libavcodec/twinvq.h

   1 /*
   2  * TwinVQ decoder
   3  * Copyright (c) 2009 Vitor Sessak
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef AVCODEC_TWINVQ_H
  23 #define AVCODEC_TWINVQ_H
  24
  25 #include <math.h>
  26 #include <stdint.h>
  27
  28 #include "libavutil/attributes_internal.h"
  29 #include "libavutil/tx.h"
  30 #include "libavutil/common.h"
  31 #include "libavutil/float_dsp.h"
  32 #include "avcodec.h"
  33
  34 enum TwinVQCodec {
  35     TWINVQ_CODEC_VQF,
  36     TWINVQ_CODEC_METASOUND,
  37 };
  38
  39 enum TwinVQFrameType {
  40     TWINVQ_FT_SHORT = 0,  ///< Short frame  (divided in n   sub-blocks)
  41     TWINVQ_FT_MEDIUM,     ///< Medium frame (divided in m<n sub-blocks)
  42     TWINVQ_FT_LONG,       ///< Long frame   (single sub-block + PPC)
  43     TWINVQ_FT_PPC,        ///< Periodic Peak Component (part of the long frame)
  44 };
  45
  46 #define TWINVQ_PPC_SHAPE_CB_SIZE 64
  47 #define TWINVQ_PPC_SHAPE_LEN_MAX 60
  48 #define TWINVQ_SUB_AMP_MAX       4500.0
  49 #define TWINVQ_MULAW_MU          100.0
  50 #define TWINVQ_GAIN_BITS         8
  51 #define TWINVQ_AMP_MAX           13000.0
  52 #define TWINVQ_SUB_GAIN_BITS     5
  53 #define TWINVQ_WINDOW_TYPE_BITS  4
  54 #define TWINVQ_PGAIN_MU          200
  55 #define TWINVQ_LSP_COEFS_MAX     20
  56 #define TWINVQ_LSP_SPLIT_MAX     4
  57 #define TWINVQ_CHANNELS_MAX      2
  58 #define TWINVQ_SUBBLOCKS_MAX     16
  59 #define TWINVQ_BARK_N_COEF_MAX   4
  60
  61 #define TWINVQ_MAX_FRAMES_PER_PACKET 2
  62
  63 /**
  64  * Parameters and tables that are different for each frame type
  65  */
  66 struct TwinVQFrameMode {
  67     uint8_t         sub;      ///< Number subblocks in each frame
  68     const uint16_t *bark_tab;
  69
  70     /** number of distinct bark scale envelope values */
  71     uint8_t         bark_env_size;
  72
  73     const int16_t  *bark_cb;    ///< codebook for the bark scale envelope (BSE)
  74     uint8_t         bark_n_coef;///< number of BSE CB coefficients to read
  75     uint8_t         bark_n_bit; ///< number of bits of the BSE coefs
  76
  77     //@{
  78     /** main codebooks for spectrum data */
  79     const int16_t    *cb0;
  80     const int16_t    *cb1;
  81     //@}
  82
  83     uint8_t         cb_len_read; ///< number of spectrum coefficients to read
  84 };
  85
  86 typedef struct TwinVQFrameData {
  87     int     window_type;
  88     enum TwinVQFrameType ftype;
  89
  90     uint8_t main_coeffs[1024];
  91     uint8_t ppc_coeffs[TWINVQ_PPC_SHAPE_LEN_MAX];
  92
  93     uint8_t gain_bits[TWINVQ_CHANNELS_MAX];
  94     uint8_t sub_gain_bits[TWINVQ_CHANNELS_MAX * TWINVQ_SUBBLOCKS_MAX];
  95
  96     uint8_t bark1[TWINVQ_CHANNELS_MAX][TWINVQ_SUBBLOCKS_MAX][TWINVQ_BARK_N_COEF_MAX];
  97     uint8_t bark_use_hist[TWINVQ_CHANNELS_MAX][TWINVQ_SUBBLOCKS_MAX];
  98
  99     uint8_t lpc_idx1[TWINVQ_CHANNELS_MAX];
 100     uint8_t lpc_idx2[TWINVQ_CHANNELS_MAX][TWINVQ_LSP_SPLIT_MAX];
 101     uint8_t lpc_hist_idx[TWINVQ_CHANNELS_MAX];
 102
 103     int     p_coef[TWINVQ_CHANNELS_MAX];
 104     int     g_coef[TWINVQ_CHANNELS_MAX];
 105 } TwinVQFrameData;
 106
 107 /**
 108  * Parameters and tables that are different for every combination of
 109  * bitrate/sample rate
 110  */
 111 typedef struct TwinVQModeTab {
 112     struct TwinVQFrameMode fmode[3]; ///< frame type-dependent parameters
 113
 114     uint16_t     size;        ///< frame size in samples
 115     uint8_t      n_lsp;       ///< number of lsp coefficients
 116     const float *lspcodebook;
 117
 118     /* number of bits of the different LSP CB coefficients */
