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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 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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/**
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 * 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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    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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    // scratch buffers
201
    float *tmp_buf;
202
} TwinContext;
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204
#define PPC_SHAPE_CB_SIZE 64
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#define PPC_SHAPE_LEN_MAX 60
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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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#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
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#define BARK_N_COEF_MAX   4
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/** @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;
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}
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/**
227
 * Evaluate a single LPC amplitude spectrum envelope coefficient from the line
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 * spectrum pairs.
229
 *
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 * @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
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;
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250
        q *= lsp[j+2] - two_cos_w;
251
        p *= lsp[j+3] - two_cos_w;
252
    }
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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
}
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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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/**
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
    const ModeTab *mtab = tctx->mtab;
612
    int bsize = mtab->size / mtab->fmode[ftype].sub;
613
    int size  = mtab->size;
614
    float *buf1 = tctx->tmp_buf;
615
    int j;
616
    int wsize; // Window size
617
    float *out = tctx->curr_frame + 2*ch*mtab->size;
618
    float *out2 = out;
619
    float *prev_buf;
620
    int first_wsize;
621

    
622
    static const uint8_t wtype_to_wsize[]      = {0, 0, 2, 2, 2, 1, 0, 1, 1};
623
    int types_sizes[] = {
624
        mtab->size /    mtab->fmode[FT_LONG  ].sub,
625
        mtab->size /    mtab->fmode[FT_MEDIUM].sub,
626
        mtab->size / (2*mtab->fmode[FT_SHORT ].sub),
627
    };
628

    
629
    wsize = types_sizes[wtype_to_wsize[wtype]];
630
    first_wsize = wsize;
631
    prev_buf = prev + (size - bsize)/2;
632

    
633
    for (j = 0; j < mtab->fmode[ftype].sub; j++) {
634
        int sub_wtype = ftype == FT_MEDIUM ? 8 : wtype;
635

    
636
        if (!j && wtype == 4)
637
            sub_wtype = 4;
638
        else if (j == mtab->fmode[ftype].sub-1 && wtype == 7)
639
            sub_wtype = 7;
640

    
641
        wsize = types_sizes[wtype_to_wsize[sub_wtype]];
642

    
643
        ff_imdct_half(&tctx->mdct_ctx[ftype], buf1 + bsize*j, in + bsize*j);
644

    
645
        tctx->dsp.vector_fmul_window(out2,
646
                                     prev_buf + (bsize-wsize)/2,
647
                                     buf1 + bsize*j,
648
                                     ff_sine_windows[av_log2(wsize)],
649
                                     wsize/2);
650
        out2 += wsize;
651

    
652
        memcpy(out2, buf1 + bsize*j + wsize/2, (bsize - wsize/2)*sizeof(float));
653

    
654
        out2 += ftype == FT_MEDIUM ? (bsize-wsize)/2 : bsize - wsize;
655

    
656
        prev_buf = buf1 + bsize*j + bsize/2;
657
    }
658

    
659
    tctx->last_block_pos[ch] = (size + first_wsize)/2;
660
}
661

    
662
static void imdct_output(TwinContext *tctx, enum FrameType ftype, int wtype,
663
                         float *out)
664
{
665
    const ModeTab *mtab = tctx->mtab;
666
    float *prev_buf = tctx->prev_frame + tctx->last_block_pos[0];
667
    int i, j;
668

    
669
    for (i = 0; i < tctx->avctx->channels; i++) {
670
        imdct_and_window(tctx, ftype, wtype,
671
                         tctx->spectrum + i*mtab->size,
672
                         prev_buf + 2*i*mtab->size,
673
                         i);
674
    }
675

    
676
    if (tctx->avctx->channels == 2) {
677
        for (i = 0; i < mtab->size - tctx->last_block_pos[0]; i++) {
678
            float f1 = prev_buf[               i];
679
            float f2 = prev_buf[2*mtab->size + i];
680
            out[2*i    ] = f1 + f2;
681
            out[2*i + 1] = f1 - f2;
682
        }
683
        for (j = 0; i < mtab->size; j++,i++) {
684
            float f1 = tctx->curr_frame[               j];
685
            float f2 = tctx->curr_frame[2*mtab->size + j];
686
            out[2*i    ] = f1 + f2;
687
            out[2*i + 1] = f1 - f2;
688
        }
689
    } else {
690
        memcpy(out, prev_buf,
691
               (mtab->size - tctx->last_block_pos[0]) * sizeof(*out));
692

