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/*

 * Copyright (c) 2010-2011 Maxim Poliakovski

 * Copyright (c) 2010-2011 Elvis Presley

 *

 * 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

 */

/**

 * @file

 * Known FOURCCs: 'apch' (HQ), 'apcn' (SD), 'apcs' (LT), 'acpo' (Proxy), 'ap4h' (4444)

 */

//#define DEBUG

#define LONG_BITSTREAM_READER

#include "avcodec.h"

#include "get_bits.h"

#include "internal.h"

#include "simple_idct.h"

#include "proresdec.h"

#include "proresdata.h"

static void permute(uint8_t *dst, const uint8_t *src, const uint8_t permutation[64])

{

    int i;

    for (i = 0; i < 64; i++)

        dst[i] = permutation[src[i]];

}

static av_cold int decode_init(AVCodecContext *avctx)

{

    ProresContext *ctx = avctx->priv_data;

    uint8_t idct_permutation[64];

    avctx->bits_per_raw_sample = 10;

    ff_dsputil_init(&ctx->dsp, avctx);

    ff_proresdsp_init(&ctx->prodsp, avctx);

    ff_init_scantable_permutation(idct_permutation,

                                  ctx->prodsp.idct_permutation_type);

    permute(ctx->progressive_scan, ff_prores_progressive_scan, idct_permutation);

    permute(ctx->interlaced_scan, ff_prores_interlaced_scan, idct_permutation);

    return 0;

}

static int decode_frame_header(ProresContext *ctx, const uint8_t *buf,

                               const int data_size, AVCodecContext *avctx)

{

    int hdr_size, width, height, flags;

    int version;

    const uint8_t *ptr;

    hdr_size = AV_RB16(buf);

    av_dlog(avctx, "header size %d\n", hdr_size);

    if (hdr_size > data_size) {

        av_log(avctx, AV_LOG_ERROR, "error, wrong header size\n");

        return AVERROR_INVALIDDATA;

    }

    version = AV_RB16(buf + 2);

    av_dlog(avctx, "%.4s version %d\n", buf+4, version);

    if (version > 1) {

        av_log(avctx, AV_LOG_ERROR, "unsupported version: %d\n", version);

        return AVERROR_PATCHWELCOME;

    }

    width  = AV_RB16(buf + 8);

    height = AV_RB16(buf + 10);

    if (width != avctx->width || height != avctx->height) {

        av_log(avctx, AV_LOG_ERROR, "picture resolution change: %dx%d -> %dx%d\n",

               avctx->width, avctx->height, width, height);

        return AVERROR_PATCHWELCOME;

    }

    ctx->frame_type = (buf[12] >> 2) & 3;

    ctx->alpha_info = buf[17] & 0xf;

    if (ctx->alpha_info > 2) {

        av_log(avctx, AV_LOG_ERROR, "Invalid alpha mode %d\n", ctx->alpha_info);

        return AVERROR_INVALIDDATA;

    }

    if (avctx->skip_alpha) ctx->alpha_info = 0;

    av_dlog(avctx, "frame type %d\n", ctx->frame_type);

    if (ctx->frame_type == 0) {

        ctx->scan = ctx->progressive_scan; // permuted

    } else {

        ctx->scan = ctx->interlaced_scan; // permuted

        ctx->frame->interlaced_frame = 1;

        ctx->frame->top_field_first = ctx->frame_type == 1;

    }

    if (ctx->alpha_info) {

        avctx->pix_fmt = (buf[12] & 0xC0) == 0xC0 ? AV_PIX_FMT_YUVA444P10 : AV_PIX_FMT_YUVA422P10;

    } else {

        avctx->pix_fmt = (buf[12] & 0xC0) == 0xC0 ? AV_PIX_FMT_YUV444P10 : AV_PIX_FMT_YUV422P10;

    }

    ptr   = buf + 20;

    flags = buf[19];

    av_dlog(avctx, "flags %x\n", flags);

    if (flags & 2) {

        if(buf + data_size - ptr < 64) {

            av_log(avctx, AV_LOG_ERROR, "Header truncated\n");

            return AVERROR_INVALIDDATA;

        }

        permute(ctx->qmat_luma, ctx->prodsp.idct_permutation, ptr);

        ptr += 64;

