View Full Version : Dog-Slow H.264 encoding?

3rd July 2005, 15:33
I'm currently looking to back-up my DVDs onto a new media server, and I had my heart set on using H.264 to retain as much quality as possible but at reasonable file sizes.

My first test encode via Nero Digital was encouraging - up against a similarly sized AutoGK XviD encode, there seemed to be far more in the way of fine detail - the XviD encode was fairly 'fuzzy' in comparison.

The only problem is that while one 50 minute episode of Jonathan Creek took about two hours to encode using AutoGK on a two-pass encode, a single-pass Nero Recode encode took well over four hours! Using x264 via Virtual Dub, average fps was 3-4 :(

I'm using a Dell Dimension 8400 PC with 2GB RAM and a 3.4GHz HT CPU. Is H.264 coding really that CPU intensive or am I doing something hideously wrong?

3rd July 2005, 15:48
well, first of all one pass encoding with recode is usually slower than two passes... however if you want some fps boost just post your settings :)
for what concerns x264, try to use the CLI version with MeGUI... and btw, post your settings.
In both encoders there are options that can be lowered or disabled keeping "virtually" the same quality and giving a nice performance boost...

3rd July 2005, 16:08
I was using the default profile on Nero Recode, just with one-pass encode instead of the default two-pass.

With x264 (via VDubMod) I was trying a single-pass encode at around 2000kbps, 8x8 DCT enabled and everything else at default.

In both cases, I was encoding straight from a VOB file ripped with DVD Decrypter.

3rd July 2005, 17:54
3-4 fps with x264 is indeed slow for your cpu. i get that with my old pentium3 866mhz. but i use the commandline encoder which outputs directly to .mp4...

3rd July 2005, 19:29
You might want to check on your cooling...Your P4 may be throttling if the cooling isn't sufficient, and P4's that throttle under load will slow things down considerably.

3rd July 2005, 19:31
well.. if he's encoding xvid for 2 hours that means the CPU runs stable. It would be a good idea to use MeGUI and post the log here.. MeGUI supports both XviD and x264, so with the same framework external influences can be ruled out.

3rd July 2005, 21:32
Thanks for the heads up - I'll give MeGUI a go.

Any one that's seen the rather extreme cooling solution inside a Dell 8400 will know it's not an overheating problem. I've been encoding XviD now nonstop for over 24 hours with no problems.