lcevcdec.c

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/*
 * 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 "libavutil/avassert.h"
#include "libavutil/frame.h"
#include "libavutil/imgutils.h"
#include "libavutil/log.h"
#include "libavutil/mem.h"
#include "libavutil/opt.h"
#include "libavutil/refstruct.h"
 
#include "cbs.h"
#include "cbs_lcevc.h"
#include "decode.h"
#include "lcevc_parse.h"
#include "lcevcdec.h"
#include "lcevctab.h"
 
static LCEVC_ColorFormat map_format(int format)
{
    switch (format) {
    case AV_PIX_FMT_YUV420P:
        return LCEVC_I420_8;
    case AV_PIX_FMT_YUV420P10:
        return LCEVC_I420_10_LE;
    case AV_PIX_FMT_YUV420P12:
        return LCEVC_I420_12_LE;
    case AV_PIX_FMT_YUV420P14:
        return LCEVC_I420_14_LE;
    case AV_PIX_FMT_YUV422P:
        return LCEVC_I422_8;
    case AV_PIX_FMT_YUV422P10:
        return LCEVC_I422_10_LE;
    case AV_PIX_FMT_YUV422P12:
        return LCEVC_I422_12_LE;
    case AV_PIX_FMT_YUV422P14:
        return LCEVC_I422_14_LE;
    case AV_PIX_FMT_YUV444P:
        return LCEVC_I444_8;
    case AV_PIX_FMT_YUV444P10:
        return LCEVC_I444_10_LE;
    case AV_PIX_FMT_YUV444P12:
        return LCEVC_I444_12_LE;
    case AV_PIX_FMT_YUV444P14:
        return LCEVC_I444_14_LE;
    case AV_PIX_FMT_NV12:
        return LCEVC_NV12_8;
    case AV_PIX_FMT_NV21:
        return LCEVC_NV21_8;
    case AV_PIX_FMT_GRAY8:
        return LCEVC_GRAY_8;
    case AV_PIX_FMT_GRAY10LE:
        return LCEVC_GRAY_10_LE;
    case AV_PIX_FMT_GRAY12LE:
        return LCEVC_GRAY_12_LE;
    case AV_PIX_FMT_GRAY14LE:
        return LCEVC_GRAY_14_LE;
    }
 
    return LCEVC_ColorFormat_Unknown;
}
 
static int alloc_base_frame(FFLCEVCContext *lcevc, const AVFrame *frame,
                            LCEVC_PictureDesc *desc, LCEVC_PictureHandle *picture)
{
    LCEVC_ColorFormat fmt = map_format(frame->format);
    LCEVC_PicturePlaneDesc planes[AV_VIDEO_MAX_PLANES] = { 0 };
    int width = frame->width - frame->crop_left - frame->crop_right;
    int height = frame->height - frame->crop_top - frame->crop_bottom;
    LCEVC_ReturnCode res;
 
    res = LCEVC_DefaultPictureDesc(desc, fmt, width, height);
    if (res != LCEVC_Success)
        return AVERROR_EXTERNAL;
 
    desc->cropTop    = frame->crop_top;
    desc->cropBottom = frame->crop_bottom;
    desc->cropLeft   = frame->crop_left;
    desc->cropRight  = frame->crop_right;
    desc->sampleAspectRatioNum  = frame->sample_aspect_ratio.num;
    desc->sampleAspectRatioDen  = frame->sample_aspect_ratio.den;
    desc->colorRange = LCEVC_ColorRange_Unknown;
    if (frame->color_range == AVCOL_RANGE_JPEG)
        desc->colorRange = LCEVC_ColorRange_Full;
    else if (frame->color_range == AVCOL_RANGE_MPEG)
        desc->colorRange = LCEVC_ColorRange_Limited;
    desc->colorPrimaries = (LCEVC_ColorPrimaries)frame->color_primaries;
    desc->matrixCoefficients = (LCEVC_MatrixCoefficients)frame->colorspace;
    desc->transferCharacteristics = (LCEVC_TransferCharacteristics)frame->color_trc;
 
    for (int i = 0; i < AV_VIDEO_MAX_PLANES; i++) {
        planes[i].firstSample = frame->data[i];
        planes[i].rowByteStride = frame->linesize[i];
    }
 
