/* * TwinVQ decoder * Copyright (c) 2009 Vitor Sessak * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "avcodec.h" #include "get_bits.h" #include "dsputil.h" #include "fft.h" #include "lsp.h" #include "sinewin.h" #include <math.h> #include <stdint.h> #include "twinvq_data.h" enum FrameType { FT_SHORT = 0, ///< Short frame (divided in n sub-blocks) FT_MEDIUM, ///< Medium frame (divided in m<n sub-blocks) FT_LONG, ///< Long frame (single sub-block + PPC) FT_PPC, ///< Periodic Peak Component (part of the long frame) }; /** * Parameters and tables that are different for each frame type */ struct FrameMode { uint8_t sub; ///< Number subblocks in each frame const uint16_t *bark_tab; /** number of distinct bark scale envelope values */ uint8_t bark_env_size; const int16_t *bark_cb; ///< codebook for the bark scale envelope (BSE) uint8_t bark_n_coef;///< number of BSE CB coefficients to read uint8_t bark_n_bit; ///< number of bits of the BSE coefs //@{ /** main codebooks for spectrum data */ const int16_t *cb0; const int16_t *cb1; //@} uint8_t cb_len_read; ///< number of spectrum coefficients to read }; /** * Parameters and tables that are different for every combination of * bitrate/sample rate */ typedef struct { struct FrameMode fmode[3]; ///< frame type-dependant parameters uint16_t size; ///< frame size in samples uint8_t n_lsp; ///< number of lsp coefficients const float *lspcodebook; /* number of bits of the different LSP CB coefficients */ uint8_t lsp_bit0; uint8_t lsp_bit1; uint8_t lsp_bit2; uint8_t lsp_split; ///< number of CB entries for the LSP decoding const int16_t *ppc_shape_cb; ///< PPC shape CB /** number of the bits for the PPC period value */ uint8_t ppc_period_bit; uint8_t ppc_shape_bit; ///< number of bits of the PPC shape CB coeffs uint8_t ppc_shape_len; ///< size of PPC shape CB uint8_t pgain_bit; ///< bits for PPC gain /** constant for peak period to peak width conversion */ uint16_t peak_per2wid; } ModeTab; static const ModeTab mode_08_08 = { { { 8, bark_tab_s08_64, 10, tab.fcb08s , 1, 5, tab.cb0808s0, tab.cb0808s1, 18}, { 2, bark_tab_m08_256, 20, tab.fcb08m , 2, 5, tab.cb0808m0, tab.cb0808m1, 16}, { 1, bark_tab_l08_512, 30, tab.fcb08l , 3, 6, tab.cb0808l0, tab.cb0808l1, 17} }, 512 , 12, tab.lsp08, 1, 5, 3, 3, tab.shape08 , 8, 28, 20, 6, 40 }; static const ModeTab mode_11_08 = { { { 8, bark_tab_s11_64, 10, tab.fcb11s , 1, 5, tab.cb1108s0, tab.cb1108s1, 29}, { 2, bark_tab_m11_256, 20, tab.fcb11m , 2, 5, tab.cb1108m0, tab.cb1108m1, 24}, { 1, bark_tab_l11_512, 30, tab.fcb11l , 3, 6, tab.cb1108l0, tab.cb1108l1, 27} }, 512 , 16, tab.lsp11, 1, 6, 4, 3, tab.shape11 , 9, 36, 30, 7, 90 }; static const ModeTab mode_11_10 = { { { 8, bark_tab_s11_64, 10, tab.fcb11s , 1, 5, tab.cb1110s0, tab.cb1110s1, 21}, { 2, bark_tab_m11_256, 20, tab.fcb11m , 2, 5, tab.cb1110m0, tab.cb1110m1, 18}, { 1, bark_tab_l11_512, 30, tab.fcb11l , 3, 6, tab.cb1110l0, tab.cb1110l1, 20} }, 512 , 16, tab.lsp11, 1, 6, 4, 3, tab.shape11 , 9, 36, 30, 7, 90 }; static const ModeTab mode_16_16 = { { { 8, bark_tab_s16_128, 10, tab.fcb16s , 1, 5, tab.cb1616s0, tab.cb1616s1, 16}, { 2, bark_tab_m16_512, 20, tab.fcb16m , 2, 5, tab.cb1616m0, tab.cb1616m1, 15}, { 1, bark_tab_l16_1024,30, tab.fcb16l , 3, 6, tab.cb1616l0, tab.cb1616l1, 16} }, 1024, 16, tab.lsp16, 1, 6, 4, 3, tab.shape16 , 9, 56, 60, 7, 180 }; static const ModeTab mode_22_20 = { { { 8, bark_tab_s22_128, 10, tab.fcb22s_1, 1, 6, tab.cb2220s0, tab.cb2220s1, 18}, { 2, bark_tab_m22_512, 20, tab.fcb22m_1, 2, 6, tab.cb2220m0, tab.cb2220m1, 17}, { 1, bark_tab_l22_1024,32, tab.fcb22l_1, 4, 6, tab.cb2220l0, tab.cb2220l1, 18} }, 1024, 16, tab.lsp22_1, 1, 6, 4, 3, tab.shape22_1, 9, 56, 36, 7, 144 }; static const ModeTab mode_22_24 = { { { 8, bark_tab_s22_128, 10, tab.fcb22s_1, 1, 6, tab.cb2224s0, tab.cb2224s1, 15}, { 2, bark_tab_m22_512, 