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1
/*
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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 Libav.
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 *
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 * Libav 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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 * Libav 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 Libav; 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 "fft.h"
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#include "lsp.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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/**
41
 * 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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    FFTContext mdct_ctx[3];
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179
    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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193
    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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198
    float *cos_tabs[3];
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200
    // scratch buffers
201
    float *tmp_buf;
202
} TwinContext;
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204
#define PPC_SHAPE_CB_SIZE 64
205
#define PPC_SHAPE_LEN_MAX 60
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#define SUB_AMP_MAX       4500.0
207
#define MULAW_MU          100.0
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#define GAIN_BITS         8
209
#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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#define LSP_COEFS_MAX     20
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#define LSP_SPLIT_MAX     4
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#define CHANNELS_MAX      2
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#define SUBBLOCKS_MAX     16
217
#define BARK_N_COEF_MAX   4
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219
/** @note not speed critical, hence not optimized */
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static void memset_float(float *buf, float val, int size)
221
{
222
    while (size--)
223
        *buf++ = val;
224
}
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226
/**
227
 * Evaluate a single LPC amplitude spectrum envelope coefficient from the line
228
 * spectrum pairs.
229
 *
230
 * @param lsp a vector of the cosinus of the LSP values
231
 * @param cos_val cos(PI*i/N) where i is the index of the LPC amplitude
232
 * @param order the order of the LSP (and the size of the *lsp buffer). Must
233
 *        be a multiple of four.
234
 * @return the LPC value
235
 *
236
 * @todo reuse code from vorbis_dec.c: vorbis_floor0_decode
237
 */
238
static float eval_lpc_spectrum(const float *lsp, float cos_val, int order)
239
{
240
    int j;
241
    float p = 0.5f;
242
    float q = 0.5f;
243
    float two_cos_w = 2.0f*cos_val;
244

    
245
    for (j = 0; j + 1 < order; j += 2*2) {
246
        // Unroll the loop once since order is a multiple of four
247
        q *= lsp[j  ] - two_cos_w;
248
        p *= lsp[j+1] - two_cos_w;
249

    
250
        q *= lsp[j+2] - two_cos_w;
251
        p *= lsp[j+3] - two_cos_w;
252
    }
253

    
254
    p *= p * (2.0f - two_cos_w);
255
    q *= q * (2.0f + two_cos_w);
256

    
257
    return 0.5 / (p + q);
258
}
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260
/**
261
 * Evaluate the LPC amplitude spectrum envelope from the line spectrum pairs.
262
 */
263
static void eval_lpcenv(TwinContext *tctx, const float *cos_vals, float *lpc)
264
{
265
    int i;
266
    const ModeTab *mtab = tctx->mtab;
267
    int size_s = mtab->size / mtab->fmode[FT_SHORT].sub;
268

    
269
    for (i = 0; i < size_s/2; i++) {
270
        float cos_i = tctx->cos_tabs[0][i];
271
        lpc[i]          = eval_lpc_spectrum(cos_vals,  cos_i, mtab->n_lsp);
272
        lpc[size_s-i-1] = eval_lpc_spectrum(cos_vals, -cos_i, mtab->n_lsp);
273
    }
274
}
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276
static void interpolate(float *out, float v1, float v2, int size)
277
{
278
    int i;
279
    float step = (v1 - v2)/(size + 1);
280

    
281
    for (i = 0; i < size; i++) {
282
        v2 += step;
283
        out[i] = v2;
284
    }
285
}
286

    
287
static inline float get_cos(int idx, int part, const float *cos_tab, int size)
288
{
289
    return part ? -cos_tab[size - idx - 1] :
290
                   cos_tab[       idx    ];
291
}
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293
/**
294
 * Evaluate the LPC amplitude spectrum envelope from the line spectrum pairs.
295
 * Probably for speed reasons, the coefficients are evaluated as
296
 * siiiibiiiisiiiibiiiisiiiibiiiisiiiibiiiis ...
297
 * where s is an evaluated value, i is a value interpolated from the others
298
 * and b might be either calculated or interpolated, depending on an
299
 * unexplained condition.
300
 *
301
 * @param step the size of a block "siiiibiiii"
302
 * @param in the cosinus of the LSP data
303
 * @param part is 0 for 0...PI (positive cossinus values) and 1 for PI...2PI
304
          (negative cossinus values)
305
 * @param size the size of the whole output
306
 */
307
static inline void eval_lpcenv_or_interp(TwinContext *tctx,
308
                                         enum FrameType ftype,
309
                                         float *out, const float *in,
310
                                         int size, int step, int part)
311
{
312
    int i;
313
    const ModeTab *mtab = tctx->mtab;
314
    const float *cos_tab = tctx->cos_tabs[ftype];
315

    
316
    // Fill the 's'
317
    for (i = 0; i < size; i += step)
318
        out[i] =
319
            eval_lpc_spectrum(in,
320
                              get_cos(i, part, cos_tab, size),
321
                              mtab->n_lsp);
322