    
693
        out +=  mtab->size - tctx->last_block_pos[0];
694

    
695
        memcpy(out, tctx->curr_frame,
696
               (tctx->last_block_pos[0]) * sizeof(*out));
697
    }
698

    
699
}
700

    
701
static void dec_bark_env(TwinContext *tctx, const uint8_t *in, int use_hist,
702
                         int ch, float *out, float gain, enum FrameType ftype)
703
{
704
    const ModeTab *mtab = tctx->mtab;
705
    int i,j;
706
    float *hist = tctx->bark_hist[ftype][ch];
707
    float val = ((const float []) {0.4, 0.35, 0.28})[ftype];
708
    int bark_n_coef  = mtab->fmode[ftype].bark_n_coef;
709
    int fw_cb_len = mtab->fmode[ftype].bark_env_size / bark_n_coef;
710
    int idx = 0;
711

    
712
    for (i = 0; i < fw_cb_len; i++)
713
        for (j = 0; j < bark_n_coef; j++, idx++) {
714
            float tmp2 =
715
                mtab->fmode[ftype].bark_cb[fw_cb_len*in[j] + i] * (1./4096);
716
            float st = use_hist ?
717
                (1. - val) * tmp2 + val*hist[idx] + 1. : tmp2 + 1.;
718

    
719
            hist[idx] = tmp2;
720
            if (st < -1.) st = 1.;
721

    
722
            memset_float(out, st * gain, mtab->fmode[ftype].bark_tab[idx]);
723
            out += mtab->fmode[ftype].bark_tab[idx];
724
        }
725

    
726
}
727

    
728
static void read_and_decode_spectrum(TwinContext *tctx, GetBitContext *gb,
729
                                     float *out, enum FrameType ftype)
730
{
731
    const ModeTab *mtab = tctx->mtab;
732
    int channels = tctx->avctx->channels;
733
    int sub = mtab->fmode[ftype].sub;
734
    int block_size = mtab->size / sub;
735
    float gain[CHANNELS_MAX*SUBBLOCKS_MAX];
736
    float ppc_shape[PPC_SHAPE_LEN_MAX * CHANNELS_MAX * 4];
737
    uint8_t bark1[CHANNELS_MAX][SUBBLOCKS_MAX][BARK_N_COEF_MAX];
738
    uint8_t bark_use_hist[CHANNELS_MAX][SUBBLOCKS_MAX];
739

    
740
    uint8_t lpc_idx1[CHANNELS_MAX];
741
    uint8_t lpc_idx2[CHANNELS_MAX][LSP_SPLIT_MAX];
742
    uint8_t lpc_hist_idx[CHANNELS_MAX];
743

    
744
    int i, j, k;
745

    
746
    dequant(tctx, gb, out, ftype,
747
            mtab->fmode[ftype].cb0, mtab->fmode[ftype].cb1,
748
            mtab->fmode[ftype].cb_len_read);
749

    
750
    for (i = 0; i < channels; i++)
751
        for (j = 0; j < sub; j++)
752
            for (k = 0; k < mtab->fmode[ftype].bark_n_coef; k++)
753
                bark1[i][j][k] =
754
                    get_bits(gb, mtab->fmode[ftype].bark_n_bit);
755

    
756
    for (i = 0; i < channels; i++)
757
        for (j = 0; j < sub; j++)
758
            bark_use_hist[i][j] = get_bits1(gb);
759

    
760
    dec_gain(tctx, gb, ftype, gain);
761

    
762
    for (i = 0; i < channels; i++) {
763
        lpc_hist_idx[i] = get_bits(gb, tctx->mtab->lsp_bit0);
764
        lpc_idx1    [i] = get_bits(gb, tctx->mtab->lsp_bit1);
765

    
766
        for (j = 0; j < tctx->mtab->lsp_split; j++)
767
            lpc_idx2[i][j] = get_bits(gb, tctx->mtab->lsp_bit2);
768
    }
769