    } else {

        memset(ctx->qmat_luma, 4, 64);

    }

    if (flags & 1) {

        if(buf + data_size - ptr < 64) {

            av_log(avctx, AV_LOG_ERROR, "Header truncated\n");

            return AVERROR_INVALIDDATA;

        }

        permute(ctx->qmat_chroma, ctx->prodsp.idct_permutation, ptr);

    } else {

        memset(ctx->qmat_chroma, 4, 64);

    }

    return hdr_size;

}

static int decode_picture_header(AVCodecContext *avctx, const uint8_t *buf, const int buf_size)

{

    ProresContext *ctx = avctx->priv_data;

    int i, hdr_size, slice_count;

    unsigned pic_data_size;

    int log2_slice_mb_width, log2_slice_mb_height;

    int slice_mb_count, mb_x, mb_y;

    const uint8_t *data_ptr, *index_ptr;

    hdr_size = buf[0] >> 3;

    if (hdr_size < 8 || hdr_size > buf_size) {

        av_log(avctx, AV_LOG_ERROR, "error, wrong picture header size\n");

        return AVERROR_INVALIDDATA;

    }

    pic_data_size = AV_RB32(buf + 1);

    if (pic_data_size > buf_size) {

        av_log(avctx, AV_LOG_ERROR, "error, wrong picture data size\n");

        return AVERROR_INVALIDDATA;

    }

    log2_slice_mb_width  = buf[7] >> 4;

    log2_slice_mb_height = buf[7] & 0xF;

    if (log2_slice_mb_width > 3 || log2_slice_mb_height) {

        av_log(avctx, AV_LOG_ERROR, "unsupported slice resolution: %dx%d\n",

               1 << log2_slice_mb_width, 1 << log2_slice_mb_height);

        return AVERROR_INVALIDDATA;

    }

    ctx->mb_width  = (avctx->width  + 15) >> 4;

    if (ctx->frame_type)

        ctx->mb_height = (avctx->height + 31) >> 5;

    else

        ctx->mb_height = (avctx->height + 15) >> 4;

    slice_count = AV_RB16(buf + 5);

    if (ctx->slice_count != slice_count || !ctx->slices) {

        av_freep(&ctx->slices);

        ctx->slices = av_mallocz(slice_count * sizeof(*ctx->slices));

        if (!ctx->slices)

            return AVERROR(ENOMEM);

        ctx->slice_count = slice_count;

    }

    if (!slice_count)

        return AVERROR(EINVAL);

    if (hdr_size + slice_count*2 > buf_size) {

        av_log(avctx, AV_LOG_ERROR, "error, wrong slice count\n");

        return AVERROR_INVALIDDATA;

    }

    // parse slice information

    index_ptr = buf + hdr_size;

    data_ptr  = index_ptr + slice_count*2;

    slice_mb_count = 1 << log2_slice_mb_width;

    mb_x = 0;

    mb_y = 0;

    for (i = 0; i < slice_count; i++) {

        SliceContext *slice = &ctx->slices[i];

        slice->data = data_ptr;

        data_ptr += AV_RB16(index_ptr + i*2);

        while (ctx->mb_width - mb_x < slice_mb_count)

            slice_mb_count >>= 1;

        slice->mb_x = mb_x;

        slice->mb_y = mb_y;

        slice->mb_count = slice_mb_count;

        slice->data_size = data_ptr - slice->data;

        if (slice->data_size < 6) {

            av_log(avctx, AV_LOG_ERROR, "error, wrong slice data size\n");

            return AVERROR_INVALIDDATA;

        }

        mb_x += slice_mb_count;

        if (mb_x == ctx->mb_width) {

            slice_mb_count = 1 << log2_slice_mb_width;

            mb_x = 0;

            mb_y++;

        }

        if (data_ptr > buf + buf_size) {

            av_log(avctx, AV_LOG_ERROR, "error, slice out of bounds\n");

            return AVERROR_INVALIDDATA;

        }

    }

    if (mb_x || mb_y != ctx->mb_height) {

        av_log(avctx, AV_LOG_ERROR, "error wrong mb count y %d h %d\n",

               mb_y, ctx->mb_height);

        return AVERROR_INVALIDDATA;

    }

    return pic_data_size;