    
323
    // Fill the 'iiiibiiii'
324
    for (i = step; i <= size - 2*step; i += step) {
325
        if (out[i + step] + out[i - step] >  1.95*out[i] ||
326
            out[i + step]                 >=  out[i - step]) {
327
            interpolate(out + i - step + 1, out[i], out[i-step], step - 1);
328
        } else {
329
            out[i - step/2] =
330
                eval_lpc_spectrum(in,
331
                                  get_cos(i-step/2, part, cos_tab, size),
332
                                  mtab->n_lsp);
333
            interpolate(out + i - step   + 1, out[i-step/2], out[i-step  ], step/2 - 1);
334
            interpolate(out + i - step/2 + 1, out[i       ], out[i-step/2], step/2 - 1);
335
        }
336
    }
337

    
338
    interpolate(out + size - 2*step + 1, out[size-step], out[size - 2*step], step - 1);
339
}
340

    
341
static void eval_lpcenv_2parts(TwinContext *tctx, enum FrameType ftype,
342
                               const float *buf, float *lpc,
343
                               int size, int step)
344
{
345
    eval_lpcenv_or_interp(tctx, ftype, lpc         , buf, size/2,   step, 0);
346
    eval_lpcenv_or_interp(tctx, ftype, lpc + size/2, buf, size/2, 2*step, 1);
347

    
348
    interpolate(lpc+size/2-step+1, lpc[size/2], lpc[size/2-step], step);
349

    
350
    memset_float(lpc + size - 2*step + 1, lpc[size - 2*step], 2*step - 1);
351
}
352

    
353
/**
354
 * Inverse quantization. Read CB coefficients for cb1 and cb2 from the
355
 * bitstream, sum the corresponding vectors and write the result to *out
356
 * after permutation.
357
 */
358
static void dequant(TwinContext *tctx, GetBitContext *gb, float *out,
359
                    enum FrameType ftype,
360
                    const int16_t *cb0, const int16_t *cb1, int cb_len)
361
{
362
    int pos = 0;
363
    int i, j;
364

    
365
    for (i = 0; i < tctx->n_div[ftype]; i++) {
366
        int tmp0, tmp1;
367
        int sign0 = 1;
368
        int sign1 = 1;
369
        const int16_t *tab0, *tab1;
370
        int length = tctx->length[ftype][i >= tctx->length_change[ftype]];
371
        int bitstream_second_part = (i >= tctx->bits_main_spec_change[ftype]);
372

    
373
        int bits = tctx->bits_main_spec[0][ftype][bitstream_second_part];
374
        if (bits == 7) {
375
            if (get_bits1(gb))
376
                sign0 = -1;
377
            bits = 6;
378
        }
379
        tmp0 = get_bits(gb, bits);
380

    
381
        bits = tctx->bits_main_spec[1][ftype][bitstream_second_part];
382

    
383
        if (bits == 7) {
384
            if (get_bits1(gb))
385
                sign1 = -1;
386

    
387
            bits = 6;
388
        }
389
        tmp1 = get_bits(gb, bits);
390

    
391
        tab0 = cb0 + tmp0*cb_len;
392
        tab1 = cb1 + tmp1*cb_len;
393

    
394
        for (j = 0; j < length; j++)
395
            out[tctx->permut[ftype][pos+j]] = sign0*tab0[j] + sign1*tab1[j];
396

    
397
        pos += length;
398
    }
399

    
400
}
401

    
402
static inline float mulawinv(float y, float clip, float mu)
403
{
404
    y = av_clipf(y/clip, -1, 1);
405
    return clip * FFSIGN(y) * (exp(log(1+mu) * fabs(y)) - 1) / mu;
406
}
407

    
408
/**
409
 * Evaluate a*b/400 rounded to the nearest integer. When, for example,
410
 * a*b == 200 and the nearest integer is ill-defined, use a table to emulate
411
 * the following broken float-based implementation used by the binary decoder:
412
 *
413
 * \code
414
 * static int very_broken_op(int a, int b)
415
 * {
416
 *    static float test; // Ugh, force gcc to do the division first...
417
 *
418
 *    test = a/400.;
419
 *    return b * test +  0.5;
420
 * }
421
 * \endcode
422
 *
423
 * @note if this function is replaced by just ROUNDED_DIV(a*b,400.), the stddev
424
 * between the original file (before encoding with Yamaha encoder) and the
425
 * decoded output increases, which leads one to believe that the encoder expects
426
 * exactly this broken calculation.
427
 */
428
static int very_broken_op(int a, int b)
429
{
430
    int x = a*b + 200;
431
    int size;
432
    const uint8_t *rtab;
433

    
434
    if (x%400 || b%5)
435
        return x/400;
436

    
437
    x /= 400;
438

    
439
    size = tabs[b/5].size;
440
    rtab = tabs[b/5].tab;
441
    return x - rtab[size*av_log2(2*(x - 1)/size)+(x - 1)%size];
442
}
443

    
444
/**
445
 * Sum to data a periodic peak of a given period, width and shape.
446
 *
447
 * @param period the period of the peak divised by 400.0
448
 */
449
static void add_peak(int period, int width, const float *shape,
450
                     float ppc_gain, float *speech, int len)
451
{
452
    int i, j;
453

    
454
    const float *shape_end = shape + len;
455
    int center;
456

    
457
    // First peak centered around zero
458
    for (i = 0; i < width/2; i++)
459
        speech[i] += ppc_gain * *shape++;
460

