We are looking at producing several thousand proxies from an archive and I will be thoroughly testing in the coming weeks for a proxy format that will fit our workflow.
We would like to be able to have frame accurate proxies that are around 5% the size of the full res and will give us a fully working offline workflow in Premiere CS6. We are looking at H264 for this rather than motion/photo jpeg as we need the smaller file size.
We were mostly based on FCP prior and are just making the switch to Premiere so we are wondering how well h264 will work as a native editing format.
1) Are there any considerations for the file's wrapper? I believe .MP4 would cover more windows users if used rather than .MOV, is this true? Effectively they are exactly the same but in a different wrapper? Is there an industry wide preference?
2) Would we run into any issues with long (60 mins) files encoded into H264? Frame accuracy is important as we will have users editing these proxies and then the project file will be emailed / ftp'd to another location where the full res is stored and the online edit will take place.
3) Are there any encoding tips to get better results for this type of workflow, specifically in regards to using it to edit in Premiere? We will be using Telestream Episode to encode. Is it better to have constant bit rate as opposed to variable? What about Keyframe control? Forced? Natural? Encoder profile, Main, High? If there is anything that would help the file be more accurate and efficient in Premiere?
AS mentioned I hope to have completed several tests by this week but any head start on this would be great.
We've moved most folks to mp4 for better compatibility, but not had anyone edit them.
Of course you lose true "frame accuracy" with h.264 but as long as someone checks things I would think that you are ok. (we add window burn to both confirm the TC and also to keep people from shipping something with proxy in the final.
As to encoding, test your Episode encode times. In version 6 we've seen some longer than normal encode times on h.264. (x.264 is longer still.) I'd like to see your experience. You can benchmark against the the Worker or just quicktime pro or mpeg streamclip as a test.