dca_xll.c 49.5 KB
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/*
 * Copyright (C) 2016 foo86
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "dcadec.h"
#include "dcadata.h"
#include "dcamath.h"
#include "dca_syncwords.h"
#include "unary.h"

static int get_linear(GetBitContext *gb, int n)
{
    unsigned int v = get_bits_long(gb, n);
    return (v >> 1) ^ -(v & 1);
}

static int get_rice_un(GetBitContext *gb, int k)
{
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    unsigned int v = get_unary(gb, 1, get_bits_left(gb));
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    return (v << k) | get_bits_long(gb, k);
}

static int get_rice(GetBitContext *gb, int k)
{
    unsigned int v = get_rice_un(gb, k);
    return (v >> 1) ^ -(v & 1);
}

static void get_array(GetBitContext *gb, int32_t *array, int size, int n)
{
    int i;

    for (i = 0; i < size; i++)
        array[i] = get_bits(gb, n);
}

static void get_linear_array(GetBitContext *gb, int32_t *array, int size, int n)
{
    int i;

    if (n == 0)
        memset(array, 0, sizeof(*array) * size);
    else for (i = 0; i < size; i++)
        array[i] = get_linear(gb, n);
}

static void get_rice_array(GetBitContext *gb, int32_t *array, int size, int k)
{
    int i;

    for (i = 0; i < size; i++)
        array[i] = get_rice(gb, k);
}

static int parse_dmix_coeffs(DCAXllDecoder *s, DCAXllChSet *c)
{
    // Size of downmix coefficient matrix
    int m = c->primary_chset ? ff_dca_dmix_primary_nch[c->dmix_type] : c->hier_ofs;
    int i, j, *coeff_ptr = c->dmix_coeff;

    for (i = 0; i < m; i++) {
        int code, sign, coeff, scale, scale_inv = 0;
        unsigned int index;

        // Downmix scale (only for non-primary channel sets)
        if (!c->primary_chset) {
            code = get_bits(&s->gb, 9);
            sign = (code >> 8) - 1;
            index = (code & 0xff) - FF_DCA_DMIXTABLE_OFFSET;
            if (index >= FF_DCA_INV_DMIXTABLE_SIZE) {
                av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL downmix scale index\n");
                return AVERROR_INVALIDDATA;
            }
            scale = ff_dca_dmixtable[index + FF_DCA_DMIXTABLE_OFFSET];
            scale_inv = ff_dca_inv_dmixtable[index];
            c->dmix_scale[i] = (scale ^ sign) - sign;
            c->dmix_scale_inv[i] = (scale_inv ^ sign) - sign;
        }

        // Downmix coefficients
        for (j = 0; j < c->nchannels; j++) {
            code = get_bits(&s->gb, 9);
            sign = (code >> 8) - 1;
            index = code & 0xff;
            if (index >= FF_DCA_DMIXTABLE_SIZE) {
                av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL downmix coefficient index\n");
                return AVERROR_INVALIDDATA;
            }
            coeff = ff_dca_dmixtable[index];
            if (!c->primary_chset)
                // Multiply by |InvDmixScale| to get |UndoDmixScale|
                coeff = mul16(scale_inv, coeff);
            *coeff_ptr++ = (coeff ^ sign) - sign;
        }
    }

    return 0;
}

static int chs_parse_header(DCAXllDecoder *s, DCAXllChSet *c, DCAExssAsset *asset)
{
    int i, j, k, ret, band, header_size, header_pos = get_bits_count(&s->gb);
    DCAXllChSet *p = &s->chset[0];
    DCAXllBand *b;

    // Size of channel set sub-header
    header_size = get_bits(&s->gb, 10) + 1;

    // Check CRC
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    if (ff_dca_check_crc(s->avctx, &s->gb, header_pos, header_pos + header_size * 8)) {
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        av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL sub-header checksum\n");
        return AVERROR_INVALIDDATA;
    }

    // Number of channels in the channel set
    c->nchannels = get_bits(&s->gb, 4) + 1;
    if (c->nchannels > DCA_XLL_CHANNELS_MAX) {
        avpriv_request_sample(s->avctx, "%d XLL channels", c->nchannels);
        return AVERROR_PATCHWELCOME;
    }

    // Residual type
    c->residual_encode = get_bits(&s->gb, c->nchannels);

    // PCM bit resolution
    c->pcm_bit_res = get_bits(&s->gb, 5) + 1;

    // Storage unit width
    c->storage_bit_res = get_bits(&s->gb, 5) + 1;
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    if (c->storage_bit_res != 16 && c->storage_bit_res != 20 && c->storage_bit_res != 24) {
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        avpriv_request_sample(s->avctx, "%d-bit XLL storage resolution", c->storage_bit_res);
        return AVERROR_PATCHWELCOME;
    }

    if (c->pcm_bit_res > c->storage_bit_res) {
        av_log(s->avctx, AV_LOG_ERROR, "Invalid PCM bit resolution for XLL channel set (%d > %d)\n", c->pcm_bit_res, c->storage_bit_res);
        return AVERROR_INVALIDDATA;
    }

    // Original sampling frequency
    c->freq = ff_dca_sampling_freqs[get_bits(&s->gb, 4)];
    if (c->freq > 192000) {
        avpriv_request_sample(s->avctx, "%d Hz XLL sampling frequency", c->freq);
        return AVERROR_PATCHWELCOME;
    }

    // Sampling frequency modifier
    if (get_bits(&s->gb, 2)) {
        avpriv_request_sample(s->avctx, "XLL sampling frequency modifier");
        return AVERROR_PATCHWELCOME;
    }

    // Which replacement set this channel set is member of
    if (get_bits(&s->gb, 2)) {
        avpriv_request_sample(s->avctx, "XLL replacement set");
        return AVERROR_PATCHWELCOME;
    }

    if (asset->one_to_one_map_ch_to_spkr) {
        // Primary channel set flag
        c->primary_chset = get_bits1(&s->gb);
        if (c->primary_chset != (c == p)) {
            av_log(s->avctx, AV_LOG_ERROR, "The first (and only) XLL channel set must be primary\n");
            return AVERROR_INVALIDDATA;
        }

        // Downmix coefficients present in stream
        c->dmix_coeffs_present = get_bits1(&s->gb);

        // Downmix already performed by encoder
        c->dmix_embedded = c->dmix_coeffs_present && get_bits1(&s->gb);

        // Downmix type
        if (c->dmix_coeffs_present && c->primary_chset) {
            c->dmix_type = get_bits(&s->gb, 3);
            if (c->dmix_type >= DCA_DMIX_TYPE_COUNT) {
                av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL primary channel set downmix type\n");
                return AVERROR_INVALIDDATA;
            }
        }

        // Whether the channel set is part of a hierarchy
        c->hier_chset = get_bits1(&s->gb);
        if (!c->hier_chset && s->nchsets != 1) {
            avpriv_request_sample(s->avctx, "XLL channel set outside of hierarchy");
            return AVERROR_PATCHWELCOME;
        }

