Function ff_mjpeg_decode_frame_from_buf

libavcodec/mjpegdec.c:2397–2900

}

int ff_mjpeg_decode_frame_from_buf(AVCodecContext *avctx, AVFrame *frame,
                                   int *got_frame, const AVPacket *avpkt,
                                   const uint8_t *buf, const int buf_size)
{
    MJpegDecodeContext *s = avctx->priv_data;
    const uint8_t *buf_end, *buf_ptr;
    int hshift, vshift;
    int start_code;
    int index;
    int ret = 0;
    int is16bit;

    s->force_pal8 = 0;

    s->buf_size = buf_size;

    av_exif_free(&s->exif_metadata);
    av_freep(&s->stereo3d);
    s->adobe_transform = -1;

    if (s->iccnum != 0)
        reset_icc_profile(s);

redo_for_pal8:
    buf_ptr = buf;
    buf_end = buf + buf_size;
    while (buf_ptr < buf_end) {
        /* find start next marker */
        start_code = ff_mjpeg_find_marker(&buf_ptr, buf_end);
        /* EOF */
        if (start_code < 0)
            break;

        ptrdiff_t bytes_left = buf_end - buf_ptr;
        if (bytes_left > INT_MAX / 8) {
            av_log(avctx, AV_LOG_ERROR,
                   "MJPEG packet 0x%x too big (%td/%d), corrupt data?\n",
                   start_code, bytes_left, buf_size);
            return AVERROR_INVALIDDATA;
        }
        av_log(avctx, AV_LOG_DEBUG, "marker=%x avail_size_in_buf=%td\n",
               start_code, buf_end - buf_ptr);

        bytestream2_init(&s->gB, buf_ptr, bytes_left);

        if (avctx->debug & FF_DEBUG_STARTCODE)
            av_log(avctx, AV_LOG_DEBUG, "startcode: %X\n", start_code);

        /* process markers */
        if (start_code >= RST0 && start_code <= RST7) {
            av_log(avctx, AV_LOG_DEBUG,
                   "restart marker: %d\n", start_code & 0x0f);
            /* APP fields */
        } else if (start_code >= APP0 && start_code <= APP15) {
            if ((ret = mjpeg_decode_app(s, start_code)) < 0)
                av_log(avctx, AV_LOG_ERROR, "unable to decode APP fields: %s\n",
                       av_err2str(ret));
            /* Comment */