20, tab.fcb22m_1, 2, 6, tab.cb2224m0, tab.cb2224m1, 14}, { 1, bark_tab_l22_1024,32, tab.fcb22l_1, 4, 6, tab.cb2224l0, tab.cb2224l1, 15} }, 1024, 16, tab.lsp22_1, 1, 6, 4, 3, tab.shape22_1, 9, 56, 36, 7, 144 }; static const ModeTab mode_22_32 = { { { 4, bark_tab_s22_128, 10, tab.fcb22s_2, 1, 6, tab.cb2232s0, tab.cb2232s1, 11}, { 2, bark_tab_m22_256, 20, tab.fcb22m_2, 2, 6, tab.cb2232m0, tab.cb2232m1, 11}, { 1, bark_tab_l22_512, 32, tab.fcb22l_2, 4, 6, tab.cb2232l0, tab.cb2232l1, 12} }, 512 , 16, tab.lsp22_2, 1, 6, 4, 4, tab.shape22_2, 9, 56, 36, 7, 72 }; static const ModeTab mode_44_40 = { { {16, bark_tab_s44_128, 10, tab.fcb44s , 1, 6, tab.cb4440s0, tab.cb4440s1, 18}, { 4, bark_tab_m44_512, 20, tab.fcb44m , 2, 6, tab.cb4440m0, tab.cb4440m1, 17}, { 1, bark_tab_l44_2048,40, tab.fcb44l , 4, 6, tab.cb4440l0, tab.cb4440l1, 17} }, 2048, 20, tab.lsp44, 1, 6, 4, 4, tab.shape44 , 9, 84, 54, 7, 432 }; static const ModeTab mode_44_48 = { { {16, bark_tab_s44_128, 10, tab.fcb44s , 1, 6, tab.cb4448s0, tab.cb4448s1, 15}, { 4, bark_tab_m44_512, 20, tab.fcb44m , 2, 6, tab.cb4448m0, tab.cb4448m1, 14}, { 1, bark_tab_l44_2048,40, tab.fcb44l , 4, 6, tab.cb4448l0, tab.cb4448l1, 14} }, 2048, 20, tab.lsp44, 1, 6, 4, 4, tab.shape44 , 9, 84, 54, 7, 432 }; typedef struct TwinContext { AVCodecContext *avctx; DSPContext dsp; FFTContext mdct_ctx[3]; const ModeTab *mtab; // history float lsp_hist[2][20]; ///< LSP coefficients of the last frame float bark_hist[3][2][40]; ///< BSE coefficients of last frame // bitstream parameters int16_t permut[4][4096]; uint8_t length[4][2]; ///< main codebook stride uint8_t length_change[4]; uint8_t bits_main_spec[2][4][2]; ///< bits for the main codebook int bits_main_spec_change[4]; int n_div[4]; float *spectrum; float *curr_frame; ///< non-interleaved output float *prev_frame; ///< non-interleaved previous frame int last_block_pos[2]; float *cos_tabs[3]; // scratch buffers float *tmp_buf; } TwinContext; #define PPC_SHAPE_CB_SIZE 64 #define PPC_SHAPE_LEN_MAX 60 #define SUB_AMP_MAX 4500.0 #define MULAW_MU 100.0 #define GAIN_BITS 8 #define AMP_MAX 13000.0 #define SUB_GAIN_BITS 5 #define WINDOW_TYPE_BITS 4 #define PGAIN_MU 200 #define LSP_COEFS_MAX 20 #define LSP_SPLIT_MAX 4 #define CHANNELS_MAX 2 #define SUBBLOCKS_MAX 16 #define BARK_N_COEF_MAX 4 /** @note not speed critical, hence not optimized */ static void memset_float(float *buf, float val, int size) { while (size--) *buf++ = val; } /** * Evaluate a single LPC amplitude spectrum envelope coefficient from the line * spectrum pairs. * * @param lsp a vector of the cosinus of the LSP values * @param cos_val cos(PI*i/N) where i is the index of the LPC amplitude * @param order the order of the LSP (and the size of the *lsp buffer). Must * be a multiple of four. * @return the LPC value * * @todo reuse code from Vorbis decoder: vorbis_floor0_decode */ static float eval_lpc_spectrum(const float *lsp, float cos_val, int order) { int j; float p = 0.5f; float q = 0.5f; float two_cos_w = 2.0f*cos_val; for (j = 0; j + 1 < order; j += 2*2) { // Unroll the loop once since order is a multiple of four q *= lsp[j ] - two_cos_w; p *= lsp[j+1] - two_cos_w; q *= lsp[j+2] - two_cos_w; p *= lsp[j+3] - two_cos_w; } p *= p * (2.0f - two_cos_w); q *= q * (2.0f + two_cos_w); return 0.5 / (p + q); } /** * Evaluate the LPC amplitude spectrum envelope from the line spectrum pairs. */ static void eval_lpcenv(TwinContext *tctx, const float *cos_vals, float *lpc) { int i; const ModeTab *mtab = tctx->mtab; int size_s = mtab->size / mtab->fmode[FT_SHORT].sub; for (i = 0; i < size_s/2; i++) { float cos_i = tctx->cos_tabs[0][i]; lpc[i] = eval_lpc_spectrum(cos_vals, cos_i, mtab->n_lsp); lpc[size_s-i-1] = eval_lpc_spectrum(cos_vals, -cos_i, mtab->n_lsp); } } static void interpolate(float *out, float v1, float v2, int size) { int