}

#define DECODE_CODEWORD(val, codebook)                                  \

    do {                                                                \

        unsigned int rice_order, exp_order, switch_bits;                \

        unsigned int q, buf, bits;                                      \

                                                                        \

        UPDATE_CACHE(re, gb);                                           \

        buf = GET_CACHE(re, gb);                                        \

                                                                        \

        /* number of bits to switch between rice and exp golomb */      \

        switch_bits =  codebook & 3;                                    \

        rice_order  =  codebook >> 5;                                   \

        exp_order   = (codebook >> 2) & 7;                              \

                                                                        \

        q = 31 - av_log2(buf);                                          \

                                                                        \

        if (q > switch_bits) { /* exp golomb */                         \

            bits = exp_order - switch_bits + (q<<1);                    \

            val = SHOW_UBITS(re, gb, bits) - (1 << exp_order) +         \

                ((switch_bits + 1) << rice_order);                      \

            SKIP_BITS(re, gb, bits);                                    \

        } else if (rice_order) {                                        \

            SKIP_BITS(re, gb, q+1);                                     \

            val = (q << rice_order) + SHOW_UBITS(re, gb, rice_order);   \

            SKIP_BITS(re, gb, rice_order);                              \

        } else {                                                        \

            val = q;                                                    \

            SKIP_BITS(re, gb, q+1);                                     \

        }                                                               \

    } while (0)

#define TOSIGNED(x) (((x) >> 1) ^ (-((x) & 1)))

#define FIRST_DC_CB 0xB8

static const uint8_t dc_codebook[7] = { 0x04, 0x28, 0x28, 0x4D, 0x4D, 0x70, 0x70};

static av_always_inline void decode_dc_coeffs(GetBitContext *gb, int16_t *out,

                                              int blocks_per_slice)

{

    int16_t prev_dc;

    int code, i, sign;

    OPEN_READER(re, gb);

    DECODE_CODEWORD(code, FIRST_DC_CB);

    prev_dc = TOSIGNED(code);

    out[0] = prev_dc;

    out += 64; // dc coeff for the next block

    code = 5;

    sign = 0;

    for (i = 1; i < blocks_per_slice; i++, out += 64) {

        DECODE_CODEWORD(code, dc_codebook[FFMIN(code, 6U)]);

        if(code) sign ^= -(code & 1);

        else     sign  = 0;

        prev_dc += (((code + 1) >> 1) ^ sign) - sign;

        out[0] = prev_dc;

    }

    CLOSE_READER(re, gb);

}

// adaptive codebook switching lut according to previous run/level values

static const uint8_t run_to_cb[16] = { 0x06, 0x06, 0x05, 0x05, 0x04, 0x29, 0x29, 0x29, 0x29, 0x28, 0x28, 0x28, 0x28, 0x28, 0x28, 0x4C };

static const uint8_t lev_to_cb[10] = { 0x04, 0x0A, 0x05, 0x06, 0x04, 0x28, 0x28, 0x28, 0x28, 0x4C };

static av_always_inline int decode_ac_coeffs(AVCodecContext *avctx, GetBitContext *gb,

                                             int16_t *out, int blocks_per_slice)

{

    ProresContext *ctx = avctx->priv_data;

    int block_mask, sign;

    unsigned pos, run, level;

    int max_coeffs, i, bits_left;

    int log2_block_count = av_log2(blocks_per_slice);

    OPEN_READER(re, gb);

    UPDATE_CACHE(re, gb);                                           \

    run   = 4;

    level = 2;

    max_coeffs = 64 << log2_block_count;

    block_mask = blocks_per_slice - 1;

    for (pos = block_mask;;) {

        bits_left = gb->size_in_bits - re_index;

        if (!bits_left || (bits_left < 32 && !SHOW_UBITS(re, gb, bits_left)))

            break;

        DECODE_CODEWORD(run, run_to_cb[FFMIN(run,  15)]);

        pos += run + 1;

        if (pos >= max_coeffs) {

            av_log(avctx, AV_LOG_ERROR, "ac tex damaged %d, %d\n", pos, max_coeffs);

            return AVERROR_INVALIDDATA;

        }

        DECODE_CODEWORD(level, lev_to_cb[FFMIN(level, 9)]);

        level += 1;

        i = pos >> log2_block_count;

        sign = SHOW_SBITS(re, gb, 1);

