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View Full Version : interlaced x264 r1900, ffms2 - chroma field order swappage (encoder? decoder? both?)


Mug Funky
23rd February 2011, 03:42
hi!

i'm experimenting with x264 r1900 as an intermediate format for uncompressed captures.

one thing i've noticed is when i encode interlaced (both tff and bff), and decoding the result with ffms2 in avisynth is that the chroma appears to be in opposite field-order with respect to the luma (which is perfect :))

i'm currently having trouble seeing if it's a decoder thing, an encoder thing, or something else.

the input going into x264 (with demuxer set to lavf to avoid the indexing pass) is v210 - that is uncompressed 10-bit 4:2:2.

i've tried both NTSC and PAL captures

considering there's decoding and encoding happening all through the chain, and the source is 4:2:2, i'm at a loss to know where the problem is occurring.

any thoughts?

[edit]

it seems that ffms2 in avisynth is the culprit here. ffdshow (using ffmpeg-mt to decode) worked fine.

[edit]

nope, there's definitely a problem.

tried 2 avisynth scripts, both identical except one delivered yuy2 and the other had a converttoyv12(interlaced=true) at the end.

decoding the result and slapping utoy() on it showed the yv12 one had chroma interlacing, the yuy2 one seems to have progressively downsampled to yv12 before encoding.

am i missing some thing in telling x264 what i'm giving it? i thought maybe the --tff or --bff switches would be sufficient, but i suppose that may not necessarily be.