    
461
    for (i = 1; i < ROUNDED_DIV(len,width) ; i++) {
462
        center = very_broken_op(period, i);
463
        for (j = -width/2; j < (width+1)/2; j++)
464
            speech[j+center] += ppc_gain * *shape++;
465
    }
466

    
467
    // For the last block, be careful not to go beyond the end of the buffer
468
    center = very_broken_op(period, i);
469
    for (j = -width/2; j < (width + 1)/2 && shape < shape_end; j++)
470
        speech[j+center] += ppc_gain * *shape++;
471
}
472

    
473
static void decode_ppc(TwinContext *tctx, int period_coef, const float *shape,
474
                       float ppc_gain, float *speech)
475
{
476
    const ModeTab *mtab = tctx->mtab;
477
    int isampf = tctx->avctx->sample_rate/1000;
478
    int ibps = tctx->avctx->bit_rate/(1000 * tctx->avctx->channels);
479
    int min_period = ROUNDED_DIV(  40*2*mtab->size, isampf);
480
    int max_period = ROUNDED_DIV(6*40*2*mtab->size, isampf);
481
    int period_range = max_period - min_period;
482

    
483
    // This is actually the period multiplied by 400. It is just linearly coded
484
    // between its maximum and minimum value.
485
    int period = min_period +
486
        ROUNDED_DIV(period_coef*period_range, (1 << mtab->ppc_period_bit) - 1);
487
    int width;
488

    
489
    if (isampf == 22 && ibps == 32) {
490
        // For some unknown reason, NTT decided to code this case differently...
491
        width = ROUNDED_DIV((period + 800)* mtab->peak_per2wid, 400*mtab->size);
492
    } else
493
        width =             (period      )* mtab->peak_per2wid/(400*mtab->size);
494

    
495
    add_peak(period, width, shape, ppc_gain, speech, mtab->ppc_shape_len);
496
}
497

    
498
static void dec_gain(TwinContext *tctx, GetBitContext *gb, enum FrameType ftype,
499
                     float *out)
500
{
501
    const ModeTab *mtab = tctx->mtab;
502
    int i, j;
503
    int sub = mtab->fmode[ftype].sub;
504
    float step     = AMP_MAX     / ((1 <<     GAIN_BITS) - 1);
505
    float sub_step = SUB_AMP_MAX / ((1 << SUB_GAIN_BITS) - 1);
506

    
507
    if (ftype == FT_LONG) {
508
        for (i = 0; i < tctx->avctx->channels; i++)
509
            out[i] = (1./(1<<13)) *
510
                mulawinv(step * 0.5 + step * get_bits(gb, GAIN_BITS),
511
                         AMP_MAX, MULAW_MU);
512
    } else {
513
        for (i = 0; i < tctx->avctx->channels; i++) {
514
            float val = (1./(1<<23)) *
515
                mulawinv(step * 0.5 + step * get_bits(gb, GAIN_BITS),
516
                         AMP_MAX, MULAW_MU);
517

    
518
            for (j = 0; j < sub; j++) {
519
                out[i*sub + j] =
520
                    val*mulawinv(sub_step* 0.5 +
521
                                 sub_step* get_bits(gb, SUB_GAIN_BITS),
522
                                 SUB_AMP_MAX, MULAW_MU);
523
            }
524
        }
525
    }
526
}
527

    
528
/**
529
 * Rearrange the LSP coefficients so that they have a minimum distance of
530
 * min_dist. This function does it exactly as described in section of 3.2.4
531
 * of the G.729 specification (but interestingly is different from what the
532
 * reference decoder actually does).
533
 */
534
static void rearrange_lsp(int order, float *lsp, float min_dist)
535
{
536
    int i;
537
    float min_dist2 = min_dist * 0.5;
538
    for (i = 1; i < order; i++)
539
        if (lsp[i] - lsp[i-1] < min_dist) {
540
            float avg = (lsp[i] + lsp[i-1]) * 0.5;
541

    
542
            lsp[i-1] = avg - min_dist2;
543
            lsp[i  ] = avg + min_dist2;
544
        }
545
}
546

    
547
static void decode_lsp(TwinContext *tctx, int lpc_idx1, uint8_t *lpc_idx2,
548
                       int lpc_hist_idx, float *lsp, float *hist)
549
{
550
    const ModeTab *mtab = tctx->mtab;
551
    int i, j;
552

    
553
    const float *cb  =  mtab->lspcodebook;
554
    const float *cb2 =  cb  + (1 << mtab->lsp_bit1)*mtab->n_lsp;
555
    const float *cb3 =  cb2 + (1 << mtab->lsp_bit2)*mtab->n_lsp;
556

    
557
    const int8_t funny_rounding[4] = {
558
        -2,
559
        mtab->lsp_split == 4 ? -2 : 1,
560
        mtab->lsp_split == 4 ? -2 : 1,
561
        0
562
    };
563

    
564
    j = 0;
565
    for (i = 0; i < mtab->lsp_split; i++) {
566
        int chunk_end = ((i + 1)*mtab->n_lsp + funny_rounding[i])/mtab->lsp_split;
567
        for (; j < chunk_end; j++)
568
            lsp[j] = cb [lpc_idx1    * mtab->n_lsp + j] +
569
                     cb2[lpc_idx2[i] * mtab->n_lsp + j];
570
    }
571

