Lossless Transcoder for 4:2:2

Not sure how to answer this... AVCHD is 4:2:0 when it's recorded. So there is no 4:2:2 to be had. It wasn't there in the first place.

Now, you can transcode to Cineform, or perhaps some other codec, and it will synthesize a sort-of-4:2:2 for you, interpolating the missing chroma, but that's kind of the opposite of lossless (on the other side of the lossy->lossless->adding stuff line).

So -- the only way to get 4:2:2 out of an avchd camera is to record the live video stream through HDMI to a 4:2:2 recorder. But it has to be live, not after it's already been recorded in-camera.
 
DJDecay,

That's not entirely true. There are mathematically lossless codecs out there like microcosm and bitjazz. Typically you can cut the file sizes in half. Even just sticking uncompressed video into a zip file will gain you significant space. The majority of codecs, however, are either lossy, or "visually lossless," which to me is the same as lossy. Every bit must be identical for truly lossless video.
 
arrestthisman said:
DJDecay,

That's not entirely true. There are mathematically lossless codecs out there like microcosm and bitjazz. Typically you can cut the file sizes in half. Even just sticking uncompressed video into a zip file will gain you significant space. The majority of codecs, however, are either lossy, or "visually lossless," which to me is the same as lossy. Every bit must be identical for truly lossless video.
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You're absolutely right. I did not say there are not any lossless compression schemas in existence to contrast the difference. I was actually going to mention "zipping" the uncompressed file or similar to indicate. I've left out Apple Animation Codec at 100% quality setting as well.

Only reason why I skipped it subliminaly, is AVCHD in its most typical form ships interlaced, most of these non-loss schemas are progressive or full frame based aside from SheerVideo - And the typical transcode is going to be into ProRes422 as nothing else is available on ingest in FCP.

I guess the most optimal answer would be - Transcode to SheerVideo 4:2:2 using the best 4:2:0 to 4:2:2 estimation/interpolation algorithm possible (Synchromy) comes to mind. - Having not used it , I did not make a recommendation, it could break the mans FCP setup for all I know.
 
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" I was actually going to mention "zipping" the uncompressed file or similar to indicate."

Great minds think alike. Lol.

I've actually found 4:2:0 to 4:2:2 to be quite good, whether just the basic FCP pro res conversion in log and transfer, or something more advanced like cineform NEO.

I think this is because all the 4:2:2 footage I've worked with was recorded in a pre-filter type codec. (E.g. DVCPRO HD.) AVCHD being full raster at PH without interlacing, is well equipped for conversion to 4:2:2. However a full raster 4:2:2 codec like AVC-Intra would likely look better... whether it would take pixel-peeping to see the difference. I don't know.

So to the OP, I guess my answer would be that lossless encoding is really not relevant to 4:2:2 chroma. Of course lossless codecs will look better, but chroma subsampling is only one aspect of quality, and chroma subsampling can exist in heavy compression or none. You could have an uncompressed 4:1:1 sampled codec. Going to lossless will not interpolate any new information. Cineform claims to interpolate chroma, so if you're looking to get closer to 4:2:2 from a 4:2:0 source, assuming their claims are valid, that would be your best bet. But the result will be a transcode into a lossy codec. The idea is that you can have a lossy codec that looks great. How lossy it Looks is the most important question aside from CC/compositing concerns.

Cheers! and happy Halloween
 
arrestthisman said:
" I was actually going to mention "zipping" the uncompressed file or similar to indicate."

Great minds think alike. Lol.

I've actually found 4:2:0 to 4:2:2 to be quite good, whether just the basic FCP pro res conversion in log and transfer, or something more advanced like cineform NEO.

I think this is because all the 4:2:2 footage I've worked with was recorded in a pre-filter type codec. (E.g. DVCPRO HD.) AVCHD being full raster at PH without interlacing, is well equipped for conversion to 4:2:2. However a full raster 4:2:2 codec like AVC-Intra would likely look better... whether it would take pixel-peeping to see the difference. I don't know.

So to the OP, I guess my answer would be that lossless encoding is really not relevant to 4:2:2 chroma. Of course lossless codecs will look better, but chroma subsampling is only one aspect of quality, and chroma subsampling can exist in heavy compression or none. You could have an uncompressed 4:1:1 sampled codec. Going to lossless will not interpolate any new information. Cineform claims to interpolate chroma, so if you're looking to get closer to 4:2:2 from a 4:2:0 source, assuming their claims are valid, that would be your best bet. But the result will be a transcode into a lossy codec. The idea is that you can have a lossy codec that looks great. How lossy it Looks is the most important question aside from CC/compositing concerns.

Cheers! and happy Halloween
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I guess my question is really, what is the highest quality workflow possible with AVCHD? Would it be to wait for NLEs to perform effienctly working with the native codec, or to transcode to 4:2:2 with Cineform NEO, or something else?
 
What are you trying to do with AVCHD? Is it straight cuts type stuff? Or are you going to be doing heavy color correction and effects type stuff in post?
 
Mike Harvey said:
What are you trying to do with AVCHD? Is it straight cuts type stuff? Or are you going to be doing heavy color correction and effects type stuff in post?
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Mostly straight cuts type stuff I would guess. The reason I say "I would guess" is that I am a wedding photographer and I am going into video. Not cheap photo/video packages, but rather high quality photography or video, not both. So, where I will end up as far as heavy color correction and effects type stuff goes, I just don't know yet.
 
I edit the native avchd files because I assume that is the best quality.
Is this correct or would transcoding to something like cineform result in a better picture?
I'm not too concerned with the time it takes as long as I can get the best image with the least amount of artifacts.
Mostly I do straight cuts and minimal color correction, the only type of graphics are text titles.
 
I was just reading the instructions for the EDIUS Neo 2 Software and I believe it has a transcoder. Does anyone know what it transcodes to?
 
About the same as DVCProHD is it not? 1440x1080?

DNxHD would probably be better but trying to find a user friendly & free transcoder to get it there is probably harder than finding the holy grail.

BTW, what I think he meant by "lossless" was a codec that wouldn't lose even more info than the original codec already has. Or at least as min an amount as possible. (Usually for FX work).
 
Denwa said:
DNxHD would probably be better but trying to find a user friendly & free transcoder to get it there is probably harder than finding the holy grail.
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Depends on what you're editing on. I had it installed on my PC, and Adobe CS4 had no issues with it, either editing or exporting.
 
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