722

    
723
            hist[idx] = tmp2;
724
            if (st < -1.) st = 1.;
725

    
726
            memset_float(out, st * gain, mtab->fmode[ftype].bark_tab[idx]);
727
            out += mtab->fmode[ftype].bark_tab[idx];
728
        }
729

    
730
}
731

    
732
static void read_and_decode_spectrum(TwinContext *tctx, GetBitContext *gb,
733
                                     float *out, enum FrameType ftype)
734
{
735
    const ModeTab *mtab = tctx->mtab;
736
    int channels = tctx->avctx->channels;
737
    int sub = mtab->fmode[ftype].sub;
738
    int block_size = mtab->size / sub;
739
    float gain[channels*sub];
740
    float ppc_shape[mtab->ppc_shape_len * channels * 4];
741
    uint8_t bark1[channels][sub][mtab->fmode[ftype].bark_n_coef];
742
    uint8_t bark_use_hist[channels][sub];
743

    
744
    uint8_t lpc_idx1[channels];
745
    uint8_t lpc_idx2[channels][tctx->mtab->lsp_split];
746
    uint8_t lpc_hist_idx[channels];
747

    
748
    int i, j, k;
749

    
750
    dequant(tctx, gb, out, ftype,
751
            mtab->fmode[ftype].cb0, mtab->fmode[ftype].cb1,
752
            mtab->fmode[ftype].cb_len_read);
753

    
754
    for (i=0; i < channels; i++)
755
        for (j=0; j < sub; j++)
756
            for (k=0; k < mtab->fmode[ftype].bark_n_coef; k++)
757
                bark1[i][j][k] =
758
                    get_bits(gb, mtab->fmode[ftype].bark_n_bit);
759

    
760
    for (i=0; i < channels; i++)
761
        for (j=0; j < sub; j++)
762
            bark_use_hist[i][j] = get_bits1(gb);
763

    
764
    dec_gain(tctx, gb, ftype, gain);
765

    
766
    for (i=0; i < channels; i++) {
767
        lpc_hist_idx[i] = get_bits(gb, tctx->mtab->lsp_bit0);
768
        lpc_idx1    [i] = get_bits(gb, tctx->mtab->lsp_bit1);
769

    
770
        for (j=0; j < tctx->mtab->lsp_split; j++)
771
            lpc_idx2[i][j] = get_bits(gb, tctx->mtab->lsp_bit2);
772
    }
773

    
774
    if (ftype == FT_LONG) {
775
        int cb_len_p = (tctx->n_div[3] + mtab->ppc_shape_len*channels - 1)/
776
            tctx->n_div[3];
777
        dequant(tctx, gb, ppc_shape, FT_PPC, mtab->ppc_shape_cb,
778
                mtab->ppc_shape_cb + cb_len_p*PPC_SHAPE_CB_SIZE, cb_len_p);
779
    }
780

    
781
    for (i=0; i < channels; i++) {
782
        float *chunk = out + mtab->size * i;
783
        float lsp[tctx->mtab->n_lsp];
784

    
785
        for (j=0; j < sub; j++) {
786
            dec_bark_env(tctx, bark1[i][j], bark_use_hist[i][j], i,
787
                         tctx->tmp_buf, gain[sub*i+j], ftype);
788

    
789
            tctx->dsp.vector_fmul(chunk + block_size*j, tctx->tmp_buf,
790
                                  block_size);
791

    
792
        }
793

    
794
        if (ftype == FT_LONG) {
795
            float pgain_step = 25000. / ((1 << mtab->pgain_bit) - 1);
796
            int p_coef = get_bits(gb, tctx->mtab->ppc_period_bit);
797
            int g_coef = get_bits(gb, tctx->mtab->pgain_bit);
798
            float v = 1./8192*
799
                mulawinv(pgain_step*g_coef+ pgain_step/2, 25000., PGAIN_MU);
800