        // Downmix coefficients
        if (c->dmix_coeffs_present && (ret = parse_dmix_coeffs(s, c)) < 0)
            return ret;

        // Channel mask enabled
        if (!get_bits1(&s->gb)) {
            avpriv_request_sample(s->avctx, "Disabled XLL channel mask");
            return AVERROR_PATCHWELCOME;
        }

        // Channel mask for set
        c->ch_mask = get_bits_long(&s->gb, s->ch_mask_nbits);
        if (av_popcount(c->ch_mask) != c->nchannels) {
            av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL channel mask\n");
            return AVERROR_INVALIDDATA;
        }

        // Build the channel to speaker map
        for (i = 0, j = 0; i < s->ch_mask_nbits; i++)
            if (c->ch_mask & (1U << i))
                c->ch_remap[j++] = i;
    } else {
        // Mapping coeffs present flag
        if (c->nchannels != 2 || s->nchsets != 1 || get_bits1(&s->gb)) {
            avpriv_request_sample(s->avctx, "Custom XLL channel to speaker mapping");
            return AVERROR_PATCHWELCOME;
        }

        // Setup for LtRt decoding
        c->primary_chset = 1;
        c->dmix_coeffs_present = 0;
        c->dmix_embedded = 0;
        c->hier_chset = 0;
        c->ch_mask = DCA_SPEAKER_LAYOUT_STEREO;
        c->ch_remap[0] = DCA_SPEAKER_L;
        c->ch_remap[1] = DCA_SPEAKER_R;
    }

    if (c->freq > 96000) {
        // Extra frequency bands flag
        if (get_bits1(&s->gb)) {
            avpriv_request_sample(s->avctx, "Extra XLL frequency bands");
            return AVERROR_PATCHWELCOME;
        }
        c->nfreqbands = 2;
    } else {
        c->nfreqbands = 1;
    }

    // Set the sampling frequency to that of the first frequency band.
    // Frequency will be doubled again after bands assembly.
    c->freq >>= c->nfreqbands - 1;

    // Verify that all channel sets have the same audio characteristics
    if (c != p && (c->nfreqbands != p->nfreqbands || c->freq != p->freq
                   || c->pcm_bit_res != p->pcm_bit_res
                   || c->storage_bit_res != p->storage_bit_res)) {
        avpriv_request_sample(s->avctx, "Different XLL audio characteristics");
        return AVERROR_PATCHWELCOME;
    }

    // Determine number of bits to read bit allocation coding parameter
    if (c->storage_bit_res > 16)
        c->nabits = 5;
    else if (c->storage_bit_res > 8)
        c->nabits = 4;
    else
        c->nabits = 3;

    // Account for embedded downmix and decimator saturation
    if ((s->nchsets > 1 || c->nfreqbands > 1) && c->nabits < 5)
        c->nabits++;

    for (band = 0, b = c->bands; band < c->nfreqbands; band++, b++) {
        // Pairwise channel decorrelation
        if ((b->decor_enabled = get_bits1(&s->gb)) && c->nchannels > 1) {
            int ch_nbits = av_ceil_log2(c->nchannels);

            // Original channel order
            for (i = 0; i < c->nchannels; i++) {
                b->orig_order[i] = get_bits(&s->gb, ch_nbits);
                if (b->orig_order[i] >= c->nchannels) {
                    av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL original channel order\n");
                    return AVERROR_INVALIDDATA;
                }
            }

            // Pairwise channel coefficients
            for (i = 0; i < c->nchannels / 2; i++)
                b->decor_coeff[i] = get_bits1(&s->gb) ? get_linear(&s->gb, 7) : 0;
        } else {
            for (i = 0; i < c->nchannels; i++)
                b->orig_order[i] = i;
            for (i = 0; i < c->nchannels / 2; i++)
                b->decor_coeff[i] = 0;
        }

        // Adaptive predictor order
        b->highest_pred_order = 0;
        for (i = 0; i < c->nchannels; i++) {
            b->adapt_pred_order[i] = get_bits(&s->gb, 4);
            if (b->adapt_pred_order[i] > b->highest_pred_order)
                b->highest_pred_order = b->adapt_pred_order[i];
        }
        if (b->highest_pred_order > s->nsegsamples) {
            av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL adaptive predicition order\n");
            return AVERROR_INVALIDDATA;
        }

        // Fixed predictor order
        for (i = 0; i < c->nchannels; i++)
            b->fixed_pred_order[i] = b->adapt_pred_order[i] ? 0 : get_bits(&s->gb, 2);

        // Adaptive predictor quantized reflection coefficients
        for (i = 0; i < c->nchannels; i++) {
            for (j = 0; j < b->adapt_pred_order[i]; j++) {
                k = get_linear(&s->gb, 8);
                if (k == -128) {
                    av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL reflection coefficient index\n");
                    return AVERROR_INVALIDDATA;
                }
                if (k < 0)
                    b->adapt_refl_coeff[i][j] = -(int)ff_dca_xll_refl_coeff[-k];
                else
                    b->adapt_refl_coeff[i][j] =  (int)ff_dca_xll_refl_coeff[ k];
            }
        }

        // Downmix performed by encoder in extension frequency band
        b->dmix_embedded = c->dmix_embedded && (band == 0 || get_bits1(&s->gb));

        // MSB/LSB split flag in extension frequency band
        if ((band == 0 && s->scalable_lsbs) || (band != 0 && get_bits1(&s->gb))) {
            // Size of LSB section in any segment
            b->lsb_section_size = get_bits_long(&s->gb, s->seg_size_nbits);
            if (b->lsb_section_size < 0 || b->lsb_section_size > s->frame_size) {
                av_log(s->avctx, AV_LOG_ERROR, "Invalid LSB section size\n");
                return AVERROR_INVALIDDATA;
            }

            // Account for optional CRC bytes after LSB section
            if (b->lsb_section_size && (s->band_crc_present > 2 ||
                                        (band == 0 && s->band_crc_present > 1)))
                b->lsb_section_size += 2;

            // Number of bits to represent the samples in LSB part
            for (i = 0; i < c->nchannels; i++) {
                b->nscalablelsbs[i] = get_bits(&s->gb, 4);
                if (b->nscalablelsbs[i] && !b->lsb_section_size) {
                    av_log(s->avctx, AV_LOG_ERROR, "LSB section missing with non-zero LSB width\n");
                    return AVERROR_INVALIDDATA;
                }
            }
        } else {
            b->lsb_section_size = 0;
            for (i = 0; i < c->nchannels; i++)
                b->nscalablelsbs[i] = 0;
        }

        // Scalable resolution flag in extension frequency band
        if ((band == 0 && s->scalable_lsbs) || (band != 0 && get_bits1(&s->gb))) {
            // Number of bits discarded by authoring
            for (i = 0; i < c->nchannels; i++)
                b->bit_width_adjust[i] = get_bits(&s->gb, 4);
        } else {
            for (i = 0; i < c->nchannels; i++)
                b->bit_width_adjust[i] = 0;
        }
    }

