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  1. Member
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    I have a lot of AVCHD footage that needs to be converted to raw (v210) so I can use it in Premiere Pro. (This process will bypass Premiere Pro's AVCHD chroma bug, which apparently persists even in CS5.) My current difficulty centers once again on Rec 601 vs. Rec 709. Specifically, I do not have a way of testing whether my raw renders are maintaining their original color or are instead undergoing a bad color conversion.

    FFVideoSource("file.MTS")

    That's my script. VirtualDub with Fast Recompress is what I use to make the v210 raws. Here's the confusing part:

    FFVideoSource("file.MTS") -> VDub preview = dark reds, bright greens.
    file.MTS -> PPro preview = dark reds, bright greens.
    FFVideoSource("file.MTS") -> VDub's v210 output -> VDub preview = dark reds, bright greens.
    FFVideoSource("file.MTS") -> VDub's v210 output -> PPro preview = bright reds, dark greens.
    FFVideoSource("file.MTS") -> VDub's YV12 output -> VDub preview = dark reds, bright greens.
    FFVideoSource("file.MTS") -> VDub's YV12 output -> PPro preview = bright reds, dark greens.
    file.MTS -> PPro v210 output -> VDub preview = dark reds, bright greens.
    file.MTS -> PPro v210 output -> PPro preview = dark reds, bright greens.
    file.MTS -> The KM Player (CCCP) = bright reds, dark greens.

    I hope I can be forgiven if this set of data offers only confusion. Some of the results do not jive with what I have come to (or been told to) expect from these applications. Therefore I aim to simplify matters. All I need is a 1- or 2-frame video which has a test pattern or similar means of gauging whether the video is being displayed with correct colors. I should be able to make some accurate guesses with such a video in hand. I hesitate to make a guess based on the results I've outlined.
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  2. An AVC/AC3 TS file with alternating BT.709 and unflagged video:
    http://www.cypheros.de/files/Testbild_colour_description_alternating_120sec.ts

    Note that VirtualDub always converts YUV to RGB with the BT.601 color matrix.
    Last edited by jagabo; 18th Jun 2011 at 21:38.
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    Originally Posted by jagabo View Post
    An AVC/AC3 TS file with alternating BT.709 and unflagged video:
    http://www.cypheros.de/files/Testbild_colour_description_alternating_120sec.ts
    Thanks. That was quick.

    Originally Posted by jagabo View Post
    Note that VirtualDub always converts YUV to RGB with the BT.601 color matrix.
    So the surprising result is that 1) VirtualDub was getting it wrong, and 2) Premiere Pro apparently handles HD YV12 correctly, and so isn't limited to v210 in this regard.

    Useful information going forward.

    Edit: I'm also more than a little surprised that a regular media codec was also getting it right.
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  4. Nice testing. I have to apologize.

    I told you out of various common lossless intermediates, only v210 gets rec709 treatment in PP, but I can confirm your observation that uncompressed YV12 out of vdub does too.

    I swear this behaviour must have changed. Like you , I did a zillion tests a while back when my OCD wasn't in remission yet I posted a bunch of results on Doom9 and here with PP and vegas along with chroma upsampling testing

    But one reason you might not want to use uncompressed YV12, is superbrights/darks aren't retained, but they are in v210. But you still have the option to "legalize" them before converting . Also, you might not want to allow PP to upsample 4:2:0.
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    Originally Posted by poisondeathray View Post
    Nice testing. I have to apologize.
    No need. My projects have flowed quite smoothly thanks to help from folks like yourself. I am perfectly familiar with the phenomenon of the unanticipated. (Thanks in large part to Premiere Pro, it must be said.)

    Originally Posted by poisondeathray View Post
    But one reason you might not want to use uncompressed YV12, is superbrights/darks aren't retained, but they are in v210. But you still have the option to "legalize" them before converting . Also, you might not want to allow PP to upsample 4:2:0.
    Right. The YV12 test (actually, just what it was defaulting to with "uncompressed RGB/YCbCr") was just my stab at giving myself more data to work with. As for legalizing them before importing to PPro, I might. But it can't be denied that a GUI makes such things quicker, and Fast Color Corrector seems to do a fine job within the limited scope of my needs.
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  6. Originally Posted by poisondeathray View Post
    I told you out of various common lossless intermediates, only v210 gets rec709 treatment in PP, but I can confirm your observation that uncompressed YV12 out of vdub does too.

    I swear this behaviour must have changed.
    Maybe it's resolution dependent? A lot of programs assume rec601 for SD and rec709 for HD if the matrix isn't flagged.
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