    
572
    rearrange_lsp(mtab->n_lsp, lsp, 0.0001);
573

    
574
    for (i = 0; i < mtab->n_lsp; i++) {
575
        float tmp1 = 1. -          cb3[lpc_hist_idx*mtab->n_lsp + i];
576
        float tmp2 =     hist[i] * cb3[lpc_hist_idx*mtab->n_lsp + i];
577
        hist[i] = lsp[i];
578
        lsp[i]  = lsp[i] * tmp1 + tmp2;
579
    }
580

    
581
    rearrange_lsp(mtab->n_lsp, lsp, 0.0001);
582
    rearrange_lsp(mtab->n_lsp, lsp, 0.000095);
583
    ff_sort_nearly_sorted_floats(lsp, mtab->n_lsp);
584
}
585

    
586
static void dec_lpc_spectrum_inv(TwinContext *tctx, float *lsp,
587
                                 enum FrameType ftype, float *lpc)
588
{
589
    int i;
590
    int size = tctx->mtab->size / tctx->mtab->fmode[ftype].sub;
591

    
592
    for (i = 0; i < tctx->mtab->n_lsp; i++)
593
        lsp[i] =  2*cos(lsp[i]);
594

    
595
    switch (ftype) {
596
    case FT_LONG:
597
        eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 8);
598
        break;
599
    case FT_MEDIUM:
600
        eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 2);
601
        break;
602
    case FT_SHORT:
603
        eval_lpcenv(tctx, lsp, lpc);
604
        break;
605
    }
606
}
607

    
608
static void imdct_and_window(TwinContext *tctx, enum FrameType ftype, int wtype,
609
                            float *in, float *prev, int ch)
610
{
611
    FFTContext *mdct = &tctx->mdct_ctx[ftype];
612
    const ModeTab *mtab = tctx->mtab;
613
    int bsize = mtab->size / mtab->fmode[ftype].sub;
614
    int size  = mtab->size;
615
    float *buf1 = tctx->tmp_buf;
616
    int j;
617
    int wsize; // Window size
618
    float *out = tctx->curr_frame + 2*ch*mtab->size;
619
    float *out2 = out;
620
    float *prev_buf;
621
    int first_wsize;
622

    
623
    static const uint8_t wtype_to_wsize[]      = {0, 0, 2, 2, 2, 1, 0, 1, 1};
624
    int types_sizes[] = {
625
        mtab->size /    mtab->fmode[FT_LONG  ].sub,
626
        mtab->size /    mtab->fmode[FT_MEDIUM].sub,
627
        mtab->size / (2*mtab->fmode[FT_SHORT ].sub),
628
    };
629

    
630
    wsize = types_sizes[wtype_to_wsize[wtype]];
631
    first_wsize = wsize;
632
    prev_buf = prev + (size - bsize)/2;
633

    
634
    for (j = 0; j < mtab->fmode[ftype].sub; j++) {
635
        int sub_wtype = ftype == FT_MEDIUM ? 8 : wtype;
636

    
637
        if (!j && wtype == 4)
638
            sub_wtype = 4;
639
        else if (j == mtab->fmode[ftype].sub-1 && wtype == 7)
640
            sub_wtype = 7;
641

    
642
        wsize = types_sizes[wtype_to_wsize[sub_wtype]];
643

    
644
        mdct->imdct_half(mdct, buf1 + bsize*j, in + bsize*j);
645

    
646
        tctx->dsp.vector_fmul_window(out2,
647
                                     prev_buf + (bsize-wsize)/2,
648
                                     buf1 + bsize*j,
649
                                     ff_sine_windows[av_log2(wsize)],
650
                                     wsize/2);
651
        out2 += wsize;
652

    
653
        memcpy(out2, buf1 + bsize*j + wsize/2, (bsize - wsize/2)*sizeof(float));
654

    
655
        out2 += ftype == FT_MEDIUM ? (bsize-wsize)/2 : bsize - wsize;
656

    
657
        prev_buf = buf1 + bsize*j + bsize/2;
658
    }
659

    
660
    tctx->last_block_pos[ch] = (size + first_wsize)/2;
661
}
662

    
663
static void imdct_output(TwinContext *tctx, enum FrameType ftype, int wtype,
664
                         float *out)
665
{
666
    const ModeTab *mtab = tctx->mtab;
667
    float *prev_buf = tctx->prev_frame + tctx->last_block_pos[0];
668
    int i, j;
669

    
670
    for (i = 0; i < tctx->avctx->channels; i++) {
671
        imdct_and_window(tctx, ftype, wtype,
672
                         tctx->spectrum + i*mtab->size,
673
                         prev_buf + 2*i*mtab->size,
674
                         i);
675
    }
676

    
677
    if (tctx->avctx->channels == 2) {
678
        for (i = 0; i < mtab->size - tctx->last_block_pos[0]; i++) {
679
            float f1 = prev_buf[               i];
680
            float f2 = prev_buf[2*mtab->size + i];
681
            out[2*i    ] = f1 + f2;
682
            out[2*i + 1] = f1 - f2;
683
        }
684
        for (j = 0; i < mtab->size; j++,i++) {
685
            float f1 = tctx->curr_frame[               j];
686
            float f2 = tctx->curr_frame[2*mtab->size + j];
687
            out[2*i    ] = f1 + f2;
688
            out[2*i + 1] = f1 - f2;
689
        }
690
    } else {
691
        memcpy(out, prev_buf,
692
               (mtab->size - tctx->last_block_pos[0]) * sizeof(*out));
693

