static int wma_decode_init(AVCodecContext * avctx) { WMADecodeContext *s = avctx->priv_data; int i, flags1, flags2; float *window; uint8_t *extradata; float bps1, high_freq; volatile float bps; int sample_rate1; int coef_vlc_table; s->sample_rate = avctx->sample_rate; s->nb_channels = avctx->channels; s->bit_rate = avctx->bit_rate; s->block_align = avctx->block_align; if (avctx->codec->id == CODEC_ID_WMAV1) { s->version = 1; } else { s->version = 2; } /* extract flag infos */ flags1 = 0; flags2 = 0; extradata = avctx->extradata; if (s->version == 1 && avctx->extradata_size >= 4) { flags1 = extradata[0] | (extradata[1] << 8); flags2 = extradata[2] | (extradata[3] << 8); } else if (s->version == 2 && avctx->extradata_size >= 6) { flags1 = extradata[0] | (extradata[1] << 8) | (extradata[2] << 16) | (extradata[3] << 24); flags2 = extradata[4] | (extradata[5] << 8); } s->use_exp_vlc = flags2 & 0x0001; s->use_bit_reservoir = flags2 & 0x0002; s->use_variable_block_len = flags2 & 0x0004; /* compute MDCT block size */ if (s->sample_rate <= 16000) { s->frame_len_bits = 9; } else if (s->sample_rate <= 22050 || (s->sample_rate <= 32000 && s->version == 1)) { s->frame_len_bits = 10; } else { s->frame_len_bits = 11; } s->frame_len = 1 << s->frame_len_bits; if (s->use_variable_block_len) { int nb_max, nb; nb = ((flags2 >> 3) & 3) + 1; if ((s->bit_rate / s->nb_channels) >= 32000) nb += 2; nb_max = s->frame_len_bits - BLOCK_MIN_BITS; if (nb > nb_max) nb = nb_max; s->nb_block_sizes = nb + 1; } else { s->nb_block_sizes = 1; } /* init rate dependant parameters */ s->use_noise_coding = 1; high_freq = s->sample_rate * 0.5; /* if version 2, then the rates are normalized */ sample_rate1 = s->sample_rate; if (s->version == 2) { if (sample_rate1 >= 44100) sample_rate1 = 44100; else if (sample_rate1 >= 22050) sample_rate1 = 22050; else if (sample_rate1 >= 16000) sample_rate1 = 16000; else if (sample_rate1 >= 11025) sample_rate1 = 11025; else if (sample_rate1 >= 8000) sample_rate1 = 8000; } bps = (float)s->bit_rate / (float)(s->nb_channels * s->sample_rate); s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0)) + 2; /* compute high frequency value and choose if noise coding should be activated */ bps1 = bps; if (s->nb_channels == 2) bps1 = bps * 1.6; if (sample_rate1 == 44100) { if (bps1 >= 0.61) s->use_noise_coding = 0; else high_freq = high_freq * 0.4; } else if (sample_rate1 == 22050) { if (bps1 >= 1.16) s->use_noise_coding = 0; else if (bps1 >= 0.72) high_freq = high_freq * 0.7; else high_freq = high_freq * 0.6; } else if (sample_rate1 == 16000) { if (bps > 0.5) high_freq = high_freq * 0.5; else high_freq = high_freq * 0.3; } else if (sample_rate1 == 11025) { high_freq = high_freq * 0.7; } else if (sample_rate1 == 8000) { if (bps <= 0.625) { high_freq = high_freq * 0.5; } else if (bps > 0.75) { s->use_noise_coding = 0; } else { high_freq = high_freq * 0.65; } } else { if (bps >= 0.8) { high_freq = high_freq * 0.75; } else if (bps >= 0.6) { high_freq = high_freq * 0.6; } else { high_freq = high_freq * 0.5; } } dprintf("flags1=0x%x flags2=0x%x\n", flags1, flags2); dprintf("version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n", s->version, s->nb_channels, s->sample_rate, s->bit_rate, s->block_align); dprintf("bps=%f bps1=%f high_freq=%f bitoffset=%d\n", bps, bps1, high_freq, s->byte_offset_bits); dprintf("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n", s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes); /* compute the scale factor band sizes for each MDCT block size */ { int