Hello!
I am facing a video quality problem: the video transcoded by wowza transcoder addon seems to have lots of artifact expecially in fast scenes.
Below some configuration information.
Input stream: 1100 kbps h264 baseline profile at 1024x756 25fps with 64 kbps aac audio . No additional information because we don’t control the encoder streaming to wowza. I know the resolution is too higth, and in the next days it will be step down to 720x404.
OutPut stream:
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1100 kbps Video h264 baseline + 64 audio aac. 25fps. Res 1024xfit-width. Key Frame every 100 frame
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720 kbps Video h264 baseline + 64 audio aac. 25fps. Res 640xfit-width. Key Frame every 100 frame
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440 kbps Video h264 baseline + 64 audio aac. 25fps. Res 512xfit-width. Key Frame every 100 frame
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180 kbps Video h264 baseline + 64 audio aac. 25fps. Res 256xfit-width. Key Frame every 100 frame
Cpu average load about 45%, maximun load 65%.
Wowza Version 3.1.2 running on ubuntu 12.04 in ec2.
The output video is available to clients with HDS, HLS and Smooth Streaming Protocol. RTMP and rtsp is available for debug purpose.
All http streaming video reproduced presents lots of artifact like patchwork. I have taken some screen shot.
To debug purpose I’ve tested deeply single 1200 transcoded bitrate. I’ve tested quickly also the others bitrate, and the behaviour is the same of 1200 one.
This is what I noticed:
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Rtmp input stream. The video reproduced with flash player is ok. I dump to file the stream with ffmepg option -c copy ( no transcoding by ffmpeg ). The recorded file has NO artifacts.
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HLS 1200 transcoded stream. Video reproduced with VLC and IOS devices presents artifacts. I dump to file stream with ffmpeg with option -c copy. The recorded file presents artifacts.
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HDS 1200 transcoded stream. Video reproduced with OSMF Flash player presents artifacts.
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Smooth Streaming 1200 transcoded stream. Video reproduced with silverlight player presents artifacts
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1200 stream rtmp. The video reproduced with flash shows NO artifacts. I dump to file the stream with ffmpeg with option -c copy. The recorded file presents NO artifacts.
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1200 stream rtsp. The video reproduced with VLC presents NO artifacts.