    // Reserved
    // Byte align
    // CRC16 of channel set sub-header
    if (ff_dca_seek_bits(&s->gb, header_pos + header_size * 8)) {
        av_log(s->avctx, AV_LOG_ERROR, "Read past end of XLL sub-header\n");
        return AVERROR_INVALIDDATA;
    }

    return 0;
}

static int chs_alloc_msb_band_data(DCAXllDecoder *s, DCAXllChSet *c)
{
    int ndecisamples = c->nfreqbands > 1 ? DCA_XLL_DECI_HISTORY_MAX : 0;
    int nchsamples = s->nframesamples + ndecisamples;
    int i, j, nsamples = nchsamples * c->nchannels * c->nfreqbands;
    int32_t *ptr;

    // Reallocate MSB sample buffer
    av_fast_malloc(&c->sample_buffer[0], &c->sample_size[0], nsamples * sizeof(int32_t));
    if (!c->sample_buffer[0])
        return AVERROR(ENOMEM);

    ptr = c->sample_buffer[0] + ndecisamples;
    for (i = 0; i < c->nfreqbands; i++) {
        for (j = 0; j < c->nchannels; j++) {
            c->bands[i].msb_sample_buffer[j] = ptr;
            ptr += nchsamples;
        }
    }

    return 0;
}

static int chs_alloc_lsb_band_data(DCAXllDecoder *s, DCAXllChSet *c)
{
    int i, j, nsamples = 0;
    int32_t *ptr;

    // Determine number of frequency bands that have MSB/LSB split
    for (i = 0; i < c->nfreqbands; i++)
        if (c->bands[i].lsb_section_size)
            nsamples += s->nframesamples * c->nchannels;
    if (!nsamples)
        return 0;

    // Reallocate LSB sample buffer
    av_fast_malloc(&c->sample_buffer[1], &c->sample_size[1], nsamples * sizeof(int32_t));
    if (!c->sample_buffer[1])
        return AVERROR(ENOMEM);

    ptr = c->sample_buffer[1];
    for (i = 0; i < c->nfreqbands; i++) {
        if (c->bands[i].lsb_section_size) {
            for (j = 0; j < c->nchannels; j++) {
                c->bands[i].lsb_sample_buffer[j] = ptr;
                ptr += s->nframesamples;
            }
        } else {
            for (j = 0; j < c->nchannels; j++)
                c->bands[i].lsb_sample_buffer[j] = NULL;
        }
    }

    return 0;
}

static int chs_parse_band_data(DCAXllDecoder *s, DCAXllChSet *c, int band, int seg, int band_data_end)
{
    DCAXllBand *b = &c->bands[band];
    int i, j, k;

    // Start unpacking MSB portion of the segment
    if (!(seg && get_bits1(&s->gb))) {
        // Unpack segment type
        // 0 - distinct coding parameters for each channel
        // 1 - common coding parameters for all channels
        c->seg_common = get_bits1(&s->gb);

        // Determine number of coding parameters encoded in segment
        k = c->seg_common ? 1 : c->nchannels;

        // Unpack Rice coding parameters
        for (i = 0; i < k; i++) {
            // Unpack Rice coding flag
            // 0 - linear code, 1 - Rice code
            c->rice_code_flag[i] = get_bits1(&s->gb);
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            // Unpack Hybrid Rice coding flag
            // 0 - Rice code, 1 - Hybrid Rice code
            if (!c->seg_common && c->rice_code_flag[i] && get_bits1(&s->gb))
                // Unpack binary code length for isolated samples
                c->bitalloc_hybrid_linear[i] = get_bits(&s->gb, c->nabits) + 1;
            else
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                // 0 indicates no Hybrid Rice coding
                c->bitalloc_hybrid_linear[i] = 0;
        }

        // Unpack coding parameters
        for (i = 0; i < k; i++) {
            if (seg == 0) {
                // Unpack coding parameter for part A of segment 0
                c->bitalloc_part_a[i] = get_bits(&s->gb, c->nabits);

                // Adjust for the linear code
                if (!c->rice_code_flag[i] && c->bitalloc_part_a[i])
                    c->bitalloc_part_a[i]++;

                if (!c->seg_common)
                    c->nsamples_part_a[i] = b->adapt_pred_order[i];
                else
                    c->nsamples_part_a[i] = b->highest_pred_order;
            } else {
                c->bitalloc_part_a[i] = 0;
                c->nsamples_part_a[i] = 0;
            }

            // Unpack coding parameter for part B of segment
            c->bitalloc_part_b[i] = get_bits(&s->gb, c->nabits);

            // Adjust for the linear code
            if (!c->rice_code_flag[i] && c->bitalloc_part_b[i])
                c->bitalloc_part_b[i]++;
        }
    }

    // Unpack entropy codes
    for (i = 0; i < c->nchannels; i++) {
        int32_t *part_a, *part_b;
        int nsamples_part_b;

        // Select index of coding parameters
        k = c->seg_common ? 0 : i;

        // Slice the segment into parts A and B
        part_a = b->msb_sample_buffer[i] + seg * s->nsegsamples;
        part_b = part_a + c->nsamples_part_a[k];
        nsamples_part_b = s->nsegsamples - c->nsamples_part_a[k];

        if (get_bits_left(&s->gb) < 0)
            return AVERROR_INVALIDDATA;

        if (!c->rice_code_flag[k]) {
            // Linear codes
            // Unpack all residuals of part A of segment 0
            get_linear_array(&s->gb, part_a, c->nsamples_part_a[k],
                             c->bitalloc_part_a[k]);

            // Unpack all residuals of part B of segment 0 and others
            get_linear_array(&s->gb, part_b, nsamples_part_b,
                             c->bitalloc_part_b[k]);
        } else {
            // Rice codes
            // Unpack all residuals of part A of segment 0
            get_rice_array(&s->gb, part_a, c->nsamples_part_a[k],
                           c->bitalloc_part_a[k]);

            if (c->bitalloc_hybrid_linear[k]) {
                // Hybrid Rice codes
                // Unpack the number of isolated samples
                int nisosamples = get_bits(&s->gb, s->nsegsamples_log2);

                // Set all locations to 0
                memset(part_b, 0, sizeof(*part_b) * nsamples_part_b);

                // Extract the locations of isolated samples and flag by -1
                for (j = 0; j < nisosamples; j++) {
                    int loc = get_bits(&s->gb, s->nsegsamples_log2);
                    if (loc >= nsamples_part_b) {
                        av_log(s->avctx, AV_LOG_ERROR, "Invalid isolated sample location\n");
                        return AVERROR_INVALIDDATA;
                    }
                    part_b[loc] = -1;
                }

                // Unpack all residuals of part B of segment 0 and others
                for (j = 0; j < nsamples_part_b; j++) {
                    if (part_b[j])
                        part_b[j] = get_linear(&s->gb, c->bitalloc_hybrid_linear[k]);
                    else
                        part_b[j] = get_rice(&s->gb, c->bitalloc_part_b[k]);
                }
            } else {
                // Rice codes
                // Unpack all residuals of part B of segment 0 and others
                get_rice_array(&s->gb, part_b, nsamples_part_b, c->bitalloc_part_b[k]);
            }
        }
    }