    /* Allocate LCEVC Picture */
    res = LCEVC_AllocPictureExternal(lcevc->decoder, desc, NULL, planes, picture);
    if (res != LCEVC_Success) {
        return AVERROR_EXTERNAL;
    }
 
    return 0;
}
 
static int alloc_enhanced_frame(FFLCEVCFrame *frame_ctx,
                                LCEVC_PictureHandle *picture)
{
    FFLCEVCContext *lcevc = frame_ctx->lcevc;
    LCEVC_PictureDesc desc ;
    LCEVC_ColorFormat fmt = map_format(frame_ctx->frame->format);
    LCEVC_PicturePlaneDesc planes[4] = { 0 };
    LCEVC_ReturnCode res;
 
    res = LCEVC_DefaultPictureDesc(&desc, fmt, frame_ctx->frame->width, frame_ctx->frame->height);
    if (res != LCEVC_Success)
        return AVERROR_EXTERNAL;
 
    /* Set plane description */
    for (int i = 0; i < 4; i++) {
        planes[i].firstSample = frame_ctx->frame->data[i];
        planes[i].rowByteStride = frame_ctx->frame->linesize[i];
    }
 
    /* Allocate LCEVC Picture */
    res = LCEVC_AllocPictureExternal(lcevc->decoder, &desc, NULL, planes, picture);
    if (res != LCEVC_Success) {
        return AVERROR_EXTERNAL;
    }
    return 0;
}
 
static int lcevc_flush_pictures(FFLCEVCContext *lcevc)
{
    LCEVC_PictureHandle picture;
    LCEVC_ReturnCode res;
 
    while (1) {
        AVFrame *base = NULL;
        res = LCEVC_ReceiveDecoderBase (lcevc->decoder, &picture);
        if (res != LCEVC_Success && res != LCEVC_Again)
            return AVERROR_EXTERNAL;
 
        if (res == LCEVC_Again)
            break;
 
        LCEVC_GetPictureUserData(lcevc->decoder, picture, (void **)&base);
        av_frame_free(&base);
 
        res = LCEVC_FreePicture(lcevc->decoder, picture);
        if (res != LCEVC_Success)
            return AVERROR_EXTERNAL;
    }
 
    return 0;
}
 
static int lcevc_send_frame(FFLCEVCFrame *frame_ctx, const AVFrame *in)
{
    FFLCEVCContext *lcevc = frame_ctx->lcevc;
    LCEVC_ColorFormat fmt = map_format(in->format);
    const AVFrameSideData *sd = av_frame_get_side_data(in, AV_FRAME_DATA_LCEVC);
    AVFrame *opaque;
    LCEVC_PictureHandle picture;
    LCEVC_PictureDesc desc, base_desc;
    LCEVC_ReturnCode res;
    int ret;
 
    if (!sd || fmt == LCEVC_ColorFormat_Unknown || lcevc->passthrough_mode == 1)
        return 1;
 
    res = LCEVC_SendDecoderEnhancementData(lcevc->decoder, lcevc->last_pts,
                                           sd->data, sd->size);
    if (res != LCEVC_Success) {
        ret = AVERROR_EXTERNAL;
        goto end;
    }
 
    ret = alloc_base_frame(lcevc, in, &base_desc, &picture);
    if (ret < 0)
        goto fail;
 
    opaque = av_frame_clone(in);
    if (!opaque) {
        LCEVC_FreePicture(lcevc->decoder, picture);
        ret = AVERROR(ENOMEM);
        goto fail;
    }
 
    res = LCEVC_SetPictureUserData(lcevc->decoder, picture, opaque);
    if (res != LCEVC_Success) {
        LCEVC_FreePicture(lcevc->decoder, picture);
        av_frame_free(&opaque);
        ret = AVERROR_EXTERNAL;
        goto fail;
    }
 
    res = LCEVC_SendDecoderBase(lcevc->decoder, lcevc->last_pts, picture, -1, opaque);
    if (res != LCEVC_Success) {
        LCEVC_FreePicture(lcevc->decoder, picture);
        av_frame_free(&opaque);
        ret = AVERROR_EXTERNAL;
        goto fail;
    }
 
    res = LCEVC_PeekDecoderPictureDesc(lcevc->decoder, lcevc->last_pts, &desc);
    if (res != LCEVC_Success ||
        desc.width       != frame_ctx->frame->width  ||
        desc.height      != frame_ctx->frame->height ||
        desc.colorFormat != map_format(frame_ctx->frame->format)) {
        if (res == LCEVC_Success &&
            desc.width       == base_desc.width  &&
            desc.height      == base_desc.height &&
            desc.colorFormat == base_desc.colorFormat) {
            av_log(lcevc, AV_LOG_VERBOSE, "Passing the base picture through\n");
            ret = 1;
            goto fail;
        }
        av_log(lcevc, AV_LOG_ERROR, "Output picture does not match the enhancement data\n");
        ret = AVERROR_INVALIDDATA;
        goto fail;
    }
 
