Decomb39 Speed?

[mmgrover]

I was just wondering if anbody else noticed a speed decrease with
Decomb39?

Using:
Telecide()
Decimate()

I was able to get about a speed of 0.800 - 0.900 in CCE using Decomb38. With Decomb39 the best I get is 0.200 max?

Any Ideas?

mike

[Synth]

Try using "SetMemoryMax(40)" in your avs script (minus quotes).

Higher values than 40 give me increased speed but suck up the system memory rather quickly.

Assumes your using avisynth 2.x series.

[Guest]

The only explanation is the SetMemoryMax(), as Synth said. What version of Avisynth are you using?

Also, please get Decomb 3.91. It has an important fix in Decimate().

[mmgrover]

What would be the recomended amount for SetMemoryMax() with a
machine that has 1.5 gig of ram?


I have a P4 2.2 Gig with 4 Seagate 70 SCSI drives at home.


mg

[Guest]

I'll let dividee handle this query. I am not familiar enough with the internals of Avisynth to answer usefully. I have mine set to 100Meg, however, as I like having a lot of frame cache.

[dividee]

A minimum amount of memory is needed for every script to run at full speed. With more, you gain nothing. Unless you do very complicated scripts, a few dozen MB is usually enough. But with so much memory at hand, set it at 256 MB and forget about it.
In 2.05 and future versions (and in pre-1.0b6), you don't need to use SetMemoryMax (unless you want to use less memory) as it will use much more memory by default.

[mmgrover]

I tried using "SetMemoryMax(100)" with AVISynth 2.05.
Viewing the avs file in MediaPlayer it looks ok, but when
the avs file is encoded with CCE, all I get is a solod black
frames with some red lines at the bottom?

mike

[Guest]

Your first post implied that you were working fine with CCE.

If you remove the SetMemoryMax(), does it work OK (but slow), or has something else changed in the meantime?

Sounds like you are mixing up symptoms here and getting us all confused. :)

[jdobbs]

@mmgrover

I tried Decomb39 briefly and experienced similar (large) speed drops. I stepped back to the previous version. I made the assumption it was because of the Pentium specific enhancements (I'm using an Athlon TBird processor).

What type of processor are you using?

jdobbs

[int 21h]

I, too, have noticed these speed problems, even with SetMemoryMax set to the recommended values. However, I am running a P4. I simply rolled back to 1b5 or whatever the heck I had before and the speed was back to normal. :(

However, I traced my problems back to new Avisynth.

[mmgrover]

I was trying the SetMemoryMax(100) to help speed up Decomb391.
As I had stated, Decomb391 runs considerably slower than
Decomb3.8.

jdobbs, I am using a P4 2.2 gig with 1.5 gig of ram...

Trying different versions of AVISynth had no affect on the speed
of Decomb391.

I did find a filter called IVTC.

Speed results using AVISynth and Decomb -> CCE:

Decomb3.91 0.180 - 0.200
Decomb3.8 0.870 - 0.878
IVTC 1.120 - 1.200

IVTC also worked on a DVD I have called Titanic.

mike

[Guest]

This all makes no sense. There is no Pentium-specific code and I have a Palamino 1900. My tests show no slowdown from Decomb 3.8 to 3.91 and
the only change was addition of mode 2 to Decimate.

Has anyone that claims this slowdown even with SetMemoryMax() tried it with Decimate(mode=0)? Has anyone tried to isolate the "problem" to Telecide() or Decimate()? Does the slowdown occur only when serving into CCE, or when playing the AVS?

[Peters]

No speed decrease for me with the new version.
I'm just using Telecide(), encoding with Virtualdub

Avisynth 2.05, Athlon XP 1.8 ghz

[jdobbs]

@neuron2

As a test, I just ran two identical scripts on the same source. The only thing I changed is from one .DLL to the other (decomb38 and decomb39). Here are the two scripts:

------
LoadPlugin("C:\PROGRAM FILES\DVD-RIP\AVISYNTH\MPEG2DEC.DLL")
LoadPlugin("C:\PROGRAM FILES\DVD-RIP\AVISYNTH\DECOMB38.DLL")
mpeg2source("d:\image2\stng0109.d2v")
trim(0,2000)
Telecide()
Decimate(cycle=5)
BilinearResize(352,480)
ResampleAudio(44100)
------
LoadPlugin("C:\PROGRAM FILES\DVD-RIP\AVISYNTH\MPEG2DEC.DLL")
LoadPlugin("C:\PROGRAM FILES\DVD-RIP\AVISYNTH\DECOMB39.DLL")
mpeg2source("d:\image2\stng0109.d2v")
trim(0,2000)
Telecide()
Decimate(cycle=5)
BilinearResize(352,480)
ResampleAudio(44100)
------

On the first script my speed indicator was .636 on the second it was .241 -- it dropped to less than half its version 38 speed.