    
801
            decode_ppc(tctx, p_coef, ppc_shape + i*mtab->ppc_shape_len, v,
802
                       chunk);
803
        }
804

    
805
        decode_lsp(tctx, lpc_idx1[i], lpc_idx2[i], lpc_hist_idx[i], lsp,
806
                   tctx->lsp_hist[i]);
807

    
808
        dec_lpc_spectrum_inv(tctx, lsp, ftype, tctx->tmp_buf);
809

    
810
        for (j=0; j < mtab->fmode[ftype].sub; j++) {
811
            tctx->dsp.vector_fmul(chunk, tctx->tmp_buf, block_size);
812
            chunk += block_size;
813
        }
814
    }
815
}
816

    
817
static int twin_decode_frame(AVCodecContext * avctx, void *data,
818
                             int *data_size, AVPacket *avpkt)
819
{
820
    const uint8_t *buf = avpkt->data;
821
    int buf_size = avpkt->size;
822
    TwinContext *tctx = avctx->priv_data;
823
    GetBitContext gb;
824
    const ModeTab *mtab = tctx->mtab;
825
    float *out = data;
826
    enum FrameType ftype;
827
    int window_type;
828
    static const enum FrameType wtype_to_ftype_table[] = {
829
        FT_LONG,   FT_LONG, FT_SHORT, FT_LONG,
830
        FT_MEDIUM, FT_LONG, FT_LONG,  FT_MEDIUM, FT_MEDIUM
831
    };
832

    
833
    if (buf_size*8 < avctx->bit_rate*mtab->size/avctx->sample_rate + 8) {
834
        av_log(avctx, AV_LOG_ERROR,
835
               "Frame too small (%d bytes). Truncated file?\n", buf_size);
836
        *data_size = 0;
837
        return buf_size;
838
    }
839

    
840
    init_get_bits(&gb, buf, buf_size * 8);
841
    skip_bits(&gb, get_bits(&gb, 8));
842
    window_type = get_bits(&gb, WINDOW_TYPE_BITS);
843

    
844
    if (window_type > 8) {
845
        av_log(avctx, AV_LOG_ERROR, "Invalid window type, broken sample?\n");
846
        return -1;
847
    }
848

    
849
    ftype = wtype_to_ftype_table[window_type];
850

    
851
    read_and_decode_spectrum(tctx, &gb, tctx->spectrum, ftype);
852

    
853
    imdct_output(tctx, ftype, window_type, out);
854

    
855
    FFSWAP(float*, tctx->curr_frame, tctx->prev_frame);
856

    
857
    if (tctx->avctx->frame_number < 2) {
858
        *data_size=0;
859
        return buf_size;
860
    }
861

    
862
    tctx->dsp.vector_clipf(out, out, -32700./(1<<15), 32700./(1<<15),
863
                           avctx->channels * mtab->size);
864

    
865
    *data_size = mtab->size*avctx->channels*4;
866

    
867
    return buf_size;
868
}
869

    
870
/**
871
 * Init IMDCT and windowing tables
872
 */
873
static av_cold void init_mdct_win(TwinContext *tctx)
874
{
875
    int i,j;
876
    const ModeTab *mtab = tctx->mtab;
877
    int size_s = mtab->size / mtab->fmode[FT_SHORT].sub;
878
    int size_m = mtab->size / mtab->fmode[FT_MEDIUM].sub;
879
    int channels = tctx->avctx->channels;
880
    float norm = channels == 1 ? 2. : 1.;
881

    
882
    for (i=0; i < 3; i++) {
883
        int bsize = tctx->mtab->size/tctx->mtab->fmode[i].sub;
884
        ff_mdct_init(&tctx->mdct_ctx[i], av_log2(bsize) + 1, 1,
885
                     -sqrt(norm/bsize) / (1<<15));
886
    }
887

    
888
    tctx->tmp_buf  = av_malloc(mtab->size            * sizeof(*tctx->tmp_buf));
889

