Following on from my article last week on Issues With Video In Pro Tools, I came across a post I had forgotten about, to do with which video codec is best to use with Pro Tools, and my notes took me back to post on the DUC about using mp4 codecs on Pro Tools.
Essentially, I’ve been working with DV video for all of my mixes. (Longform shows.) I’m not getting stuff from out of town clients and converting from MP4 back to DV with Streamclip. Works OK, but seems to soften sync even more. I’ve tried importing the MP4 directly, but it’s always sluggish and choppy. My system runs flawlessly with DV. Any recommendations of a spec for an MP4 delivery that might work without converting to DV, or is this an “it is what it is” situation?
Our good friend Tamas Dragon suggested…
Although it is not mp4, try this. Less taxing on cpu, good picture quality.
Frank Kruse responded… (this is updated info from Frank rather than the original post. Thanks Frank for the update.)
DNxHD36 is around 4GB per reel (not 20GB) at 1080P so about the same size of DV PAL while offering a vastly better quality, So the 100GB/Film info was wrong which makes DNxHD36 an even better option. It’s about 1/5th in size compared to ProRes while having the same perceived quality.
MP4, H264, MPEG2 etc. are all intra-frame codecs that do not store every single frame in the stream. The decoder has to generate the frames in between from the stored delta-information. As a result it´s very CPU-hungry and not ideal for things like scrubbing etc. Which is why these codecs are not used as working formats in pro-video. They are mainly for delivery and streaming etc. where all is about reducing bandwidth. Having said that you CAN use H264 directly in PT on a fast mac but it´s not ideal when you want to save all processing power for audio.
So unless you have got a fast computer, probably better to stay away from mp4s etc. But if you do go for mp4/H264 then make sure it is ‘keyed every frame’ and ask for this from the picture editor.
The updated info from Frank makes the DNxHD36 codecs a serious contender to use in the workflow espcialy if coming form an Avid system.
All of this also got a number of suggestions for using photojpeg codec as well as a number of shoutouts for the free MPEG Streamclip app for Mac or Windows from the guys at Squared 5 which I find so useful for all sorts of video transcoding applications.
You can download the Avid DNxHD36 from here, and do as Tamas does and use MPEG Streamclip to convert incoming content to them.
What is your preferred workflow? What flavour of video at what resolution do your prefer? A lot don’t seem to feel that HD is essential for audio post work whilst others swear by it. Please do share your experiences….
Frank Kruse very kindly sent an email with an update on the file sizes that are created by the DNxHD36 codec which makes it even more appealing so I have updated the body of the post to reflect Frank’s revisions. Thanks again Frank.