i; float step = (v1 - v2)/(size + 1); for (i = 0; i < size; i++) { v2 += step; out[i] = v2; } } static inline float get_cos(int idx, int part, const float *cos_tab, int size) { return part ? -cos_tab[size - idx - 1] : cos_tab[ idx ]; } /** * Evaluate the LPC amplitude spectrum envelope from the line spectrum pairs. * Probably for speed reasons, the coefficients are evaluated as * siiiibiiiisiiiibiiiisiiiibiiiisiiiibiiiis ... * where s is an evaluated value, i is a value interpolated from the others * and b might be either calculated or interpolated, depending on an * unexplained condition. * * @param step the size of a block "siiiibiiii" * @param in the cosinus of the LSP data * @param part is 0 for 0...PI (positive cossinus values) and 1 for PI...2PI (negative cossinus values) * @param size the size of the whole output */ static inline void eval_lpcenv_or_interp(TwinContext *tctx, enum FrameType ftype, float *out, const float *in, int size, int step, int part) { int i; const ModeTab *mtab = tctx->mtab; const float *cos_tab = tctx->cos_tabs[ftype]; // Fill the 's' for (i = 0; i < size; i += step) out[i] = eval_lpc_spectrum(in, get_cos(i, part, cos_tab, size), mtab->n_lsp); // Fill the 'iiiibiiii' for (i = step; i <= size - 2*step; i += step) { if (out[i + step] + out[i - step] > 1.95*out[i] || out[i + step] >= out[i - step]) { interpolate(out + i - step + 1, out[i], out[i-step], step - 1); } else { out[i - step/2] = eval_lpc_spectrum(in, get_cos(i-step/2, part, cos_tab, size), mtab->n_lsp); interpolate(out + i - step + 1, out[i-step/2], out[i-step ], step/2 - 1); interpolate(out + i - step/2 + 1, out[i ], out[i-step/2], step/2 - 1); } } interpolate(out + size - 2*step + 1, out[size-step], out[size - 2*step], step - 1); } static void eval_lpcenv_2parts(TwinContext *tctx, enum FrameType ftype, const float *buf, float *lpc, int size, int step) { eval_lpcenv_or_interp(tctx, ftype, lpc , buf, size/2, step, 0); eval_lpcenv_or_interp(tctx, ftype, lpc + size/2, buf, size/2, 2*step, 1); interpolate(lpc+size/2-step+1, lpc[size/2], lpc[size/2-step], step); memset_float(lpc + size - 2*step + 1, lpc[size - 2*step], 2*step - 1); } /** * Inverse quantization. Read CB coefficients for cb1 and cb2 from the * bitstream, sum the corresponding vectors and write the result to *out * after permutation. */ static void dequant(TwinContext *tctx, GetBitContext *gb, float *out, enum FrameType ftype, const int16_t *cb0, const int16_t *cb1, int cb_len) { int pos = 0; int i, j; for (i = 0; i < tctx->n_div[ftype]; i++) { int tmp0, tmp1; int sign0 = 1; int sign1 = 1; const int16_t *tab0, *tab1; int length = tctx->length[ftype][i >= tctx->length_change[ftype]]; int bitstream_second_part = (i >= tctx->bits_main_spec_change[ftype]); int bits = tctx->bits_main_spec[0][ftype][bitstream_second_part]; if (bits == 7) { if (get_bits1(gb)) sign0 = -1; bits = 6; } tmp0 = get_bits(gb, bits); bits = tctx->bits_main_spec[1][ftype][bitstream_second_part]; if (bits == 7) { if (get_bits1(gb)) sign1 = -1; bits = 6; } tmp1 = get_bits(gb, bits); tab0 = cb0 + tmp0*cb_len; tab1 = cb1 + tmp1*cb_len; for (j = 0; j < length; j++) out[tctx->permut[ftype][pos+j]] = sign0*tab0[j] + sign1*tab1[j]; pos += length; } } static inline float mulawinv(float y, float clip, float mu) { y = av_clipf(y/clip, -1, 1); return clip * FFSIGN(y) * (exp(log(1+mu) * fabs(y)) - 1) / mu; } /** * Evaluate a*b/400 rounded to the nearest integer. When, for example, * a*b == 200 and the nearest integer is ill-defined, use a table to emulate * the following broken float-based implementation used by the binary decoder: * * @code * static int very_broken_op(int a, int b) * { * static float test; // Ugh, force gcc to do the division first... * * test = a/400.; * return b * test + 0.5; * } * @endcode * * @note if this function is replaced by just