    // Unpack decimator history for frequency band 1
    if (seg == 0 && band == 1) {
        int nbits = get_bits(&s->gb, 5) + 1;
        for (i = 0; i < c->nchannels; i++)
            for (j = 1; j < DCA_XLL_DECI_HISTORY_MAX; j++)
                c->deci_history[i][j] = get_sbits_long(&s->gb, nbits);
    }

    // Start unpacking LSB portion of the segment
    if (b->lsb_section_size) {
        // Skip to the start of LSB portion
        if (ff_dca_seek_bits(&s->gb, band_data_end - b->lsb_section_size * 8)) {
            av_log(s->avctx, AV_LOG_ERROR, "Read past end of XLL band data\n");
            return AVERROR_INVALIDDATA;
        }

        // Unpack all LSB parts of residuals of this segment
        for (i = 0; i < c->nchannels; i++) {
            if (b->nscalablelsbs[i]) {
                get_array(&s->gb,
                          b->lsb_sample_buffer[i] + seg * s->nsegsamples,
                          s->nsegsamples, b->nscalablelsbs[i]);
            }
        }
    }

    // Skip to the end of band data
    if (ff_dca_seek_bits(&s->gb, band_data_end)) {
        av_log(s->avctx, AV_LOG_ERROR, "Read past end of XLL band data\n");
        return AVERROR_INVALIDDATA;
    }

    return 0;
}

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static av_cold void chs_clear_band_data(DCAXllDecoder *s, DCAXllChSet *c, int band, int seg)
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{
    DCAXllBand *b = &c->bands[band];
    int i, offset, nsamples;

    if (seg < 0) {
        offset = 0;
        nsamples = s->nframesamples;
    } else {
        offset = seg * s->nsegsamples;
        nsamples = s->nsegsamples;
    }

    for (i = 0; i < c->nchannels; i++) {
        memset(b->msb_sample_buffer[i] + offset, 0, nsamples * sizeof(int32_t));
        if (b->lsb_section_size)
            memset(b->lsb_sample_buffer[i] + offset, 0, nsamples * sizeof(int32_t));
    }

    if (seg <= 0 && band)
        memset(c->deci_history, 0, sizeof(c->deci_history));

    if (seg < 0) {
        memset(b->nscalablelsbs, 0, sizeof(b->nscalablelsbs));
        memset(b->bit_width_adjust, 0, sizeof(b->bit_width_adjust));
    }
}

static void chs_filter_band_data(DCAXllDecoder *s, DCAXllChSet *c, int band)
{
    DCAXllBand *b = &c->bands[band];
    int nsamples = s->nframesamples;
    int i, j, k;

    // Inverse adaptive or fixed prediction
    for (i = 0; i < c->nchannels; i++) {
        int32_t *buf = b->msb_sample_buffer[i];
        int order = b->adapt_pred_order[i];
        if (order > 0) {
            int coeff[DCA_XLL_ADAPT_PRED_ORDER_MAX];
            // Conversion from reflection coefficients to direct form coefficients
            for (j = 0; j < order; j++) {
                int rc = b->adapt_refl_coeff[i][j];
                for (k = 0; k < (j + 1) / 2; k++) {
                    int tmp1 = coeff[    k    ];
                    int tmp2 = coeff[j - k - 1];
                    coeff[    k    ] = tmp1 + mul16(rc, tmp2);
                    coeff[j - k - 1] = tmp2 + mul16(rc, tmp1);
                }
                coeff[j] = rc;
            }
            // Inverse adaptive prediction
            for (j = 0; j < nsamples - order; j++) {
                int64_t err = 0;
                for (k = 0; k < order; k++)
                    err += (int64_t)buf[j + k] * coeff[order - k - 1];
                buf[j + k] -= clip23(norm16(err));
            }
        } else {
            // Inverse fixed coefficient prediction
            for (j = 0; j < b->fixed_pred_order[i]; j++)
                for (k = 1; k < nsamples; k++)
                    buf[k] += buf[k - 1];
        }
    }

    // Inverse pairwise channel decorrellation
    if (b->decor_enabled) {
        int32_t *tmp[DCA_XLL_CHANNELS_MAX];

        for (i = 0; i < c->nchannels / 2; i++) {
            int coeff = b->decor_coeff[i];
            if (coeff) {
                s->dcadsp->decor(b->msb_sample_buffer[i * 2 + 1],
                                 b->msb_sample_buffer[i * 2    ],
                                 coeff, nsamples);
            }
        }

        // Reorder channel pointers to the original order
        for (i = 0; i < c->nchannels; i++)
            tmp[i] = b->msb_sample_buffer[i];

        for (i = 0; i < c->nchannels; i++)
            b->msb_sample_buffer[b->orig_order[i]] = tmp[i];
    }

    // Map output channel pointers for frequency band 0
    if (c->nfreqbands == 1)
        for (i = 0; i < c->nchannels; i++)
            s->output_samples[c->ch_remap[i]] = b->msb_sample_buffer[i];
}

static int chs_get_lsb_width(DCAXllDecoder *s, DCAXllChSet *c, int band, int ch)
{
    int adj = c->bands[band].bit_width_adjust[ch];
    int shift = c->bands[band].nscalablelsbs[ch];

    if (s->fixed_lsb_width)
        shift = s->fixed_lsb_width;
    else if (shift && adj)
        shift += adj - 1;
    else
        shift += adj;

    return shift;
}

static void chs_assemble_msbs_lsbs(DCAXllDecoder *s, DCAXllChSet *c, int band)
{
    DCAXllBand *b = &c->bands[band];
    int n, ch, nsamples = s->nframesamples;

    for (ch = 0; ch < c->nchannels; ch++) {
        int shift = chs_get_lsb_width(s, c, band, ch);
        if (shift) {
            int32_t *msb = b->msb_sample_buffer[ch];
            if (b->nscalablelsbs[ch]) {
                int32_t *lsb = b->lsb_sample_buffer[ch];
                int adj = b->bit_width_adjust[ch];
                for (n = 0; n < nsamples; n++)
                    msb[n] = msb[n] * (1 << shift) + (lsb[n] << adj);
            } else {
                for (n = 0; n < nsamples; n++)
                    msb[n] = msb[n] * (1 << shift);
            }
        }
    }
}

static int chs_assemble_freq_bands(DCAXllDecoder *s, DCAXllChSet *c)
{
    int ch, nsamples = s->nframesamples;
    int32_t *ptr;

    av_assert1(c->nfreqbands > 1);

    // Reallocate frequency band assembly buffer
    av_fast_malloc(&c->sample_buffer[2], &c->sample_size[2],
                   2 * nsamples * c->nchannels * sizeof(int32_t));
    if (!c->sample_buffer[2])
        return AVERROR(ENOMEM);

    // Assemble frequency bands 0 and 1
    ptr = c->sample_buffer[2];
    for (ch = 0; ch < c->nchannels; ch++) {
        int32_t *band0 = c->bands[0].msb_sample_buffer[ch];
        int32_t *band1 = c->bands[1].msb_sample_buffer[ch];

