I don't know anything about video, but my camera takes it and I need to figure out how to produce the stuff. I'm sure this information's out there somewhere, but I've been unable to find it, so here's what I found.
The Problem
Adobe Premier Elements will read Canon's 5D MK 2 files right out of the box, and they render fine on output from there. The catch is that they're horrible to preview in the editor; one way or another my machine isn't up to it. Checking the manuals and then Googling around, there's a lot of information out there, but most of it is not very high quality. The 5D MKII uses a H.264 codec to code the video stream. This is wrapped with an Apple Quicktime header with file extension of MOV. This is all visible from within a video editing or viewing program. The video's 1920 by 1080 pixels, 30fps (although people argue over that). There's also an audio track in the file.
The problem then is that on my machine the preview within Premier is slow; I don't have enough hardware or software horse-power to decode and replay that H.264 stream in real time. If I render the video, the final result (in whatever format I choose) is fine, but editing's not much fun with choppy video.
There are two solutions people use to this, either:
- edit using easier to process proxy files and then swap the real files in before the final render; or
- transcode to a format which is easier for the editor to process.
I don't much like the first option as I think it helps to see and manipulate images full size; I don't see how you can tell it's really sharp if you're not looking at it at 100%.
Transcoding
Looking at the second option then, the question is what format to use. The wrapper is presumably not hugely important, as the editor can either read it or not. I chose AVI because that's a windows-specific format and I'm using a Vista machine. MPEG Streamclip is the mutts nuts of free transcoders for Windows, and it presents a long list of options for codecs in AVI files. I just tried most of these to see which would work on my system. There results were as follows...
Won't play back acceptably in VLC
- H.264 - no video, audio ok
- Apple Component Video - YUV422 - audio only
- Jpeg 2000 / 50% - audio only
- Apple DVC Pro - squashed video
- Apple Photo Jpeg/ 100% - jerky playback
- H.261 - tiny
- H.263 - tiny
Don't play in Premier
- Apple MPEG4 compressor/ 50% 3M - audio only
- Apple MPEG4 compressor/ 100% 40M - audio only
Play in VLC and Premier
- Apple Cinepak/100% - ok 37M
- Apple Photo Jpeg/ 50% 27M
So that's the choice; nothing else seems to work. Looking at the files in both VLC and Premier, I prefer the photo Jpeg compression marginally - the blacks are blacker than those in the Cinepak codec. I'm using a calibrated monitor but I can't examine the histograms for the video.
Either of these formats preview in Premier marginally better than the original MOV files, but neither's what I'd really want to see. I think more experimentation is required here.
Colour Management
One possible criterion for choosing a codec would be colour management; they do render slightly differently, and on a calibrated system like mine that's usually signs of some colour management problem.
First I tested Premier Elements. The PS/CS series is colour managed, so I'd expected this to be so too. The bad news is that it appears not to be: if I import a still image in sRGB it isn't rendered correctly, which the standard says it should be even in the absense of an embedded profile. So the editing tool colours are going to be off... how about playback? No soap with VLC either; that's not colour managed.
Wally stopper: I just need the application to render the video using my calibrated monitor's profile, so the colours are correct. See here for the basics on this.
Premiere Pro CS4
And then I got hold of a copy of Premier Pro CS4 and the above transcodings don't seem to work for this, which is weird but there it is. Thanks to a bit of googling, I found that it all works well if I use the Adobe Media Encoder, which works kind of like Streamclip, with the following settings:
- Format: MPEG2
- Preset: HDTV 29.97 High Quality
- Everything else default except: progressive, drop frame, quality 4, VBR, two pass, minimum bit rate 25, target 39
That keeps the file size about the same and looks ok.