Keith Pratt
Forum Replies Created
-
Paulo Jan: “However, my understanding was that the deinterlacing in Compressor didn’t simply discard one field, as most crappy deinterlacers do, but did blend both fields to create the new image.”
It does interpolate, but I wasn’t necessarily meaning detail in terms of image fidelity. If the compressor treats a pair of fields as a single frame, the combing is additional detail. If Compressor or Apple’s version of H.264 is unable to compress fields separately, ‘Automatic’ will yield a larger file in its attempt to preserve the “detail”.
If you don’t want the file size to free-wheel, set a target file size.
-
Paulo Jan: “Encoded with the default H264 setting. Result: 683 Mb. Take the default setting, copy it and disable frame control, in order to prevent deinterlacing (and leave everything else the same). Result: a 854 Mb. file.”
Is that because you’re using the ‘automatic’ setting for data rate, and deinterlacing is cutting down on the resolution/detail the H.264 encoder will try to retain?
-
Wayne Carey: “Apple is sliding way behind the curve in Pro Apps development.”
Aperture and Logic are also Pro Apps, and they’re both 64-bit and certainly not lagging behind their peers.
(Just worth a mention…)
-
If your preference is to encode in Compressor, I’d recommend what Walter suggested above. Compress to a MOV in Compressor, then do a batch ‘Save As’ in MPEG Streamclip to rewrap to MP4.
Steve Eisen: “Simply change the file extension to mp4 or m4v.”
I’m not sure that that rewraps the video. I think it just changes what the OS thinks the file is and thus what it will attempt to do with it.
-
The 29.97/59.94i video may well be 24p recorded with 3:2 pulldown. Find a problematic clip and run a Reverse Telecine in Compressor, and see if it has the desired effect.
And for AVCHD clips you’ve removed from their folders, you can use Clipwrap to rewrap or transcode ready to edit.
-
Ben Holmes: “HQ bitrate is ONLY recommended for anyone using 2K frame sizes. This is based on specific technical tests done by forum leaders here (I think it was Gary, might have been Shane).”
This seems to be the biggest Chinese Whisper on the Cow.
Gary wrote an article on ProRes saying that he noticed decoding HQ was more CPU-taxing when the source files were HDV or DVCProHD. This had nothing to do with resolution but Gary’s suggestion of only using HQ for 2K and above lead some to think it was. The 2K bit seems to be what people latched on to as the message spread.
-
Shawn Bann: “The HP Dreamcolor and DSLR’s are in the same RGB colorspace.”
Where are you getting that info from?
I really like the Dreamcolor, but it’s a bit fragile for field work, doesn’t have stuff like inbuilt scopes and will only display colours accurately if fed a progressive RGB signal.
So it’s not the right display for these circumstances.
-
Chris Wright: “all web browsers use sRGB for video/images”
Safari, the latest Firefox, Chrome and IE9 all have varying levels of built-in colour management; others none at all. But that’s for images, not video. With video it’s the player plug-in or module that manages colour, isn’t it? And in that case its expectation would be Rec.601 or Rec.709, surely? Meaning you’d be least likely to run into issues with one of the two.
Chris Wright: “and again,Y′CbCr is not an absolute color space, it is a way of encoding RGB information.”
Who claimed it was?
-
Claus Frederiksen: “I have access to used/old Canon lenses from press photographer, as I want my iris to be manual.”
They’re not FD lenses are they? The advice is to steer clear of FD lenses with EOS bodies as they necessitate use of an optical adaptor.
Bob Dix: “As this camera runs at 38.5 MB/s you will need a SanDisk or equivalent CF card at 45-60MB/s UDMA for 1080P for smooth running.”
You’re mixing up MB/s and Mb/s (megabytes and megabits). Canon video runs at around 40Mb/s, which is 5MB/s.
Claus Frederiksen: ““House” and “24”in the US, is entirely shot with that camera”
It’s being used for a lot of music videos and fair bit of commercials work, but House was a one-episode test and as far as I’m aware it’s only the background plates for car shots that have been shot on DSLRs for 24. The issues with aliasing, mushiness and infrastructural limitations have stopped this generation of DSLRs from properly making it to primetime.
-
Chris Wright: “if its going to web, sRGB-EC 61966-2-1:1999 should be used/converted to so that the browser displays correctly. and wow, yea, DO NOT shoot in sRGB mode unless you’re positive you’re going to web.”
Noah Kadner: “Depends on the destination- if it’s for web use RGB, if it’s intended for broadcast use REC709.”
Gary Adcock and the makers of 5DtoRGB are saying the Canon video is full range Rec.601.
I’m also sceptical it’s best to use full range or a photo colour profile for web-destined video. Aren’t most video players expecting YCbCr?