    memset(&picture, 0, sizeof(picture));
    ret = alloc_enhanced_frame(frame_ctx, &picture);
    if (ret < 0)
        goto fail;
 
    res = LCEVC_SendDecoderPicture(lcevc->decoder, picture);
    if (res != LCEVC_Success) {
        LCEVC_FreePicture(lcevc->decoder, picture);
        ret = AVERROR_EXTERNAL;
        goto fail;
    }
 
    ret = 0;
    goto end;
fail:
    LCEVC_SkipDecoder(lcevc->decoder, lcevc->last_pts);
    LCEVC_SynchronizeDecoder(lcevc->decoder, 0);
    lcevc_flush_pictures(lcevc);
end:
    lcevc->last_pts++;
 
    return ret;
}
 
static int generate_output(FFLCEVCFrame *frame_ctx, AVFrame *out)
{
    FFLCEVCContext *lcevc = frame_ctx->lcevc;
    LCEVC_PictureDesc desc;
    LCEVC_DecodeInformation info;
    LCEVC_PictureHandle picture;
    LCEVC_ReturnCode res;
 
    do {
        res = LCEVC_ReceiveDecoderPicture(lcevc->decoder, &picture, &info);
    } while (res == LCEVC_Again);
    if (res != LCEVC_Success)
        return AVERROR_EXTERNAL;
 
    res = LCEVC_GetPictureDesc(lcevc->decoder, picture, &desc);
    if (res != LCEVC_Success) {
        LCEVC_FreePicture(lcevc->decoder, picture);
        return AVERROR_EXTERNAL;
    }
 
    av_frame_unref(out);
    av_frame_copy_props(frame_ctx->frame, (AVFrame *)info.baseUserData);
    av_frame_move_ref(out, frame_ctx->frame);
 
    out->crop_top = desc.cropTop;
    out->crop_bottom = desc.cropBottom;
    out->crop_left = desc.cropLeft;
    out->crop_right = desc.cropRight;
    out->sample_aspect_ratio.num = desc.sampleAspectRatioNum;
    out->sample_aspect_ratio.den = desc.sampleAspectRatioDen;
    out->width = desc.width + out->crop_left + out->crop_right;
    out->height = desc.height + out->crop_top + out->crop_bottom;
    out->color_range = AVCOL_RANGE_UNSPECIFIED;
    if (desc.colorRange == LCEVC_ColorRange_Full)
        out->color_range = AVCOL_RANGE_JPEG;
    else if (desc.colorRange == LCEVC_ColorRange_Limited)
        out->color_range = AVCOL_RANGE_MPEG;
    out->color_primaries = (enum AVColorPrimaries)desc.colorPrimaries;
    out->colorspace = (enum AVColorSpace)desc.matrixCoefficients;
    out->color_trc = (enum AVColorTransferCharacteristic)desc.transferCharacteristics;
 
    av_log(lcevc, AV_LOG_DEBUG,  "out PTS %"PRId64", %dx%d, "
                                 "%zu/%zu/%zu/%zu, "
                                 "SAR %d:%d, "
                                 "color_range %d, color_primaries %d, colorspace %d, color_trc %d, "
                                 "hasEnhancement %d, enhanced %d\n",
           out->pts, out->width, out->height,
           out->crop_top, out->crop_bottom, out->crop_left, out->crop_right,
           out->sample_aspect_ratio.num, out->sample_aspect_ratio.den,
           out->color_range, out->color_primaries, out->colorspace, out->color_trc,
           info.hasEnhancement, info.enhanced);
 
    res = LCEVC_FreePicture(lcevc->decoder, picture);
    if (res != LCEVC_Success)
        return AVERROR_EXTERNAL;
 
    return 0;
}
 
static int lcevc_receive_frame(FFLCEVCFrame *frame_ctx, AVFrame *out)
{
    FFLCEVCContext *lcevc = frame_ctx->lcevc;
    int ret;
 
    ret = generate_output(frame_ctx, out);
    if (ret < 0)
        return ret;
 
