[Live-devel] Streaming H264 elementary stream vs file

[Simon Brown]

On Sep 8, 2020, at 12:52 AM, Simon Brown <sbrown at microvideo.co.uk> wrote:
>> If I take our transport stream and convert it to raw H264 using FFmpeg with this command line:
>>
>>   ffmpeg -i udp://:61110 -c:v copy -an -f h264 test.264
>>
>> and then ask testOnDemandRTSPServer to play it by asking for rtsp://192.168.1.13/h264ESVideoTest
>>
>> it plays fine.
>>
>> However, if I change the ffmpeg command to pipe out the raw 264 data, and then the RTSP server to accept stdin as the file for h264ESVideoTest I get a single frame displayed and nothing more. Is there any reason for this?
> Well, I’m sure there’s a reason for it; I just don’t know what that reason is :-)
>
> I assume that you’ve already successfully tested:
> 	your-modified-testOnDemandRTSPServer < test.264
>
Thanks - I asked for that.  Yes, I have successfully tested that.  It plays fine.  One thing that puzzled me though, is that if I ask for the stream again it can start again at the beginning?
I guess my understanding of pipes is poor, because I'd have thought that if it's taken the file in, it can't read it a second time.
I'll try and record the stream with openRTSP in both instances and see what the difference is.

Simon
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