        // Copy decimator history
        memcpy(band0 - DCA_XLL_DECI_HISTORY_MAX,
               c->deci_history[ch], sizeof(c->deci_history[0]));

        // Filter
        s->dcadsp->assemble_freq_bands(ptr, band0, band1,
                                       ff_dca_xll_band_coeff,
                                       nsamples);

        // Remap output channel pointer to assembly buffer
        s->output_samples[c->ch_remap[ch]] = ptr;
        ptr += nsamples * 2;
    }

    return 0;
}

static int parse_common_header(DCAXllDecoder *s)
{
    int stream_ver, header_size, frame_size_nbits, nframesegs_log2;

    // XLL extension sync word
    if (get_bits_long(&s->gb, 32) != DCA_SYNCWORD_XLL) {
        av_log(s->avctx, AV_LOG_VERBOSE, "Invalid XLL sync word\n");
        return AVERROR(EAGAIN);
    }

    // Version number
    stream_ver = get_bits(&s->gb, 4) + 1;
    if (stream_ver > 1) {
        avpriv_request_sample(s->avctx, "XLL stream version %d", stream_ver);
        return AVERROR_PATCHWELCOME;
    }

    // Lossless frame header length
    header_size = get_bits(&s->gb, 8) + 1;

    // Check CRC
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    if (ff_dca_check_crc(s->avctx, &s->gb, 32, header_size * 8)) {
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        av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL common header checksum\n");
        return AVERROR_INVALIDDATA;
    }

    // Number of bits used to read frame size
    frame_size_nbits = get_bits(&s->gb, 5) + 1;

    // Number of bytes in a lossless frame
    s->frame_size = get_bits_long(&s->gb, frame_size_nbits);
    if (s->frame_size < 0 || s->frame_size >= DCA_XLL_PBR_BUFFER_MAX) {
        av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL frame size (%d bytes)\n", s->frame_size);
        return AVERROR_INVALIDDATA;
    }
    s->frame_size++;

    // Number of channels sets per frame
    s->nchsets = get_bits(&s->gb, 4) + 1;
    if (s->nchsets > DCA_XLL_CHSETS_MAX) {
        avpriv_request_sample(s->avctx, "%d XLL channel sets", s->nchsets);
        return AVERROR_PATCHWELCOME;
    }

    // Number of segments per frame
    nframesegs_log2 = get_bits(&s->gb, 4);
    s->nframesegs = 1 << nframesegs_log2;
    if (s->nframesegs > 1024) {
        av_log(s->avctx, AV_LOG_ERROR, "Too many segments per XLL frame\n");
        return AVERROR_INVALIDDATA;
    }

    // Samples in segment per one frequency band for the first channel set
    // Maximum value is 256 for sampling frequencies <= 48 kHz
    // Maximum value is 512 for sampling frequencies > 48 kHz
    s->nsegsamples_log2 = get_bits(&s->gb, 4);
    if (!s->nsegsamples_log2) {
        av_log(s->avctx, AV_LOG_ERROR, "Too few samples per XLL segment\n");
        return AVERROR_INVALIDDATA;
    }
    s->nsegsamples = 1 << s->nsegsamples_log2;
    if (s->nsegsamples > 512) {
        av_log(s->avctx, AV_LOG_ERROR, "Too many samples per XLL segment\n");
        return AVERROR_INVALIDDATA;
    }

    // Samples in frame per one frequency band for the first channel set
    s->nframesamples_log2 = s->nsegsamples_log2 + nframesegs_log2;
    s->nframesamples = 1 << s->nframesamples_log2;
    if (s->nframesamples > 65536) {
        av_log(s->avctx, AV_LOG_ERROR, "Too many samples per XLL frame\n");
        return AVERROR_INVALIDDATA;
    }

    // Number of bits used to read segment size
    s->seg_size_nbits = get_bits(&s->gb, 5) + 1;

    // Presence of CRC16 within each frequency band
    // 0 - No CRC16 within band
    // 1 - CRC16 placed at the end of MSB0
    // 2 - CRC16 placed at the end of MSB0 and LSB0
    // 3 - CRC16 placed at the end of MSB0 and LSB0 and other frequency bands
    s->band_crc_present = get_bits(&s->gb, 2);

    // MSB/LSB split flag
    s->scalable_lsbs = get_bits1(&s->gb);

    // Channel position mask
    s->ch_mask_nbits = get_bits(&s->gb, 5) + 1;

    // Fixed LSB width
    if (s->scalable_lsbs)
        s->fixed_lsb_width = get_bits(&s->gb, 4);
    else
        s->fixed_lsb_width = 0;

    // Reserved
    // Byte align
    // Header CRC16 protection
    if (ff_dca_seek_bits(&s->gb, header_size * 8)) {
        av_log(s->avctx, AV_LOG_ERROR, "Read past end of XLL common header\n");
        return AVERROR_INVALIDDATA;
    }

    return 0;
}

static int is_hier_dmix_chset(DCAXllChSet *c)
{
    return !c->primary_chset && c->dmix_embedded && c->hier_chset;
}

static DCAXllChSet *find_next_hier_dmix_chset(DCAXllDecoder *s, DCAXllChSet *c)
{
    if (c->hier_chset)
        while (++c < &s->chset[s->nchsets])
            if (is_hier_dmix_chset(c))
                return c;

    return NULL;
}

static void prescale_down_mix(DCAXllChSet *c, DCAXllChSet *o)
{
    int i, j, *coeff_ptr = c->dmix_coeff;

    for (i = 0; i < c->hier_ofs; i++) {
        int scale = o->dmix_scale[i];
        int scale_inv = o->dmix_scale_inv[i];
        c->dmix_scale[i] = mul15(c->dmix_scale[i], scale);
        c->dmix_scale_inv[i] = mul16(c->dmix_scale_inv[i], scale_inv);
        for (j = 0; j < c->nchannels; j++) {
            int coeff = mul16(*coeff_ptr, scale_inv);
            *coeff_ptr++ = mul15(coeff, o->dmix_scale[c->hier_ofs + j]);
        }
    }
}

static int parse_sub_headers(DCAXllDecoder *s, DCAExssAsset *asset)
{
    DCAContext *dca = s->avctx->priv_data;
    DCAXllChSet *c;
    int i, ret;

    // Parse channel set headers
    s->nfreqbands = 0;
    s->nchannels = 0;
    s->nreschsets = 0;
    for (i = 0, c = s->chset; i < s->nchsets; i++, c++) {
        c->hier_ofs = s->nchannels;
        if ((ret = chs_parse_header(s, c, asset)) < 0)
            return ret;
        if (c->nfreqbands > s->nfreqbands)
            s->nfreqbands = c->nfreqbands;
        if (c->hier_chset)
            s->nchannels += c->nchannels;
        if (c->residual_encode != (1 << c->nchannels) - 1)
            s->nreschsets++;
    }