    
694
        out +=  mtab->size - tctx->last_block_pos[0];
695

    
696
        memcpy(out, tctx->curr_frame,
697
               (tctx->last_block_pos[0]) * sizeof(*out));
698
    }
699

    
700
}
701

    
702
static void dec_bark_env(TwinContext *tctx, const uint8_t *in, int use_hist,
703
                         int ch, float *out, float gain, enum FrameType ftype)
704
{
705
    const ModeTab *mtab = tctx->mtab;
706
    int i,j;
707
    float *hist = tctx->bark_hist[ftype][ch];
708
    float val = ((const float []) {0.4, 0.35, 0.28})[ftype];
709
    int bark_n_coef  = mtab->fmode[ftype].bark_n_coef;
710
    int fw_cb_len = mtab->fmode[ftype].bark_env_size / bark_n_coef;
711
    int idx = 0;
712

    
713
    for (i = 0; i < fw_cb_len; i++)
714
        for (j = 0; j < bark_n_coef; j++, idx++) {
715
            float tmp2 =
716
                mtab->fmode[ftype].bark_cb[fw_cb_len*in[j] + i] * (1./4096);
717
            float st = use_hist ?
718
                (1. - val) * tmp2 + val*hist[idx] + 1. : tmp2 + 1.;
719

    
720
            hist[idx] = tmp2;
721
            if (st < -1.) st = 1.;
722

    
723
            memset_float(out, st * gain, mtab->fmode[ftype].bark_tab[idx]);
724
            out += mtab->fmode[ftype].bark_tab[idx];
725
        }
726

    
727
}
728

    
729
static void read_and_decode_spectrum(TwinContext *tctx, GetBitContext *gb,
730
                                     float *out, enum FrameType ftype)
731
{
732
    const ModeTab *mtab = tctx->mtab;
733
    int channels = tctx->avctx->channels;
734
    int sub = mtab->fmode[ftype].sub;
735
    int block_size = mtab->size / sub;
736
    float gain[CHANNELS_MAX*SUBBLOCKS_MAX];
737
    float ppc_shape[PPC_SHAPE_LEN_MAX * CHANNELS_MAX * 4];
738
    uint8_t bark1[CHANNELS_MAX][SUBBLOCKS_MAX][BARK_N_COEF_MAX];
739
    uint8_t bark_use_hist[CHANNELS_MAX][SUBBLOCKS_MAX];
740

    
741
    uint8_t lpc_idx1[CHANNELS_MAX];
742
    uint8_t lpc_idx2[CHANNELS_MAX][LSP_SPLIT_MAX];
743
    uint8_t lpc_hist_idx[CHANNELS_MAX];
744

    
745
    int i, j, k;
746

    
747
    dequant(tctx, gb, out, ftype,
748
            mtab->fmode[ftype].cb0, mtab->fmode[ftype].cb1,
749
            mtab->fmode[ftype].cb_len_read);
750

    
751
    for (i = 0; i < channels; i++)
752
        for (j = 0; j < sub; j++)
753
            for (k = 0; k < mtab->fmode[ftype].bark_n_coef; k++)
754
                bark1[i][j][k] =
755
                    get_bits(gb, mtab->fmode[ftype].bark_n_bit);
756

    
757
    for (i = 0; i < channels; i++)
758
        for (j = 0; j < sub; j++)
759
            bark_use_hist[i][j] = get_bits1(gb);
760

    
761
    dec_gain(tctx, gb, ftype, gain);
762

    
763
    for (i = 0; i < channels; i++) {
764
        lpc_hist_idx[i] = get_bits(gb, tctx->mtab->lsp_bit0);
765
        lpc_idx1    [i] = get_bits(gb, tctx->mtab->lsp_bit1);
766

    
767
        for (j = 0; j < tctx->mtab->lsp_split; j++)
768
            lpc_idx2[i][j] = get_bits(gb, tctx->mtab->lsp_bit2);
769
    }
770

    
771
    if (ftype == FT_LONG) {
772
        int cb_len_p = (tctx->n_div[3] + mtab->ppc_shape_len*channels - 1)/
773
            tctx->n_div[3];
774
        dequant(tctx, gb, ppc_shape, FT_PPC, mtab->ppc_shape_cb,
775
                mtab->ppc_shape_cb + cb_len_p*PPC_SHAPE_CB_SIZE, cb_len_p);
776
    }
777

    
778
    for (i = 0; i < channels; i++) {
779
        float *chunk = out + mtab->size * i;
780
        float lsp[LSP_COEFS_MAX];
781

    
782
        for (j = 0; j < sub; j++) {
783
            dec_bark_env(tctx, bark1[i][j], bark_use_hist[i][j], i,
784
                         tctx->tmp_buf, gain[sub*i+j], ftype);
785

    
786
            tctx->dsp.vector_fmul(chunk + block_size*j, chunk + block_size*j, tctx->tmp_buf,
787
                                  block_size);
788

