Slow encoding

[DaRtHmAuL]

Hi everybody,
i'm testing to encode big HDTV *.TS files into smaller files to burn those on DVD-5. Well, i tried convert *.TS to xvid 1280x720 but it's extremely slow on my machine (Athlon64 3200+ @ 2200Mhz + 2GB of ram). I get 7-9fps on the first pass and 5-6 for the second. I tried x264 + MeGui too and it was worse : 4-6fps on the first pass and only 1-2 for the second...
Is it normal ?

here are my two *.avs scripts :

For XviD :
Loadplugin("C:\Tools\Video\AviSynth\plugins\dgdecode.dll")
Loadplugin("C:\Tools\Video\AviSynth\plugins\decomb521.dll")
Loadplugin("C:\Tools\Video\AviSynth\plugins\simpleresize.dll")
Loadplugin("C:\Tools\Video\AviSynth\plugins\undot.dll")
mpeg2source("H:\HDTV\The Matrix - [XviD-720p]\the_matrix(xvid).d2v")
Telecide(order=1,guide=1,post=2,vthresh=30)
Decimate()
UnDot()
simpleresize(1280,720)

For x264 :
Loadplugin("C:\Tools\Video\AviSynth\plugins\dgdecode.dll")
Loadplugin("C:\Tools\Video\AviSynth\plugins\TIVTC.dll")
mpeg2source("H:\HDTV\The Matrix - [XviD-720p]\the_matrix(x264).d2v")
tfm().tdecimate()
Lanczos4Resize(1280,720,0,0,1920,1080)

Thanks for your help.
Cya

[Suchy]

Firstly check encoding in raw XviD. Reencode a small part of this by using any losless codec (for ex. FastCodec), without using, any filters. If it's slow then probably is something wrong with DGDecode.dll (aka MPEG2 Source).

Next, encode in XViD this reencoded file. If it's slow then it means that is something wrong with XviD settings or compilation.

Later reencode this, using telecide and decimate. If slow then you now what is wrong. If not, then use next filters. Do this way until the end.

P.S.
There is always possibility, that AviSynth slow down reencoding.

[DaRtHmAuL]

I've already tried to reencode small part of my HDTV content without any filters but it was barely the same. The gain is small.
For comparison : I backup my DVDs with CCE and got 2.5/3 speed which is good i think.

[DaRtHmAuL]

Well, i tried to encode the same little sample to XviD 1000kbps/640*360 instead of 4500kbps/1280*720.
I got 30-35 fps. When i reencode without any filter at 1920*1080, it is slow too. It seems the resolution and bitrate are very important part of the encoding time. is it normal or strange ?

[foxyshadis]

Entirely normal. The more resolution, the more blocks to motion search. And the more bitrate, the less the encoder will decide to skip blocks before searching.

[akupenguin]

Why do you use different ivtc filters for the two encodes? Surely whichever produces better matches is better for both.

[DaRtHmAuL]

Hi,
no i definitely use the x264 *.avs for XviD encoding with MeGUI.
it works very well but not fast enough. I'm backing up a movie at 4450kpbs, 1280*720 with XviD VHQ, QPel and Mode 6 functions enabled. Got 7-8fps on the first pass and 3-4 (got 5-6 without QPel) for the second... To backing up a film of 2 hours long, it takes "only" 22 hours... i don't prefer to test x264 codec supposed to be slower than XviD.

[Koepi]

At that resolution you may try disabling qpel. That should give you a significant speed boost. Also set vhq to 1, that's the best trade-off between bitrate-gain and speed.

Cheers
Koepi

[DaRtHmAuL]

Yes Koepi,
i tried to disable QPel and i reached 5-6fps but this function is very interesting. I made some tests and the difference with QPel activated is noticeable. For me, the gradient are managed better but the encode remains slow with it. It's true. Is it necessary to activate VHQ for BFrames ?
Thks

[Your_Idol]

its normal to get less then 10 fps with motion search at 6 and VHQ at 4 with hd

[Blue_MiSfit]

Dude. Totally. Encoding HD is really freaking slow :)

I would be happy with over 3 fps or so with x264 encoding 1080p from a mean script :)

No real way around it. Big resolutions equal big ammounts of computations which equal big ammounts of time :)

Too many :)'s...

~MiSfit