[Live-devel] Problem with receiving RTSP from Antrica ANT-35000

[Ben Willcox]

Hi,

I've been using openRTSP for several years in my application, receiving 
an rtsp stream from Axis video encoders and Axis IP cameras and saving 
to disk. I'm doing some trials with a new video encoder, an Antrica 
ANT-35000 which is an HD encoder (unlike the Axis ones which are 640x480 
max).

I've come across a strange problem when capturing the rtsp stream from 
this using openRTSP (v2014.11.12) whereby every time a keyframe is 
encountered the video freezes for a couple of frames (playing back in 
VLC). If I play back frame by frame in Avidemux I get an error in the 
console every 30 frames (the I-frame interval set in the encoder) and 
the picture does not update for 2 frames:

------------
[lavc] error in FFMP43/mpeg4!
[lavc] Err: -1, size:9

Editor: Last Decoding2 failed for frame 63
[lavc] no frame!
------------

The command I'm running is:
openRTSP -4 -n -t -Q -w 1920 -h 1080 -b300000 rtsp://<ip address>/video1 
 > testfile.mp4

(basically the same I've been using with the Axis cams but a larger 
buffer size).

If I use VLC to capture the rtsp stream and save to disk, this then 
plays back without any problems and is smooth so I'm not quite sure what 
is going on.
Any ideas on where I should look to solve the problem?

Thanks,
Ben