        SKIP_BITS(re, gb, 1);

        out[((pos & block_mask) << 6) + ctx->scan[i]] = ((level ^ sign) - sign);

    }

    CLOSE_READER(re, gb);

    return 0;

}

static int decode_slice_luma(AVCodecContext *avctx, SliceContext *slice,

                             uint16_t *dst, int dst_stride,

                             const uint8_t *buf, unsigned buf_size,

                             const int16_t *qmat)

{

    ProresContext *ctx = avctx->priv_data;

    LOCAL_ALIGNED_16(int16_t, blocks, [8*4*64]);

    int16_t *block;

    GetBitContext gb;

    int i, blocks_per_slice = slice->mb_count<<2;

    int ret;

    for (i = 0; i < blocks_per_slice; i++)

        ctx->dsp.clear_block(blocks+(i<<6));

    init_get_bits(&gb, buf, buf_size << 3);

    decode_dc_coeffs(&gb, blocks, blocks_per_slice);

    if ((ret = decode_ac_coeffs(avctx, &gb, blocks, blocks_per_slice)) < 0)

        return ret;

    block = blocks;

    for (i = 0; i < slice->mb_count; i++) {

        ctx->prodsp.idct_put(dst, dst_stride, block+(0<<6), qmat);

        ctx->prodsp.idct_put(dst             +8, dst_stride, block+(1<<6), qmat);

        ctx->prodsp.idct_put(dst+4*dst_stride  , dst_stride, block+(2<<6), qmat);

        ctx->prodsp.idct_put(dst+4*dst_stride+8, dst_stride, block+(3<<6), qmat);

        block += 4*64;

        dst += 16;

    }

    return 0;

}

static int decode_slice_chroma(AVCodecContext *avctx, SliceContext *slice,

                               uint16_t *dst, int dst_stride,

                               const uint8_t *buf, unsigned buf_size,

                               const int16_t *qmat, int log2_blocks_per_mb)

{

    ProresContext *ctx = avctx->priv_data;

    LOCAL_ALIGNED_16(int16_t, blocks, [8*4*64]);

    int16_t *block;

    GetBitContext gb;

    int i, j, blocks_per_slice = slice->mb_count << log2_blocks_per_mb;

    int ret;

    for (i = 0; i < blocks_per_slice; i++)

        ctx->dsp.clear_block(blocks+(i<<6));

    init_get_bits(&gb, buf, buf_size << 3);

    decode_dc_coeffs(&gb, blocks, blocks_per_slice);

    if ((ret = decode_ac_coeffs(avctx, &gb, blocks, blocks_per_slice)) < 0)

        return ret;

    block = blocks;

    for (i = 0; i < slice->mb_count; i++) {

        for (j = 0; j < log2_blocks_per_mb; j++) {

            ctx->prodsp.idct_put(dst,              dst_stride, block+(0<<6), qmat);

            ctx->prodsp.idct_put(dst+4*dst_stride, dst_stride, block+(1<<6), qmat);

            block += 2*64;

            dst += 8;

        }

    }

    return 0;

}

static void unpack_alpha(GetBitContext *gb, uint16_t *dst, int num_coeffs,

                         const int num_bits)

{

    const int mask = (1 << num_bits) - 1;

    int i, idx, val, alpha_val;

    idx       = 0;

    alpha_val = mask;

    do {

        do {

            if (get_bits1(gb)) {

                val = get_bits(gb, num_bits);

            } else {

                int sign;

                val  = get_bits(gb, num_bits == 16 ? 7 : 4);

                sign = val & 1;

                val  = (val + 2) >> 1;

                if (sign)

                    val = -val;

            }

            alpha_val = (alpha_val + val) & mask;

            if (num_bits == 16) {

                dst[idx++] = alpha_val >> 6;

            } else {

                dst[idx++] = (alpha_val << 2) | (alpha_val >> 6);

            }

            if (idx >= num_coeffs)

                break;

        } while (get_bits_left(gb)>0 && get_bits1(gb));

        val = get_bits(gb, 4);

        if (!val)

            val = get_bits(gb, 11);

        if (idx + val > num_coeffs)

            val = num_coeffs - idx;

        if (num_bits == 16) {

            for (i = 0; i < val; i++)

                dst[idx++] = alpha_val >> 6;

        } else {

            for (i = 0; i < val; i++)

                dst[idx++] = (alpha_val << 2) | (alpha_val >> 6);

        }

    } while (idx < num_coeffs);

}

/**

 * Decode alpha slice plane.

