Function parse_profile_level

libavformat/whip.c:513–557

* When duplicating a stream, the demuxer has already set the extradata, profile, and * level of the par. Keep in mind that this function will not be invoked since the * profile and level are set. * * When utilizing an encoder, such as libx264, to encode a stream, the extradata in * par->extradata contains the SPS, which includes profile and level information. * However, the profile and level

 * the extradata will remain empty.
 */
static int parse_profile_level(AVFormatContext *s, AVCodecParameters *par)
{
    int ret = 0;
    const uint8_t *r = par->extradata, *r1, *end = par->extradata + par->extradata_size;
    H264SPS seq, *const sps = &seq;
    uint32_t state;
    WHIPContext *whip = s->priv_data;

    if (par->codec_id != AV_CODEC_ID_H264)
        return ret;

    if (par->profile != AV_PROFILE_UNKNOWN && par->level != AV_LEVEL_UNKNOWN)
        return ret;

    if (!par->extradata || par->extradata_size <= 0) {
        av_log(whip, AV_LOG_ERROR, "Unable to parse profile from empty extradata=%p, size=%d\n",
            par->extradata, par->extradata_size);
        return AVERROR(EINVAL);
    }

    while (1) {
        r = avpriv_find_start_code(r, end, &state);
        if (r >= end)
            break;

        r1 = ff_nal_find_startcode(r, end);
        if ((state & 0x1f) == H264_NAL_SPS) {
            ret = ff_avc_decode_sps(sps, r, r1 - r);
            if (ret < 0) {
                av_log(whip, AV_LOG_ERROR, "Failed to decode SPS, state=%x, size=%d\n",
                    state, (int)(r1 - r));
                return ret;
            }

            av_log(whip, AV_LOG_VERBOSE, "Parse profile=%d, level=%d from SPS\n",
                sps->profile_idc, sps->level_idc);
            par->profile = sps->profile_idc;
            par->level = sps->level_idc;
        }

        r = r1;
    }

    return ret;
}

/**
 * Parses video SPS/PPS from the extradata of codecpar and checks the codec.