    
789
        }
790

    
791
        if (ftype == FT_LONG) {
792
            float pgain_step = 25000. / ((1 << mtab->pgain_bit) - 1);
793
            int p_coef = get_bits(gb, tctx->mtab->ppc_period_bit);
794
            int g_coef = get_bits(gb, tctx->mtab->pgain_bit);
795
            float v = 1./8192*
796
                mulawinv(pgain_step*g_coef+ pgain_step/2, 25000., PGAIN_MU);
797

    
798
            decode_ppc(tctx, p_coef, ppc_shape + i*mtab->ppc_shape_len, v,
799
                       chunk);
800
        }
801

    
802
        decode_lsp(tctx, lpc_idx1[i], lpc_idx2[i], lpc_hist_idx[i], lsp,
803
                   tctx->lsp_hist[i]);
804

    
805
        dec_lpc_spectrum_inv(tctx, lsp, ftype, tctx->tmp_buf);
806

    
807
        for (j = 0; j < mtab->fmode[ftype].sub; j++) {
808
            tctx->dsp.vector_fmul(chunk, chunk, tctx->tmp_buf, block_size);
809
            chunk += block_size;
810
        }
811
    }
812
}
813

    
814
static int twin_decode_frame(AVCodecContext * avctx, void *data,
815
                             int *data_size, AVPacket *avpkt)
816
{
817
    const uint8_t *buf = avpkt->data;
818
    int buf_size = avpkt->size;
819
    TwinContext *tctx = avctx->priv_data;
820
    GetBitContext gb;
821
    const ModeTab *mtab = tctx->mtab;
822
    float *out = data;
823
    enum FrameType ftype;
824
    int window_type;
825
    static const enum FrameType wtype_to_ftype_table[] = {
826
        FT_LONG,   FT_LONG, FT_SHORT, FT_LONG,
827
        FT_MEDIUM, FT_LONG, FT_LONG,  FT_MEDIUM, FT_MEDIUM
828
    };
829

    
830
    if (buf_size*8 < avctx->bit_rate*mtab->size/avctx->sample_rate + 8) {
831
        av_log(avctx, AV_LOG_ERROR,
832
               "Frame too small (%d bytes). Truncated file?\n", buf_size);
833
        *data_size = 0;
834
        return buf_size;
835
    }
836

    
837
    init_get_bits(&gb, buf, buf_size * 8);
838
    skip_bits(&gb, get_bits(&gb, 8));
839
    window_type = get_bits(&gb, WINDOW_TYPE_BITS);
840

    
841
    if (window_type > 8) {
842
        av_log(avctx, AV_LOG_ERROR, "Invalid window type, broken sample?\n");
843
        return -1;
844
    }
845

    
846
    ftype = wtype_to_ftype_table[window_type];
847

    
848
    read_and_decode_spectrum(tctx, &gb, tctx->spectrum, ftype);
849

    
850
    imdct_output(tctx, ftype, window_type, out);
851

    
852
    FFSWAP(float*, tctx->curr_frame, tctx->prev_frame);
853

    
854
    if (tctx->avctx->frame_number < 2) {
855
        *data_size=0;
856
        return buf_size;
857
    }
858

    
859
    *data_size = mtab->size*avctx->channels*4;
860

    
861
    return buf_size;
862
}
863

    
864
/**
865
 * Init IMDCT and windowing tables
866
 */
867
static av_cold void init_mdct_win(TwinContext *tctx)
868
{
869
    int i,j;
870
    const ModeTab *mtab = tctx->mtab;
871
    int size_s = mtab->size / mtab->fmode[FT_SHORT].sub;
872
    int size_m = mtab->size / mtab->fmode[FT_MEDIUM].sub;
873
    int channels = tctx->avctx->channels;
874
    float norm = channels == 1 ? 2. : 1.;
875

    
876
    for (i = 0; i < 3; i++) {
877
        int bsize = tctx->mtab->size/tctx->mtab->fmode[i].sub;
878
        ff_mdct_init(&tctx->mdct_ctx[i], av_log2(bsize) + 1, 1,
879
                     -sqrt(norm/bsize) / (1<<15));
880
    }
881

    
882
    tctx->tmp_buf  = av_malloc(mtab->size            * sizeof(*tctx->tmp_buf));
883

    
884
    tctx->spectrum  = av_malloc(2*mtab->size*channels*sizeof(float));
885
    tctx->curr_frame = av_malloc(2*mtab->size*channels*sizeof(float));
886
    tctx->prev_frame  = av_malloc(2*mtab->size*channels*sizeof(float));
887

    
888
    for (i = 0; i < 3; i++) {
889
        int m = 4*mtab->size/mtab->fmode[i].sub;
890
        double freq = 2*M_PI/m;
891
        tctx->cos_tabs[i] = av_malloc((m/4)*sizeof(*tctx->cos_tabs));
892

    
893
        for (j = 0; j <= m/8; j++)
894
            tctx->cos_tabs[i][j] = cos((2*j + 1)*freq);
895
        for (j = 1; j <  m/8; j++)
896
            tctx->cos_tabs[i][m/4-j] = tctx->cos_tabs[i][j];
897
    }
898

    
899

    
900
    ff_init_ff_sine_windows(av_log2(size_m));
901
    ff_init_ff_sine_windows(av_log2(size_s/2));
902
    ff_init_ff_sine_windows(av_log2(mtab->size));
903
}
904