    
770
    if (ftype == FT_LONG) {
771
        int cb_len_p = (tctx->n_div[3] + mtab->ppc_shape_len*channels - 1)/
772
            tctx->n_div[3];
773
        dequant(tctx, gb, ppc_shape, FT_PPC, mtab->ppc_shape_cb,
774
                mtab->ppc_shape_cb + cb_len_p*PPC_SHAPE_CB_SIZE, cb_len_p);
775
    }
776

    
777
    for (i = 0; i < channels; i++) {
778
        float *chunk = out + mtab->size * i;
779
        float lsp[LSP_COEFS_MAX];
780

    
781
        for (j = 0; j < sub; j++) {
782
            dec_bark_env(tctx, bark1[i][j], bark_use_hist[i][j], i,
783
                         tctx->tmp_buf, gain[sub*i+j], ftype);
784

    
785
            tctx->dsp.vector_fmul(chunk + block_size*j, chunk + block_size*j, tctx->tmp_buf,
786
                                  block_size);
787

    
788
        }
789

    
790
        if (ftype == FT_LONG) {
791
            float pgain_step = 25000. / ((1 << mtab->pgain_bit) - 1);
792
            int p_coef = get_bits(gb, tctx->mtab->ppc_period_bit);
793
            int g_coef = get_bits(gb, tctx->mtab->pgain_bit);
794
            float v = 1./8192*
795
                mulawinv(pgain_step*g_coef+ pgain_step/2, 25000., PGAIN_MU);
796

    
797
            decode_ppc(tctx, p_coef, ppc_shape + i*mtab->ppc_shape_len, v,
798
                       chunk);
799
        }
800

    
801
        decode_lsp(tctx, lpc_idx1[i], lpc_idx2[i], lpc_hist_idx[i], lsp,
802
                   tctx->lsp_hist[i]);
803

    
804
        dec_lpc_spectrum_inv(tctx, lsp, ftype, tctx->tmp_buf);
805

    
806
        for (j = 0; j < mtab->fmode[ftype].sub; j++) {
807
            tctx->dsp.vector_fmul(chunk, chunk, tctx->tmp_buf, block_size);
808
            chunk += block_size;
809
        }
810
    }
811
}
812

    
813
static int twin_decode_frame(AVCodecContext * avctx, void *data,
814
                             int *data_size, AVPacket *avpkt)
815
{
816
    const uint8_t *buf = avpkt->data;
817
    int buf_size = avpkt->size;
818
    TwinContext *tctx = avctx->priv_data;
819
    GetBitContext gb;
820
    const ModeTab *mtab = tctx->mtab;
821
    float *out = data;
822
    enum FrameType ftype;
823
    int window_type;
824
    static const enum FrameType wtype_to_ftype_table[] = {
825
        FT_LONG,   FT_LONG, FT_SHORT, FT_LONG,
826
        FT_MEDIUM, FT_LONG, FT_LONG,  FT_MEDIUM, FT_MEDIUM
827
    };
828

    
829
    if (buf_size*8 < avctx->bit_rate*mtab->size/avctx->sample_rate + 8) {
830
        av_log(avctx, AV_LOG_ERROR,
831
               "Frame too small (%d bytes). Truncated file?\n", buf_size);
832
        *data_size = 0;
833
        return buf_size;
834
    }
835

    
836
    init_get_bits(&gb, buf, buf_size * 8);
837
    skip_bits(&gb, get_bits(&gb, 8));
838
    window_type = get_bits(&gb, WINDOW_TYPE_BITS);
839

    
840
    if (window_type > 8) {
841
        av_log(avctx, AV_LOG_ERROR, "Invalid window type, broken sample?\n");
842
        return -1;
843
    }
844

    
845
    ftype = wtype_to_ftype_table[window_type];
846

    
847
    read_and_decode_spectrum(tctx, &gb, tctx->spectrum, ftype);
848

    
849
    imdct_output(tctx, ftype, window_type, out);
850

    
851
    FFSWAP(float*, tctx->curr_frame, tctx->prev_frame);
852

    
853
    if (tctx->avctx->frame_number < 2) {
854
        *data_size=0;
855
        return buf_size;
856
    }
857

