Which one is faster: AviSynth or DirectShow

[haazheel]

Hello everybody,

I'd like to know which of these 2 methods is faster when encoding a video:

a plain DirectShow program, or VDubMod for example...

Thanks in advance...

[celtic_druid]

Why don't you run some tests yourself?

[Mug Funky]

hmmm... which is faster? a red car or a blue car?

the answer: we've got to know more about them... a red car will usually win unless the blue one has speedholes.

heavy filtering in avisynth will be slow, but heavy filtering is also possible (but more clunky to implement with graphedit, etc) in directshow, in which case it will be slower.

[haazheel]

Originally posted by celtic_druid
Why don't you run some tests yourself?

Because I don't know any programs which can encode a video using directshow...

And the comparison would be without any filters...

[sh0dan]

Originally posted by haazheel
And the comparison would be without any filters...
Bingo! You hit the nail on the head!

Passthrough speed is not very interesting for the enduser. Passthrough in AviSynth takes very little CPU compared to the encoding application.

If you just avoid colorspace conversions in all your setups don't expect the speed difference to be anything significant.

[haazheel]

;)

Well, to be exact, I'm developping a soft which, among other things, permits to encode DV films in DivX...

And i was just wondering which method was the fastest, knowing that I must use a resize filter to lower the resolution...

That's all!

[bond]

Originally posted by haazheel
Because I don't know any programs which can encode a video using directshow...3ivx offers a dshow encoder, xvid too after 1.0final

[sh0dan]

I would personally go for VFW. It is probably also slightly faster, as the DS way has to go through the AVI parser/splitter. VFW interfaces direstly with AviSynth.

[morsa]

I've been making some comparisons and when I open any Mpeg4 material (DivX, Xvid,etc,etc,etc) Directshow (through FfDshow) is far faster than Avisource,may be twice as fast.Don't know if it is machine specific.

[sh0dan]

I assume we are talking frame delivery from AviSynth -> SomeApp, and not decoding of video?

[morsa]

Oh, sorry.
I've tested using VdubMod and compressing with Xvid.