int ff_wma_init(AVCodecContext *avctx, int flags2) { WMACodecContext *s = avctx->priv_data; int i; float bps1, high_freq; volatile float bps; int sample_rate1; int coef_vlc_table; if ( avctx->sample_rate <= 0 || avctx->sample_rate > 50000 || avctx->channels <= 0 || avctx->channels > 2 || avctx->bit_rate <= 0) return -1; ff_fmt_convert_init(&s->fmt_conv, avctx); avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT); if (avctx->codec->id == AV_CODEC_ID_WMAV1) { s->version = 1; } else { s->version = 2; /* compute MDCT block size */ s->frame_len_bits = ff_wma_get_frame_len_bits(avctx->sample_rate, s->version, 0); s->next_block_len_bits = s->frame_len_bits; s->prev_block_len_bits = s->frame_len_bits; s->block_len_bits = s->frame_len_bits; s->frame_len = 1 << s->frame_len_bits; if (s->use_variable_block_len) { int nb_max, nb; nb = ((flags2 >> 3) & 3) + 1; if ((avctx->bit_rate / avctx->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 dependent parameters */ s->use_noise_coding = 1; high_freq = avctx->sample_rate * 0.5; /* if version 2, then the rates are normalized */ sample_rate1 = avctx->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)avctx->bit_rate / (float)(avctx->channels * avctx->sample_rate); s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0 + 0.5)) + 2; /* compute high frequency value and choose if noise coding should be activated */ bps1 = bps; if (avctx->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; av_dlog(s->avctx, "flags2=0x%x\n", flags2); av_dlog(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n", s->version, avctx->channels, avctx->sample_rate, avctx->bit_rate, avctx->block_align); av_dlog(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n", bps, bps1, high_freq, s->byte_offset_bits); av_dlog(s->avctx, "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 = ff_wma_critical_freqs[i]; b = avctx->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 (avctx->sample_rate >= 44100) { table = exponent_band_44100[a]; } else if (avctx->sample_rate >= 32000) { table = exponent_band_32000[a]; } else if (avctx->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 = ff_wma_critical_freqs[i]; b = avctx->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) / avctx->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(s->avctx, "%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(s->avctx, " %d", s->exponent_high_bands[k][j]); tprintf(s->avctx, "\n"); #endif #ifdef TRACE { int i, j; for (i = 0; i < s->nb_block_sizes; i++) { tprintf(s->avctx, "%5d: n=%2d:", s->frame_len >> i, s->exponent_sizes[i]); for (j = 0; j < s->exponent_sizes[i]; j++) tprintf(s->avctx, " %d", s->exponent_bands[i][j]); tprintf(s->avctx, "\n"); #endif /* init MDCT windows : simple sinus window */ for (i = 0; i < s->nb_block_sizes; i++) { ff_init_ff_sine_windows(s->frame_len_bits - i); s->windows[i] = ff_sine_windows[s->frame_len_bits - i]; 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 /* choose the VLC tables for the coefficients */ coef_vlc_table = 2; if (avctx->sample_rate >= 32000) { if (bps1 < 0.72) { coef_vlc_table = 0; } else if (bps1 < 1.16) { coef_vlc_table = 1; s->coef_vlcs[0]= &coef_vlcs[coef_vlc_table * 2 ]; s->coef_vlcs[1]= &coef_vlcs[coef_vlc_table * 2 + 1]; init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0], &s->int_table[0], s->coef_vlcs[0]); init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1], &s->int_table[1], s->coef_vlcs[1]); return 0;