Okay, if I'm not using B-frames, is there anything wrong with AVC in AVI?

[Blue_MiSfit]

The title says it all. I'm capturing to AVI, because that's the only way I've figured out to capture from HD-SDI to x264 (using Digital Rapids and its VFW encoding engine).

I'm using no b-frames (and short GOPs), and 2ch PCM audio.

I know VFW is dicey with b-frames and VBR audio. What else do I need to worry about? The AVI files I generate seem to play fine everywhere.

Thoughts?

Derek

[Biggiesized]

Can you capture the video byte stream and the audio content separately (i.e. _.264 and _.wav)?

[roozhou]

And no mbtree.

[Dark Shikari]

And no mbtree.Why, because that's the option your dice happened to land on today?

[Blue_MiSfit]

@Biggiesized:

Yes actually I can. I simply add additional transcode targets in Digital Rapids. I was thinking of this earlier - I'll probably just capture a 2ch AC3 at 192kbps.

@roozhou / DS:

no-mbtree is part of zerolatency, so yeah actually :)

Derek

[sneaker_ger]

And capturing needs zero latency? :confused:

I'd probably just enable all the options in the VFW I'd also use in the cli (including b-frames). You can always mux to a "proper" container later on. (e.g. using mkvmerge) Or am I missing something?

[Warperus]

Color matrix might be a problem as well as aspect ratio.

[sneaker_ger]

Why? All of them are part of the bitstream, aren't they?

[Warperus]

AFAIK x264 default color matrix is Rec.709. If x264 is being fed by Rec.601 material you end up with color matrix issue. It's easily corrected in x264 cli with avisynth script, but I donno how it is x264vfw. Point is checking won't hurt.
Aspect ratio is being "lost" so often that I don't even know when it works correctly in avi with arbitrary media player.

[J_Darnley]

No, the default colormatrix setting is undefined.

[Blue_MiSfit]

@sneaker_ger:

When you're capturing 1080p24 or 1080k60 and have no control over the capture buffer size, yes you need as little latency as possible :)

~MiSfit