ROUNDED_DIV(a*b,400.), the stddev * between the original file (before encoding with Yamaha encoder) and the * decoded output increases, which leads one to believe that the encoder expects * exactly this broken calculation. */ static int very_broken_op(int a, int b) { int x = a*b + 200; int size; const uint8_t *rtab; if (x%400 || b%5) return x/400; x /= 400; size = tabs[b/5].size; rtab = tabs[b/5].tab; return x - rtab[size*av_log2(2*(x - 1)/size)+(x - 1)%size]; } /** * Sum to data a periodic peak of a given period, width and shape. * * @param period the period of the peak divised by 400.0 */ static void add_peak(int period, int width, const float *shape, float ppc_gain, float *speech, int len) { int i, j; const float *shape_end = shape + len; int center; // First peak centered around zero for (i = 0; i < width/2; i++) speech[i] += ppc_gain * *shape++; for (i = 1; i < ROUNDED_DIV(len,width) ; i++) { center = very_broken_op(period, i); for (j = -width/2; j < (width+1)/2; j++) speech[j+center] += ppc_gain * *shape++; } // For the last block, be careful not to go beyond the end of the buffer center = very_broken_op(period, i); for (j = -width/2; j < (width + 1)/2 && shape < shape_end; j++) speech[j+center] += ppc_gain * *shape++; } static void decode_ppc(TwinContext *tctx, int period_coef, const float *shape, float ppc_gain, float *speech) { const ModeTab *mtab = tctx->mtab; int isampf = tctx->avctx->sample_rate/1000; int ibps = tctx->avctx->bit_rate/(1000 * tctx->avctx->channels); int min_period = ROUNDED_DIV( 40*2*mtab->size, isampf); int max_period = ROUNDED_DIV(6*40*2*mtab->size, isampf); int period_range = max_period - min_period; // This is actually the period multiplied by 400. It is just linearly coded // between its maximum and minimum value. int period = min_period + ROUNDED_DIV(period_coef*period_range, (1 << mtab->ppc_period_bit) - 1); int width; if (isampf == 22 && ibps == 32) { // For some unknown reason, NTT decided to code this case differently... width = ROUNDED_DIV((period + 800)* mtab->peak_per2wid, 400*mtab->size); } else width = (period )* mtab->peak_per2wid/(400*mtab->size); add_peak(period, width, shape, ppc_gain, speech, mtab->ppc_shape_len); } static void dec_gain(TwinContext *tctx, GetBitContext *gb, enum FrameType ftype, float *out) { const ModeTab *mtab = tctx->mtab; int i, j; int sub = mtab->fmode[ftype].sub; float step = AMP_MAX / ((1 << GAIN_BITS) - 1); float sub_step = SUB_AMP_MAX / ((1 << SUB_GAIN_BITS) - 1); if (ftype == FT_LONG) { for (i = 0; i < tctx->avctx->channels; i++) out[i] = (1./(1<<13)) * mulawinv(step * 0.5 + step * get_bits(gb, GAIN_BITS), AMP_MAX, MULAW_MU); } else { for (i = 0; i < tctx->avctx->channels; i++) { float val = (1./(1<<23)) * mulawinv(step * 0.5 + step * get_bits(gb, GAIN_BITS), AMP_MAX, MULAW_MU); for (j = 0; j < sub; j++) { out[i*sub + j] = val*mulawinv(sub_step* 0.5 + sub_step* get_bits(gb, SUB_GAIN_BITS), SUB_AMP_MAX, MULAW_MU); } } } } /** * Rearrange the LSP coefficients so that they have a minimum distance of * min_dist. This function does it exactly as described in section of 3.2.4 * of the G.729 specification (but interestingly is different from what the * reference decoder actually does). */ static void rearrange_lsp(int order, float *lsp, float min_dist) { int i; float min_dist2 = min_dist * 0.5; for (i = 1; i < order; i++) if (lsp[i] - lsp[i-1] < min_dist) { float avg = (lsp[i] + lsp[i-1]) * 0.5; lsp[i-1] = avg - min_dist2; lsp[i ] = avg + min_dist2; } } static void decode_lsp(TwinContext *tctx, int lpc_idx1, uint8_t *lpc_idx2, int lpc_hist_idx, float *lsp, float *hist) { const ModeTab *mtab = tctx->mtab; int i, j; const float *cb = mtab->lspcodebook; const float *cb2 = cb + (1 << mtab->lsp_bit1)*mtab->n_lsp; const float *cb3 = cb2 + (1 << mtab->lsp_bit2)*mtab->n_lsp; const int8_t