x264 settings "look like source"

[lennox]

Hi! I saw some rips VC1->x264 at bitrates of ~12000 kbps that look like source, I mean it's transparent rip. But I cant' get such good results using different "slowest" settings. Can you give me some advice?

[simonhorlick]

x264 --preset veryslow --crf 18 -o output.mkv input.avs

[lennox]

simonhorlick, thank you. But I want to know what settings affect on this.

[Blue_MiSfit]

It all depends on the source.

CRF 18 is usually transparent, but as low as CRF 16 is sometimes necessary for full transparency with difficult sources.

You should use the slowest preset you can tolerate.

Derek

[lennox]

ok, and how to get source grain on the same place. I want to look may encode and source identically ( encoding bitrate < source bitrate). Maybe some PSY or other settings to change.

[AMED]

x264 --preset veryslow --crf 18 --tune grain -o output.mkv input.avs

Preset veryslow:
--b-adapt 2 --bframes 8 --direct auto
--me umh --merange 24 --partitions all
--ref 16 --subme 10 --trellis 2
--rc-lookahead 60

Tune grain (psy tuning):
--aq-strength 0.5 --no-dct-decimate
--deadzone-inter 6 --deadzone-intra 6
--deblock -2:-2 --ipratio 1.1
--pbratio 1.1 --psy-rd <unset>:0.25
--qcomp 0.8

If you want to be identical, then don't re encode it, keep the source.

[simonhorlick]

ok, and how to get source grain on the same place. I want to look may encode and source identically ( encoding bitrate < source bitrate). Maybe some PSY or other settings to change.

I don't understand, if you want it to look _identical_ then turn off all psy optimisations. This is unlikely to give you better compression than source though.

[mandarinka]

Not at all, without psy settings, retaining detail is much more diifcult, because it likes to blur/throw stuff away.

Also, for "looks like source", crf 18 will be way too compressed, most of the time. 15-16 would be more like it imho, less with mbtree (from my experience encoding anime - clean recent ones / older shaky or grainy ones).

Use interleave() function in avisynth to compare your encode to the source (switch back-forth in virtualdub, the difference between the original and compressed frame will become nicely obvious).

[IanD]

Are there settings that are useful for transcoding x264->x264 with minimum loss?

I have some 1080p material that chokes my media players and all dxva software players except ffdshow (possibly too many ref frames at 14?), so I would like to transcode to a more compatible setting whilst minimising loss. It seems to play fine for a second or so and then pixelates terribly, then plays fine, then pixelates ...

It would be great if there was a way to simply re-encode a small percentage of frames that have issues whilst retaining the original frames that work: sort of like what VideoReDo does with mpeg2 when you want to edit on a B or P frame.

[sneaker_ger]

I'd give up on that idea. Do a reencode at level 4.1 and your preferred settings.

[IanD]

I'd give up on that idea. Do a reencode at level 4.1 and your preferred settings.
It's those "preferred settings" that I'm after, to ensure minimal loss on a 1080p x264->1080p x264 transcode.

The previous responses to this thread haven't agreed on settings that will provide a "transparent" result to a source.

[sneaker_ger]

They are the same as for every other source: slower presets and more bitrate = better quality. Most people around here find crf 16-18 and lower at preset "medium" or slower transparent. There's no mutual agreement on a specific commandline or crf.

[audyovydeo]

They are the same as for every other source: slower presets and more bitrate = better quality.

not exactly. Slower presets = higher compression.

People, don't ever forget this post by akupenguin, things don't get explained as well as this :

http://forum.doom9.org/showthread.php?p=1020500#post1020500

extracts :

"The encoder optimizes between 3 parameters: quality, bitrate, and speed.
There are some complex interactions between options, but lets ignore them for now. To a first approximation, if you use CRF or CQP mode then the only option that affects quality is --crf or --qp, and all other options tradeoff speed vs bitrate (note: this does not mean that you can measure just the bitrate to determine the effectiveness of some option. I said approximation.). If you use ABR, CBR, or 2pass mode, then the only option that affects bitrate is --bitrate, and all other options tradeoff quality vs speed. I can merge those two statements to become: Ratecontrol options trade quality vs bitrate, and all other options trade speed vs bitrate.
"



cheers
audyovydeo

[sneaker_ger]

Slower preset = higher quality, at the same bitrate of course.

[mandarinka]

Also note that at faster speed settings, psyrdo has less effect. So you might not be able to offset the quality drop with higher bitrate easily...