How much speed gain for video encoding moving from sing core to quad?

[keesio]

Hi,
I have been doing a lot of video encode/decode lately. I have an older system (P4 2.8 with HT, 2 GB mem) and it is fairly slow. I am wondering how much speed gains I can expect moving to a top line system (quad-core). I am trying to see if it is worth the cost to upgrade just for video encode/decode. It have been doing a lot MPEG2->Xvid and Xvid->MPEG2. I also do the occasional AVCHD->MPEG2. Is it reasonable to expect speed gains on the order of 4-8x (or more)?

Thanks
Ki

[SLK001]

Are you using multi-core aware encoders?

[redwudz]

Probably about four times faster with H264 encoding, but it depends on other factors in your setup and what type of encoding and progams you are using. Newer motherboards have improved bus speeds, hard drive access times, etc. You could do a CPU comparison at Tom's Hardware: http://www.tomshardware.com/charts/cpu-charts-2007/mainconcept-h-264-encoder,380.html?...%2C1313%2C1315

MPEG encoding may not show as much gain. Multiple cores show more gain with programs that can make use of all the cores, but even without that, there are large improvements in multitasking performance. You should be able to do other operations while encoding, with less loss to encoding speed.

[Soopafresh]

It's worth it. You'll be able to play HD material without stuttering as well. CoreAVC h264 decoder is also multi-core aware, it'll make full res playback of your AVCHD files possible.

[edDV]

Try to find benchmarks on the web for your exact software configuration and pay attention to the hardware used.

[John]

For me it was definatly worth the upgrade, not for divx or xvid, I had an amd dual 5600, and it encoded xvid at the same speed as my amd phenom, the cpu speed just hung around 50% which has 4 cores. but h.264 makes full use of the quad core, which has cut the time down considerably.

[jagabo]

Be sure to get a multithreaded release of Xvid. Look for version 1.2.127.

Toms Hardware has some good benchmarks:

http://www.tomshardware.com/charts/processors/xvid-1-1-2,403.html

They use an old single threaded version of Xvid. Oops! I see Redwudz already linked to Toms.

x.264 is a best case scenario for multicore encoding. Nearly a 4x improvement going from 1 to 4 cores.

Note that just going from the P4 to Core architecture will get you a big speed boost with most encoders.

[stiltman]

Note that just going from the P4 to Core architecture will get you a big speed boost with most encoders.

That's putting mildly

I went from a P4 2.6 without Hyperthreading to a Q6600 (not G0 stepping though)

I think my full recodes with DVD-RB were around 6-7hrs, now it's about 45mins to 1 and half hours

But that also doesn't take into account going to a more current architecture too
Faster RAM, I used to have PC133
Faster HDDs, I used to have 5400 ATAs,

What's funny, I think DVDShrink takes just about the same amount of time on my old box as DVD-RB does on my new box

[jagabo]

Note that just going from the P4 to Core architecture will get you a big speed boost with most encoders.

That's putting mildly :)

I went from a P4 2.6 without Hyperthreading to a Q6600 (not G0 stepping though)

I think my full recodes with DVD-RB were around 6-7hrs, now it's about 45mins to 1 and half hours

I meant on a core-for-core bases. A single 2.8 GHz P4 cores runs about the same speed as a single 2.0 GHz C2 core (application dependent of course). Hyperthreading, if the OP's P4 has it, adds very little to the P4's performance. So even single threaded apps will benefit unless he goes for the bottom of the C2 barrel.

[keesio]

Thanks all! A lot of great replies here. Much appreciated!!

Looks like the consensus is that while the biggest gains will be seen when dealing with H264 and when using multi-core aware codecs, there is still a considerable speed gain across the board for an upgrade to be worth its money...