a, b, pos, lpos, k, block_len, i, j, n; const uint8_t *table; if (s->version == 1) { s->coefs_start = 3; } else { s->coefs_start = 0; } for(k = 0; k < s->nb_block_sizes; k++) { block_len = s->frame_len >> k; if (s->version == 1) { lpos = 0; for(i=0;i<25;i++) { a = wma_critical_freqs[i]; b = s->sample_rate; pos = ((block_len * 2 * a) + (b >> 1)) / b; if (pos > block_len) pos = block_len; s->exponent_bands[0][i] = pos - lpos; if (pos >= block_len) { i++; break; } lpos = pos; } s->exponent_sizes[0] = i; } else { /* hardcoded tables */ table = NULL; a = s->frame_len_bits - BLOCK_MIN_BITS - k; if (a < 3) { if (s->sample_rate >= 44100) table = exponent_band_44100[a]; else if (s->sample_rate >= 32000) table = exponent_band_32000[a]; else if (s->sample_rate >= 22050) table = exponent_band_22050[a]; } if (table) { n = *table++; for(i=0;i<n;i++) s->exponent_bands[k][i] = table[i]; s->exponent_sizes[k] = n; } else { j = 0; lpos = 0; for(i=0;i<25;i++) { a = wma_critical_freqs[i]; b = s->sample_rate; pos = ((block_len * 2 * a) + (b << 1)) / (4 * b); pos <<= 2; if (pos > block_len) pos = block_len; if (pos > lpos) s->exponent_bands[k][j++] = pos - lpos; if (pos >= block_len) break; lpos = pos; } s->exponent_sizes[k] = j; } } /* max number of coefs */ s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k; /* high freq computation */ s->high_band_start[k] = (int)((block_len * 2 * high_freq) / s->sample_rate + 0.5); n = s->exponent_sizes[k]; j = 0; pos = 0; for(i=0;i<n;i++) { int start, end; start = pos; pos += s->exponent_bands[k][i]; end = pos; if (start < s->high_band_start[k]) start = s->high_band_start[k]; if (end > s->coefs_end[k]) end = s->coefs_end[k]; if (end > start) s->exponent_high_bands[k][j++] = end - start; } s->exponent_high_sizes[k] = j; #if 0 tprintf("%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ", s->frame_len >> k, s->coefs_end[k], s->high_band_start[k], s->exponent_high_sizes[k]); for(j=0;j<s->exponent_high_sizes[k];j++) tprintf(" %d", s->exponent_high_bands[k][j]); tprintf("\n"); #endif } } #ifdef TRACE { int i, j; for(i = 0; i < s->nb_block_sizes; i++) { tprintf("%5d: n=%2d:", s->frame_len >> i, s->exponent_sizes[i]); for(j=0;j<s->exponent_sizes[i];j++) tprintf(" %d", s->exponent_bands[i][j]); tprintf("\n"); } } #endif /* init MDCT */ for(i = 0; i < s->nb_block_sizes; i++) ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1); /* init MDCT windows : simple sinus window */ for(i = 0; i < s->nb_block_sizes; i++) { int n, j; float alpha; n = 1 << (s->frame_len_bits - i); window = av_malloc(sizeof(float) * n); alpha = M_PI / (2.0 * n); for(j=0;j<n;j++) { window[n - j - 1] = sin((j + 0.5) * alpha); } s->windows[i] = window; } s->reset_block_lengths = 1; if (s->use_noise_coding) { /* init the noise generator */ if (s->use_exp_vlc) s->noise_mult = 0.02; else s->noise_mult = 0.04; #ifdef TRACE for(i=0;i<NOISE_TAB_SIZE;i++) s->noise_table[i] = 1.0 * s->noise_mult; #else { unsigned int seed; float norm; seed = 1; norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult; for(i=0;i<NOISE_TAB_SIZE;i++) { seed = seed * 314159 + 1; s->noise_table[i] = (float)((int)seed) * norm; } } #endif init_vlc(&s->hgain_vlc, 9, sizeof(hgain_huffbits), hgain_huffbits, 1, 1, hgain_huffcodes, 2, 2); } if (s->use_exp_vlc) { init_vlc(&s->exp_vlc, 9, sizeof(scale_huffbits), scale_huffbits, 1, 1, scale_huffcodes, 4, 4); } else { wma_lsp_to_curve_init(s, s->frame_len); } /* choose the VLC tables for the coefficients */ coef_vlc_table = 2; if (s->sample_rate >= 32000) { if (bps1 < 0.72) coef_vlc_table = 0; else if (bps1 < 1.16) coef_vlc_table = 1; } init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0], &coef_vlcs[coef_vlc_table * 2]); init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1], &coef_vlcs[coef_vlc_table * 2 + 1]); return 0; }