    return lcevc_flush_pictures(lcevc);
}
 
static const uint8_t level_map[LCEVC_LogLevelCount] = {
    [LCEVC_LogFatal]   = AV_LOG_FATAL,
    [LCEVC_LogError]   = AV_LOG_ERROR,
    [LCEVC_LogWarning] = AV_LOG_WARNING,
    [LCEVC_LogInfo]    = AV_LOG_INFO,
    [LCEVC_LogDebug]   = AV_LOG_DEBUG,
    [LCEVC_LogTrace]   = AV_LOG_TRACE,
};
 
static void event_callback(LCEVC_DecoderHandle dec, LCEVC_Event event,
    LCEVC_PictureHandle pic, const LCEVC_DecodeInformation *info,
    const uint8_t *data, uint32_t size, void *logctx)
{
    switch (event) {
    case LCEVC_Log: {
        unsigned int level = 0;
        if (size < 3)
            break;
        int ret = sscanf(data, "%u ", &level);
        if (ret != 1 || level >= LCEVC_LogLevelCount || !level_map[level])
            break;
        av_log(logctx, level_map[level], "%s\n", data + 2);
        break;
    }
    default:
        break;
    }
}
 
static void lcevc_free(AVRefStructOpaque unused, void *obj)
{
    FFLCEVCContext *lcevc = obj;
    if (lcevc->initialized == FF_LCEVCDEC_INIT) {
        LCEVC_FlushDecoder(lcevc->decoder);
        lcevc_flush_pictures(lcevc);
        LCEVC_DestroyDecoder(lcevc->decoder);
    }
    if (lcevc->frag)
        ff_cbs_fragment_free(lcevc->frag);
    av_freep(&lcevc->frag);
    ff_cbs_close(&lcevc->cbc);
    av_refstruct_pool_uninit(&lcevc->frame_pool);
    av_opt_free(lcevc);
    memset(lcevc, 0, sizeof(*lcevc));
}
 
static av_cold int lcevc_frame_init_cb(AVRefStructOpaque unused, void *obj)
{
    FFLCEVCFrame *frame = obj;
 
    frame->frame = av_frame_alloc();
    if (!frame->frame)
        return AVERROR(ENOMEM);
    return 0;
}
 
static void lcevc_frame_reset_cb(AVRefStructOpaque unused, void *obj)
{
    FFLCEVCFrame *frame = obj;
 
    av_frame_unref(frame->frame);
    av_refstruct_unref(&frame->lcevc);
}
 
static av_cold void lcevc_frame_free_entry_cb(AVRefStructOpaque unused, void *obj)
{
    FFLCEVCFrame *frame = obj;
 
    av_frame_free(&frame->frame);
}
 
static int get_log_level(int level)
{
    if (level <= AV_LOG_QUIET)
        return LCEVC_LogDisabled;
    if (level <= AV_LOG_FATAL)
        return LCEVC_LogFatal;
    if (level <= AV_LOG_ERROR)
        return LCEVC_LogError;
    if (level <= AV_LOG_WARNING)
        return LCEVC_LogWarning;
    if (level <= AV_LOG_INFO)
        return LCEVC_LogInfo;
    if (level <= AV_LOG_DEBUG)
        return LCEVC_LogDebug;
 
    return LCEVC_LogTrace;
}
 
static int lcevc_init(FFLCEVCContext *lcevc)
{
    LCEVC_AccelContextHandle dummy = { 0 };
    const int32_t event = LCEVC_Log;
    LCEVC_ReturnCode res;
    int level;
 
    lcevc->initialized = FF_LCEVCDEC_FAIL;
 
    if (LCEVC_CreateDecoder(&lcevc->decoder, dummy) != LCEVC_Success) {
        av_log(lcevc, AV_LOG_ERROR, "Failed to create LCEVC decoder\n");
        return AVERROR_EXTERNAL;
    }
 
    if (lcevc->pipeline) {
        res = LCEVC_ConfigureDecoderString(lcevc->decoder, "pipeline", lcevc->pipeline);
        if (res != LCEVC_Success) {
            av_log(lcevc, AV_LOG_ERROR, "Failed to set pipeline to \"%s\"\n", lcevc->pipeline);
            LCEVC_DestroyDecoder(lcevc->decoder);
            return AVERROR_EXTERNAL;
        }
    }
 
    level = get_log_level(lcevc->loglevel);
 
