Encoding speed variables (x264)

Qyot27 · Post by **Qyot27** » Sun Sep 16, 2007 8:19 pm

Does anyone know of a particular equation that can give me an estimate of approximate encoding FPS based on hardware setup? For example, on my computer, Profile A may usually result in .86 FPS during the encode, causing a 3½ minute video to take about an hour and a half to encode. Profile B may usually result in .11 FPS, thereby taking about 12 hours for the same video. The resolution is the same.

If I wanted to estimate how fast it would be on my grandparents' computer, for example, is there a way that I could figure it out based squarely on their hardware setup? I know that the amount of action in the video can change speed even on the same computer, but this is simply meant as a rough comparison based on a single given video.

I'm not looking for suggestions on how to speed up encoding, as I'm perfectly happy with my excessively insane settings. I'm looking at this purely from a hardware perspective, as pretty much any computer nowadays would be able to encode faster than mine. I just want an idea of how much faster a different setup is without going out an physically testing it.

Zarxrax · Post by **Zarxrax** » Sun Sep 16, 2007 8:40 pm

No. Not really. Even taking x264 out of the equation, would you be able to tell how fast another computer would be at ANYTHING?

A few weeks ago I finally upgraded my PC. My old processor was a P4 2.26ghz, one of the very first models of pentium 4. My new processor is a Q6600, 4 cores, overclocked to about 2.7ghz. I was expecting to see encoding speed increase by about 6 times. I was absolutely shocked when I saw that I was actually getting speeds 10-11x faster.

NeoQuixotic · Post by **NeoQuixotic** » Sun Sep 16, 2007 10:23 pm

Qyot27 wrote:Does anyone know of a particular equation that can give me an estimate of approximate encoding FPS based on hardware setup? For example, on my computer, Profile A may usually result in .86 FPS during the encode, causing a 3½ minute video to take about an hour and a half to encode. Profile B may usually result in .11 FPS, thereby taking about 12 hours for the same video. The resolution is the same.

Estimating speed would be very difficult with so many variables like hard drive, memory, drivers, etc. And what the hell are you encoding with and on that you get less than 1 fps? High profile HD maybe?

Zarxrax wrote:A few weeks ago I finally upgraded my PC. My old processor was a P4 2.26ghz, one of the very first models of Pentium 4. My new processor is a Q6600, 4 cores, overclocked to about 2.7ghz. I was expecting to see encoding speed increase by about 6 times. I was absolutely shocked when I saw that I was actually getting speeds 10-11x faster.

I like the sound that. I just ordered parts for my new computer, CPU being the Q6600. I'm coming from a P4 2.53ghz so I should be very happy with the result. I plan to overclock at least to 3.0ghz using a Tuniq Tower 120. What heatsink/fan are you using Zarx, just curious.

Qyot27 · Post by **Qyot27** » Sun Sep 16, 2007 11:26 pm

anubisx00 wrote:Estimating speed would be very difficult with so many variables like hard drive, memory, drivers, etc. And what the hell are you encoding with and on that you get less than 1 fps? High profile HD maybe?

No, it's SD - the video I just announced, actually. I just use really insane settings* and my computer is an eMachines T1110 - 1 GHz Celeron w/100 MHz FSB, 256 MB RAM, running XP SP1 (and Ubuntu 7.10, but the display is borked right now when I use that). Like I said, pretty much anything nowadays is faster/more powerful than it is. I've learned to be patient, although some things (like this) get a little too ridiculous.

*Copying from MeGUI's config dialog:
'Profile A' (SD-distro) being:

Code: Select all

 --crf 18.0 --ref 16 --mixed-refs --no-fast-pskip --bframes 16 --b-pyramid --b-rdo --bime --weightb --direct auto --filter 1,1 --subme 7 --trellis 2 --analyse all  --8x8dct --scenecut 100 --threads auto --thread-input --progress --no-psnr --no-ssim --output "" ""

'Profile B' (CQ-10) being:

Code: Select all

 --crf 10 --ref 16 --mixed-refs --no-fast-pskip --bframes 16 --b-pyramid --b-rdo --bime --weightb --direct auto --nf --subme 7 --trellis 2 --analyse all  --8x8dct --scenecut 100 --me esa --merange 32 --threads auto --thread-input --progress --no-psnr --no-ssim --output "" ""

Qyot27 · Post by **Qyot27** » Mon Sep 17, 2007 2:10 am

Qyot27 wrote:Ubuntu 7.10

I can't believe I was that oblivious - it's 7.04, not 7.10. I really wish this section allowed user edits.

Zarxrax · Post by **Zarxrax** » Mon Sep 17, 2007 5:32 am

anubisx00 wrote:What heatsink/fan are you using Zarx, just curious.

Just the standard one that came with the cpu. It's probably not a good idea though