} else { return -1;
static int sdp_parse_rtpmap(AVCodecContext *codec, const char *p){    char buf[256];    /* codec name */    get_word_sep(buf, sizeof(buf), "/", &p);    if (!strcmp(buf, "MP4V-ES")) {        codec->codec_id = CODEC_ID_MPEG4;        return 0;    } else {        return -1;    }}