static int wma_decode_init(AVCodecContext * avctx) { WMADecodeContext *s = avctx->priv_data; int i, flags1, flags2; float *window; uint8_t *extradata; float bps1, high_freq; volatile float bps; int sample_rate1; int coef_vlc_table; s->sample_rate = avctx->sample_rate; s->nb_channels = avctx->channels; s->bit_rate = avctx->bit_rate; s->block_align = avctx->block_align; if (avctx->codec->id == CODEC_ID_WMAV1) { s->version = 1; } else { s->version = 2; }   flags1 = 0; flags2 = 0; extradata = avctx->extradata; if (s->version == 1 && avctx->extradata_size >= 4) { flags1 = extradata[0] | (extradata[1] << 8); flags2 = extradata[2] | (extradata[3] << 8); } else if (s->version == 2 && avctx->extradata_size >= 6) { flags1 = extradata[0] | (extradata[1] << 8) | (extradata[2] << 16) | (extradata[3] << 24); flags2 = extradata[4] | (extradata[5] << 8); } s->use_exp_vlc = flags2 & 0x0001; s->use_bit_reservoir = flags2 & 0x0002; s->use_variable_block_len = flags2 & 0x0004;   if (s->sample_rate <= 16000) { s->frame_len_bits = 9; } else if (s->sample_rate <= 22050 || (s->sample_rate <= 32000 && s->version == 1)) { s->frame_len_bits = 10; } else { s->frame_len_bits = 11; } s->frame_len = 1 << s->frame_len_bits; if (s->use_variable_block_len) { int nb_max, nb; nb = ((flags2 >> 3) & 3) + 1; if ((s->bit_rate / s->nb_channels) >= 32000) nb += 2; nb_max = s->frame_len_bits - BLOCK_MIN_BITS; if (nb > nb_max) nb = nb_max; s->nb_block_sizes = nb + 1; } else { s->nb_block_sizes = 1; }   s->use_noise_coding = 1; high_freq = s->sample_rate * 0.5;   sample_rate1 = s->sample_rate; if (s->version == 2) { if (sample_rate1 >= 44100) sample_rate1 = 44100; else if (sample_rate1 >= 22050) sample_rate1 = 22050; else if (sample_rate1 >= 16000) sample_rate1 = 16000; else if (sample_rate1 >= 11025) sample_rate1 = 11025; else if (sample_rate1 >= 8000) sample_rate1 = 8000; } bps = (float)s->bit_rate / (float)(s->nb_channels * s->sample_rate); s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0)) + 2;   bps1 = bps; if (s->nb_channels == 2) bps1 = bps * 1.6; if (sample_rate1 == 44100) { if (bps1 >= 0.61) s->use_noise_coding = 0; else high_freq = high_freq * 0.4; } else if (sample_rate1 == 22050) { if (bps1 >= 1.16) s->use_noise_coding = 0; else if (bps1 >= 0.72) high_freq = high_freq * 0.7; else high_freq = high_freq * 0.6; } else if (sample_rate1 == 16000) { if (bps > 0.5) high_freq = high_freq * 0.5; else high_freq = high_freq * 0.3; } else if (sample_rate1 == 11025) { high_freq = high_freq * 0.7; } else if (sample_rate1 == 8000) { if (bps <= 0.625) { high_freq = high_freq * 0.5; } else if (bps > 0.75) { s->use_noise_coding = 0; } else { high_freq = high_freq * 0.65; } } else { if (bps >= 0.8) { high_freq = high_freq * 0.75; } else if (bps >= 0.6) { high_freq = high_freq * 0.6; } else { high_freq = high_freq * 0.5; } } dprintf("flags1=0x%x flags2=0x%x\n", flags1, flags2); dprintf("version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n", s->version, s->nb_channels, s->sample_rate, s->bit_rate, s->block_align); dprintf("bps=%f bps1=%f high_freq=%f bitoffset=%d\n", bps, bps1, high_freq, s->byte_offset_bits); dprintf("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n", s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);   { int a, b, pos, lpos, k, block_len, i, j, n; const