Don't use al CPU power

[bvalter1964]

Problem Description

Hi I noticed that encoding video the rev 7 is slower than rev.6 that is slower than 5.

I have a 12600k CPU and WIN 11, I transcode a lot of file to MKV H264 size 720x400/300 at very low rate (512Kb two passes) and I noticed that CPU load is no more than 65%. Im addition to that i tested few files with different version and noticed about 15% difference time within rev 5 and 7. The output file are almost all identical. Mediacoder with the same files use almost 95% of CPU with better result in terms of time. I tried to change the priority in Vidcoder but there is no change in this beahviour.

I am not sure if this is a bug and/or I posted in the wrong section. In case of , sorry for that

What version of VidCoder are you running?

latest

Encode Log

No response

[RandomEngy]

A few thoughts:

1. Sometimes a video filter (like resize) can bottleneck the CPU. A good test would be to disable all filters and resizing and see what happens.
2. You'll get your encodes done much faster but with the same quality if you use quality targeting instead of two-pass.
3. Something to double check would be Global Options -> Process -> CPU throttling / Allowed Cores, make sure this is at the default 100%.
4. You can encode two videos at once to fill up your CPU cycles: Global Options -> Process -> Maximum Simultaneous Encoding Jobs.

[bvalter1964]

Good afternoon I checked the option CPU cores and it is allowing all of them I tried the quality targetting instead of double pass, it is faster (50% approx) and after few tentatives, I found that a quality factor of 20/19 was providing video file almost all the time with the targeted video rate (around 500 Kb/s) but few times Vidcoder is providing value totally different (up to 800Kb/s) forcing me to recode those file with double pass. Is that normal? Thanks for your time

[RandomEngy]

Sometimes videos have a lot of detail or motion which requires them to use more data to meet the quality target. If you force a lower bitrate for these more complex videos it will look worse. If you are in fact OK with that worse quality you can change your quality target and save a bunch of space on all the other videos. There's no rule that says every video that you encode has to be the same bitrate. What matters is the picture quality.

[bvalter1964]

Hi Thanks for your help, I returned to double pass encoding, but encoding two files at time save around 30% of the time. Thanks again Valter