    
905
/**
906
 * Interpret the data as if it were a num_blocks x line_len[0] matrix and for
907
 * each line do a cyclic permutation, i.e.
908
 * abcdefghijklm -> defghijklmabc
909
 * where the amount to be shifted is evaluated depending on the column.
910
 */
911
static void permutate_in_line(int16_t *tab, int num_vect, int num_blocks,
912
                              int block_size,
913
                              const uint8_t line_len[2], int length_div,
914
                              enum FrameType ftype)
915

    
916
{
917
    int i,j;
918

    
919
    for (i = 0; i < line_len[0]; i++) {
920
        int shift;
921

    
922
        if (num_blocks == 1 ||
923
            (ftype == FT_LONG && num_vect % num_blocks) ||
924
            (ftype != FT_LONG && num_vect & 1         ) ||
925
            i == line_len[1]) {
926
            shift = 0;
927
        } else if (ftype == FT_LONG) {
928
            shift = i;
929
        } else
930
            shift = i*i;
931

    
932
        for (j = 0; j < num_vect && (j+num_vect*i < block_size*num_blocks); j++)
933
            tab[i*num_vect+j] = i*num_vect + (j + shift) % num_vect;
934
    }
935
}
936

    
937
/**
938
 * Interpret the input data as in the following table:
939
 *
940
 * \verbatim
941
 *
942
 * abcdefgh
943
 * ijklmnop
944
 * qrstuvw
945
 * x123456
946
 *
947
 * \endverbatim
948
 *
949
 * and transpose it, giving the output
950
 * aiqxbjr1cks2dlt3emu4fvn5gow6hp
951
 */
952
static void transpose_perm(int16_t *out, int16_t *in, int num_vect,
953
                           const uint8_t line_len[2], int length_div)
954
{
955
    int i,j;
956
    int cont= 0;
957
    for (i = 0; i < num_vect; i++)
958
        for (j = 0; j < line_len[i >= length_div]; j++)
959
            out[cont++] = in[j*num_vect + i];
960
}
961

    
962
static void linear_perm(int16_t *out, int16_t *in, int n_blocks, int size)
963
{
964
    int block_size = size/n_blocks;
965
    int i;
966

    
967
    for (i = 0; i < size; i++)
968
        out[i] = block_size * (in[i] % n_blocks) + in[i] / n_blocks;
969
}
970

    
971
static av_cold void construct_perm_table(TwinContext *tctx,enum FrameType ftype)
972
{
973
    int block_size;
974
    const ModeTab *mtab = tctx->mtab;
975
    int size = tctx->avctx->channels*mtab->fmode[ftype].sub;
976
    int16_t *tmp_perm = (int16_t *) tctx->tmp_buf;
977

    
978
    if (ftype == FT_PPC) {
979
        size  = tctx->avctx->channels;
980
        block_size = mtab->ppc_shape_len;
981
    } else
982
        block_size = mtab->size / mtab->fmode[ftype].sub;
983

    
984
    permutate_in_line(tmp_perm, tctx->n_div[ftype], size,
985
                      block_size, tctx->length[ftype],
986
                      tctx->length_change[ftype], ftype);
987

    
988
    transpose_perm(tctx->permut[ftype], tmp_perm, tctx->n_div[ftype],
989
                   tctx->length[ftype], tctx->length_change[ftype]);
990

    
991
    linear_perm(tctx->permut[ftype], tctx->permut[ftype], size,
992
                size*block_size);
993
}
994

    
995
static av_cold void init_bitstream_params(TwinContext *tctx)
996
{
997
    const ModeTab *mtab = tctx->mtab;
998
    int n_ch = tctx->avctx->channels;
999
    int total_fr_bits = tctx->avctx->bit_rate*mtab->size/
1000
                             tctx->avctx->sample_rate;
1001

    
1002
    int lsp_bits_per_block = n_ch*(mtab->lsp_bit0 + mtab->lsp_bit1 +
1003
                                   mtab->lsp_split*mtab->lsp_bit2);
1004

    
1005
    int ppc_bits = n_ch*(mtab->pgain_bit + mtab->ppc_shape_bit +
1006
                         mtab->ppc_period_bit);
1007

    
1008
    int bsize_no_main_cb[3];
1009
    int bse_bits[3];
1010
    int i;
1011
    enum FrameType frametype;
1012

    
1013
    for (i = 0; i < 3; i++)
1014
        // +1 for history usage switch
1015
        bse_bits[i] = n_ch *
1016
            (mtab->fmode[i].bark_n_coef * mtab->fmode[i].bark_n_bit + 1);
1017

    
1018
    bsize_no_main_cb[2] = bse_bits[2] + lsp_bits_per_block + ppc_bits +
1019
                          WINDOW_TYPE_BITS + n_ch*GAIN_BITS;
1020

    
1021
    for (i = 0; i < 2; i++)
1022
        bsize_no_main_cb[i] =
1023
            lsp_bits_per_block + n_ch*GAIN_BITS + WINDOW_TYPE_BITS +
1024
            mtab->fmode[i].sub*(bse_bits[i] + n_ch*SUB_GAIN_BITS);
1025

