Canon 7D in FCP – Codec transcoding?

[Paul Jay]

Composting/Editing with H264 will give you loads of crap sooner or later.
I’ve seen H264 performance in CS5 and it’s pretty good, but you can do so much more with i-frame codecs. Even in Premiere.
I-frame codecs are far more reliable and give faster rendering in a production pipeline.

[Dennis Radeke]

[Rafael Amador] “”QuickTime isn’t 64 bit…….Adobe seems to have worked around the problem by spinning off a 32 bit thread for QuickTime support so you lose that Mercury Engine goodness”.”

Well, I took this and forwarded it to one of the GPU engineers at Adobe to actually get the scoop on this. I’ve read Philip’s entries with a lot of interest and he seems like a terrific person.

Nevertheless, Philip’s statement is his thoughts or supposition and not necessarily what is going on. Below is essentially a cut and paste from the email response I received from one of the GPU engineers actually writing the code on Premiere Pro’s Mercury Engine (the GPU part anyway)…

“It is true that the QuickTime libraries provided by Apple are not 64-bit and we spin off a 32-bit helper process to talk to QuickTime. The slowest piece of this is QuickTime itself and it simply cannot deliver frames fast enough for many formats.

To work around this we have written our own QuickTime parsing library and where possible handle the QuickTime files with our native codecs as we would for other file types. We have made this work for what we have judged to be the most important QuickTime files, as an example this is how we achieve good performance for Canon 5D footage, which are QuickTime files. There are some limitations to this, if we do not have native support for the codec (such as ProRes) we cannot use this native path and have to talk to the out of process 32-bit QuickTime server.

Beyond that the Mercury Playback Engine still can provide plenty of other benefits when using QuickTime files. Despite the QuickTime process being 32-bit, we immediately bring all frames into the main 64-bit process so we can continue taking full advantage of a 64-bit address space. While QuickTime is single threaded, once the frames are brought into the main process we will render and apply effects on multiple threads taking full advantage of all cores using technologies like Apple’s Grand Central Dispatch. Also if a CUDA card is present all supported rendering and effects will be moved to the GPU. This can lessen the CPU load allowing more time for decoding. Even if the performance of the QuickTime files in this setup isn’t great, having a CUDA card will allow adding many effects essentially for free.”

I’ll use this as an opportunity to mention again that MPE is in fact 3 distinct features and not just GPU: 64-bit native code, 64-bit memory addressing and the GPU goodness. Everyone is getting two of the three when using CS5.

Again, to reiterate – this is meant to give clarification around Premiere Pro, Quicktime and GPU interaction

[Dennis Radeke]

[Michael Gissing] “Just curious Dennis. In the past, did FCP fanboys hang around the Premiere Pro forum and snipe from the sidelines? I am wondering if your constant reminders of just how great CS5 has become, are payback for someone’s previous indiscretions on y8ou8r favoured boards?”

Definitely not Michael and I try to go out of my way to be as straightforward and honest as I can be. My goal is to be a part of the community and address questions that may come up with Adobe – whether with FCP or by itself. Am I passionate about my products – only as much as many are with other creative products such as FCP – in short – most definitely.

My honest apologies to you and any who feel I am ‘sniping’

[Michael Gissing]

[Dennis Radeke] ” My goal is to be a part of the community and address questions that may come up with Adobe – whether with FCP or by itself.”

Not only did this post make no mention of Adobe until you posted, Shane also pointed out that the post was about what was best to do with FCP, which the OP specifically asked about.

I don’t want you to apologize and think it OK to keep doing the CS5 sales routine from within this forum. By all means sing the praises on the appropriate forum. I am more than happy to read what you contribute to the debate in the appropriate place. I just don’t think it appropriate to bloat threads here with posts about CS5 when posters are not specifically asking about comparative features. I can’t spruik my commercial services on this forum so what gives you the right to?

[Rafael Amador]

Hi dennis,
Thanks for this info.
Many of those topics are mostly related with programming and some times I get lost.
rafael

http://www.nagavideo.com

[George Monteiro]

You Seem to be very knowledgeable on FCP. I have a similar issue, several hours of 5D & 7D raw footage for a single 30 second spot. Rather than transcode all that raw footage, what happens if if I do a rough cut on H.264 timeline and drag the clips or the entire timeline into a Prores timeline and render it out will the transcoding done in the renderer be as good as if I went back and transcoded the raw files first?

Secondly the H.264 timeline plays back fine on my computer screen but chokes going through my BlackMagic Multibridge Pro box. Is that because it can’t process the H.264 output of the timeline in real time?

Thanks