Which x264 de-interlacer? which number of passes setting? how many threads?

[hajj_3]

Hi, im new to x264 encoding, i've selected lanzos4 sharpener, im using the HQ-Slower profile.


Which pass setting marked in red should i choose?



How many threads should i choose, i have a dual core (core2duo) cpu.


Which de-interlacer should i use, i used to use kernel deinterlace for my xvid encodes, which 1 should i use for x264.


Im encoding PAL 25fps interlaced PDTV btw.

http://i28.tinypic.com/b509xe.jpg

http://i26.tinypic.com/aw43dw.jpg

thanks guys!

[lexor]

Put threads to 0=auto, I don't see any reason not to use Auto 2 pass (unless you want to save some time at expense of possibly missing the desired filesize, then use Constant Quality), and as for de-interlace I put faith in Analyse button.

[hajj_3]

I just tried that, it selected all the options above and chose "Yadif" instead of the "LeakKernelDeint" that i was using, i'll let you know how it looks once its finished encoding. my settings only get 30fps with a core2 @ 3.6ghz.

[lexor]

heh, one of my crf18 encodes just finished at average of 2.2fps... don't complain.

[Sagekilla]

Pfft, 30 fps is very good; you must be using fairly fast settings, aside from the fact that you have a fast dual core in the first place.

If you think 2.2 fps is slow.. Try dealing with 0.8 fps encodes, and that's not even on HD resolutions. (fyi it's preprocessing that brings my encodes from about 6 fps to 0.8 fps)

[lexor]

If you think 2.2 fps is slow.. Try dealing with 0.8 fps encodes, and that's not even on HD resolutions. (fyi it's preprocessing that brings my encodes from about 6 fps to 0.8 fps)

Yeah I should've noted that those were 2.2fps with zero processing, throw in denoise/resize and I might as well go read War and Peace followed by the Gutenberg Bible.

[hajj_3]

Pfft, 30 fps is very good; you must be using fairly fast settings, aside from the fact that you have a fast dual core in the first place.

If you think 2.2 fps is slow.. Try dealing with 0.8 fps encodes, and that's not even on HD resolutions. (fyi it's preprocessing that brings my encodes from about 6 fps to 0.8 fps)

settings are in the screenshot, 5 bframes, multi-hex, 6 subme, 5 ref frames and other good stuff:)

with 3 bframes, 5 instead of 6 subme, 3 ref and hexagonal i get 54fps. this is with HQ-Slow.

54fps is decent but i'd rather have better qual so will have to settle for 30fps till i get a quad core 45nm and overclock that.

how much faster is quad core than dual core for x264 encoding with the same clock speed e.g 2.4ghz core2duo, 2.4ghz core2quad?

[nm]

how much faster is quad core than dual core for x264 encoding with the same clock speed e.g 2.4ghz core2duo, 2.4ghz core2quad?Over 90% faster, unless AviSynth filtering becomes a bottleneck. x264's threading model scales very well.

[Sagekilla]

Here's a few suggestions to improve your settings:

crf 18-22 (aka constant quality, lower is more transparent to source)
16 B-frames (Might speed things up a bit, increases quality and lowers bitrate generally speaking)
4 reference frames (Speeds things up, minimal hit to bitrate)
Direct spatial (Auto is a bit slower and not that all too useful, imo)
Make sure dct decimate is checked (If it says "no dct decimate" make sure that is NOT checked!)


Minus cq mode, that should speed things up a little and improve quality somewhat. If you take into account crf, it tends to be faster than 2-pass.

[hajj_3]

Over 90% faster, unless AviSynth filtering becomes a bottleneck. x264's threading model scales very well.

WOW, that really is impressive! i was expecting maybe 30-40%. The 45nm quads are 10% faster clock for clock partly due to process shrink, partly due to more cache, so when i get 1 and overclock to 3.6ghz or so it will be like a 4ghz current quad core. Yum Yum!

Here's a few suggestions to improve your settings:

crf 18-22 (aka constant quality, lower is more transparent to source)
16 B-frames (Might speed things up a bit, increases quality and lowers bitrate generally speaking)
4 reference frames (Speeds things up, minimal hit to bitrate)
Direct spatial (Auto is a bit slower and not that all too useful, imo)
Make sure dct decimate is checked (If it says "no dct decimate" make sure that is NOT checked!)


Minus cq mode, that should speed things up a little and improve quality somewhat. If you take into account crf, it tends to be faster than 2-pass.

16 B-Frames is better quality AND faster?? what do you mean by lowering bitrate, thought u said it improves qual?

Im not really sure what the constant quality mode is really, its better than 2-pass auto?

hope you can lmk, little confused, only started learning x264 encoding a few days ago.

[J_Darnley]

If you use more B-frames then you get more quality/bitrate at no loss of encoding speed. It lowers the bitrate for const. qual. and raises the quality for target bitrate. The largest improvement I have seen is on cartoons, I went from 3 to 16 and dropped the bitrate by roughly 10% (IIRC) with no speed loss.

Constant Quality mode isn't any better than 2-pass. It will give a certain quality of the encoded video. 2-pass will give a target file size. The definite upside is that you only have to run one pass so you could save up to 50% of your time. The slight downside is that you have no idea what the final size of your video will be.

[Dark Shikari]

If you use more B-frames then you get more quality/bitrate at no loss of encoding speed.More correctly, x264 allows the use of up to 16, and using "16 B-frames" means it can choose any number it wants, up to 16.

[Blue_MiSfit]

As far as deinterlacer, there is no one fits all. However, YADIF is a great general purpose deinterlacer, probably better than LeakKernelDeint. It all depends on your source.

~MiSfit

[Sagekilla]

Reason for increased speed when you allow x264 to use up to 16 B-frames is because B's are faster to encode than P's. Speed increase is usually slight, and to an even slighter extent I believe encoding speed increases from less bitrate used. (More bitrate = slower encoder in general.)

[odditory]

Yeah I should've noted that those were 2.2fps with zero processing, throw in denoise/resize and I might as well go read War and Peace followed by the Gutenberg Bible.

I didn't know Steve Gutenberg wrote a bible?

[Sagekilla]

Wrong gutenberg.. Now back on topic, if you don't mind sacrificing encoding speed I'd bump up the settings, considering how insanely fast you encode right now. You'd get a nice quality boost in 2-pass, or bitrate reduction in crf.

[hajj_3]

i changed to 16 b-frames, my fps went from 30fps to 25fps, so 16% ish slower. Thought it was supposed to be faster?

[Dark Shikari]

i changed to 16 b-frames, my fps went from 30fps to 25fps, so 16% ish slower. Thought it was supposed to be faster?That seems unlikely; are you sure you didn't change anything else? The B-frame lookahead is extremely fast.