Avisynth Help thread

[pichu]

I don't think I should answer that question, and I'm pretty sure the answer would have been clear when you visit the link. I don't judge other people's work... But do tell me, what's wrong with MY script?

The reason I made those scripts is that I do not want to type out so much avisynth codes when overlaying my signs, and that I want a way to overlay a lot of signs in one overlay by having them spliced continuously in one video (which is why I deal with global variables--since avisynth doesn't support object-oriented scripting)... This is really only for me, but then I've decided to share it with fellow typesetters.

The script will cause memory faults in AVISynth 2.55 and under, which is why I suggest to use 2.56 and above. heh It also might take long to parse due to the conditions, but once it's finished parsing, everything will run normally.

PS:

His -
title = imagesource( "C:\Documents and Settings\Greg\My Documents\VirtualDub\grev-logo\beyblade-logo%04d.png", start = 0001, end = 0123, use_devil=true, pixel_type="rgb32").assumefps(last)
insertsign(last, title, 153, 276)

Mine -
imgsign("C:\Documents and Settings\Greg\My Documents\VirtualDub\grev-logo\beyblade-logo%04d.png").sign(153,276)

---

Sorry, another shameless promotion of my work

[martino]

I can see most (or least the most obvious ones) differences myself, it was mostly aimed to help others who may not know from looking at the code/etc... but fine. Either way, you've given a simple explanation which should suffice to most I guess.

Originally Posted by pichus

But do tell me, what's wrong with MY script?

Nothing by just looking at it, apart from the fact that it looks somewhat complicated -- mainly when compared to the other one. Comes down to personal preference (laziness? ) which one you want to use I suppose.

P.S. You don't need the .assumefps(last) for overlaying IIRC

[dragon5152]

Originally Posted by martino

P.S. You don't need the .assumefps(last) for overlaying IIRC

If the overlay is 23.976 and the source is 29.97 which occurs on VFR sources a lot, it might be needed

[TheFluff]

Wrong, overlay() doesn't care about timestamps and hence not about framerates, it just pairs up frames from the input clip with frames from the overlay.

Also jesus christ pichus that is a hilariously overcomplicated way to overlay signs.

[pichu]

Originally Posted by TheFluff

Also jesus christ pichus that is a hilariously overcomplicated way to overlay signs.

Define: "Complicated"

It can be as simple as:

avisource( "op.avi" )
avisign( "afx_karaoke.avi" ).sign
avisign( "credits.avi" ).sign( 100 )
imgsign( "logo.png" ).sign( 500 , 700 )

then an afx karaoke with credits and logo starting later is overlayed correctly on top of an opening sequence. How much simpler you can get?

[fireshark]

I think he means your code

[pichu]

Well, instead of being so egotistical over this, why not spend the time to put my link on the first post in the FAQ?

http://pichu.org/overlays

And, I am opened to suggestions anyways. And, trust me... This is one of the simplest scripts I wrote.

[dj_tjerk]

function insertsign(clip mainclip, string filename, int startframe, int "endframe") {
	overlayclip = avisource(filename)
	endframe = default(endframe,startframe+overlayclip.framecount-1)

	begin	= (startframe == 1) ? mainclip.trim(0,-1) : mainclip.trim(0,startframe-1)
	middle	= mainclip.trim(startframe,endframe)
	end	= mainclip.trim(endframe+1,0) 
	
	middleoverlay = Overlay(middle, overlayclip, mask=overlayclip.showalpha())
	
	begin = (startframe == 0) ? BlankClip(mainclip, length=0) : begin
	end = (endframe == mainclip.framecount-1) ? BlankClip(mainclip, length=0) : end 
	
	return begin ++ middleoverlay ++ end
}

Usage: insertsign("blabla.avi", 400)

One extra line and fluff's script basically does the same. Making one big clip of signs hasnt proven useful for me, as I often need to upload v2's of specific signs (not that matters much.. it's more work for the encoder to remove and add some lines though with one big clip).. and I don't like working in one big composition. I also never use still images, i always make clips in AE, even if the scene is static.. Also, I don't like dragging and dropping, I prefer some weird .jar that i double click on and it generates the .avs script, and maybe even 7z's all the files.

In the end.. who cares.. pichu's script works, fluff's script works, and if I may believe avisynth's mediawiki:

Input for overlay is any colorspace, and colorspaces of different clip doesn't matter! The input clips are internally converted to a general YUV (with no chroma subsampling) format, so it is possible for the filter to output another colorspace than the input. It is also possible to input video in different colorspaces, as they will be converted seamlessly. It is however not recommended to use overlay only for colorspace conversions, as it is both slower and with slightly worse quality.

the colorspace of your overlay clip doesnt even matter..

