static void synthfilt_build_sb_samples (QDM2Context *q, GetBitContext *gb, int length, int sb_min, int sb_max) { int sb, j, k, n, ch, run, channels; int joined_stereo, zero_encoding, chs; int type34_first; float type34_div = 0; float type34_predictor; float samples[10], sign_bits[16]; if (length == 0) { // If no data use noise for (sb=sb_min; sb < sb_max; sb++) build_sb_samples_from_noise (q, sb); return; } for (sb = sb_min; sb < sb_max; sb++) { FIX_NOISE_IDX(q->noise_idx); channels = q->nb_channels; if (q->nb_channels <= 1 || sb < 12) joined_stereo = 0; else if (sb >= 24) joined_stereo = 1; else joined_stereo = (BITS_LEFT(length,gb) >= 1) ? get_bits1 (gb) : 0; if (joined_stereo) { if (BITS_LEFT(length,gb) >= 16) for (j = 0; j < 16; j++) sign_bits[j] = get_bits1 (gb); for (j = 0; j < 64; j++) if (q->coding_method[1][sb][j] > q->coding_method[0][sb][j]) q->coding_method[0][sb][j] = q->coding_method[1][sb][j]; fix_coding_method_array(sb, q->nb_channels, q->coding_method); channels = 1; } for (ch = 0; ch < channels; ch++) { zero_encoding = (BITS_LEFT(length,gb) >= 1) ? get_bits1(gb) : 0; type34_predictor = 0.0; type34_first = 1; for (j = 0; j < 128; ) { switch (q->coding_method[ch][sb][j / 2]) { case 8: if (BITS_LEFT(length,gb) >= 10) { if (zero_encoding) { for (k = 0; k < 5; k++) { if ((j + 2 * k) >= 128) break; samples[2 * k] = get_bits1(gb) ? dequant_1bit[joined_stereo][2 * get_bits1(gb)] : 0; } } else { n = get_bits(gb, 8); for (k = 0; k < 5; k++) samples[2 * k] = dequant_1bit[joined_stereo][random_dequant_index[n][k]]; } for (k = 0; k < 5; k++) samples[2 * k + 1] = SB_DITHERING_NOISE(sb,q->noise_idx); } else { for (k = 0; k < 10; k++) samples[k] = SB_DITHERING_NOISE(sb,q->noise_idx); } run = 10; break; case 10: if (BITS_LEFT(length,gb) >= 1) { float f = 0.81; if (get_bits1(gb)) f = -f; f -= noise_samples[((sb + 1) * (j +5 * ch + 1)) & 127] * 9.0 / 40.0; samples[0] = f; } else { samples[0] = SB_DITHERING_NOISE(sb,q->noise_idx); } run = 1; break; case 16: if (BITS_LEFT(length,gb) >= 10) { if (zero_encoding) { for (k = 0; k < 5; k++) { if ((j + k) >= 128) break; samples[k] = (get_bits1(gb) == 0) ? 0 : dequant_1bit[joined_stereo][2 * get_bits1(gb)]; } } else { n = get_bits (gb, 8); for (k = 0; k < 5; k++) samples[k] = dequant_1bit[joined_stereo][random_dequant_index[n][k]]; } } else { for (k = 0; k < 5; k++) samples[k] = SB_DITHERING_NOISE(sb,q->noise_idx); } run = 5; break; case 24: if (BITS_LEFT(length,gb) >= 7) { n = get_bits(gb, 7); for (k = 0; k < 3; k++) samples[k] = (random_dequant_type24[n][k] - 2.0) * 0.5; } else { for (k = 0; k < 3; k++) samples[k] = SB_DITHERING_NOISE(sb,q->noise_idx); } run = 3; break; case 30: if (BITS_LEFT(length,gb) >= 4) samples[0] = type30_dequant[qdm2_get_vlc(gb, &vlc_tab_type30, 0, 1)]; else samples[0] = SB_DITHERING_NOISE(sb,q->noise_idx); run = 1; break; case 34: if (BITS_LEFT(length,gb) >= 7) { if (type34_first) { type34_div = (float)(1 << get_bits(gb, 2)); samples[0] = ((float)get_bits(gb, 5) - 16.0) / 15.0; type34_predictor = samples[0]; type34_first = 0; } else { samples[0] = type34_delta[qdm2_get_vlc(gb, &vlc_tab_type34, 0, 1)] / type34_div + type34_predictor; type34_predictor = samples[0]; } } else { samples[0] = SB_DITHERING_NOISE(sb,q->noise_idx); } run = 1; break; default: samples[0] = SB_DITHERING_NOISE(sb,q->noise_idx); run = 1; break; } if (joined_stereo) { float tmp[10][MPA_MAX_CHANNELS]; for (k = 0; k < run; k++) { tmp[k][0] = samples[k]; tmp[k][1] = (sign_bits[(j + k) / 8]) ? -samples[k] : samples[k]; } for (chs = 0; chs < q->nb_channels; chs++) for (k = 0; k < run; k++) if ((j + k) < 128) q->sb_samples[chs][j + k][sb] = q->tone_level[chs][sb][((j + k)/2)] * tmp[k][chs]; } else { for (k = 0; k < run; k++) if ((j + k) < 128) q->sb_samples[ch][j + k][sb] = q->tone_level[ch][sb][(j + k)/2] * samples[k]; } j += run; } // j loop } // channel loop } // subband loop }