    
890
    tctx->spectrum  = av_malloc(2*mtab->size*channels*sizeof(float));
891
    tctx->curr_frame = av_malloc(2*mtab->size*channels*sizeof(float));
892
    tctx->prev_frame  = av_malloc(2*mtab->size*channels*sizeof(float));
893

    
894
    for(i=0; i < 3; i++) {
895
        int m = 4*mtab->size/mtab->fmode[i].sub;
896
        double freq = 2*M_PI/m;
897
        tctx->cos_tabs[i] = av_malloc((m/4)*sizeof(*tctx->cos_tabs));
898

    
899
        for (j=0; j <= m/8; j++)
900
            tctx->cos_tabs[i][j] = cos((2*j + 1)*freq);
901
        for (j=1; j <  m/8; j++)
902
            tctx->cos_tabs[i][m/4-j] = tctx->cos_tabs[i][j];
903
    }
904

    
905

    
906
    ff_sine_window_init(ff_sine_windows[av_log2(size_m)     - 7], size_m  );
907
    ff_sine_window_init(ff_sine_windows[av_log2(size_s/2)   - 7], size_s/2);
908
    ff_sine_window_init(ff_sine_windows[av_log2(mtab->size) - 7], mtab->size);
909
}
910

    
911
/**
912
 * Interpret the data as if it were a num_blocks x line_len[0] matrix and for
913
 * each line do a cyclic permutation, i.e.
914
 * abcdefghijklm -> defghijklmabc
915
 * where the amount to be shifted is evaluated depending on the column.
916
 */
917
static void permutate_in_line(int16_t *tab, int num_vect, int num_blocks,
918
                              int block_size,
919
                              const uint8_t line_len[2], int length_div,
920
                              enum FrameType ftype)
921

    
922
{
923
    int i,j;
924

    
925
    for (i=0; i < line_len[0]; i++) {
926
        int shift;
927

    
928
        if (num_blocks == 1 ||
929
            (ftype == FT_LONG && num_vect % num_blocks) ||
930
            (ftype != FT_LONG && num_vect & 1         ) ||
931
            i == line_len[1]) {
932
            shift = 0;
933
        } else if (ftype == FT_LONG) {
934
            shift = i;
935
        } else
936
            shift = i*i;
937

    
938
        for (j=0; j < num_vect && (j+num_vect*i < block_size*num_blocks); j++)
939
            tab[i*num_vect+j] = i*num_vect + (j + shift) % num_vect;
940
    }
941
}
942

    
943
/**
944
 * Interpret the input data as in the following table:
945
 *
946
 * \verbatim
947
 *
948
 * abcdefgh
949
 * ijklmnop
950
 * qrstuvw
951
 * x123456
952
 *
953
 * \endverbatim
954
 *
955
 * and transpose it, giving the output
956
 * aiqxbjr1cks2dlt3emu4fvn5gow6hp
957
 */
958
static void transpose_perm(int16_t *out, int16_t *in, int num_vect,
959
                           const uint8_t line_len[2], int length_div)
960
{
961
    int i,j;
962
    int cont= 0;
963
    for (i=0; i < num_vect; i++)
964
        for (j=0; j < line_len[i >= length_div]; j++)
965
            out[cont++] = in[j*num_vect + i];
966
}
967

    
968
static void linear_perm(int16_t *out, int16_t *in, int n_blocks, int size)
969
{
970
    int block_size = size/n_blocks;
971
    int i;
972

    
973
    for (i=0; i < size; i++)
974
        out[i] = block_size * (in[i] % n_blocks) + in[i] / n_blocks;
975
}
976

    
977
static av_cold void construct_perm_table(TwinContext *tctx,enum FrameType ftype)
978
{
979
    int block_size;
980
    const ModeTab *mtab = tctx->mtab;
981
    int size = tctx->avctx->channels*mtab->fmode[ftype].sub;
982
    int16_t *tmp_perm = (int16_t *) tctx->tmp_buf;
983