uint8_t *table; if (s->version == 1) { s->coefs_start = 3; } else { s->coefs_start = 0; } for(k = 0; k < s->nb_block_sizes; k++) { block_len = s->frame_len >> k; if (s->version == 1) { lpos = 0; for(i=0;i<25;i++) { a = wma_critical_freqs[i]; b = s->sample_rate; pos = ((block_len * 2 * a) + (b >> 1)) / b; if (pos > block_len) pos = block_len; s->exponent_bands[0][i] = pos - lpos; if (pos >= block_len) { i++; break; } lpos = pos; } s->exponent_sizes[0] = i; } else {   table = NULL; a = s->frame_len_bits - BLOCK_MIN_BITS - k; if (a < 3) { if (s->sample_rate >= 44100) table = exponent_band_44100[a]; else if (s->sample_rate >= 32000) table = exponent_band_32000[a]; else if (s->sample_rate >= 22050) table = exponent_band_22050[a]; } if (table) { n = *table++; for(i=0;i<n;i++) s->exponent_bands[k][i] = table[i]; s->exponent_sizes[k] = n; } else { j = 0; lpos = 0; for(i=0;i<25;i++) { a = wma_critical_freqs[i]; b = s->sample_rate; pos = ((block_len * 2 * a) + (b << 1)) / (4 * b); pos <<= 2; if (pos > block_len) pos = block_len; if (pos > lpos) s->exponent_bands[k][j++] = pos - lpos; if (pos >= block_len) break; lpos = pos; } s->exponent_sizes[k] = j; } }   s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;   s->high_band_start[k] = (int)((block_len * 2 * high_freq) / s->sample_rate + 0.5); n = s->exponent_sizes[k]; j = 0; pos = 0; for(i=0;i<n;i++) { int start, end; start = pos; pos += s->exponent_bands[k][i]; end = pos; if (start < s->high_band_start[k]) start = s->high_band_start[k]; if (end > s->coefs_end[k]) end = s->coefs_end[k]; if (end > start) s->exponent_high_bands[k][j++] = end - start; } s->exponent_high_sizes[k] = j; #if 0 tprintf("%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ", s->frame_len >> k, s->coefs_end[k], s->high_band_start[k], s->exponent_high_sizes[k]); for(j=0;j<s->exponent_high_sizes[k];j++) tprintf(" %d", s->exponent_high_bands[k][j]); tprintf("\n"); #endif } } #ifdef TRACE { int i, j; for(i = 0; i < s->nb_block_sizes; i++) { tprintf("%5d: n=%2d:", s->frame_len >> i, s->exponent_sizes[i]); for(j=0;j<s->exponent_sizes[i];j++) tprintf(" %d", s->exponent_bands[i][j]); tprintf("\n"); } } #endif   for(i = 0; i < s->nb_block_sizes; i++) ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1);   for(i = 0; i < s->nb_block_sizes; i++) { int n, j; float alpha; n = 1 << (s->frame_len_bits - i); window = av_malloc(sizeof(float) * n); alpha = M_PI / (2.0 * n); for(j=0;j<n;j++) { window[n - j - 1] = sin((j + 0.5) * alpha); } s->windows[i] = window; } s->reset_block_lengths = 1; if (s->use_noise_coding) {   if (s->use_exp_vlc) s->noise_mult = 0.02; else s->noise_mult = 0.04; #ifdef TRACE for(i=0;i<NOISE_TAB_SIZE;i++) s->noise_table[i] = 1.0 * s->noise_mult; #else { unsigned int seed; float norm; seed = 1; norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult; for(i=0;i<NOISE_TAB_SIZE;i++) { seed = seed * 314159 + 1; s->noise_table[i] = (float)((int)seed) * norm; } } #endif init_vlc(&s->hgain_vlc, 9, sizeof(hgain_huffbits), hgain_huffbits, 1, 1, hgain_huffcodes, 2, 2); } if (s->use_exp_vlc) { init_vlc(&s->exp_vlc, 9, sizeof(scale_huffbits), scale_huffbits, 1, 1, scale_huffcodes, 4, 4); } else { wma_lsp_to_curve_init(s, s->frame_len); }   coef_vlc_table = 2; if (s->sample_rate >= 32000) { if (bps1 < 0.72) coef_vlc_table = 0; else if (bps1 < 1.16) coef_vlc_table = 1; } init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0], &coef_vlcs[coef_vlc_table * 2]); init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1], &coef_vlcs[coef_vlc_table * 2 + 1]); return 0; }