    
858
    *data_size = mtab->size*avctx->channels*4;
859

    
860
    return buf_size;
861
}
862

    
863
/**
864
 * Init IMDCT and windowing tables
865
 */
866
static av_cold void init_mdct_win(TwinContext *tctx)
867
{
868
    int i,j;
869
    const ModeTab *mtab = tctx->mtab;
870
    int size_s = mtab->size / mtab->fmode[FT_SHORT].sub;
871
    int size_m = mtab->size / mtab->fmode[FT_MEDIUM].sub;
872
    int channels = tctx->avctx->channels;
873
    float norm = channels == 1 ? 2. : 1.;
874

    
875
    for (i = 0; i < 3; i++) {
876
        int bsize = tctx->mtab->size/tctx->mtab->fmode[i].sub;
877
        ff_mdct_init(&tctx->mdct_ctx[i], av_log2(bsize) + 1, 1,
878
                     -sqrt(norm/bsize) / (1<<15));
879
    }
880

    
881
    tctx->tmp_buf  = av_malloc(mtab->size            * sizeof(*tctx->tmp_buf));
882

    
883
    tctx->spectrum  = av_malloc(2*mtab->size*channels*sizeof(float));
884
    tctx->curr_frame = av_malloc(2*mtab->size*channels*sizeof(float));
885
    tctx->prev_frame  = av_malloc(2*mtab->size*channels*sizeof(float));
886

    
887
    for (i = 0; i < 3; i++) {
888
        int m = 4*mtab->size/mtab->fmode[i].sub;
889
        double freq = 2*M_PI/m;
890
        tctx->cos_tabs[i] = av_malloc((m/4)*sizeof(*tctx->cos_tabs));
891

    
892
        for (j = 0; j <= m/8; j++)
893
            tctx->cos_tabs[i][j] = cos((2*j + 1)*freq);
894
        for (j = 1; j <  m/8; j++)
895
            tctx->cos_tabs[i][m/4-j] = tctx->cos_tabs[i][j];
896
    }
897

    
898

    
899
    ff_init_ff_sine_windows(av_log2(size_m));
900
    ff_init_ff_sine_windows(av_log2(size_s/2));
901
    ff_init_ff_sine_windows(av_log2(mtab->size));
902
}
903

    
904
/**
905
 * Interpret the data as if it were a num_blocks x line_len[0] matrix and for
906
 * each line do a cyclic permutation, i.e.
907
 * abcdefghijklm -> defghijklmabc
908
 * where the amount to be shifted is evaluated depending on the column.
909
 */
910
static void permutate_in_line(int16_t *tab, int num_vect, int num_blocks,
911
                              int block_size,
912
                              const uint8_t line_len[2], int length_div,
913
                              enum FrameType ftype)
914

    
915
{
916
    int i,j;
917

    
918
    for (i = 0; i < line_len[0]; i++) {
919
        int shift;
920

    
921
        if (num_blocks == 1 ||
922
            (ftype == FT_LONG && num_vect % num_blocks) ||
923
            (ftype != FT_LONG && num_vect & 1         ) ||
924
            i == line_len[1]) {
925
            shift = 0;
926
        } else if (ftype == FT_LONG) {
927
            shift = i;
928
        } else
929
            shift = i*i;
930

    
931
        for (j = 0; j < num_vect && (j+num_vect*i < block_size*num_blocks); j++)
932
            tab[i*num_vect+j] = i*num_vect + (j + shift) % num_vect;
933
    }
934
}
935

    
936
/**
937
 * Interpret the input data as in the following table:
938
 *
939
 * \verbatim
940
 *
941
 * abcdefgh
942
 * ijklmnop
943
 * qrstuvw
944
 * x123456
945
 *
946
 * \endverbatim
947
 *
948
 * and transpose it, giving the output
949
 * aiqxbjr1cks2dlt3emu4fvn5gow6hp
950
 */
951
static void transpose_perm(int16_t *out, int16_t *in, int num_vect,
952
                           const uint8_t line_len[2], int length_div)
953
{
954
    int i,j;
955
    int cont= 0;
956
    for (i = 0; i < num_vect; i++)
957
        for (j = 0; j < line_len[i >= length_div]; j++)
958
            out[cont++] = in[j*num_vect + i];
959
}
960