    LCEVC_ConfigureDecoderInt(lcevc->decoder, "log_level", level);
    res = LCEVC_ConfigureDecoderInt(lcevc->decoder, "threads", lcevc->threads);
    if (res != LCEVC_Success) {
        av_log(lcevc, AV_LOG_ERROR, "Failed to set threads to %d\n", lcevc->threads);
        LCEVC_DestroyDecoder(lcevc->decoder);
        return AVERROR_EXTERNAL;
    }
    res = LCEVC_ConfigureDecoderInt(lcevc->decoder, "passthrough_mode", lcevc->passthrough_mode);
    if (res != LCEVC_Success) {
        av_log(lcevc, AV_LOG_ERROR, "Failed to set passthrough_mode to %d\n", lcevc->passthrough_mode);
        LCEVC_DestroyDecoder(lcevc->decoder);
        return AVERROR_EXTERNAL;
    }
    res = LCEVC_ConfigureDecoderBool(lcevc->decoder, "allow_dithering", lcevc->allow_dithering);
    if (res != LCEVC_Success) {
        av_log(lcevc, AV_LOG_ERROR, "Failed to set allow_dithering to %d\n", lcevc->allow_dithering);
        LCEVC_DestroyDecoder(lcevc->decoder);
        return AVERROR_EXTERNAL;
    }
    res = LCEVC_ConfigureDecoderBool(lcevc->decoder, "highlight_residuals", lcevc->highlight_residuals);
    if (res != LCEVC_Success) {
        av_log(lcevc, AV_LOG_ERROR, "Failed to set highlight_residuals to %d\n", lcevc->highlight_residuals);
        LCEVC_DestroyDecoder(lcevc->decoder);
        return AVERROR_EXTERNAL;
    }
    LCEVC_ConfigureDecoderIntArray(lcevc->decoder, "events", 1, &event);
    LCEVC_SetDecoderEventCallback(lcevc->decoder, event_callback, lcevc);
 
    if (LCEVC_InitializeDecoder(lcevc->decoder) != LCEVC_Success) {
        av_log(lcevc, AV_LOG_ERROR, "Failed to initialize LCEVC decoder\n");
        LCEVC_DestroyDecoder(lcevc->decoder);
        return AVERROR_EXTERNAL;
    }
 
    lcevc->initialized = FF_LCEVCDEC_INIT;
 
    return 0;
}
 
int ff_lcevc_process(void *logctx, AVFrame *frame)
{
    FrameDecodeData  *fdd = frame->private_ref;
    FFLCEVCFrame *frame_ctx = fdd->post_process_opaque;
    FFLCEVCContext *lcevc = frame_ctx->lcevc;
    int ret;
 
    if (lcevc->initialized == FF_LCEVCDEC_UNINIT) {
        ret = lcevc_init(lcevc);
        if (ret < 0)
            return ret;
    } else if (lcevc->initialized == FF_LCEVCDEC_FAIL)
        return 0;
 
    av_assert0(frame_ctx->frame);
 
 
    ret = lcevc_send_frame(frame_ctx, frame);
    if (ret)
        return ret < 0 ? ret : 0;
 
    ret = lcevc_receive_frame(frame_ctx, frame);
    if (ret < 0)
        return ret;
 
    av_frame_remove_side_data(frame, AV_FRAME_DATA_LCEVC);
 
    return 0;
}
 
int ff_lcevc_parse_frame(FFLCEVCContext *lcevc, const AVFrame *frame,
                         enum AVPixelFormat *format, enum AVPixelFormat *base_format,
                         int *width, int *height)
{
    LCEVCRawProcessBlock *block = NULL;
    const LCEVCRawGlobalConfig *gc;
    const AVFrameSideData *sd = av_frame_get_side_data(frame, AV_FRAME_DATA_LCEVC);
    int ret;
 
    ret = ff_cbs_read(lcevc->cbc, lcevc->frag, NULL, sd->data, sd->size);
    if (ret < 0) {
        av_log(lcevc, AV_LOG_ERROR, "Failed to parse Access Unit.\n");
        goto end;
    }
 
    ret = ff_cbs_lcevc_find_process_block(lcevc->cbc, lcevc->frag,
                                          LCEVC_PAYLOAD_TYPE_GLOBAL_CONFIG, &block);
    if (ret < 0) {
        ret = 0;
        goto end;
    }
 
    gc = block->payload;
 
