The current “release” v002 Movie Player 2 has terrible performance. Neither of us have the time to fix it right now.
A Syphon-serving movie app is a sound idea. The v002 Movie Player 2 spawns another process and uses the same mechanism as Syphon (IOSurface) to send the video to QC. Apple’s QC player does that too.
If you are able to use codecs supported by AVFoundation – H.264, ProRes and Photo-JPEG I think are the current list – then that is by far the simplest route to take, and very fast.
The maximum frame dimensions Syphon supports is dependent on the GPU. If you’re careful about how you feed your frames to Syphon it needn’t add any further performance hit.
If you let us know if you can work with AVFoundation or not we can probably give you pointers to the most efficient route to send frames through Syphon (if you need them).