funny_rounding[4] = { -2, mtab->lsp_split == 4 ? -2 : 1, mtab->lsp_split == 4 ? -2 : 1, 0 }; j = 0; for (i = 0; i < mtab->lsp_split; i++) { int chunk_end = ((i + 1)*mtab->n_lsp + funny_rounding[i])/mtab->lsp_split; for (; j < chunk_end; j++) lsp[j] = cb [lpc_idx1 * mtab->n_lsp + j] + cb2[lpc_idx2[i] * mtab->n_lsp + j]; } rearrange_lsp(mtab->n_lsp, lsp, 0.0001); for (i = 0; i < mtab->n_lsp; i++) { float tmp1 = 1. - cb3[lpc_hist_idx*mtab->n_lsp + i]; float tmp2 = hist[i] * cb3[lpc_hist_idx*mtab->n_lsp + i]; hist[i] = lsp[i]; lsp[i] = lsp[i] * tmp1 + tmp2; } rearrange_lsp(mtab->n_lsp, lsp, 0.0001); rearrange_lsp(mtab->n_lsp, lsp, 0.000095); ff_sort_nearly_sorted_floats(lsp, mtab->n_lsp); } static void dec_lpc_spectrum_inv(TwinContext *tctx, float *lsp, enum FrameType ftype, float *lpc) { int i; int size = tctx->mtab->size / tctx->mtab->fmode[ftype].sub; for (i = 0; i < tctx->mtab->n_lsp; i++) lsp[i] = 2*cos(lsp[i]); switch (ftype) { case FT_LONG: eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 8); break; case FT_MEDIUM: eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 2); break; case FT_SHORT: eval_lpcenv(tctx, lsp, lpc); break; } } static void imdct_and_window(TwinContext *tctx, enum FrameType ftype, int wtype, float *in, float *prev, int ch) { FFTContext *mdct = &tctx->mdct_ctx[ftype]; const ModeTab *mtab = tctx->mtab; int bsize = mtab->size / mtab->fmode[ftype].sub; int size = mtab->size; float *buf1 = tctx->tmp_buf; int j; int wsize; // Window size float *out = tctx->curr_frame + 2*ch*mtab->size; float *out2 = out; float *prev_buf; int first_wsize; static const uint8_t wtype_to_wsize[] = {0, 0, 2, 2, 2, 1, 0, 1, 1}; int types_sizes[] = { mtab->size / mtab->fmode[FT_LONG ].sub, mtab->size / mtab->fmode[FT_MEDIUM].sub, mtab->size / (2*mtab->fmode[FT_SHORT ].sub), }; wsize = types_sizes[wtype_to_wsize[wtype]]; first_wsize = wsize; prev_buf = prev + (size - bsize)/2; for (j = 0; j < mtab->fmode[ftype].sub; j++) { int sub_wtype = ftype == FT_MEDIUM ? 8 : wtype; if (!j && wtype == 4) sub_wtype = 4; else if (j == mtab->fmode[ftype].sub-1 && wtype == 7) sub_wtype = 7; wsize = types_sizes[wtype_to_wsize[sub_wtype]]; mdct->imdct_half(mdct, buf1 + bsize*j, in + bsize*j); tctx->dsp.vector_fmul_window(out2, prev_buf + (bsize-wsize)/2, buf1 + bsize*j, ff_sine_windows[av_log2(wsize)], wsize/2); out2 += wsize; memcpy(out2, buf1 + bsize*j + wsize/2, (bsize - wsize/2)*sizeof(float)); out2 += ftype == FT_MEDIUM ? (bsize-wsize)/2 : bsize - wsize; prev_buf = buf1 + bsize*j + bsize/2; } tctx->last_block_pos[ch] = (size + first_wsize)/2; } static void imdct_output(TwinContext *tctx, enum FrameType ftype, int wtype, float *out) { const ModeTab *mtab = tctx->mtab; float *prev_buf = tctx->prev_frame + tctx->last_block_pos[0]; int i, j; for (i = 0; i < tctx->avctx->channels; i++) { imdct_and_window(tctx, ftype, wtype, tctx->spectrum + i*mtab->size, prev_buf + 2*i*mtab->size, i); } if (tctx->avctx->channels == 2) { for (i = 0; i < mtab->size - tctx->last_block_pos[0]; i++) { float f1 = prev_buf[ i]; float f2 = prev_buf[2*mtab->size + i]; out[2*i ] = f1 + f2; out[2*i + 1] = f1 - f2; } for (j = 0; i < mtab->size; j++,i++) { float f1 = tctx->curr_frame[ j]; float f2 = tctx->curr_frame[2*mtab->size + j]; out[2*i ] = f1 + f2; out[2*i + 1] = f1 - f2; } } else { memcpy(out, prev_buf, (mtab->size - tctx->last_block_pos[0]) * sizeof(*out)); out += mtab->size - tctx->last_block_pos[0]; memcpy(out, tctx->curr_frame, (tctx->last_block_pos[0]) * sizeof(*out)); } } static void dec_bark_env(TwinContext *tctx, const uint8_t *in, int use_hist, int ch, float *out, float gain, enum FrameType ftype) { const ModeTab *mtab = tctx->mtab; int i,j; float *hist = tctx->bark_hist[ftype][ch]; float val = ((const float []) {0.4, 0.35, 0.28})[ftype]; int bark_n_coef = mtab->fmode[ftype].bark_n_coef; int