Function transcode_subtitles

fftools/ffmpeg_dec.c:641–697

}

static int transcode_subtitles(DecoderPriv *dp, const AVPacket *pkt,
                               AVFrame *frame)
{
    AVPacket *flush_pkt = NULL;
    AVSubtitle subtitle;
    int got_output;
    int ret;

    if (pkt && (intptr_t)pkt->opaque == PKT_OPAQUE_SUB_HEARTBEAT) {
        frame->pts       = pkt->pts;
        frame->time_base = pkt->time_base;
        frame->opaque    = (void*)(intptr_t)FRAME_OPAQUE_SUB_HEARTBEAT;

        ret = sch_dec_send(dp->sch, dp->sch_idx, 0, frame);
        return ret == AVERROR_EOF ? AVERROR_EXIT : ret;
    } else if (pkt && (intptr_t)pkt->opaque == PKT_OPAQUE_FIX_SUB_DURATION) {
        return fix_sub_duration_heartbeat(dp, av_rescale_q(pkt->pts, pkt->time_base,
                                                           AV_TIME_BASE_Q));
    }

    if (!pkt) {
        flush_pkt = av_packet_alloc();
        if (!flush_pkt)
            return AVERROR(ENOMEM);
    }

    ret = avcodec_decode_subtitle2(dp->dec_ctx, &subtitle, &got_output,
                                   pkt ? pkt : flush_pkt);
    av_packet_free(&flush_pkt);

    if (ret < 0) {
        av_log(dp, AV_LOG_ERROR, "Error decoding subtitles: %s\n",
               av_err2str(ret));
        dp->dec.decode_errors++;
        return exit_on_error ? ret : 0;
    }

    if (!got_output)
        return pkt ? 0 : AVERROR_EOF;

    dp->dec.frames_decoded++;

    // XXX the queue for transferring data to consumers runs
    // on AVFrames, so we wrap AVSubtitle in an AVBufferRef and put that
    // inside the frame
    // eventually, subtitles should be switched to use AVFrames natively
    ret = subtitle_wrap_frame(frame, &subtitle, 0);
    if (ret < 0) {
        avsubtitle_free(&subtitle);
        return ret;
    }

    frame->width  = dp->dec_ctx->width;
    frame->height = dp->dec_ctx->height;

    return process_subtitle(dp, frame);
}