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File sometimes not playing


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I'm having trouble with a file not playing. It just doesn't show up. Just black. I have a file that plays through the whole movie with the timeline running. At the end of the movie I want to crossfade into another movie the loops so I have that one set to free running and loop. Sometimes it shows up sometimes it doesn't. It's running on a watchpax that is driving 2 projectors edge blended. The file is mpeg2 1920x960. Any ideas? 

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Is that per output or one movie for both outputs?


Sounds like running the two movies at the same time

are just over the WATCHPAX performance threshold.


BTW mpeg2 movies with B frames require much more processing power than the same movie with no B frames.

Had a museum install with the same description - movie played sometimes, failed to play (black hole) sometimes.

Eliminated B frames while keeping all other parameters the same and the problem was resolved.

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Using all I-frames is usually a bad idea, unless you need to jump around the movie very quickly. All I-frame encoding needs a much higher bit rate to achieve the same quality. If I understand AME correctly, N-frames is the number of frames between I-frames, which is the same as the key-frame interval. Normally, 1-2 I-frames per second is a good compromise between quality and performance, which translates to setting N-frames to 15-30 for a 30 fps movie. Longer I-frame intervals can in some cases produce the "pumping" artefacts. M-frames is the number of B-frames between consecutive I- and P-frames, so I would assume setting this to 0 would eliminate the B-frames. Eliminating B-frames greatly reduces the (CPU/GPU and memory) load of the decoder. The price you have to pay is slightly less compression (if encoding with constant quality) or a slight reduction in quality in case you are encoding with constant bitrate. If you are worried about the quality, just bump up the bitrate by 10% as compared to when encoding with B-frames. 



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