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Yellow_ · 23rd November 2011, 14:08

I was referring to the histograms in that thread due to incorrect handling of luma in conversion to RGB not the fact that particular release of FFMS2 was buggy, give me some credit to blame that on a lossless codec would be idiotic.

What this comes down to is implementation of the codec for example, if you convert h264AVC to huffyuv lossless codec with ffmpeg stable or from git on the CLI as many do as it's the quickest way, it squeezes luma, that's not lossless. Convert h264AVC to utcodec with ffmpeg on the CLI and it squeezes luma that's not lossless. :-)

You can get a binary here: http://ffmpeg.zeranoe.com/builds/ many converters and batch scripts out there use ffmpeg CLI so it's not some odd behavior from one particular converter application. Try it on huffyuv or utcodecs.

However you show that using a system wide implementation of the lagrith codec, (not available in ffmpeg) accessed via Virtualdub there is no squeezing. Jolly good, now perhaps try that with a lossless codec like utcodec or huffyuv. What do you see? I see luma squeeze. :-)

Going back to my initial comment to the OP, I merely suggested to the OP that as he'd mentioned lossless codecs and the thread title is correct handling of AVC then not to assume using lossless codec was without error and in fact COULD BE NOT lossless. :-)

Meta data is not my problem as I explained, I'm aware of it.

I's not necessarily the case that the OP was aware of the loss of matrix info and for Avisynth dwellers who are aware, are they lining up with smug comments about I need to deal with it, no because the comment was for the OP. As I'd mentioned in the initial comment the loss of matrix and luma squeeze with certain lossless codecs I obviously am aware of it don't you think?

I was under the impression that a forum was to help people who need help, those in the know don't need to reply with smug answers.

And again your bitrate comment, is a smug misrepresentation of what I said.

That's the last I have to say, feel free to churn it out some more if you feel the need.

23rd November 2011, 14:08	#13 \| Link
Yellow_ Registered User Join Date: Sep 2009 Posts: 378	I was referring to the histograms in that thread due to incorrect handling of luma in conversion to RGB not the fact that particular release of FFMS2 was buggy, give me some credit to blame that on a lossless codec would be idiotic. What this comes down to is implementation of the codec for example, if you convert h264AVC to huffyuv lossless codec with ffmpeg stable or from git on the CLI as many do as it's the quickest way, it squeezes luma, that's not lossless. Convert h264AVC to utcodec with ffmpeg on the CLI and it squeezes luma that's not lossless. :-) You can get a binary here: http://ffmpeg.zeranoe.com/builds/ many converters and batch scripts out there use ffmpeg CLI so it's not some odd behavior from one particular converter application. Try it on huffyuv or utcodecs. However you show that using a system wide implementation of the lagrith codec, (not available in ffmpeg) accessed via Virtualdub there is no squeezing. Jolly good, now perhaps try that with a lossless codec like utcodec or huffyuv. What do you see? I see luma squeeze. :-) Going back to my initial comment to the OP, I merely suggested to the OP that as he'd mentioned lossless codecs and the thread title is correct handling of AVC then not to assume using lossless codec was without error and in fact COULD BE NOT lossless. :-) Meta data is not my problem as I explained, I'm aware of it. I's not necessarily the case that the OP was aware of the loss of matrix info and for Avisynth dwellers who are aware, are they lining up with smug comments about I need to deal with it, no because the comment was for the OP. As I'd mentioned in the initial comment the loss of matrix and luma squeeze with certain lossless codecs I obviously am aware of it don't you think? I was under the impression that a forum was to help people who need help, those in the know don't need to reply with smug answers. And again your bitrate comment, is a smug misrepresentation of what I said. That's the last I have to say, feel free to churn it out some more if you feel the need. Last edited by Yellow_; 23rd November 2011 at 14:17.