Encodeing times are varying?

[bodomjuho]

I have two films (.avi) which both are 1½ hour long.
First takes 15 hour to convert to SVCD
and second takes 30 hour to convert to SVCD.
I'm using TMPGEnc without VirtualDub.
What does incidentally VirtualDub's Frameserving do?

Does anybody know why the second film takes so long time?

Both have MP3 as audio format, but DivX codecs may be different.
Could that be the reason?

[fmctm1sw]

15 hours is an awful long time for an encode. Are you doing any kind of filtering, etc? A frameserver will eliminate an intermediate files created when you do your editing (like removing commercials). I know there are guides on it here somewhere...

[bodomjuho]

I have 1000MHz computer with 128mb memory.
Should it encode faster?

I use 2-pass VBR mode to have smaller file sizes with better quality.
I don't use any filtering just that the Motion Search Presicion is on Highest Quality And Video Arrange Method is on Full Screen Keep Aspect Ratio.
Those are only changes to the default options.
And I always try to fit one SVCD film to 2 CD-R

I have never met any commercials on encoded films. I'm using TMPGEnc Plus

[theDruid]

Different video codecs (DivX) may contribute to the time it takes for the different movies.

To have the Motion Search Precision at the highest quality/slowest setting, and do a 2-pass VBR encode on a 1ghz machine is going to take a long time.

The 'complexity' of the video may have something to do with the difference in timings as well - on a 2-pass encode, TMPGEnc is doing a lot of calculations about how best to allocate bitrate to different parts of the film (higher bitrates allocated to more visually complicated parts of the movies - e.g. rippling water, fire/explosions, high-action scenes, panning shots etc..)

128mb isn't much RAM these days either - what OS are you running? That may be making your machine encode slower than it could do if it's having to resort to the paging file on your disc a lot (tens of thousands of times slower than doing it all in RAM).

The CPU is the main determinant of encoding speed, but so little RAM with a 'modern' OS (2K/XP) will be a big bottleneck for anything you ask your PC to do. See posts elsewhere about monitoring your system with the Task Manager:



If your available memory falls too low, then the lack of RAM is acting as a bottleneck in the system. You can see my system is using more than 128mb of its RAM without doing much - just running Outlook Express and a couple of instances of Internet Explorer. That's with Win2K SP4.

Does that answer some of your questions?

cheers,
mcdruid.

[bodomjuho]

Thanks about hints!

I have Win98.
"That may be making your machine encode slower than it could do if it's having to resort to the paging file on your disc a lot."
I'm not sure that if I understand this correct, but does that mean that my harddrive is doing some job that my RAM should do???
Can I change this with some settings or do I just have to buy more memory?

[Gazorgan]

Windows 98 and 128 MB of RAM isn't going to get the job done. You want 256 minimum. 98 isn't real stable after 24 hours of continous usage. W2K/XP is generally good for at least a week of constant operation.

You ahve to re-boot between encodes, or it may be slow.

I bet 1 is already in the correct resolution, and the other is being resized. What your MPEG encoder is doing behind the scenes can radically affect your encoding times.

Are you 100% sure you used exactly the same settings? What are the AVI's resolutions?

[theDruid]

That's more-or-less exactly what it 'resorting to the paging file' means. When the system runs out of space in the RAM, it has to copy some of the RAM's contents to the hard drive (and the paging file is a space on the hard drive that your OS sets aside for this task) to free up space in the RAM. So, it ends up copying stuff back and forth between the RAM and the paging file, which slows things down a lot.

Another name for this is Virtual Memory (& on Linux it's called the swap file).

Win98 actually uses up a lot less RAM than 2K/XP do anyway, so my comment's not so relevant on that front.

If the RAM is a bottleneck (and a lot of apps such as Office etc.. use a lot of memory over and above what Windows does) you can't do a lot about it as far as I know, other than get more RAM.

There are some programs that claim to make your RAM more efficient and defrag it etc.., but I'm a bit suspicous about them. They have to take up RAM and CPU clock cycles themselves anyway, so I can't see there being a big performance increase.

There was a utility I saw somewhere that allows you to monitor the memory usage in 98 - I'll post back if I remember what it was called.

I don't think you'd do badly to upgrade with a bit more memory anyway - 128mb is not that expensive nowadays, and you'd probably notice a difference in general with 256mb.

cheers,
mcdruid.

[edit]Gazorgan - posted at the same time again! - I've got to start typing quicker (or waffling less!)[/edit]

[bodomjuho]

Noup, neither are in correct resolution.

Here is some info I took with GSpot about the two films:

Took 18 hours to encode, XviD
Aspect: 576 x 304 (1.895 : 1)
FPS: 23.976
Bitrate: 776 kb/s
Duration: 01h 46m 32s
Audio: MP3
Bitrate: 136 kb/s (68/ch x 2 ch) VBR LAME3.92
Fs: 48000 Hz


Took 26 hours to encode, DivX 3 Low-Motion
Aspect: 640 x 272 (2.353 : 1)
FPS: 25
Bitrate: 966 kb/s
Duration: 01h 26m 27s
Audio: MP3
Bitrate: 134 kb/s (67/ch x 2 ch) VBR
Fs: 44100 Hz


"Are you 100% sure you used exactly the same settings?´"
Yes I am, 'cos I choosed SVCD from Project Wizard and did only those above mentioned changes.

Now I tried to use Puertorican CVD template (just that I used 2-Pass VBR) and 28 hours fall to 12 and I can't see any quality loss. And the film fitted into two cd-r.

If I buy more memory I have already two available slots in use. So I have to take another 64mb away and put bigger one to it's place, so I don't get much more memory.