PJSUA已经支持H264,H263,但是 如何添加 H261，MJPEG这些 编解码？

[yhrainOO]

static ffmpeg_codec_desc codec_desc[] =
{
#if PJMEDIA_HAS_FFMPEG_CODEC_H264
{
{PJMEDIA_FORMAT_H264, PJMEDIA_RTP_PT_H264, {"H264",4},
{"Constrained Baseline (level=30, pack=1)", 39}},
0,
{720, 480}, {15, 1}, 256000, 256000,
&h264_packetize, &h264_unpacketize, &h264_preopen, &h264_postopen,
&pjmedia_vid_codec_h264_match_sdp,
/* Leading space for better compatibility (strange indeed!) */
{2, { {{"profile-level-id",16}, {"42e01e",6}},
{{" packetization-mode",19}, {"1",1}}, } },
},
#endif

#if PJMEDIA_HAS_FFMPEG_CODEC_H263P
{
{PJMEDIA_FORMAT_H263P, PJMEDIA_RTP_PT_H263P, {"H263-1998",9}},
PJMEDIA_FORMAT_H263,
{352, 288}, {15, 1}, 256000, 256000,
&h263_packetize, &h263_unpacketize, &h263_preopen, NULL, NULL,
{2, { {{"CIF",3}, {"1",1}},
{{"QCIF",4}, {"1",1}}, } },
},
#endif

{
{PJMEDIA_FORMAT_H263, PJMEDIA_RTP_PT_H263, {"H263",4}},
},
{
{PJMEDIA_FORMAT_H261, PJMEDIA_RTP_PT_H261, {"H261",4}},
},
{
{PJMEDIA_FORMAT_MJPEG, PJMEDIA_RTP_PT_JPEG, {"JPEG",4}},
PJMEDIA_FORMAT_MJPEG, {640, 480}, {25, 1},
},
{
{PJMEDIA_FORMAT_MPEG4, 0, {"MP4V",4}},
PJMEDIA_FORMAT_MPEG4, {640, 480}, {25, 1},
},
};

根据这个 PJSUA已经支持H264，H263p。想添加 H261 ，MJPEG ,不知道 还需要添加哪些信息？
有谁做过这方面的？ 可否指导一二？