    
984
    if (ftype == FT_PPC) {
985
        size  = tctx->avctx->channels;
986
        block_size = mtab->ppc_shape_len;
987
    } else
988
        block_size = mtab->size / mtab->fmode[ftype].sub;
989

    
990
    permutate_in_line(tmp_perm, tctx->n_div[ftype], size,
991
                      block_size, tctx->length[ftype],
992
                      tctx->length_change[ftype], ftype);
993

    
994
    transpose_perm(tctx->permut[ftype], tmp_perm, tctx->n_div[ftype],
995
                   tctx->length[ftype], tctx->length_change[ftype]);
996

    
997
    linear_perm(tctx->permut[ftype], tctx->permut[ftype], size,
998
                size*block_size);
999
}
1000

    
1001
static av_cold void init_bitstream_params(TwinContext *tctx)
1002
{
1003
    const ModeTab *mtab = tctx->mtab;
1004
    int n_ch = tctx->avctx->channels;
1005
    int total_fr_bits = tctx->avctx->bit_rate*mtab->size/
1006
                             tctx->avctx->sample_rate;
1007

    
1008
    int lsp_bits_per_block = n_ch*(mtab->lsp_bit0 + mtab->lsp_bit1 +
1009
                                   mtab->lsp_split*mtab->lsp_bit2);
1010

    
1011
    int ppc_bits = n_ch*(mtab->pgain_bit + mtab->ppc_shape_bit +
1012
                         mtab->ppc_period_bit);
1013

    
1014
    int bsize_no_main_cb[3];
1015
    int bse_bits[3];
1016
    int i;
1017

    
1018
    for (i=0; i < 3; i++)
1019
        // +1 for history usage switch
1020
        bse_bits[i] = n_ch *
1021
            (mtab->fmode[i].bark_n_coef * mtab->fmode[i].bark_n_bit + 1);
1022

    
1023
    bsize_no_main_cb[2] = bse_bits[2] + lsp_bits_per_block + ppc_bits +
1024
                          WINDOW_TYPE_BITS + n_ch*GAIN_BITS;
1025

    
1026
    for (i=0; i < 2; i++)
1027
        bsize_no_main_cb[i] =
1028
            lsp_bits_per_block + n_ch*GAIN_BITS + WINDOW_TYPE_BITS +
1029
            mtab->fmode[i].sub*(bse_bits[i] + n_ch*SUB_GAIN_BITS);
1030

    
1031
    // The remaining bits are all used for the main spectrum coefficients
1032
    for (i=0; i < 4; i++) {
1033
        int bit_size;
1034
        int vect_size;
1035
        int rounded_up, rounded_down, num_rounded_down, num_rounded_up;
1036
        if (i == 3) {
1037
            bit_size  = n_ch * mtab->ppc_shape_bit;
1038
            vect_size = n_ch * mtab->ppc_shape_len;
1039
        } else {
1040
            bit_size = total_fr_bits - bsize_no_main_cb[i];
1041
            vect_size = n_ch * mtab->size;
1042
        }
1043

    
1044
        tctx->n_div[i] = (bit_size + 13) / 14;
1045

    
1046
        rounded_up   = (bit_size + tctx->n_div[i] - 1)/tctx->n_div[i];
1047
        rounded_down = (bit_size           )/tctx->n_div[i];
1048
        num_rounded_down = rounded_up * tctx->n_div[i] - bit_size;
1049
        num_rounded_up = tctx->n_div[i] - num_rounded_down;
1050
        tctx->bits_main_spec[0][i][0] = (rounded_up   + 1)/2;
1051
        tctx->bits_main_spec[1][i][0] = (rounded_up      )/2;
1052
        tctx->bits_main_spec[0][i][1] = (rounded_down + 1)/2;
1053
        tctx->bits_main_spec[1][i][1] = (rounded_down    )/2;
1054
        tctx->bits_main_spec_change[i] = num_rounded_up;
1055