    *format = ff_lcevc_depth_type[gc->enhancement_depth_type][gc->chroma_sampling_type];
    *base_format = ff_lcevc_depth_type[gc->base_depth_type][gc->chroma_sampling_type];
    if (gc->resolution_type < 63) {
        *width  = ff_lcevc_resolution_type[gc->resolution_type].width;
        *height = ff_lcevc_resolution_type[gc->resolution_type].height;
    } else {
        *width  = gc->custom_resolution_width;
        *height = gc->custom_resolution_height;
    }
 
    ret = 0;
end:
    ff_cbs_fragment_reset(lcevc->frag);
 
    return ret;
}
 
static const CodedBitstreamUnitType decompose_unit_types[] = {
    LCEVC_IDR_NUT,
    LCEVC_NON_IDR_NUT,
};
 
#define OFFSET(x) offsetof(FFLCEVCContext, x)
#define FLAGS (AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_DECODING_PARAM)
static const AVOption lcevc_opts[] = {
    { "passthrough_mode", "Set passthrough mode", OFFSET(passthrough_mode), AV_OPT_TYPE_INT,
            { .i64 = 0 }, -1, 2, FLAGS, .unit = "passthrough_mode" },
        { "disable", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = -1 }, .unit = "passthrough_mode" },
        { "allow",   NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 0 },  .unit = "passthrough_mode" },
        { "force",   NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 1 },  .unit = "passthrough_mode" },
        { "scale",   NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 2 },  .unit = "passthrough_mode" },
    { "allow_dithering", "Allow dithering", OFFSET(allow_dithering), AV_OPT_TYPE_BOOL,
            { .i64 = 1 }, 0, 1, FLAGS },
    { "highlight_residuals", "Highlight residuals", OFFSET(highlight_residuals), AV_OPT_TYPE_BOOL,
            { .i64 = 0 }, 0, 1, FLAGS },
    { "threads", "Thread count", OFFSET(threads), AV_OPT_TYPE_INT,
            { .i64 = 1 }, 0, INT_MAX, FLAGS },
    { "pipeline", "Decoding pipeline", OFFSET(pipeline), AV_OPT_TYPE_STRING,
            { .str = NULL }, 0, 0, FLAGS },
    { NULL },
};
#undef OFFSET
#undef FLAGS
 
static const AVClass lcevcdec_context_class = {
    .class_name     = "liblcevc_dec",
    .item_name      = av_default_item_name,
    .option         = lcevc_opts,
    .version        = LIBAVUTIL_VERSION_INT,
    .category       = AV_CLASS_CATEGORY_DECODER,
};
 
int ff_lcevc_alloc(FFLCEVCContext **plcevc, AVDictionary **options, int loglevel)
{
    FFLCEVCContext *lcevc = NULL;
    const AVDictionaryEntry *t;
    int ret;
 
    lcevc = av_refstruct_alloc_ext(sizeof(*lcevc), 0, NULL, lcevc_free);
    if (!lcevc)
        return AVERROR(ENOMEM);
 
    lcevc->class = &lcevcdec_context_class;
    av_opt_set_defaults(lcevc);
 
    lcevc->loglevel = loglevel;
 
    ret = av_opt_set_dict2(lcevc, options, 0);
    if (ret < 0)
        goto fail;
 
    if (t = av_dict_iterate(*options, NULL)) {
        av_log(NULL, AV_LOG_FATAL, "liblcevc-dec option %s not found.\n", t->key);
        ret = AVERROR_OPTION_NOT_FOUND;
        goto fail;
    }
 
    lcevc->frag = av_mallocz(sizeof(*lcevc->frag));
    if (!lcevc->frag) {
        ret = AVERROR(ENOMEM);
        goto fail;
    }
 
    ret = ff_cbs_init(&lcevc->cbc, AV_CODEC_ID_LCEVC, lcevc);
    if (ret < 0)
        goto fail;
 
    lcevc->cbc->decompose_unit_types    = decompose_unit_types;
    lcevc->cbc->nb_decompose_unit_types = FF_ARRAY_ELEMS(decompose_unit_types);
 
    lcevc->frame_pool = av_refstruct_pool_alloc_ext(sizeof(FFLCEVCFrame), 0, NULL,
                                                    lcevc_frame_init_cb,
                                                    lcevc_frame_reset_cb,
                                                    lcevc_frame_free_entry_cb, NULL);
    if (!lcevc->frame_pool) {
        ret = AVERROR(ENOMEM);
        goto fail;
    }
 
    *plcevc = lcevc;
    return 0;
fail:
    av_refstruct_unref(&lcevc);
    return ret;
}