    
1026
    // The remaining bits are all used for the main spectrum coefficients
1027
    for (i = 0; i < 4; i++) {
1028
        int bit_size;
1029
        int vect_size;
1030
        int rounded_up, rounded_down, num_rounded_down, num_rounded_up;
1031
        if (i == 3) {
1032
            bit_size  = n_ch * mtab->ppc_shape_bit;
1033
            vect_size = n_ch * mtab->ppc_shape_len;
1034
        } else {
1035
            bit_size = total_fr_bits - bsize_no_main_cb[i];
1036
            vect_size = n_ch * mtab->size;
1037
        }
1038

    
1039
        tctx->n_div[i] = (bit_size + 13) / 14;
1040

    
1041
        rounded_up   = (bit_size + tctx->n_div[i] - 1)/tctx->n_div[i];
1042
        rounded_down = (bit_size           )/tctx->n_div[i];
1043
        num_rounded_down = rounded_up * tctx->n_div[i] - bit_size;
1044
        num_rounded_up = tctx->n_div[i] - num_rounded_down;
1045
        tctx->bits_main_spec[0][i][0] = (rounded_up   + 1)/2;
1046
        tctx->bits_main_spec[1][i][0] = (rounded_up      )/2;
1047
        tctx->bits_main_spec[0][i][1] = (rounded_down + 1)/2;
1048
        tctx->bits_main_spec[1][i][1] = (rounded_down    )/2;
1049
        tctx->bits_main_spec_change[i] = num_rounded_up;
1050

    
1051
        rounded_up   = (vect_size + tctx->n_div[i] - 1)/tctx->n_div[i];
1052
        rounded_down = (vect_size                     )/tctx->n_div[i];
1053
        num_rounded_down = rounded_up * tctx->n_div[i] - vect_size;
1054
        num_rounded_up = tctx->n_div[i] - num_rounded_down;
1055
        tctx->length[i][0] = rounded_up;
1056
        tctx->length[i][1] = rounded_down;
1057
        tctx->length_change[i] = num_rounded_up;
1058
    }
1059

    
1060
    for (frametype = FT_SHORT; frametype <= FT_PPC; frametype++)
1061
        construct_perm_table(tctx, frametype);
1062
}
1063

    
1064
static av_cold int twin_decode_init(AVCodecContext *avctx)
1065
{
1066
    TwinContext *tctx = avctx->priv_data;
1067
    int isampf = avctx->sample_rate/1000;
1068
    int ibps = avctx->bit_rate/(1000 * avctx->channels);
1069

    
1070
    tctx->avctx       = avctx;
1071
    avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1072

    
1073
    if (avctx->channels > CHANNELS_MAX) {
1074
        av_log(avctx, AV_LOG_ERROR, "Unsupported number of channels: %i\n",
1075
               avctx->channels);
1076
        return -1;
1077
    }
1078

    
1079
    switch ((isampf << 8) +  ibps) {
1080
    case (8 <<8) +  8: tctx->mtab = &mode_08_08; break;
1081
    case (11<<8) +  8: tctx->mtab = &mode_11_08; break;
1082
    case (11<<8) + 10: tctx->mtab = &mode_11_10; break;
1083
    case (16<<8) + 16: tctx->mtab = &mode_16_16; break;
1084
    case (22<<8) + 20: tctx->mtab = &mode_22_20; break;
1085
    case (22<<8) + 24: tctx->mtab = &mode_22_24; break;
1086
    case (22<<8) + 32: tctx->mtab = &mode_22_32; break;
1087
    case (44<<8) + 40: tctx->mtab = &mode_44_40; break;
1088
    case (44<<8) + 48: tctx->mtab = &mode_44_48; break;
1089
    default:
1090
        av_log(avctx, AV_LOG_ERROR, "This version does not support %d kHz - %d kbit/s/ch mode.\n", isampf, isampf);
1091
        return -1;
1092
    }
1093

    
1094
    dsputil_init(&tctx->dsp, avctx);
1095
    init_mdct_win(tctx);
1096
    init_bitstream_params(tctx);
1097

    
1098
    memset_float(tctx->bark_hist[0][0], 0.1, FF_ARRAY_ELEMS(tctx->bark_hist));
1099

    
1100
    return 0;
1101
}
1102

    
1103
static av_cold int twin_decode_close(AVCodecContext *avctx)
1104
{
1105
    TwinContext *tctx = avctx->priv_data;
1106
    int i;
1107

    
1108
    for (i = 0; i < 3; i++) {
1109
        ff_mdct_end(&tctx->mdct_ctx[i]);
1110
        av_free(tctx->cos_tabs[i]);
1111
    }
1112

    
1113

    
1114
    av_free(tctx->curr_frame);
1115
    av_free(tctx->spectrum);
1116
    av_free(tctx->prev_frame);
1117
    av_free(tctx->tmp_buf);
1118

    
1119
    return 0;
1120
}
1121

    
1122
AVCodec ff_twinvq_decoder =
1123
{
1124
    "twinvq",
1125
    AVMEDIA_TYPE_AUDIO,
1126
    CODEC_ID_TWINVQ,
1127
    sizeof(TwinContext),
1128
    twin_decode_init,
1129
    NULL,
1130
    twin_decode_close,
1131
    twin_decode_frame,
1132
    .long_name = NULL_IF_CONFIG_SMALL("VQF TwinVQ"),
1133
};