    
1056
        rounded_up   = (vect_size + tctx->n_div[i] - 1)/tctx->n_div[i];
1057
        rounded_down = (vect_size                     )/tctx->n_div[i];
1058
        num_rounded_down = rounded_up * tctx->n_div[i] - vect_size;
1059
        num_rounded_up = tctx->n_div[i] - num_rounded_down;
1060
        tctx->length[i][0] = rounded_up;
1061
        tctx->length[i][1] = rounded_down;
1062
        tctx->length_change[i] = num_rounded_up;
1063
    }
1064

    
1065
    for (i=0; i < 4; i++)
1066
        construct_perm_table(tctx, i);
1067
}
1068

    
1069
static av_cold int twin_decode_init(AVCodecContext *avctx)
1070
{
1071
    TwinContext *tctx = avctx->priv_data;
1072
    int isampf = avctx->sample_rate/1000;
1073
    int ibps = avctx->bit_rate/(1000 * avctx->channels);
1074

    
1075
    tctx->avctx       = avctx;
1076
    avctx->sample_fmt = SAMPLE_FMT_FLT;
1077

    
1078
    if (avctx->channels > 2) {
1079
        av_log(avctx, AV_LOG_ERROR, "Unsupported number of channels: %i\n",
1080
               avctx->channels);
1081
        return -1;
1082
    }
1083

    
1084
    switch ((isampf << 8) +  ibps) {
1085
    case (8 <<8) +  8: tctx->mtab = &mode_08_08; break;
1086
    case (11<<8) +  8: tctx->mtab = &mode_11_08; break;
1087
    case (11<<8) + 10: tctx->mtab = &mode_11_10; break;
1088
    case (16<<8) + 16: tctx->mtab = &mode_16_16; break;
1089
    case (22<<8) + 20: tctx->mtab = &mode_22_20; break;
1090
    case (22<<8) + 24: tctx->mtab = &mode_22_24; break;
1091
    case (22<<8) + 32: tctx->mtab = &mode_22_32; break;
1092
    case (44<<8) + 40: tctx->mtab = &mode_44_40; break;
1093
    case (44<<8) + 48: tctx->mtab = &mode_44_48; break;
1094
    default:
1095
        av_log(avctx, AV_LOG_ERROR, "This version does not support %d kHz - %d kbit/s/ch mode.\n", isampf, isampf);
1096
        return -1;
1097
    }
1098

    
1099
    dsputil_init(&tctx->dsp, avctx);
1100
    init_mdct_win(tctx);
1101
    init_bitstream_params(tctx);
1102

    
1103
    memset_float(tctx->bark_hist[0][0], 0.1, FF_ARRAY_ELEMS(tctx->bark_hist));
1104

    
1105
    return 0;
1106
}
1107

    
1108
static av_cold int twin_decode_close(AVCodecContext *avctx)
1109
{
1110
    TwinContext *tctx = avctx->priv_data;
1111
    int i;
1112

    
1113
    for (i=0; i < 3; i++) {
1114
        ff_mdct_end(&tctx->mdct_ctx[i]);
1115
        av_free(tctx->cos_tabs[i]);
1116
    }
1117

    
1118

    
1119
    av_free(tctx->curr_frame);
1120
    av_free(tctx->spectrum);
1121
    av_free(tctx->prev_frame);
1122
    av_free(tctx->tmp_buf);
1123

    
1124
    return 0;
1125
}
1126

    
1127
AVCodec twinvq_decoder =
1128
{
1129
    "twinvq",
1130
    CODEC_TYPE_AUDIO,
1131
    CODEC_ID_TWINVQ,
1132
    sizeof(TwinContext),
1133
    twin_decode_init,
1134
    NULL,
1135
    twin_decode_close,
1136
    twin_decode_frame,
1137
    .long_name = NULL_IF_CONFIG_SMALL("VQF TwinVQ"),
1138
};