iOS Stutter from RTP Live Stream

[Brian_Walker]

Hello,

I am using a LEADTools encoder to encode a Live stream and send the output via UDP to a WOWZA server. The stream looks great wen played back on the RTSP protocol however it the video stutters when played back on the iOS http. This is on both an iPod and an iPad. I have tried this with the network running normally and also with the iOS device as the only thing on the internal network. The stream itself is a 40k AAC audio stream which is nice and smooth through the majority of the playback with an occasional stop in it. The video is H264 encoded at around 500k and all motion in it stutters. I downloaded and ran the Media validator tool from Apple and it appears that as the stream is being pulled I am getting 404 responses from WOWZA.

We are running this on a windows 2008 virtual server running at a web hosting company. The machine itself claims single core and 2gigs of ram but I am not seeing any extreme resource usage.

Does anyone have any ideas? Any help would be great appreciated.

Thank you.

[Richard_Lanham]

Take a look at this article

https://www.wowza.com/docs/how-to-configure-apple-hls-packetization-cupertinostreaming)

If your key frame frequency is something other than a factor of 10, you can adjust cupertinoChunkDurationTarget. Or use the default cupertionChunkDurationTarget and adjust key frame frequency, try 2 seconds

And see if bitrate is a factor, try reducing bitrate by half to see if it makes any difference.

Richard

[Richard_Lanham]

First, I would get the default Cupertino settings back, or remove them, and try with lower bitrate. Then reset to the the default Cupertino settings and focus on cupertinoChunkDurationTarget and key frame frequency of your stream. As described in the article, the key frame frequency should be a factor of cupertinoChunkDurationTarget.

Richard

[Brian_Walker]

Yeah I have gone through that setup and just to try again I adjusted the MaxChunk back to ten and the PlaylistChunkCount to 5. That seems to have resolved the 404 in the middle of the stream however the video is still as choppy as ever. I have the i-Frame creation set to approximately 2.5 seconds and again the video looks great coming in from the rtsp broadcast from wowza it is just the iOS http chunk that is making it look choppy.

[Brian_Walker]

Even at half the bitrate it still stutters. I am only running at 500K and I tested at 250K.