x264 Lossless question

Hi, good day. I was wondering if is safe to use x264 lossless, and is comparable to Lagarith. I mean, if I reencode this x264 lossless to x264 lossy, it's the same as to reencode a Lagarith to a x264 lossy? And, should I be using CoreAVC or libavcodec to decode this lossless through DSS2()? These question had been retaining my sleep these days, so I would be very gratefull if they could be answered :) Thanks.

x264 lossless has pretty much strictly superior compression to Lagarith, even in intra-only mode IIRC. Unlike Lagarith, it only supports the YV12 colorspace. To decode it correctly, you need a libavcodec from within the past ~2-3 weeks (as that's when support was added) or CoreAVC 1.8.5.

How to encode to lossless?

Atak_Snajpera, huh? --qp 0 is that what you mean? stpdrgstr, lossless is lossless, the input to "x264 lossy" in both cases should be the same.

Thank you very much. Now I can keep encoding at ease :)

Note that for frame-accurate access to H.264 streams (lossless or not) you should use DGAVCIndex/AVCSource() instead of DirectShow. I'm not sure whether AVCSource() already has an updated libavcodec with support for x264 lossless mode though...

i thought the h.264 spec declared that predictive lossless profile was to only consist of IDR frames? Edit: nope, confirmed against the spec... it does allow I,P,B. what's the point of allowing B frames in the first place if it reduces the compression?

I created streams with x264's mode "predictive lossless" mode using P-Frames and even B-Frames (didn't know b-frames are bad for lossless) and CoreAVC as well as recent ffdshow do handle it properly.

so what's a sensible command line for lossless?

no --subme 9 for Slowest ? typo or is there actually something to it ?