update_lowband = (b > band_size << 3);
}
}
+
+#define NORMC(bits) ((bits) << (f->channels - 1) << f->size >> 2)
+
+void ff_celt_bitalloc(CeltFrame *f, OpusRangeCoder *rc, int encode)
+{
+ int i, j, low, high, total, done, bandbits, remaining, tbits_8ths;
+ int skip_startband = f->start_band;
+ int skip_bit = 0;
+ int intensitystereo_bit = 0;
+ int dualstereo_bit = 0;
+ int dynalloc = 6;
+ int extrabits = 0;
+
+ int boost[CELT_MAX_BANDS] = { 0 };
+ int trim_offset[CELT_MAX_BANDS];
+ int threshold[CELT_MAX_BANDS];
+ int bits1[CELT_MAX_BANDS];
+ int bits2[CELT_MAX_BANDS];
+
+ /* Spread */
+ if (opus_rc_tell(rc) + 4 <= f->framebits) {
+ if (encode)
+ ff_opus_rc_enc_cdf(rc, f->spread, ff_celt_model_spread);
+ else
+ f->spread = ff_opus_rc_dec_cdf(rc, ff_celt_model_spread);
+ } else {
+ f->spread = CELT_SPREAD_NORMAL;
+ }
+
+ /* Initialize static allocation caps */
+ for (i = 0; i < CELT_MAX_BANDS; i++)
+ f->caps[i] = NORMC((ff_celt_static_caps[f->size][f->channels - 1][i] + 64) * ff_celt_freq_range[i]);
+
+ /* Band boosts */
+ tbits_8ths = f->framebits << 3;
+ for (i = f->start_band; i < f->end_band; i++) {
+ int quanta = ff_celt_freq_range[i] << (f->channels - 1) << f->size;
+ int b_dynalloc = dynalloc;
+ int boost_amount = f->alloc_boost[i];
+ quanta = FFMIN(quanta << 3, FFMAX(6 << 3, quanta));
+
+ while (opus_rc_tell_frac(rc) + (b_dynalloc << 3) < tbits_8ths && boost[i] < f->caps[i]) {
+ int is_boost;
+ if (encode) {
+ is_boost = boost_amount--;
+ ff_opus_rc_enc_log(rc, is_boost, b_dynalloc);
+ } else {
+ is_boost = ff_opus_rc_dec_log(rc, b_dynalloc);
+ }
+
+ if (!is_boost)
+ break;
+
+ boost[i] += quanta;
+ tbits_8ths -= quanta;
+
+ b_dynalloc = 1;
+ }
+
+ if (boost[i])
+ dynalloc = FFMAX(dynalloc - 1, 2);
+ }
+
+ /* Allocation trim */
+ if (opus_rc_tell_frac(rc) + (6 << 3) <= tbits_8ths)
+ if (encode)
+ ff_opus_rc_enc_cdf(rc, f->alloc_trim, ff_celt_model_alloc_trim);
+ else
+ f->alloc_trim = ff_opus_rc_dec_cdf(rc, ff_celt_model_alloc_trim);
+
+ /* Anti-collapse bit reservation */
+ tbits_8ths = (f->framebits << 3) - opus_rc_tell_frac(rc) - 1;
+ f->anticollapse_needed = 0;
+ if (f->transient && f->size >= 2 && tbits_8ths >= ((f->size + 2) << 3))
+ f->anticollapse_needed = 1 << 3;
+ tbits_8ths -= f->anticollapse_needed;
+
+ /* Band skip bit reservation */
+ if (tbits_8ths >= 1 << 3)
+ skip_bit = 1 << 3;
+ tbits_8ths -= skip_bit;
+
+ /* Intensity/dual stereo bit reservation */
+ if (f->channels == 2) {
+ intensitystereo_bit = ff_celt_log2_frac[f->end_band - f->start_band];
+ if (intensitystereo_bit <= tbits_8ths) {
+ tbits_8ths -= intensitystereo_bit;
+ if (tbits_8ths >= 1 << 3) {
+ dualstereo_bit = 1 << 3;
+ tbits_8ths -= 1 << 3;
+ }
+ } else {
+ intensitystereo_bit = 0;
+ }
+ }
+
+ /* Trim offsets */
+ for (i = f->start_band; i < f->end_band; i++) {
+ int trim = f->alloc_trim - 5 - f->size;
+ int band = ff_celt_freq_range[i] * (f->end_band - i - 1);
+ int duration = f->size + 3;
+ int scale = duration + f->channels - 1;
+
+ /* PVQ minimum allocation threshold, below this value the band is
+ * skipped */
+ threshold[i] = FFMAX(3 * ff_celt_freq_range[i] << duration >> 4,
+ f->channels << 3);
+
+ trim_offset[i] = trim * (band << scale) >> 6;
+
+ if (ff_celt_freq_range[i] << f->size == 1)
+ trim_offset[i] -= f->channels << 3;
+ }
+
+ /* Bisection */
+ low = 1;
+ high = CELT_VECTORS - 1;
+ while (low <= high) {
+ int center = (low + high) >> 1;
+ done = total = 0;
+
+ for (i = f->end_band - 1; i >= f->start_band; i--) {