    // Pre-scale downmixing coefficients for all non-primary channel sets
    for (i = s->nchsets - 1, c = &s->chset[i]; i > 0; i--, c--) {
        if (is_hier_dmix_chset(c)) {
            DCAXllChSet *o = find_next_hier_dmix_chset(s, c);
            if (o)
                prescale_down_mix(c, o);
        }
    }

    // Determine number of active channel sets to decode
    switch (dca->request_channel_layout) {
    case DCA_SPEAKER_LAYOUT_STEREO:
        s->nactivechsets = 1;
        break;
    case DCA_SPEAKER_LAYOUT_5POINT0:
    case DCA_SPEAKER_LAYOUT_5POINT1:
        s->nactivechsets = (s->chset[0].nchannels < 5 && s->nchsets > 1) ? 2 : 1;
        break;
    default:
        s->nactivechsets = s->nchsets;
        break;
    }

    return 0;
}

static int parse_navi_table(DCAXllDecoder *s)
{
    int chs, seg, band, navi_nb, navi_pos, *navi_ptr;
    DCAXllChSet *c;

    // Determine size of NAVI table
    navi_nb = s->nfreqbands * s->nframesegs * s->nchsets;
    if (navi_nb > 1024) {
        av_log(s->avctx, AV_LOG_ERROR, "Too many NAVI entries (%d)\n", navi_nb);
        return AVERROR_INVALIDDATA;
    }

    // Reallocate NAVI table
    av_fast_malloc(&s->navi, &s->navi_size, navi_nb * sizeof(*s->navi));
    if (!s->navi)
        return AVERROR(ENOMEM);

    // Parse NAVI
    navi_pos = get_bits_count(&s->gb);
    navi_ptr = s->navi;
    for (band = 0; band < s->nfreqbands; band++) {
        for (seg = 0; seg < s->nframesegs; seg++) {
            for (chs = 0, c = s->chset; chs < s->nchsets; chs++, c++) {
                int size = 0;
                if (c->nfreqbands > band) {
                    size = get_bits_long(&s->gb, s->seg_size_nbits);
                    if (size < 0 || size >= s->frame_size) {
                        av_log(s->avctx, AV_LOG_ERROR, "Invalid NAVI segment size (%d bytes)\n", size);
                        return AVERROR_INVALIDDATA;
                    }
                    size++;
                }
                *navi_ptr++ = size;
            }
        }
    }

    // Byte align
    // CRC16
    skip_bits(&s->gb, -get_bits_count(&s->gb) & 7);
    skip_bits(&s->gb, 16);

    // Check CRC
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    if (ff_dca_check_crc(s->avctx, &s->gb, navi_pos, get_bits_count(&s->gb))) {
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        av_log(s->avctx, AV_LOG_ERROR, "Invalid NAVI checksum\n");
        return AVERROR_INVALIDDATA;
    }

    return 0;
}

static int parse_band_data(DCAXllDecoder *s)
{
    int ret, chs, seg, band, navi_pos, *navi_ptr;
    DCAXllChSet *c;

    for (chs = 0, c = s->chset; chs < s->nactivechsets; chs++, c++) {
        if ((ret = chs_alloc_msb_band_data(s, c)) < 0)
            return ret;
        if ((ret = chs_alloc_lsb_band_data(s, c)) < 0)
            return ret;
    }

    navi_pos = get_bits_count(&s->gb);
    navi_ptr = s->navi;
    for (band = 0; band < s->nfreqbands; band++) {
        for (seg = 0; seg < s->nframesegs; seg++) {
            for (chs = 0, c = s->chset; chs < s->nchsets; chs++, c++) {
                if (c->nfreqbands > band) {
                    navi_pos += *navi_ptr * 8;
                    if (navi_pos > s->gb.size_in_bits) {
                        av_log(s->avctx, AV_LOG_ERROR, "Invalid NAVI position\n");
                        return AVERROR_INVALIDDATA;
                    }
                    if (chs < s->nactivechsets &&
                        (ret = chs_parse_band_data(s, c, band, seg, navi_pos)) < 0) {
                        if (s->avctx->err_recognition & AV_EF_EXPLODE)
                            return ret;
                        chs_clear_band_data(s, c, band, seg);
                    }
                    s->gb.index = navi_pos;
                }
                navi_ptr++;
            }
        }
    }

    return 0;
}

static int parse_frame(DCAXllDecoder *s, uint8_t *data, int size, DCAExssAsset *asset)
{
    int ret;

    if ((ret = init_get_bits8(&s->gb, data, size)) < 0)
        return ret;
    if ((ret = parse_common_header(s)) < 0)
        return ret;
    if ((ret = parse_sub_headers(s, asset)) < 0)
        return ret;
    if ((ret = parse_navi_table(s)) < 0)
        return ret;
    if ((ret = parse_band_data(s)) < 0)
        return ret;
    if (ff_dca_seek_bits(&s->gb, s->frame_size * 8)) {
        av_log(s->avctx, AV_LOG_ERROR, "Read past end of XLL frame\n");
        return AVERROR_INVALIDDATA;
    }
    return ret;
}

static void clear_pbr(DCAXllDecoder *s)
{
    s->pbr_length = 0;
    s->pbr_delay = 0;
}

static int copy_to_pbr(DCAXllDecoder *s, uint8_t *data, int size, int delay)
{
    if (size > DCA_XLL_PBR_BUFFER_MAX)
        return AVERROR(ENOSPC);

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    if (!s->pbr_buffer && !(s->pbr_buffer = av_malloc(DCA_XLL_PBR_BUFFER_MAX + AV_INPUT_BUFFER_PADDING_SIZE)))
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        return AVERROR(ENOMEM);

    memcpy(s->pbr_buffer, data, size);
    s->pbr_length = size;
    s->pbr_delay = delay;
    return 0;
}

static int parse_frame_no_pbr(DCAXllDecoder *s, uint8_t *data, int size, DCAExssAsset *asset)
{
    int ret = parse_frame(s, data, size, asset);

    // If XLL packet data didn't start with a sync word, we must have jumped
    // right into the middle of PBR smoothing period
    if (ret == AVERROR(EAGAIN) && asset->xll_sync_present && asset->xll_sync_offset < size) {
        // Skip to the next sync word in this packet
        data += asset->xll_sync_offset;
        size -= asset->xll_sync_offset;

        // If decoding delay is set, put the frame into PBR buffer and return
        // failure code. Higher level decoder is expected to switch to lossy
        // core decoding or mute its output until decoding delay expires.
        if (asset->xll_delay_nframes > 0) {
            if ((ret = copy_to_pbr(s, data, size, asset->xll_delay_nframes)) < 0)
                return ret;
            return AVERROR(EAGAIN);
        }

        // No decoding delay, just parse the frame in place
        ret = parse_frame(s, data, size, asset);
    }

    if (ret < 0)
        return ret;

    if (s->frame_size > size)
        return AVERROR(EINVAL);