    
961
static void linear_perm(int16_t *out, int16_t *in, int n_blocks, int size)
962
{
963
    int block_size = size/n_blocks;
964
    int i;
965

    
966
    for (i = 0; i < size; i++)
967
        out[i] = block_size * (in[i] % n_blocks) + in[i] / n_blocks;
968
}
969

    
970
static av_cold void construct_perm_table(TwinContext *tctx,enum FrameType ftype)
971
{
972
    int block_size;
973
    const ModeTab *mtab = tctx->mtab;
974
    int size = tctx->avctx->channels*mtab->fmode[ftype].sub;
975
    int16_t *tmp_perm = (int16_t *) tctx->tmp_buf;
976

    
977
    if (ftype == FT_PPC) {
978
        size  = tctx->avctx->channels;
979
        block_size = mtab->ppc_shape_len;
980
    } else
981
        block_size = mtab->size / mtab->fmode[ftype].sub;
982

    
983
    permutate_in_line(tmp_perm, tctx->n_div[ftype], size,
984
                      block_size, tctx->length[ftype],
985
                      tctx->length_change[ftype], ftype);
986

    
987
    transpose_perm(tctx->permut[ftype], tmp_perm, tctx->n_div[ftype],
988
                   tctx->length[ftype], tctx->length_change[ftype]);
989

    
990
    linear_perm(tctx->permut[ftype], tctx->permut[ftype], size,
991
                size*block_size);
992
}
993

    
994
static av_cold void init_bitstream_params(TwinContext *tctx)
995
{
996
    const ModeTab *mtab = tctx->mtab;
997
    int n_ch = tctx->avctx->channels;
998
    int total_fr_bits = tctx->avctx->bit_rate*mtab->size/
999
                             tctx->avctx->sample_rate;
1000

    
1001
    int lsp_bits_per_block = n_ch*(mtab->lsp_bit0 + mtab->lsp_bit1 +
1002
                                   mtab->lsp_split*mtab->lsp_bit2);
1003

    
1004
    int ppc_bits = n_ch*(mtab->pgain_bit + mtab->ppc_shape_bit +
1005
                         mtab->ppc_period_bit);
1006

    
1007
    int bsize_no_main_cb[3];
1008
    int bse_bits[3];
1009
    int i;
1010
    enum FrameType frametype;
1011

    
1012
    for (i = 0; i < 3; i++)
1013
        // +1 for history usage switch
1014
        bse_bits[i] = n_ch *
1015
            (mtab->fmode[i].bark_n_coef * mtab->fmode[i].bark_n_bit + 1);
1016

    
1017
    bsize_no_main_cb[2] = bse_bits[2] + lsp_bits_per_block + ppc_bits +
1018
                          WINDOW_TYPE_BITS + n_ch*GAIN_BITS;
1019

    
1020
    for (i = 0; i < 2; i++)
1021
        bsize_no_main_cb[i] =
1022
            lsp_bits_per_block + n_ch*GAIN_BITS + WINDOW_TYPE_BITS +
1023
            mtab->fmode[i].sub*(bse_bits[i] + n_ch*SUB_GAIN_BITS);
1024

    
1025
    // The remaining bits are all used for the main spectrum coefficients
1026
    for (i = 0; i < 4; i++) {
1027
        int bit_size;
1028
        int vect_size;
1029
        int rounded_up, rounded_down, num_rounded_down, num_rounded_up;
1030
        if (i == 3) {
1031
            bit_size  = n_ch * mtab->ppc_shape_bit;
1032
            vect_size = n_ch * mtab->ppc_shape_len;
1033
        } else {
1034
            bit_size = total_fr_bits - bsize_no_main_cb[i];
1035
            vect_size = n_ch * mtab->size;
1036
        }
1037

    
1038
        tctx->n_div[i] = (bit_size + 13) / 14;
1039

    
1040
        rounded_up   = (bit_size + tctx->n_div[i] - 1)/tctx->n_div[i];
1041
        rounded_down = (bit_size           )/tctx->n_div[i];
1042
        num_rounded_down = rounded_up * tctx->n_div[i] - bit_size;
1043
        num_rounded_up = tctx->n_div[i] - num_rounded_down;
1044
        tctx->bits_main_spec[0][i][0] = (rounded_up   + 1)/2;
1045
        tctx->bits_main_spec[1][i][0] = (rounded_up      )/2;
1046
        tctx->bits_main_spec[0][i][1] = (rounded_down + 1)/2;
1047
        tctx->bits_main_spec[1][i][1] = (rounded_down    )/2;
1048
        tctx->bits_main_spec_change[i] = num_rounded_up;
1049