+ bandbits = NORMC(ff_celt_freq_range[i] * ff_celt_static_alloc[center][i]);
+
+ if (bandbits)
+ bandbits = FFMAX(bandbits + trim_offset[i], 0);
+ bandbits += boost[i];
+
+ if (bandbits >= threshold[i] || done) {
+ done = 1;
+ total += FFMIN(bandbits, f->caps[i]);
+ } else if (bandbits >= f->channels << 3) {
+ total += f->channels << 3;
+ }
+ }
+
+ if (total > tbits_8ths)
+ high = center - 1;
+ else
+ low = center + 1;
+ }
+ high = low--;
+
+ /* Bisection */
+ for (i = f->start_band; i < f->end_band; i++) {
+ bits1[i] = NORMC(ff_celt_freq_range[i] * ff_celt_static_alloc[low][i]);
+ bits2[i] = high >= CELT_VECTORS ? f->caps[i] :
+ NORMC(ff_celt_freq_range[i] * ff_celt_static_alloc[high][i]);
+
+ if (bits1[i])
+ bits1[i] = FFMAX(bits1[i] + trim_offset[i], 0);
+ if (bits2[i])
+ bits2[i] = FFMAX(bits2[i] + trim_offset[i], 0);
+
+ if (low)
+ bits1[i] += boost[i];
+ bits2[i] += boost[i];
+
+ if (boost[i])
+ skip_startband = i;
+ bits2[i] = FFMAX(bits2[i] - bits1[i], 0);
+ }
+
+ /* Bisection */
+ low = 0;
+ high = 1 << CELT_ALLOC_STEPS;
+ for (i = 0; i < CELT_ALLOC_STEPS; i++) {
+ int center = (low + high) >> 1;
+ done = total = 0;
+
+ for (j = f->end_band - 1; j >= f->start_band; j--) {
+ bandbits = bits1[j] + (center * bits2[j] >> CELT_ALLOC_STEPS);
+
+ if (bandbits >= threshold[j] || done) {
+ done = 1;
+ total += FFMIN(bandbits, f->caps[j]);
+ } else if (bandbits >= f->channels << 3)
+ total += f->channels << 3;
+ }
+ if (total > tbits_8ths)
+ high = center;
+ else
+ low = center;
+ }
+
+ /* Bisection */
+ done = total = 0;
+ for (i = f->end_band - 1; i >= f->start_band; i--) {
+ bandbits = bits1[i] + (low * bits2[i] >> CELT_ALLOC_STEPS);
+
+ if (bandbits >= threshold[i] || done)
+ done = 1;
+ else
+ bandbits = (bandbits >= f->channels << 3) ?
+ f->channels << 3 : 0;
+
+ bandbits = FFMIN(bandbits, f->caps[i]);
+ f->pulses[i] = bandbits;
+ total += bandbits;
+ }
+
+ /* Band skipping */
+ for (f->coded_bands = f->end_band; ; f->coded_bands--) {
+ int allocation;
+ j = f->coded_bands - 1;
+
+ if (j == skip_startband) {
+ /* all remaining bands are not skipped */
+ tbits_8ths += skip_bit;
+ break;
+ }
+
+ /* determine the number of bits available for coding "do not skip" markers */
+ remaining = tbits_8ths - total;
+ bandbits = remaining / (ff_celt_freq_bands[j+1] - ff_celt_freq_bands[f->start_band]);
+ remaining -= bandbits * (ff_celt_freq_bands[j+1] - ff_celt_freq_bands[f->start_band]);
+ allocation = f->pulses[j] + bandbits * ff_celt_freq_range[j];
+ allocation += FFMAX(remaining - (ff_celt_freq_bands[j] - ff_celt_freq_bands[f->start_band]), 0);
+
+ /* a "do not skip" marker is only coded if the allocation is
+ * above the chosen threshold */
+ if (allocation >= FFMAX(threshold[j], (f->channels + 1) << 3)) {
+ int do_not_skip;
+ if (encode) {
+ do_not_skip = f->coded_bands <= f->skip_band_floor;
+ ff_opus_rc_enc_log(rc, do_not_skip, 1);
+ } else {
+ do_not_skip = ff_opus_rc_dec_log(rc, 1);
+ }
+
+ if (do_not_skip)
+ break;
+
+ total += 1 << 3;
+ allocation -= 1 << 3;
+ }
+
+ /* the band is skipped, so reclaim its bits */
+ total -= f->pulses[j];
+ if (intensitystereo_bit) {
+ total -= intensitystereo_bit;
+ intensitystereo_bit = ff_celt_log2_frac[j - f->start_band];
+ total += intensitystereo_bit;
+ }
+
+ total += f->pulses[j] = (allocation >= f->channels << 3) ? f->channels << 3 : 0;
+ }
+
+ /* IS start band */
+ if (encode) {
+ if (intensitystereo_bit) {
+ f->intensity_stereo = FFMIN(f->intensity_stereo, f->coded_bands);
+ ff_opus_rc_enc_uint(rc, f->intensity_stereo, f->coded_bands + 1 - f->start_band);
