GH2 transcode with 5D2RGB

Phil Rhodes said:
There is a small - in my view insignificant - colour shift. That's probably fixable in the coefficient designer.
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That's correct, and in fact 5DtoRGB is unique in that it allows for a user-defined decoding matrix to be used. So, if you're unhappy with the colors in your transcoding result, you can re-transcode using a different matrix. You're not just limited to BT.601 or BT.709.
 
Phil Rhodes said:
The only thing - absolutely the only thing - that compression helps with is disk bandwidth. In absolutely every other way, it's nothing but bad.
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You and I are in complete agreement about this. As I mentioned in my lengthy Cinema5D post (read it here), this is absolutely true and only a workaround to not being able to physically pack a disk array into a DSLR (or any camera, really). However, this will be solved at some point which will make the whole codec discussion moot, at least for capture / acquisition. Delivery formats will probably still be compressed, but this is much less of an issue for delivery than for acquisition, which must be dragged through the entire post process.
 
Is Cineform better than ProRes, even ProRes HQ at 220 Mbit/s (without mention ProRes 4444) ?
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Cineform is a codec using the discrete wavelet transform; ProRes is a codec using the discrete cosine transform. Wavelets are too often presented as a panacea to all compression problems and it is not a perfect approach - it is particularly susceptible to looking like absolute crap while simultaneously achieving incredibly high mathematical signal to noise ratio, so people can claim it's great on paper while actually producing fairly feeble-looking results. However, it's generally true that wavelets provide better performance for the bitrate than cosines, at the expense of being much more hard work for the host CPU.

Cineform should (frankly, will) outperform ProRes at similar bitrates, but you'll probably need a bigger computer. At that point, my natural reaction is to work uncompressed as disk bandwidth is cheaper than CPU clock speed.

P
 
After more testing i really think 5DtoRGB is superb. Thanks for that, Thomas.

Despite the warnings for cameras other than the 5D, it performs flawlessly, apart from interpreting the frame rate, which is exported as double the speed.

Is there a way to add a "don't display this warning" for GH1 footage, as it is quite a lot of clicking to get past the warning for every file it decodes.
 
Again, it's my understanding that there will be. There's already quite successful commandline versions which can be trivially scripted to process many files.
 
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htinla said:
Is there any way to use 5DtoRGB for batch processing?
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There is a script using terminal on the mac for this. I haven't used it but I imagine it works well. Only problem with 5D2RGB is that GH1 loses the sound. I guess you can work around this but it's not as elegant as putting Canon stuff through it. It really does encode way better than native FCP import in my opinion. Unfortunately there was an option in an earlier build to add noise to the file pre encoding. This did a nice job of getting rid of banding on flat featureless surfaces and graduated things like skies. I still have that version so I can still have that option if needed.
http://www.noside.fr/5dtorgb-batch/
 
johnnym said:
Despite the warnings for cameras other than the 5D, it performs flawlessly, apart from interpreting the frame rate, which is exported as double the speed.
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Yeah, that's something that can be fixed with Cinema Tools in the mean time. I'll address this in the next version.

Is there a way to add a "don't display this warning" for GH1 footage, as it is quite a lot of clicking to get past the warning for every file it decodes.
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Yeah. I haven't gotten any reports of corruption or anything, so it seems that would be safe. I'll remove it in the next version.
 
I'm trying to understand what is being talked about here....

This is a utility that allows you transcode GH2 footage so that it has a matching color matrix to 5Dmkii footage? Does this affect the contrast curve in any way? My biggest complaint right now is how much more contrasty, crushed, crunchy the GH2 looks even when made to be more neutral w/ the in camera settings that any of the nice creamy 5Dmkii, 7D or 60D videos I have seen. Would we get an image that appears very very similar or identical in this way?
 
5dtorgb is an application that allows for very high quality transcoding from a camera's compressed avchd/h.264 implementation into a post-production optimized format.

YOU have control over the results.

By the way - it sounds like you are having gamma issues.
Expose to the right of your histogram without clipping for a "creamier" look. Cinema and smoothe picture profiles are your friend.
 
Thomas Worth said:
Yeah, that's something that can be fixed with Cinema Tools in the mean time. I'll address this in the next version.


Yeah. I haven't gotten any reports of corruption or anything, so it seems that would be safe. I'll remove it in the next version.
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Thanks Thomas. Much appreciated. I'm quite fond of my better looking footage.
 
Phil Rhodes said:
I'm campaigning to get the diffusion dithering back in, especially for 10-bit output.
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This is more of a possibility now since the new engine will be GPU-optimized. The previous noise feature was very basic, with no control over grain/noise size, etc. For this to really look good, it needs to be implemented using a proper noise algorithm (which can be extremely slow).
 
Does anybody who has tested it, could show us footage or screen grab please. Lot of excitement but nothing to look at. The Canon image where so soft from the start that the 5d2rgb made a lot of sense, but what would be the case for the gh2 superior detailed image already. Will it show some good to dramatic improvement.
 
It's not really about sharpness, it's about the chroma upsampling - the 5D example I posed shows that very clearly with the red lips. The GH series will have the same issue. If someone wants to send me a link to a nice, sharp, well-exposed GH-originated file with some good colour contrast in it (such as a Macbeth chart) I'll happily run a test.

P
 
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