    
1050
        rounded_up   = (vect_size + tctx->n_div[i] - 1)/tctx->n_div[i];
1051
        rounded_down = (vect_size                     )/tctx->n_div[i];
1052
        num_rounded_down = rounded_up * tctx->n_div[i] - vect_size;
1053
        num_rounded_up = tctx->n_div[i] - num_rounded_down;
1054
        tctx->length[i][0] = rounded_up;
1055
        tctx->length[i][1] = rounded_down;
1056
        tctx->length_change[i] = num_rounded_up;
1057
    }
1058

    
1059
    for (frametype = FT_SHORT; frametype <= FT_PPC; frametype++)
1060
        construct_perm_table(tctx, frametype);
1061
}
1062

    
1063
static av_cold int twin_decode_init(AVCodecContext *avctx)
1064
{
1065
    TwinContext *tctx = avctx->priv_data;
1066
    int isampf = avctx->sample_rate/1000;
1067
    int ibps = avctx->bit_rate/(1000 * avctx->channels);
1068

    
1069
    tctx->avctx       = avctx;
1070
    avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1071

    
1072
    if (avctx->channels > CHANNELS_MAX) {
1073
        av_log(avctx, AV_LOG_ERROR, "Unsupported number of channels: %i\n",
1074
               avctx->channels);
1075
        return -1;
1076
    }
1077

    
1078
    switch ((isampf << 8) +  ibps) {
1079
    case (8 <<8) +  8: tctx->mtab = &mode_08_08; break;
1080
    case (11<<8) +  8: tctx->mtab = &mode_11_08; break;
1081
    case (11<<8) + 10: tctx->mtab = &mode_11_10; break;
1082
    case (16<<8) + 16: tctx->mtab = &mode_16_16; break;
1083
    case (22<<8) + 20: tctx->mtab = &mode_22_20; break;
1084
    case (22<<8) + 24: tctx->mtab = &mode_22_24; break;
1085
    case (22<<8) + 32: tctx->mtab = &mode_22_32; break;
1086
    case (44<<8) + 40: tctx->mtab = &mode_44_40; break;
1087
    case (44<<8) + 48: tctx->mtab = &mode_44_48; break;
1088
    default:
1089
        av_log(avctx, AV_LOG_ERROR, "This version does not support %d kHz - %d kbit/s/ch mode.\n", isampf, isampf);
1090
        return -1;
1091
    }
1092

    
1093
    dsputil_init(&tctx->dsp, avctx);
1094
    init_mdct_win(tctx);
1095
    init_bitstream_params(tctx);
1096

    
1097
    memset_float(tctx->bark_hist[0][0], 0.1, FF_ARRAY_ELEMS(tctx->bark_hist));
1098

    
1099
    return 0;
1100
}
1101

    
1102
static av_cold int twin_decode_close(AVCodecContext *avctx)
1103
{
1104
    TwinContext *tctx = avctx->priv_data;
1105
    int i;
1106

    
1107
    for (i = 0; i < 3; i++) {
1108
        ff_mdct_end(&tctx->mdct_ctx[i]);
1109
        av_free(tctx->cos_tabs[i]);
1110
    }
1111

    
1112

    
1113
    av_free(tctx->curr_frame);
1114
    av_free(tctx->spectrum);
1115
    av_free(tctx->prev_frame);
1116
    av_free(tctx->tmp_buf);
1117

    
1118
    return 0;
1119
}
1120

    
1121
AVCodec ff_twinvq_decoder =
1122
{
1123
    "twinvq",
1124
    AVMEDIA_TYPE_AUDIO,
1125
    CODEC_ID_TWINVQ,
1126
    sizeof(TwinContext),
1127
    twin_decode_init,
1128
    NULL,
1129
    twin_decode_close,
1130
    twin_decode_frame,
1131
    .long_name = NULL_IF_CONFIG_SMALL("VQF TwinVQ"),
1132
};