[pichu]

colorspace only matters when you have to deal with video splices... But, thanks for reminding me this... I just removed colorspace and automatically set colorspaces for the video clips splices over here.

(and the only part I haven't bother checking is the audio portion of the video clips splices, so one will have to convert them manually -- but it's an easy task to convert though in my avisign function... I just never encountered problems with it though)

To splice in a video or part of the video clip in replacement of the video portion -- very much like overlay without the Alpha channel - only faster.

avisign( "sign.avi" ).sign( 100 , mode="splice" )

Sometimes you need to use splices because how AFX transfer blending modes work differently from AVISynth, so overlay will not always work.

Also, you can use v1b codec if you want to with a separate RGB and Alpha channel, defined... or jpg with a separate grayscale mask file.

[dj_tjerk]

In the days when i didnt have much space, i even encoded a separate xvid alpha video lol xD (and the rgb also in xvid). Anyway, I don't see what splices have to do with blending modes in avisynth? I thought it was just your way of making one big clip.

[pichu]

Originally Posted by dj_tjerk

In the days when i didnt have much space, i even encoded a separate xvid alpha video lol xD (and the rgb also in xvid). Anyway, I don't see what splices have to do with blending modes in avisynth? I thought it was just your way of making one big clip.

no it doesn't... but i just set that as a condition... I can even put an option like "Add" so that it adds to the clip (addclip, addbefore, addafter)... but i don't think it's needed for any of the work i did. If i want to do this, I'd just trim/avisource manually.

[comatose]

I think what pichu means is that sometimes AFX doesn't create clips that Avisynth can properly overlay with transparency, so a complete AFX render is required.

Then, you have to use splice. e.g. trim(before)+afx+trim(after)

[mad_cracker]

Hi minna. I was wondering if there is a way to overlay videos without re-encoding. I mean, like a video layer that we can switch off and on whenever we want. Just like DVD subs.
Thanks

[jfs]

Nope, there isn't.
Actually I think DirectShow (using Video Media Renderer 9, possibly also 7) allows to build graphs that can do something like that, but there isn't any user friendly way to achieve it.

[Dark Shikari]

Originally Posted by mad_cracker

Hi minna. I was wondering if there is a way to overlay videos without re-encoding. I mean, like a video layer that we can switch off and on whenever we want. Just like DVD subs.
Thanks

Avisynth will do the trick.

[mad_cracker]

Can you please suggest some tutorial for that?
Thanks jfs and thanks Dark Shikari.

[martino]

Overlay()...

[jpwong]

Originally Posted by martino

Overlay()...

I don't think that's quite what they want, they're describing something that works like subtitles do in a DVD. That is, from the player, you can say, show the extra video layer on screen, or turn it off at any given time, so say the end user could watch the whole thing with that video layer on, then go back and re-watch it with it off.

If that is what in fact they want, I don't think it's something you can do in avisynth.

[TheFluff]

If you feel like being very annoying, I'm pretty sure it can actually be done (with Avisynth, no less).

The process would be something like this:
1) encode a multi-segment MKV file where the first segment contains what you want to overlay and the second segment contains the actual video to overlay on.
2) mux it with ordered editions so anyone with a proper splitter will only see the second segment.
3) tick the "Avisynth" box in ffdshow, input code to load the mkv file you're playing with ffmpegsource (will read the first segment) and do the appropriate overlay()'ing on what's currently actually being played.
4) untick the avisynth box to disable overlaying.




(ps: don't actually try this at home, kids)




edit: obviously, if you don't mind distributing multiple files you can of course provide the overlay as a separate file together with an Avisynth script that does the overlaying; you can play that in a video player directly to get the overlayed version, and the ordinary video file to get the non-overlayed version.

[Dark Shikari]

Originally Posted by jpwong

I don't think that's quite what they want, they're describing something that works like subtitles do in a DVD. That is, from the player, you can say, show the extra video layer on screen, or turn it off at any given time, so say the end user could watch the whole thing with that video layer on, then go back and re-watch it with it off.

If that is what in fact they want, I don't think it's something you can do in avisynth.

If they just need it for personal use, its really easy to do with a simple Avisynth script. Comment out the overlay line to disable the overlay.