fw_cb_len = mtab->fmode[ftype].bark_env_size / bark_n_coef; int idx = 0; for (i = 0; i < fw_cb_len; i++) for (j = 0; j < bark_n_coef; j++, idx++) { float tmp2 = mtab->fmode[ftype].bark_cb[fw_cb_len*in[j] + i] * (1./4096); float st = use_hist ? (1. - val) * tmp2 + val*hist[idx] + 1. : tmp2 + 1.; hist[idx] = tmp2; if (st < -1.) st = 1.; memset_float(out, st * gain, mtab->fmode[ftype].bark_tab[idx]); out += mtab->fmode[ftype].bark_tab[idx]; } } static void read_and_decode_spectrum(TwinContext *tctx, GetBitContext *gb, float *out, enum FrameType ftype) { const ModeTab *mtab = tctx->mtab; int channels = tctx->avctx->channels; int sub = mtab->fmode[ftype].sub; int block_size = mtab->size / sub; float gain[CHANNELS_MAX*SUBBLOCKS_MAX]; float ppc_shape[PPC_SHAPE_LEN_MAX * CHANNELS_MAX * 4]; uint8_t bark1[CHANNELS_MAX][SUBBLOCKS_MAX][BARK_N_COEF_MAX]; uint8_t bark_use_hist[CHANNELS_MAX][SUBBLOCKS_MAX]; uint8_t lpc_idx1[CHANNELS_MAX]; uint8_t lpc_idx2[CHANNELS_MAX][LSP_SPLIT_MAX]; uint8_t lpc_hist_idx[CHANNELS_MAX]; int i, j, k; dequant(tctx, gb, out, ftype, mtab->fmode[ftype].cb0, mtab->fmode[ftype].cb1, mtab->fmode[ftype].cb_len_read); for (i = 0; i < channels; i++) for (j = 0; j < sub; j++) for (k = 0; k < mtab->fmode[ftype].bark_n_coef; k++) bark1[i][j][k] = get_bits(gb, mtab->fmode[ftype].bark_n_bit); for (i = 0; i < channels; i++) for (j = 0; j < sub; j++) bark_use_hist[i][j] = get_bits1(gb); dec_gain(tctx, gb, ftype, gain); for (i = 0; i < channels; i++) { lpc_hist_idx[i] = get_bits(gb, tctx->mtab->lsp_bit0); lpc_idx1 [i] = get_bits(gb, tctx->mtab->lsp_bit1); for (j = 0; j < tctx->mtab->lsp_split; j++) lpc_idx2[i][j] = get_bits(gb, tctx->mtab->lsp_bit2); } if (ftype == FT_LONG) { int cb_len_p = (tctx->n_div[3] + mtab->ppc_shape_len*channels - 1)/ tctx->n_div[3]; dequant(tctx, gb, ppc_shape, FT_PPC, mtab->ppc_shape_cb, mtab->ppc_shape_cb + cb_len_p*PPC_SHAPE_CB_SIZE, cb_len_p); } for (i = 0; i < channels; i++) { float *chunk = out + mtab->size * i; float lsp[LSP_COEFS_MAX]; for (j = 0; j < sub; j++) { dec_bark_env(tctx, bark1[i][j], bark_use_hist[i][j], i, tctx->tmp_buf, gain[sub*i+j], ftype); tctx->dsp.vector_fmul(chunk + block_size*j, chunk + block_size*j, tctx->tmp_buf, block_size); } if (ftype == FT_LONG) { float pgain_step = 25000. / ((1 << mtab->pgain_bit) - 1); int p_coef = get_bits(gb, tctx->mtab->ppc_period_bit); int g_coef = get_bits(gb, tctx->mtab->pgain_bit); float v = 1./8192* mulawinv(pgain_step*g_coef+ pgain_step/2, 25000., PGAIN_MU); decode_ppc(tctx, p_coef, ppc_shape + i*mtab->ppc_shape_len, v, chunk); } decode_lsp(tctx, lpc_idx1[i], lpc_idx2[i], lpc_hist_idx[i], lsp, tctx->lsp_hist[i]); dec_lpc_spectrum_inv(tctx, lsp, ftype, tctx->tmp_buf); for (j = 0; j < mtab->fmode[ftype].sub; j++) { tctx->dsp.vector_fmul(chunk, chunk, tctx->tmp_buf, block_size); chunk += block_size; } } } static int twin_decode_frame(AVCodecContext * avctx, void *data, int *data_size, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; TwinContext *tctx = avctx->priv_data; GetBitContext gb; const ModeTab *mtab = tctx->mtab; float *out = data; enum FrameType ftype; int window_type, out_size; static const enum FrameType wtype_to_ftype_table[] = { FT_LONG, FT_LONG, FT_SHORT, FT_LONG, FT_MEDIUM, FT_LONG, FT_LONG, FT_MEDIUM, FT_MEDIUM }; if (buf_size*8 < avctx->bit_rate*mtab->size/avctx->sample_rate + 8) { av_log(avctx, AV_LOG_ERROR, "Frame too small (%d bytes). Truncated file?\n", buf_size); return AVERROR(EINVAL); } out_size = mtab->size * avctx->channels * av_get_bytes_per_sample(avctx->sample_fmt); if (*data_size < out_size) { av_log(avctx, AV_LOG_ERROR, "output buffer is too small\n"); return AVERROR(EINVAL); } init_get_bits(&gb, buf, buf_size * 8); skip_bits(&gb, get_bits(&gb, 8)); window_type = get_bits(&gb, WINDOW_TYPE_BITS); if (window_type > 8) { av_log(avctx, AV_LOG_ERROR, "Invalid window type, broken sample?