Slow video encoding

[Bergschreck]

I installed LMDE/Xfce UP4 in parallel to Ubuntu Natty on my Toshiba Satellite Pro U200. I tried to encode a video with Avidemux to MPEG4 AVC.

The encoding speed is extremely slow, it encodes only 3 frames per second on this hardware. The same video with the same encoder settings makes 9 frames/sec with Avidemux on Ubuntu Natty. That's 3 times faster!

What's wrong here? Are some libraries compiled with wrong compiler settings? (maybe debug instead of optimize?)

[Bergschreck]

Now I installed Xubuntu Precise Pangolin in a third partition of the same machine and did a encode with avidemux (same video, same settings). The result is very astonishing:

LMDE/Xfce: 3 frames/sec
Ubuntu Natty: 9 frames/sec
Xubuntu Precise: 15 frames/sec

I think the difference is how the packages are compiled. Debian packages are compiled for i486, Ubuntu packages are compiled for i686.

IMHO this way LMDE has no future.

I will keep Xubuntu Precise and remove the other 2 partitions.

[mank_in]

If you have multicore processor and use 32-bit LMDE, you must install 686-PAE kernel , see : http://www.linuxmint.com/rel_debian.php

[Bergschreck]

Thanks for that hint. With 686-pae kernel I get 8 frames/sec. That's about the speed of Ubuntu Natty. I'm wondering how Ubuntu Precise can be so much faster. Maybe because libavcodec is also compiled for 486?

[mank_in]

I don't use LMDE and Avidemux. Maybe you can activate multi threading in avidemux preferences : http://www.avidemux.org/admWiki/doku.ph ... ithreading

[Bergschreck]

Avidemux settings were identical on all systems. Threading was set to auto-detect. But even if I set it manually to 2 threads (I have dual core cpu), that makes no difference. LMDE is considerably slower than Ubuntu Precise.