Lagarith vs HuffYUV, archiving and file size

[Kereellis]

Have you tried to run a comparison test with compressions through vdub as well?

When I decompress a YUY2 using the same colorspace settings das escribed, the file size between the original and huffyuv-decompressed YUY2 is different (just by a few kb), and cdcheck indicates there's a content mismatch, in line with what I'd expect based on my screenshot comparisons (audio was direct stream copy, no interleaving options etc.).

EDIT: Alright so the content mismatch/ file size differences was apparently due to the audio after all, which does strike me as weird since I used direct stream copy and made sure there was no offset or interleaving. Audio disabled, the actual file size reported by windows explorer was the same.

There is now a 99% match between the files. This may as well be because cdcheck also checks the creation/modification date, which is different for both files, and it seems to round down to wholes. I assume that if there's really a colorspace conversion involved, the difference would be larger.

Then again, I'd still be curious about what your findings would be regarding huffyuv conversion in vdub. Likely's after all do not eliminate all doubt about my workflow.

[poisondeathray]

I've run a bunch of tests in vdub as well as avisynth and other programs . It's fine in vdub if you use "fast recompress" mode (which you said you've already done). It's easy to see if it's not identical in either in avisynth or other programs with amplified difference masks - this makes even the most miniscule changes are dramatically visible

There can be other causes for differences in md5 check or similar checksum tests. e.g. metadata tags, header differences, container differences - but the decoded image (uncompressed) should be bit for bit identical . There can be other uncompressed YCbCr 4:2:2 configurations as well : UYVY, YUY2 . The decoded image will be identical, but checksum tests will be different because of the arrangement and how the data is stored

[jagabo]

There is now a 99% match between the files. This may as well be because cdcheck also checks the creation/modification date

You can use the command line FC with the /B switch. It will perform a binary compare of the data in the files.

 FC /B file1.avi file2.avi

Of course there are many other file comparisons tools but that one comes with all versions of Windows.

Beware that different programs may pad the AVI differently or arrange the chunks differently. So you may not be able to use files created by different programs.

A way to compare raw YUY2 data from different program is to use GraphEdit and the DUMP filter to dump raw YUY2 frames to a binary file:



Of course you can also remux with VirtualDub in Direct Stream Copy mode.