+ }
+ } else {
+ f->intensity_stereo = f->dual_stereo = 0;
+ if (intensitystereo_bit)
+ f->intensity_stereo = f->start_band + ff_opus_rc_dec_uint(rc, f->coded_bands + 1 - f->start_band);
+ }
+
+ /* DS flag */
+ if (f->intensity_stereo <= f->start_band)
+ tbits_8ths += dualstereo_bit; /* no intensity stereo means no dual stereo */
+ else if (dualstereo_bit)
+ if (encode)
+ ff_opus_rc_enc_log(rc, f->dual_stereo, 1);
+ else
+ f->dual_stereo = ff_opus_rc_dec_log(rc, 1);
+
+ /* Supply the remaining bits in this frame to lower bands */
+ remaining = tbits_8ths - total;
+ bandbits = remaining / (ff_celt_freq_bands[f->coded_bands] - ff_celt_freq_bands[f->start_band]);
+ remaining -= bandbits * (ff_celt_freq_bands[f->coded_bands] - ff_celt_freq_bands[f->start_band]);
+ for (i = f->start_band; i < f->coded_bands; i++) {
+ const int bits = FFMIN(remaining, ff_celt_freq_range[i]);
+ f->pulses[i] += bits + bandbits * ff_celt_freq_range[i];
+ remaining -= bits;
+ }
+
+ /* Finally determine the allocation */
+ for (i = f->start_band; i < f->coded_bands; i++) {
+ int N = ff_celt_freq_range[i] << f->size;
+ int prev_extra = extrabits;
+ f->pulses[i] += extrabits;
+
+ if (N > 1) {
+ int dof; /* degrees of freedom */
+ int temp; /* dof * channels * log(dof) */
+ int fine_bits;
+ int max_bits;
+ int offset; /* fine energy quantization offset, i.e.
+ * extra bits assigned over the standard
+ * totalbits/dof */
+
+ extrabits = FFMAX(f->pulses[i] - f->caps[i], 0);
+ f->pulses[i] -= extrabits;
+
+ /* intensity stereo makes use of an extra degree of freedom */
+ dof = N * f->channels + (f->channels == 2 && N > 2 && !f->dual_stereo && i < f->intensity_stereo);
+ temp = dof * (ff_celt_log_freq_range[i] + (f->size << 3));
+ offset = (temp >> 1) - dof * CELT_FINE_OFFSET;
+ if (N == 2) /* dof=2 is the only case that doesn't fit the model */
+ offset += dof << 1;
+
+ /* grant an additional bias for the first and second pulses */
+ if (f->pulses[i] + offset < 2 * (dof << 3))
+ offset += temp >> 2;
+ else if (f->pulses[i] + offset < 3 * (dof << 3))
+ offset += temp >> 3;
+
+ fine_bits = (f->pulses[i] + offset + (dof << 2)) / (dof << 3);
+ max_bits = FFMIN((f->pulses[i] >> 3) >> (f->channels - 1), CELT_MAX_FINE_BITS);
+ max_bits = FFMAX(max_bits, 0);
+ f->fine_bits[i] = av_clip(fine_bits, 0, max_bits);
+
+ /* If fine_bits was rounded down or capped,
+ * give priority for the final fine energy pass */
+ f->fine_priority[i] = (f->fine_bits[i] * (dof << 3) >= f->pulses[i] + offset);
+
+ /* the remaining bits are assigned to PVQ */
+ f->pulses[i] -= f->fine_bits[i] << (f->channels - 1) << 3;
+ } else {
+ /* all bits go to fine energy except for the sign bit */
+ extrabits = FFMAX(f->pulses[i] - (f->channels << 3), 0);
+ f->pulses[i] -= extrabits;
+ f->fine_bits[i] = 0;
+ f->fine_priority[i] = 1;
+ }
+
+ /* hand back a limited number of extra fine energy bits to this band */
+ if (extrabits > 0) {
+ int fineextra = FFMIN(extrabits >> (f->channels + 2),
+ CELT_MAX_FINE_BITS - f->fine_bits[i]);
+ f->fine_bits[i] += fineextra;
+
+ fineextra <<= f->channels + 2;
+ f->fine_priority[i] = (fineextra >= extrabits - prev_extra);
+ extrabits -= fineextra;
+ }
+ }
+ f->remaining = extrabits;
+
+ /* skipped bands dedicate all of their bits for fine energy */
+ for (; i < f->end_band; i++) {
+ f->fine_bits[i] = f->pulses[i] >> (f->channels - 1) >> 3;
+ f->pulses[i] = 0;
+ f->fine_priority[i] = f->fine_bits[i] < 1;
+ }
+}
projects / ffmpeg / blobdiff