 119     uint8_t      lsp_bit0;
 120     uint8_t      lsp_bit1;
 121     uint8_t      lsp_bit2;
 122
 123     uint8_t      lsp_split;      ///< number of CB entries for the LSP decoding
 124     const int16_t *ppc_shape_cb; ///< PPC shape CB
 125
 126     /** number of the bits for the PPC period value */
 127     uint8_t      ppc_period_bit;
 128
 129     uint8_t      ppc_shape_bit;  ///< number of bits of the PPC shape CB coeffs
 130     uint8_t      ppc_shape_len;  ///< size of PPC shape CB
 131     uint8_t      pgain_bit;      ///< bits for PPC gain
 132
 133     /** constant for peak period to peak width conversion */
 134     uint16_t     peak_per2wid;
 135 } TwinVQModeTab;
 136
 137 typedef struct TwinVQContext {
 138     AVCodecContext *avctx;
 139     AVFloatDSPContext *fdsp;
 140     AVTXContext *tx[3];
 141     av_tx_fn tx_fn[3];
 142
 143     const TwinVQModeTab *mtab;
 144
 145     int is_6kbps;
 146
 147     // history
 148     float lsp_hist[2][20];           ///< LSP coefficients of the last frame
 149     float bark_hist[3][2][40];       ///< BSE coefficients of last frame
 150
 151     // bitstream parameters
 152     int16_t permut[4][4096];
 153     uint8_t length[4][2];            ///< main codebook stride
 154     uint8_t length_change[4];
 155     uint8_t bits_main_spec[2][4][2]; ///< bits for the main codebook
 156     int bits_main_spec_change[4];
 157     int n_div[4];
 158
 159     float *spectrum;
 160     float *curr_frame;               ///< non-interleaved output
 161     float *prev_frame;               ///< non-interleaved previous frame
 162     int last_block_pos[2];
 163     int discarded_packets;
 164
 165     float *cos_tabs[3];
 166
 167     // scratch buffers
 168     float *tmp_buf;
 169
 170     int frame_size, frames_per_packet, cur_frame;
 171     TwinVQFrameData bits[TWINVQ_MAX_FRAMES_PER_PACKET];
 172
 173     enum TwinVQCodec codec;
 174
 175     int (*read_bitstream)(AVCodecContext *avctx, struct TwinVQContext *tctx,
 176                           const uint8_t *buf, int buf_size);
 177     void (*dec_bark_env)(struct TwinVQContext *tctx, const uint8_t *in,
 178                          int use_hist, int ch, float *out, float gain,
 179                          enum TwinVQFrameType ftype);
 180     void (*decode_ppc)(struct TwinVQContext *tctx, int period_coef, int g_coef,
 181                        const float *shape, float *speech);
 182 } TwinVQContext;
 183
 184 FF_VISIBILITY_PUSH_HIDDEN
 185 extern const enum TwinVQFrameType ff_twinvq_wtype_to_ftype_table[];
 186
 187 extern const float ff_metasound_lsp8[];
 188 extern const float ff_metasound_lsp11[];
 189 extern const float ff_metasound_lsp16[];
 190 extern const float ff_metasound_lsp22[];
 191 extern const float ff_metasound_lsp44[];
 192
 193 /** @note not speed critical, hence not optimized */
 194 static inline void twinvq_memset_float(float *buf, float val, int size)
 195 {
 196     while (size--)
 197         *buf++ = val;
 198 }
 199
 200 static inline float twinvq_mulawinv(float y, float clip, float mu)
 201 {
 202     y = av_clipf(y / clip, -1, 1);
 203     return clip * FFSIGN(y) * (exp(log(1 + mu) * fabs(y)) - 1) / mu;
 204 }
 205
 206 int ff_twinvq_decode_frame(AVCodecContext *avctx, AVFrame *frame,
 207                            int *got_frame_ptr, AVPacket *avpkt);
 208 int ff_twinvq_decode_close(AVCodecContext *avctx);
 209 /** Requires the caller to call ff_twinvq_decode_close() upon failure. */
 210 int ff_twinvq_decode_init(AVCodecContext *avctx);
 211 FF_VISIBILITY_POP_HIDDEN
 212
 213 #endif /* AVCODEC_TWINVQ_H */