    // If the XLL decoder didn't consume full packet, start PBR smoothing period
    if (s->frame_size < size)
        if ((ret = copy_to_pbr(s, data + s->frame_size, size - s->frame_size, 0)) < 0)
            return ret;

    return 0;
}

static int parse_frame_pbr(DCAXllDecoder *s, uint8_t *data, int size, DCAExssAsset *asset)
{
    int ret;

    if (size > DCA_XLL_PBR_BUFFER_MAX - s->pbr_length) {
        ret = AVERROR(ENOSPC);
        goto fail;
    }

    memcpy(s->pbr_buffer + s->pbr_length, data, size);
    s->pbr_length += size;

    // Respect decoding delay after synchronization error
    if (s->pbr_delay > 0 && --s->pbr_delay)
        return AVERROR(EAGAIN);

    if ((ret = parse_frame(s, s->pbr_buffer, s->pbr_length, asset)) < 0)
        goto fail;

    if (s->frame_size > s->pbr_length) {
        ret = AVERROR(EINVAL);
        goto fail;
    }

    if (s->frame_size == s->pbr_length) {
        // End of PBR smoothing period
        clear_pbr(s);
    } else {
        s->pbr_length -= s->frame_size;
        memmove(s->pbr_buffer, s->pbr_buffer + s->frame_size, s->pbr_length);
    }

    return 0;

fail:
    // For now, throw out all PBR state on failure.
    // Perhaps we can be smarter and try to resync somehow.
    clear_pbr(s);
    return ret;
}

int ff_dca_xll_parse(DCAXllDecoder *s, uint8_t *data, DCAExssAsset *asset)
{
    int ret;

    if (s->hd_stream_id != asset->hd_stream_id) {
        clear_pbr(s);
        s->hd_stream_id = asset->hd_stream_id;
    }

    if (s->pbr_length)
        ret = parse_frame_pbr(s, data + asset->xll_offset, asset->xll_size, asset);
    else
        ret = parse_frame_no_pbr(s, data + asset->xll_offset, asset->xll_size, asset);

    return ret;
}

static void undo_down_mix(DCAXllDecoder *s, DCAXllChSet *o, int band)
{
    int i, j, k, nchannels = 0, *coeff_ptr = o->dmix_coeff;
    DCAXllChSet *c;

    for (i = 0, c = s->chset; i < s->nactivechsets; i++, c++) {
        if (!c->hier_chset)
            continue;

        av_assert1(band < c->nfreqbands);
        for (j = 0; j < c->nchannels; j++) {
            for (k = 0; k < o->nchannels; k++) {
                int coeff = *coeff_ptr++;
                if (coeff) {
                    s->dcadsp->dmix_sub(c->bands[band].msb_sample_buffer[j],
                                        o->bands[band].msb_sample_buffer[k],
                                        coeff, s->nframesamples);
                    if (band)
                        s->dcadsp->dmix_sub(c->deci_history[j],
                                            o->deci_history[k],
                                            coeff, DCA_XLL_DECI_HISTORY_MAX);
                }
            }
        }

        nchannels += c->nchannels;
        if (nchannels >= o->hier_ofs)
            break;
    }
}

static void scale_down_mix(DCAXllDecoder *s, DCAXllChSet *o, int band)
{
    int i, j, nchannels = 0;
    DCAXllChSet *c;

    for (i = 0, c = s->chset; i < s->nactivechsets; i++, c++) {
        if (!c->hier_chset)
            continue;

        av_assert1(band < c->nfreqbands);
        for (j = 0; j < c->nchannels; j++) {
            int scale = o->dmix_scale[nchannels++];
            if (scale != (1 << 15)) {
                s->dcadsp->dmix_scale(c->bands[band].msb_sample_buffer[j],
                                      scale, s->nframesamples);
                if (band)
                    s->dcadsp->dmix_scale(c->deci_history[j],
                                          scale, DCA_XLL_DECI_HISTORY_MAX);
            }
        }

        if (nchannels >= o->hier_ofs)
            break;
    }
}

// Clear all band data and replace non-residual encoded channels with lossy
// counterparts
1237
static av_cold void force_lossy_output(DCAXllDecoder *s, DCAXllChSet *c)
1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417
{
    DCAContext *dca = s->avctx->priv_data;
    int band, ch;

    for (band = 0; band < c->nfreqbands; band++)
        chs_clear_band_data(s, c, band, -1);

    for (ch = 0; ch < c->nchannels; ch++) {
        if (!(c->residual_encode & (1 << ch)))
            continue;
        if (ff_dca_core_map_spkr(&dca->core, c->ch_remap[ch]) < 0)
            continue;
        c->residual_encode &= ~(1 << ch);
    }
}

static int combine_residual_frame(DCAXllDecoder *s, DCAXllChSet *c)
{
    DCAContext *dca = s->avctx->priv_data;
    int ch, nsamples = s->nframesamples;
    DCAXllChSet *o;

    // Verify that core is compatible
    if (!(dca->packet & DCA_PACKET_CORE)) {
        av_log(s->avctx, AV_LOG_ERROR, "Residual encoded channels are present without core\n");
        return AVERROR(EINVAL);
    }

    if (c->freq != dca->core.output_rate) {
        av_log(s->avctx, AV_LOG_WARNING, "Sample rate mismatch between core (%d Hz) and XLL (%d Hz)\n", dca->core.output_rate, c->freq);
        return AVERROR_INVALIDDATA;
    }

    if (nsamples != dca->core.npcmsamples) {
        av_log(s->avctx, AV_LOG_WARNING, "Number of samples per frame mismatch between core (%d) and XLL (%d)\n", dca->core.npcmsamples, nsamples);
        return AVERROR_INVALIDDATA;
    }

    // See if this channel set is downmixed and find the next channel set in
    // hierarchy. If downmixed, undo core pre-scaling before combining with
    // residual (residual is not scaled).
    o = find_next_hier_dmix_chset(s, c);

    // Reduce core bit width and combine with residual
    for (ch = 0; ch < c->nchannels; ch++) {
        int n, spkr, shift, round;
        int32_t *src, *dst;

        if (c->residual_encode & (1 << ch))
            continue;

        // Map this channel to core speaker
        spkr = ff_dca_core_map_spkr(&dca->core, c->ch_remap[ch]);
        if (spkr < 0) {
            av_log(s->avctx, AV_LOG_WARNING, "Residual encoded channel (%d) references unavailable core channel\n", c->ch_remap[ch]);
            return AVERROR_INVALIDDATA;
        }

        // Account for LSB width
        shift = 24 - c->pcm_bit_res + chs_get_lsb_width(s, c, 0, ch);
        if (shift > 24) {
            av_log(s->avctx, AV_LOG_WARNING, "Invalid core shift (%d bits)\n", shift);
            return AVERROR_INVALIDDATA;
        }

        round = shift > 0 ? 1 << (shift - 1) : 0;

        src = dca->core.output_samples[spkr];
        dst = c->bands[0].msb_sample_buffer[ch];
        if (o) {
            // Undo embedded core downmix pre-scaling
            int scale_inv = o->dmix_scale_inv[c->hier_ofs + ch];
            for (n = 0; n < nsamples; n++)
                dst[n] += clip23((mul16(src[n], scale_inv) + round) >> shift);
        } else {
            // No downmix scaling
            for (n = 0; n < nsamples; n++)
                dst[n] += (src[n] + round) >> shift;
        }
    }

    return 0;
}

int ff_dca_xll_filter_frame(DCAXllDecoder *s, AVFrame *frame)
{
    AVCodecContext *avctx = s->avctx;
    DCAContext *dca = avctx->priv_data;
    DCAExssAsset *asset = &dca->exss.assets[0];
    DCAXllChSet *p = &s->chset[0], *c;
    enum AVMatrixEncoding matrix_encoding = AV_MATRIX_ENCODING_NONE;
    int i, j, k, ret, shift, nsamples, request_mask;
    int ch_remap[DCA_SPEAKER_COUNT];