\n"); return -1; } ftype = wtype_to_ftype_table[window_type]; read_and_decode_spectrum(tctx, &gb, tctx->spectrum, ftype); imdct_output(tctx, ftype, window_type, out); FFSWAP(float*, tctx->curr_frame, tctx->prev_frame); if (tctx->avctx->frame_number < 2) { *data_size=0; return buf_size; } *data_size = out_size; return buf_size; } /** * Init IMDCT and windowing tables */ static av_cold void init_mdct_win(TwinContext *tctx) { int i,j; const ModeTab *mtab = tctx->mtab; int size_s = mtab->size / mtab->fmode[FT_SHORT].sub; int size_m = mtab->size / mtab->fmode[FT_MEDIUM].sub; int channels = tctx->avctx->channels; float norm = channels == 1 ? 2. : 1.; for (i = 0; i < 3; i++) { int bsize = tctx->mtab->size/tctx->mtab->fmode[i].sub; ff_mdct_init(&tctx->mdct_ctx[i], av_log2(bsize) + 1, 1, -sqrt(norm/bsize) / (1<<15)); } tctx->tmp_buf = av_malloc(mtab->size * sizeof(*tctx->tmp_buf)); tctx->spectrum = av_malloc(2*mtab->size*channels*sizeof(float)); tctx->curr_frame = av_malloc(2*mtab->size*channels*sizeof(float)); tctx->prev_frame = av_malloc(2*mtab->size*channels*sizeof(float)); for (i = 0; i < 3; i++) { int m = 4*mtab->size/mtab->fmode[i].sub; double freq = 2*M_PI/m; tctx->cos_tabs[i] = av_malloc((m/4)*sizeof(*tctx->cos_tabs)); for (j = 0; j <= m/8; j++) tctx->cos_tabs[i][j] = cos((2*j + 1)*freq); for (j = 1; j < m/8; j++) tctx->cos_tabs[i][m/4-j] = tctx->cos_tabs[i][j]; } ff_init_ff_sine_windows(av_log2(size_m)); ff_init_ff_sine_windows(av_log2(size_s/2)); ff_init_ff_sine_windows(av_log2(mtab->size)); } /** * Interpret the data as if it were a num_blocks x line_len[0] matrix and for * each line do a cyclic permutation, i.e. * abcdefghijklm -> defghijklmabc * where the amount to be shifted is evaluated depending on the column. */ static void permutate_in_line(int16_t *tab, int num_vect, int num_blocks, int block_size, const uint8_t line_len[2], int length_div, enum FrameType ftype) { int i,j; for (i = 0; i < line_len[0]; i++) { int shift; if (num_blocks == 1 || (ftype == FT_LONG && num_vect % num_blocks) || (ftype != FT_LONG && num_vect & 1 ) || i == line_len[1]) { shift = 0; } else if (ftype == FT_LONG) { shift = i; } else shift = i*i; for (j = 0; j < num_vect && (j+num_vect*i < block_size*num_blocks); j++) tab[i*num_vect+j] = i*num_vect + (j + shift) % num_vect; } } /** * Interpret the input data as in the following table: * * @verbatim * * abcdefgh * ijklmnop * qrstuvw * x123456 * * @endverbatim * * and transpose it, giving the output * aiqxbjr1cks2dlt3emu4fvn5gow6hp */ static void transpose_perm(int16_t *out, int16_t *in, int num_vect, const uint8_t line_len[2], int length_div) { int i,j; int cont= 0; for (i = 0; i < num_vect; i++) for (j = 0; j < line_len[i >= length_div]; j++) out[cont++] = in[j*num_vect + i]; } static void linear_perm(int16_t *out, int16_t *in, int n_blocks, int size) { int block_size = size/n_blocks; int i; for (i = 0; i < size; i++) out[i] = block_size * (in[i] % n_blocks) + in[i] / n_blocks; } static av_cold void construct_perm_table(TwinContext *tctx,enum FrameType ftype) { int block_size; const ModeTab *mtab = tctx->mtab; int size = tctx->avctx->channels*mtab->fmode[ftype].sub; int16_t *tmp_perm = (int16_t *) tctx->tmp_buf; if (ftype == FT_PPC) { size = tctx->avctx->channels; block_size = mtab->ppc_shape_len; } else block_size = mtab->size / mtab->fmode[ftype].sub; permutate_in_line(tmp_perm, tctx->n_div[ftype], size, block_size, tctx->length[ftype], tctx->length_change[ftype], ftype); transpose_perm(tctx->permut[ftype], tmp_perm, tctx->n_div[ftype], tctx->length[ftype], tctx->length_change[ftype]); linear_perm(tctx->permut[ftype], tctx->permut[ftype], size, size*block_size); } static av_cold void init_bitstream_params(TwinContext *tctx) { const ModeTab *mtab = tctx->mtab; int n_ch = tctx->avctx->channels; int