I'm running CCE version 2.50 on a 1.3Ghz TBird Processor on an ASUS AV7 motherboard. I have 512MB of memory, and I'm using an ATA100 60GByte hard drive. The source was NTSC (STNG Episode 9 from year 1)

Hope that helps.

jdobbs

[jdobbs]

The problem is definitely related to DECIMATE. If I comment that line out, the speeds are identical. If I comment out TELECIDE and only run DECIMATE the speed comparison is 1.05 to .422

[Guest]

@jdobbs

Thank you for the test results. What version of Avisynth were you running with?

Please do two things for me. PLEASE!

1. Try exactly as before but use Decimate(mode=0).

2. Try comparisons as before but not feeding into CCE, just playing the AVS.

[jdobbs]

@neuron2

AVISynth version shows at 2.0.4.0

1. Tried with decimate(mode=0) -- DECOMB38 for .628 and DECOMB39 got .640 --> pretty close.

2. It's hard to tell anything by using Media Player, so I ran the original scripts through VirtualDub converting to DIVX to take CCE out of the equation. On DECOMB38 I get 11-13fps, on DECOMB39 I get 4-6fps. Pretty much the same results.

jdobbs

[dividee]

@jdobbs:
With Avisynth 2.04 you should DEFINITELY use SetMemoryMax !

[jdobbs]

@dividee

Thanks, that must be it. I just switched to version 2.0.5.0 and the problem went away. I get virtually identical speeds using the scripts I posted above.

@neuron2

That's what I get for not staying current... I appreciate your help.

jdobbs

[WarpEnterprises]

Can confirm the SetMem-cause. Decimate is a quite good test for how much mem is allocated by default ;)

Else there is identical speed no regard which settings.

Btw a good test for speed of a filter is to crop the video right afterwards to e.g. 8x8 and save this in VD as AVI uncompressed:

Decimate(mode=0, cycle=25)
Crop(0,0,8,8)

[Guest]

It appears that there is at least one version of Avisynth that is just defective.

Therefore, I recommend upgrading to Avisynth version 2.05. This way you'll get dividee's wonderful plugin directory support as well as be able to take advantage of the new features coming in Decomb 3.92.

If anyone experiences a slowdown when using 2.05 please post here.

Thank you all for your test results and feedback.

[JuanC]

There's no slowdown with decomb 3.91 on my P4 1.6A @ 2133. fps are the same as in 3.8. And the jerkiness in mode=2 is gone!! I'm using AVIsynth 2.05.

Thanks Donald! :)

[Guest]

Hallelujah! Thanks, JuanC. You've made the dents in the side of my head feel much better.

[OUTPinged_]

No slowdown when switching to 391 from 380 for me, but only in mode=0. A possible cause may be old version of avs.

[metallikop]

I have another issue w/ decomb that I don't think has been mentioned. When using decomb 3.91 and avisynth 2.05 I get an access violation when there's about 2 seconds left in the encode (2pass 1st pass xvid codec). Here's my .avs:

----------------
LoadPlugin("E:\PROGRA~1\GORDIA~1\mpeg2dec.dll")
LoadPlugin("E:\PROGRA~1\GORDIA~1\decomb.dll")
MPEG2source("F:\DVD\somemovie\somemovie.d2v")
Telecide()
Decimate(cycle=5)
----------------

I don't have the error/crash with 3.8.

CPU: AMD Tbird 2200+ XP

[Guest]

Please try without Decimate to isolate it between Telecide and Decimate. If in Decimate, try using Decimate(mode=0). Please let me know the results. Thank you.

[wmansir]

I have also encountered the slowdown in Decimate mode 2, mode 0 works about as fast as the previous version.

I have a problem with 3.91's decimate funciton not detecting the correct duplicate frame on some video. I don't want to start a whole new thread about it, so I will post the info here.

I have been encoding The Sopranos, season 3, and for the last 3 episodes switched from Decomb 3.8 to 3.91. When watching the final output I noticed some duplicate frames in dark, low motion scenes. After messing around with the script I found that Decimate was not detecting the correct duplicate. A quick check showed that 3.8 handled the scenes fine. I could try to provide a sample if you would like.

[Guest]

I'm aware of the issues. Please use 3.91 and mode=0 unless you run into issues with low frame rate anime, when mode=2 will give better results. I never should have made mode=2 the default.

I am integrating the new duplicate detection into Decimate() this weekend. Watch for the new version early next week.

Thank you for your information.