    // Force lossy downmixed output during recovery
    if (dca->packet & DCA_PACKET_RECOVERY) {
        for (i = 0, c = s->chset; i < s->nchsets; i++, c++) {
            if (i < s->nactivechsets)
                force_lossy_output(s, c);

            if (!c->primary_chset)
                c->dmix_embedded = 0;
        }

        s->scalable_lsbs = 0;
        s->fixed_lsb_width = 0;
    }

    // Filter frequency bands for active channel sets
    s->output_mask = 0;
    for (i = 0, c = s->chset; i < s->nactivechsets; i++, c++) {
        chs_filter_band_data(s, c, 0);

        if (c->residual_encode != (1 << c->nchannels) - 1
            && (ret = combine_residual_frame(s, c)) < 0)
            return ret;

        if (s->scalable_lsbs)
            chs_assemble_msbs_lsbs(s, c, 0);

        if (c->nfreqbands > 1) {
            chs_filter_band_data(s, c, 1);
            chs_assemble_msbs_lsbs(s, c, 1);
        }

        s->output_mask |= c->ch_mask;
    }

    // Undo hierarchial downmix and/or apply scaling
    for (i = 1, c = &s->chset[1]; i < s->nchsets; i++, c++) {
        if (!is_hier_dmix_chset(c))
            continue;

        if (i >= s->nactivechsets) {
            for (j = 0; j < c->nfreqbands; j++)
                if (c->bands[j].dmix_embedded)
                    scale_down_mix(s, c, j);
            break;
        }

        for (j = 0; j < c->nfreqbands; j++)
            if (c->bands[j].dmix_embedded)
                undo_down_mix(s, c, j);
    }

    // Assemble frequency bands for active channel sets
    if (s->nfreqbands > 1) {
        for (i = 0; i < s->nactivechsets; i++)
            if ((ret = chs_assemble_freq_bands(s, &s->chset[i])) < 0)
                return ret;
    }

    // Normalize to regular 5.1 layout if downmixing
    if (dca->request_channel_layout) {
        if (s->output_mask & DCA_SPEAKER_MASK_Lss) {
            s->output_samples[DCA_SPEAKER_Ls] = s->output_samples[DCA_SPEAKER_Lss];
            s->output_mask = (s->output_mask & ~DCA_SPEAKER_MASK_Lss) | DCA_SPEAKER_MASK_Ls;
        }
        if (s->output_mask & DCA_SPEAKER_MASK_Rss) {
            s->output_samples[DCA_SPEAKER_Rs] = s->output_samples[DCA_SPEAKER_Rss];
            s->output_mask = (s->output_mask & ~DCA_SPEAKER_MASK_Rss) | DCA_SPEAKER_MASK_Rs;
        }
    }

    // Handle downmixing to stereo request
    if (dca->request_channel_layout == DCA_SPEAKER_LAYOUT_STEREO
        && DCA_HAS_STEREO(s->output_mask) && p->dmix_embedded
        && (p->dmix_type == DCA_DMIX_TYPE_LoRo ||
            p->dmix_type == DCA_DMIX_TYPE_LtRt))
        request_mask = DCA_SPEAKER_LAYOUT_STEREO;
    else
        request_mask = s->output_mask;
    if (!ff_dca_set_channel_layout(avctx, ch_remap, request_mask))
        return AVERROR(EINVAL);

    avctx->sample_rate = p->freq << (s->nfreqbands - 1);

    switch (p->storage_bit_res) {
    case 16:
        avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
1418
        shift = 16 - p->pcm_bit_res;
1419
        break;
1420
    case 20:
1421 1422
    case 24:
        avctx->sample_fmt = AV_SAMPLE_FMT_S32P;
1423
        shift = 24 - p->pcm_bit_res;
1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493
        break;
    default:
        return AVERROR(EINVAL);
    }

    avctx->bits_per_raw_sample = p->storage_bit_res;
    avctx->profile = FF_PROFILE_DTS_HD_MA;
    avctx->bit_rate = 0;

    frame->nb_samples = nsamples = s->nframesamples << (s->nfreqbands - 1);
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
        return ret;

    // Downmix primary channel set to stereo
    if (request_mask != s->output_mask) {
        ff_dca_downmix_to_stereo_fixed(s->dcadsp, s->output_samples,
                                       p->dmix_coeff, nsamples,
                                       s->output_mask);
    }

    for (i = 0; i < avctx->channels; i++) {
        int32_t *samples = s->output_samples[ch_remap[i]];
        if (frame->format == AV_SAMPLE_FMT_S16P) {
            int16_t *plane = (int16_t *)frame->extended_data[i];
            for (k = 0; k < nsamples; k++)
                plane[k] = av_clip_int16(samples[k] * (1 << shift));
        } else {
            int32_t *plane = (int32_t *)frame->extended_data[i];
            for (k = 0; k < nsamples; k++)
                plane[k] = clip23(samples[k] * (1 << shift)) * (1 << 8);
        }
    }

    if (!asset->one_to_one_map_ch_to_spkr) {
        if (asset->representation_type == DCA_REPR_TYPE_LtRt)
            matrix_encoding = AV_MATRIX_ENCODING_DOLBY;
        else if (asset->representation_type == DCA_REPR_TYPE_LhRh)
            matrix_encoding = AV_MATRIX_ENCODING_DOLBYHEADPHONE;
    } else if (request_mask != s->output_mask && p->dmix_type == DCA_DMIX_TYPE_LtRt) {
        matrix_encoding = AV_MATRIX_ENCODING_DOLBY;
    }
    if ((ret = ff_side_data_update_matrix_encoding(frame, matrix_encoding)) < 0)
        return ret;

    return 0;
}

av_cold void ff_dca_xll_flush(DCAXllDecoder *s)
{
    clear_pbr(s);
}

av_cold void ff_dca_xll_close(DCAXllDecoder *s)
{
    DCAXllChSet *c;
    int i, j;

    for (i = 0, c = s->chset; i < DCA_XLL_CHSETS_MAX; i++, c++) {
        for (j = 0; j < DCA_XLL_SAMPLE_BUFFERS_MAX; j++) {
            av_freep(&c->sample_buffer[j]);
            c->sample_size[j] = 0;
        }
    }

    av_freep(&s->navi);
    s->navi_size = 0;

    av_freep(&s->pbr_buffer);
    clear_pbr(s);
}