total_fr_bits = tctx->avctx->bit_rate*mtab->size/ tctx->avctx->sample_rate; int lsp_bits_per_block = n_ch*(mtab->lsp_bit0 + mtab->lsp_bit1 + mtab->lsp_split*mtab->lsp_bit2); int ppc_bits = n_ch*(mtab->pgain_bit + mtab->ppc_shape_bit + mtab->ppc_period_bit); int bsize_no_main_cb[3]; int bse_bits[3]; int i; enum FrameType frametype; for (i = 0; i < 3; i++) // +1 for history usage switch bse_bits[i] = n_ch * (mtab->fmode[i].bark_n_coef * mtab->fmode[i].bark_n_bit + 1); bsize_no_main_cb[2] = bse_bits[2] + lsp_bits_per_block + ppc_bits + WINDOW_TYPE_BITS + n_ch*GAIN_BITS; for (i = 0; i < 2; i++) bsize_no_main_cb[i] = lsp_bits_per_block + n_ch*GAIN_BITS + WINDOW_TYPE_BITS + mtab->fmode[i].sub*(bse_bits[i] + n_ch*SUB_GAIN_BITS); // The remaining bits are all used for the main spectrum coefficients for (i = 0; i < 4; i++) { int bit_size; int vect_size; int rounded_up, rounded_down, num_rounded_down, num_rounded_up; if (i == 3) { bit_size = n_ch * mtab->ppc_shape_bit; vect_size = n_ch * mtab->ppc_shape_len; } else { bit_size = total_fr_bits - bsize_no_main_cb[i]; vect_size = n_ch * mtab->size; } tctx->n_div[i] = (bit_size + 13) / 14; rounded_up = (bit_size + tctx->n_div[i] - 1)/tctx->n_div[i]; rounded_down = (bit_size )/tctx->n_div[i]; num_rounded_down = rounded_up * tctx->n_div[i] - bit_size; num_rounded_up = tctx->n_div[i] - num_rounded_down; tctx->bits_main_spec[0][i][0] = (rounded_up + 1)/2; tctx->bits_main_spec[1][i][0] = (rounded_up )/2; tctx->bits_main_spec[0][i][1] = (rounded_down + 1)/2; tctx->bits_main_spec[1][i][1] = (rounded_down )/2; tctx->bits_main_spec_change[i] = num_rounded_up; rounded_up = (vect_size + tctx->n_div[i] - 1)/tctx->n_div[i]; rounded_down = (vect_size )/tctx->n_div[i]; num_rounded_down = rounded_up * tctx->n_div[i] - vect_size; num_rounded_up = tctx->n_div[i] - num_rounded_down; tctx->length[i][0] = rounded_up; tctx->length[i][1] = rounded_down; tctx->length_change[i] = num_rounded_up; } for (frametype = FT_SHORT; frametype <= FT_PPC; frametype++) construct_perm_table(tctx, frametype); } static av_cold int twin_decode_init(AVCodecContext *avctx) { TwinContext *tctx = avctx->priv_data; int isampf = avctx->sample_rate/1000; int ibps = avctx->bit_rate/(1000 * avctx->channels); tctx->avctx = avctx; avctx->sample_fmt = AV_SAMPLE_FMT_FLT; if (avctx->channels > CHANNELS_MAX) { av_log(avctx, AV_LOG_ERROR, "Unsupported number of channels: %i\n", avctx->channels); return -1; } switch ((isampf << 8) + ibps) { case (8 <<8) + 8: tctx->mtab = &mode_08_08; break; case (11<<8) + 8: tctx->mtab = &mode_11_08; break; case (11<<8) + 10: tctx->mtab = &mode_11_10; break; case (16<<8) + 16: tctx->mtab = &mode_16_16; break; case (22<<8) + 20: tctx->mtab = &mode_22_20; break; case (22<<8) + 24: tctx->mtab = &mode_22_24; break; case (22<<8) + 32: tctx->mtab = &mode_22_32; break; case (44<<8) + 40: tctx->mtab = &mode_44_40; break; case (44<<8) + 48: tctx->mtab = &mode_44_48; break; default: av_log(avctx, AV_LOG_ERROR, "This version does not support %d kHz - %d kbit/s/ch mode.\n", isampf, isampf); return -1; } dsputil_init(&tctx->dsp, avctx); init_mdct_win(tctx); init_bitstream_params(tctx); memset_float(tctx->bark_hist[0][0], 0.1, FF_ARRAY_ELEMS(tctx->bark_hist)); return 0; } static av_cold int twin_decode_close(AVCodecContext *avctx) { TwinContext *tctx = avctx->priv_data; int i; for (i = 0; i < 3; i++) { ff_mdct_end(&tctx->mdct_ctx[i]); av_free(tctx->cos_tabs[i]); } av_free(tctx->curr_frame); av_free(tctx->spectrum); av_free(tctx->prev_frame); av_free(tctx->tmp_buf); return 0; } AVCodec ff_twinvq_decoder = { .name = "twinvq", .type = AVMEDIA_TYPE_AUDIO, .id = CODEC_ID_TWINVQ, .priv_data_size = sizeof(TwinContext), .init = twin_decode_init, .close = twin_decode_close, .decode = twin_decode_frame, .long_name = NULL_IF_CONFIG_SMALL("VQF TwinVQ"), };