void ff_celt_quant_bands(CeltFrame *f, OpusRangeCoder *rc) { float lowband_scratch[8 * 22]; float norm1[2 * 8 * 100]; float *norm2 = norm1 + 8 * 100; int totalbits = (f->framebits << 3) - f->anticollapse_needed; int update_lowband = 1; int lowband_offset = 0; int i, j; for (i = f->start_band; i < f->end_band; i++) { uint32_t cm[2] = { (1 << f->blocks) - 1, (1 << f->blocks) - 1 }; int band_offset = ff_celt_freq_bands[i] << f->size; int band_size = ff_celt_freq_range[i] << f->size; float *X = f->block[0].coeffs + band_offset; float *Y = (f->channels == 2) ? f->block[1].coeffs + band_offset : NULL; float *norm_loc1, *norm_loc2; int consumed = opus_rc_tell_frac(rc); int effective_lowband = -1; int b = 0; /* Compute how many bits we want to allocate to this band */ if (i != f->start_band) f->remaining -= consumed; f->remaining2 = totalbits - consumed - 1; if (i <= f->coded_bands - 1) { int curr_balance = f->remaining / FFMIN(3, f->coded_bands-i); b = av_clip_uintp2(FFMIN(f->remaining2 + 1, f->pulses[i] + curr_balance), 14); } if ((ff_celt_freq_bands[i] - ff_celt_freq_range[i] >= ff_celt_freq_bands[f->start_band] || i == f->start_band + 1) && (update_lowband || lowband_offset == 0)) lowband_offset = i; if (i == f->start_band + 1) { /* Special Hybrid Folding (RFC 8251 section 9). Copy the first band into the second to ensure the second band never has to use the LCG. */ int offset = 8 * ff_celt_freq_bands[i]; int count = 8 * (ff_celt_freq_range[i] - ff_celt_freq_range[i-1]); memcpy(&norm1[offset], &norm1[offset - count], count * sizeof(float)); if (f->channels == 2) memcpy(&norm2[offset], &norm2[offset - count], count * sizeof(float)); } /* Get a conservative estimate of the collapse_mask's for the bands we're going to be folding from. */ if (lowband_offset != 0 && (f->spread != CELT_SPREAD_AGGRESSIVE || f->blocks > 1 || f->tf_change[i] < 0)) { int foldstart, foldend; /* This ensures we never repeat spectral content within one band */ effective_lowband = FFMAX(ff_celt_freq_bands[f->start_band], ff_celt_freq_bands[lowband_offset] - ff_celt_freq_range[i]); foldstart = lowband_offset; while (ff_celt_freq_bands[--foldstart] > effective_lowband); foldend = lowband_offset - 1; while (++foldend < i && ff_celt_freq_bands[foldend] < effective_lowband + ff_celt_freq_range[i]); cm[0] = cm[1] = 0; for (j = foldstart; j < foldend; j++) { cm[0] |= f->block[0].collapse_masks[j]; cm[1] |= f->block[f->channels - 1].collapse_masks[j]; } } if (f->dual_stereo && i == f->intensity_stereo) { /* Switch off dual stereo to do intensity */ f->dual_stereo = 0; for (j = ff_celt_freq_bands[f->start_band] << f->size; j < band_offset; j++) norm1[j] = (norm1[j] + norm2[j]) / 2; } norm_loc1 = effective_lowband != -1 ? norm1 + (effective_lowband << f->size) : NULL; norm_loc2 = effective_lowband != -1 ? norm2 + (effective_lowband << f->size) : NULL; if (f->dual_stereo) { cm[0] = f->pvq->quant_band(f->pvq, f, rc, i, X, NULL, band_size, b >> 1, f->blocks, norm_loc1, f->size, norm1 + band_offset, 0, 1.0f, lowband_scratch, cm[0]); cm[1] = f->pvq->quant_band(f->pvq, f, rc, i, Y, NULL, band_size, b >> 1, f->blocks, norm_loc2, f->size, norm2 + band_offset, 0, 1.0f, lowband_scratch, cm[1]); } else { cm[0] = f->pvq->quant_band(f->pvq, f, rc, i, X, Y, band_size, b >> 0, f->blocks, norm_loc1, f->size, norm1 + band_offset, 0, 1.0f, lowband_scratch, cm[0] | cm[1]); cm[1] = cm[0]; } f->block[0].collapse_masks[i] = (uint8_t)cm[0]; f->block[f->channels - 1].collapse_masks[i] = (uint8_t)cm[1]; f->remaining += f->pulses[i] + consumed; /* Update the folding position only as long as we have 1 bit/sample depth */ update_lowband = (b > band_size << 3); } }