"Good-Enough" QTGMC/FFMPEG Presets?

[Okiba]

Hi everyone,

So while I'm de-interlacing my (SD) videos into x264, I use pretty "expensive" setup:

- QTGMC Preset is set to slower
- FFMPEG Quality is set to 18, and Preset is set to slow

Which I really like the end product, some videos takes a lot of time to compress. I have couple of friends who requests my help capturing couple of videos. I'm going to hand them the lossless format, but I suspect they are not going to tell the difference if I'll use use less-expensive de-interlacing version (so they can watch it instead of opening the lossless file). So It's subjective of-course, but for the untrained eye. Which settings are you using when creating x264 file? I start to do some benchmarking (like going to Preset Fast on FFMPEG, and set QTGMC preset to Slow), but I figured I'll ask you guys, perhaps you can save me some benchmarking.

Thanks!

[jagabo]

Are you running AviSynth(+) multithreaded? What's your CPU usage when encoding? In any case QTGMC(Preset="fast") is usually adequate. x264 preset veryfast is adequate for casual viewing, previewing.

[Okiba]

I'm running the compression on a dedicated Windows 7 machine (so I can keep working on my main Desktop). It's has rather old CPU (Intel Core 2 Quad Q6600), but I have a script that runs those in batch so I just leave it on compressing on the background.

I am running AviSynth+. QTGM is set to run on Muilthreaded (SetFilterMTMODE("QTGMC", 2)), and I set EdiThread to be 3. Also prefetch is set to 3. I will give QTGMC Fast with very fast x264 preset a go. Thank you!

EDIT: Forgot to mention CPU when encoding is around 80-85%.

[jagabo]

Note you can run any encoding at low priority and it will have hardly any noticeable impact on foreground processing. Use a batch file that starts with:

start /b /low "ffmpeg" ffmpeg.exe (follow with your ffmpeg commands)

[Okiba]

Oh, cool idea. I wasn't thinking about running in on low priority process. Perhaps this will enable me to run it on the stronger machine (and I can just change the priorty during the night when I do not work). Will give it a test. Thanks!

[jagabo]

There's no need to change the priority at night. If no other process is requesting CPU time even a low priority process will get as much as it can use. Priority only has an effect when multiple processes are requesting CPU time -- the higher priority process get more, lower priority processes get less.

[Okiba]

Oh, was sure there's a limit to low PRiorty processes. Great. Thanks!