 */

static void decode_slice_alpha(ProresContext *ctx,

                               uint16_t *dst, int dst_stride,

                               const uint8_t *buf, int buf_size,

                               int blocks_per_slice)

{

    GetBitContext gb;

    int i;

    LOCAL_ALIGNED_16(int16_t, blocks, [8*4*64]);

    int16_t *block;

    for (i = 0; i < blocks_per_slice<<2; i++)

        ctx->dsp.clear_block(blocks+(i<<6));

    init_get_bits(&gb, buf, buf_size << 3);

    if (ctx->alpha_info == 2) {

        unpack_alpha(&gb, blocks, blocks_per_slice * 4 * 64, 16);

    } else {

        unpack_alpha(&gb, blocks, blocks_per_slice * 4 * 64, 8);

    }

    block = blocks;

    for (i = 0; i < 16; i++) {

        memcpy(dst, block, 16 * blocks_per_slice * sizeof(*dst));

        dst   += dst_stride >> 1;

        block += 16 * blocks_per_slice;

    }

}

static int decode_slice_thread(AVCodecContext *avctx, void *arg, int jobnr, int threadnr)

{

    ProresContext *ctx = avctx->priv_data;

    SliceContext *slice = &ctx->slices[jobnr];

    const uint8_t *buf = slice->data;

    AVFrame *pic = ctx->frame;

    int i, hdr_size, qscale, log2_chroma_blocks_per_mb;

    int luma_stride, chroma_stride;

    int y_data_size, u_data_size, v_data_size, a_data_size;

    uint8_t *dest_y, *dest_u, *dest_v, *dest_a;

    int16_t qmat_luma_scaled[64];

    int16_t qmat_chroma_scaled[64];

    int mb_x_shift;

    int ret;

    slice->ret = -1;

    //av_log(avctx, AV_LOG_INFO, "slice %d mb width %d mb x %d y %d\n",

    //       jobnr, slice->mb_count, slice->mb_x, slice->mb_y);

    // slice header

    hdr_size = buf[0] >> 3;

    qscale = av_clip(buf[1], 1, 224);

    qscale = qscale > 128 ? qscale - 96 << 2: qscale;

    y_data_size = AV_RB16(buf + 2);

    u_data_size = AV_RB16(buf + 4);

    v_data_size = slice->data_size - y_data_size - u_data_size - hdr_size;

    if (hdr_size > 7) v_data_size = AV_RB16(buf + 6);

    a_data_size = slice->data_size - y_data_size - u_data_size -

                  v_data_size - hdr_size;

    if (y_data_size < 0 || u_data_size < 0 || v_data_size < 0

        || hdr_size+y_data_size+u_data_size+v_data_size > slice->data_size){

        av_log(avctx, AV_LOG_ERROR, "invalid plane data size\n");

        return AVERROR_INVALIDDATA;

    }

    buf += hdr_size;

    for (i = 0; i < 64; i++) {

        qmat_luma_scaled  [i] = ctx->qmat_luma  [i] * qscale;

        qmat_chroma_scaled[i] = ctx->qmat_chroma[i] * qscale;

    }

    if (ctx->frame_type == 0) {

        luma_stride   = pic->linesize[0];

        chroma_stride = pic->linesize[1];

    } else {

        luma_stride   = pic->linesize[0] << 1;

        chroma_stride = pic->linesize[1] << 1;

    }

    if (avctx->pix_fmt == AV_PIX_FMT_YUV444P10 || avctx->pix_fmt == AV_PIX_FMT_YUVA444P10) {

        mb_x_shift = 5;

        log2_chroma_blocks_per_mb = 2;

    } else {

        mb_x_shift = 4;

        log2_chroma_blocks_per_mb = 1;

