FFmpeg/libavcodec/bsf/apv_metadata.c

/*
 * 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/common.h"
#include "libavutil/opt.h"

#include "libavcodec/bsf.h"
#include "libavcodec/bsf_internal.h"
#include "libavcodec/cbs.h"
#include "libavcodec/cbs_bsf.h"
#include "libavcodec/cbs_apv.h"

typedef struct APVMetadataContext {
    CBSBSFContext common;

    int color_primaries;
    int transfer_characteristics;
    int matrix_coefficients;
    int full_range_flag;

    int delete_filler;
} APVMetadataContext;


static int apv_metadata_update_frame_header(AVBSFContext *bsf,
                                            APVRawFrameHeader *hdr)
{
    APVMetadataContext *ctx = bsf->priv_data;

    if (ctx->color_primaries >= 0          ||
        ctx->transfer_characteristics >= 0 ||
        ctx->matrix_coefficients >= 0      ||
        ctx->full_range_flag >= 0) {
        hdr->color_description_present_flag = 1;

        if (ctx->color_primaries >= 0)
            hdr->color_primaries = ctx->color_primaries;
        if (ctx->transfer_characteristics >= 0)
            hdr->transfer_characteristics = ctx->transfer_characteristics;
        if (ctx->matrix_coefficients >= 0)
            hdr->matrix_coefficients = ctx->matrix_coefficients;
        if (ctx->full_range_flag >= 0)
            hdr->full_range_flag = ctx->full_range_flag;
    }

    return 0;
}

static int apv_metadata_update_fragment(AVBSFContext *bsf, AVPacket *pkt,
                                        CodedBitstreamFragment *frag)
{
    APVMetadataContext *ctx = bsf->priv_data;
    const CodedBitstreamAPVContext *priv = ctx->common.input->priv_data;
    int err, i;

    for (i = 0; i < frag->nb_units; i++) {
        if (frag->units[i].type == APV_PBU_PRIMARY_FRAME) {
            APVRawFrame *pbu = frag->units[i].content;
            err = apv_metadata_update_frame_header(bsf, &pbu->frame_header);
            if (err < 0)
                return err;
        }
    }

    if (ctx->delete_filler) {
        // Types of filler to delete:
        // - Filler PBUs.
        // - Filler at end of frame PBUs.
        // - Dummy bytes trailing in tile data.
        // - Filler at end of AU info PBUs.
        // - Filler at end of metadata PBUs.
        // - Filler metadata payloads.

        for (i = frag->nb_units - 1; i >= 0; i--) {
            switch (frag->units[i].type) {
            case APV_PBU_FILLER:
                ff_cbs_delete_unit(frag, i);
                break;
            case APV_PBU_PRIMARY_FRAME:
            case APV_PBU_NON_PRIMARY_FRAME:
            case APV_PBU_PREVIEW_FRAME:
            case APV_PBU_DEPTH_FRAME:
            case APV_PBU_ALPHA_FRAME:
                {
                    APVRawFrame *frame = frag->units[i].content;
                    frame->filler.filler_size = 0;
                    for (int t = 0; t < priv->num_tiles; t++)
                        frame->tile[t].tile_dummy_byte_size = 0;
                    // tile_size[t] may be wrong here, but are
                    // recalculated during CBS write.
                }
                break;
            case APV_PBU_ACCESS_UNIT_INFORMATION:
                {
                    APVRawAUInfo *au_info = frag->units[i].content;
                    au_info->filler.filler_size = 0;
                }
                break;
            case APV_PBU_METADATA:
                {
                    APVRawMetadata *md = frag->units[i].content;
                    int k = 0;
                    md->filler.filler_size = 0;
                    for (int j = 0; j < md->metadata_count; j++) {
                        APVRawMetadataPayload *pl = &md->payloads[j];
                        if (pl->payload_type == APV_METADATA_FILLER) {
                            // Drop this payload.
                        } else {
                            if (k < j)
                                md->payloads[k] = md->payloads[j];
                            ++k;
                        }
                    }
                    if (k == 0) {
                        // This metadata PBU contained only a filler
                        // payload, so now we have to delete the whole
                        // thing because a metadata PBU must contain at
                        // least one payload.
                        ff_cbs_delete_unit(frag, i);
                    } else {
                        md->metadata_count = k;
                        // metadata_size may be wrong here, but is
                        // recalculated during CBS write.
                    }
                }
                break;
            }
        }
    }

    return 0;
}

static const CBSBSFType apv_metadata_type = {
    .codec_id        = AV_CODEC_ID_APV,
    .fragment_name   = "access unit",
    .unit_name       = "PBU",
    .update_fragment = &apv_metadata_update_fragment,
};

static int apv_metadata_init(AVBSFContext *bsf)
{
    return ff_cbs_bsf_generic_init(bsf, &apv_metadata_type);
}

#define OFFSET(x) offsetof(APVMetadataContext, x)
#define FLAGS (AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_BSF_PARAM)
static const AVOption apv_metadata_options[] = {
    { "color_primaries", "Set color primaries (section 5.3.5)",
        OFFSET(color_primaries), AV_OPT_TYPE_INT,
        { .i64 = -1 }, -1, 255, FLAGS },
    { "transfer_characteristics", "Set transfer characteristics (section 5.3.5)",
        OFFSET(transfer_characteristics), AV_OPT_TYPE_INT,
        { .i64 = -1 }, -1, 255, FLAGS },
    { "matrix_coefficients", "Set matrix coefficients (section 5.3.5)",
        OFFSET(matrix_coefficients), AV_OPT_TYPE_INT,
        { .i64 = -1 }, -1, 255, FLAGS },

    { "full_range_flag", "Set full range flag flag (section 5.3.5)",
        OFFSET(full_range_flag), AV_OPT_TYPE_INT,
        { .i64 = -1 }, -1, 1, FLAGS, .unit = "cr" },
    { "tv", "TV (limited) range", 0, AV_OPT_TYPE_CONST,
        { .i64 = 0 }, .flags = FLAGS, .unit = "cr" },
    { "pc", "PC (full) range",    0, AV_OPT_TYPE_CONST,
        { .i64 = 1 }, .flags = FLAGS, .unit = "cr" },

    { "delete_filler", "Delete all filler in the stream",
        OFFSET(delete_filler), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, FLAGS },

    { NULL }
};

static const AVClass apv_metadata_class = {
    .class_name = "apv_metadata_bsf",
    .item_name  = av_default_item_name,
    .option     = apv_metadata_options,
    .version    = LIBAVUTIL_VERSION_INT,
};

static const enum AVCodecID apv_metadata_codec_ids[] = {
    AV_CODEC_ID_APV, AV_CODEC_ID_NONE,
};

const FFBitStreamFilter ff_apv_metadata_bsf = {
    .p.name         = "apv_metadata",
    .p.codec_ids    = apv_metadata_codec_ids,
    .p.priv_class   = &apv_metadata_class,
    .priv_data_size = sizeof(APVMetadataContext),
    .init           = &apv_metadata_init,
    .close          = &ff_cbs_bsf_generic_close,
    .filter         = &ff_cbs_bsf_generic_filter,
};