Pjsip/Pjsua video problem : frame buffer too small

Question

I try to make a sip video call using Pjsip/Pjsua on my raspberry pi 3. Before coding, I'm using the main sample app to test different options. Everything seems to work (registering, audio calling,..) but when I try to start a video call, the programs stops with the following message :

pjsua-armv7l-unknown-linux-gnueabihf: ../src/pjmedia-videodev/v4l2_dev.c:737: vid4lin_stream_get_frame_mmap: Assertion `!"frame buffer is too small for v4l2"' failed.

I've searched a lot, including the source code :

/* get frame from mmap */
static pj_status_t vid4lin_stream_get_frame_mmap(vid4lin_stream *stream, pjmedia_frame *frame)
{
struct v4l2_buffer buf;
pj_time_val time;
pj_status_t status = PJ_SUCCESS;

pj_bzero(&buf, sizeof(buf));
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
status = xioctl(stream->fd, VIDIOC_DQBUF, &buf);
if (status != PJ_SUCCESS)
return status;

if (frame->size < buf.bytesused) {
/* supplied buffer is too small */
pj_assert(!"frame buffer is too small for v4l2");
status = PJ_ETOOSMALL;
goto on_return;
}

So I understand that the pjmedia_frame has a "size" inferior to the v4l2 buffer, resulting to my failure. My question is simple : how can i change this setting ? I tried evetything in the sample app : changing resolution, bitrate, fps,.. I found some ressources saying to change the h264 profile level.. ok, but where do i set it ? Is it within the v4l2 manager ? or directly in the app ? How can i do it ? I played with different options in v4l2 to reduce the bitrate/resolution in order to have a small buffer, but still getting the same error.

At this point I'm completely clueless.

For info, I compiled PJsip using openh264 (no libx264) as suggested by PjSip.

Thanks for your help/ideas ;)

DaszuOne DaszuOne · Accepted Answer · 2020-03-20T11:16:30

According to your question about profile level, you can try with:

const pj_str_t codec_id = {"H264", 4};
pjmedia_vid_codec_param param;
pj_status_t status;

status = pjsua_vid_codec_get_param(&codec_id, &param);
param.dec_fmtp.param[0].name = pj_str("profile-level-id");
param.dec_fmtp.param[0].val = pj_str("42e01f");
status = pjsua_vid_codec_set_param(&codec_id, &param);

do this anywhere after pjsua_start(). Last two characters in val property are profile level. Description of levels can be found here (link). More information about h264 profile here (link).

I'm not an expert of v4l2, but have little experience with encoding video on rpi3, and I suggest you to use FFmpeg instead of pure openh264, beacuse of support of hardware acceleration (link).

Good luck!

Pjsip/Pjsua video problem : frame buffer too small

1 Answers