    }

    dest_y = pic->data[0] + (slice->mb_y << 4) * luma_stride + (slice->mb_x << 5);

    dest_u = pic->data[1] + (slice->mb_y << 4) * chroma_stride + (slice->mb_x << mb_x_shift);

    dest_v = pic->data[2] + (slice->mb_y << 4) * chroma_stride + (slice->mb_x << mb_x_shift);

    dest_a = pic->data[3] + (slice->mb_y << 4) * luma_stride + (slice->mb_x << 5);

    if (ctx->frame_type && ctx->first_field ^ ctx->frame->top_field_first) {

        dest_y += pic->linesize[0];

        dest_u += pic->linesize[1];

        dest_v += pic->linesize[2];

        dest_a += pic->linesize[3];

    }

    ret = decode_slice_luma(avctx, slice, (uint16_t*)dest_y, luma_stride,

                            buf, y_data_size, qmat_luma_scaled);

    if (ret < 0)

        return ret;

    if (!(avctx->flags & CODEC_FLAG_GRAY)) {

        ret = decode_slice_chroma(avctx, slice, (uint16_t*)dest_u, chroma_stride,

                                  buf + y_data_size, u_data_size,

                                  qmat_chroma_scaled, log2_chroma_blocks_per_mb);

        if (ret < 0)

            return ret;

        ret = decode_slice_chroma(avctx, slice, (uint16_t*)dest_v, chroma_stride,

                                  buf + y_data_size + u_data_size, v_data_size,

                                  qmat_chroma_scaled, log2_chroma_blocks_per_mb);

        if (ret < 0)

            return ret;

    }

    /* decode alpha plane if available */

    if (ctx->alpha_info && pic->data[3] && a_data_size)

        decode_slice_alpha(ctx, (uint16_t*)dest_a, luma_stride,

                           buf + y_data_size + u_data_size + v_data_size,

                           a_data_size, slice->mb_count);

    slice->ret = 0;

    return 0;

}

static int decode_picture(AVCodecContext *avctx)

{

    ProresContext *ctx = avctx->priv_data;

    int i;

    avctx->execute2(avctx, decode_slice_thread, NULL, NULL, ctx->slice_count);

    for (i = 0; i < ctx->slice_count; i++)

        if (ctx->slices[i].ret < 0)

            return ctx->slices[i].ret;

    return 0;

}

static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,

                        AVPacket *avpkt)

{

    ProresContext *ctx = avctx->priv_data;

    AVFrame *frame = data;

    const uint8_t *buf = avpkt->data;

    int buf_size = avpkt->size;

    int frame_hdr_size, pic_size, ret;

    if (buf_size < 28 || AV_RL32(buf + 4) != AV_RL32("icpf")) {

        av_log(avctx, AV_LOG_ERROR, "invalid frame header\n");

        return AVERROR_INVALIDDATA;

    }

    ctx->frame = frame;

    ctx->frame->pict_type = AV_PICTURE_TYPE_I;

    ctx->frame->key_frame = 1;

    ctx->first_field = 1;

    buf += 8;

    buf_size -= 8;

    frame_hdr_size = decode_frame_header(ctx, buf, buf_size, avctx);

    if (frame_hdr_size < 0)

        return frame_hdr_size;

    buf += frame_hdr_size;

    buf_size -= frame_hdr_size;

    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)

        return ret;

 decode_picture:

    pic_size = decode_picture_header(avctx, buf, buf_size);

    if (pic_size < 0) {

        av_log(avctx, AV_LOG_ERROR, "error decoding picture header\n");

        return pic_size;

    }

    if ((ret = decode_picture(avctx)) < 0) {

        av_log(avctx, AV_LOG_ERROR, "error decoding picture\n");

        return ret;

    }

    buf += pic_size;

    buf_size -= pic_size;

    if (ctx->frame_type && buf_size > 0 && ctx->first_field) {

        ctx->first_field = 0;

        goto decode_picture;

    }

    *got_frame      = 1;

    return avpkt->size;

}

static av_cold int decode_close(AVCodecContext *avctx)

{

    ProresContext *ctx = avctx->priv_data;

    av_freep(&ctx->slices);

    return 0;

}

AVCodec ff_prores_decoder = {

    .name           = "prores",

    .long_name      = NULL_IF_CONFIG_SMALL("ProRes"),

    .type           = AVMEDIA_TYPE_VIDEO,

    .id             = AV_CODEC_ID_PRORES,

    .priv_data_size = sizeof(ProresContext),

    .init           = decode_init,

    .close          = decode_close,

    .decode         = decode_frame,

    .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_SLICE_THREADS,

};