Is blender limited to rendering out 24 Bit AVI files, only RGB color information?
Cool 3D, a lame ulead product, can render out 32 bit AVI files wich retain the alpha channel information. I’ve used it extensively to produce some simple animation AVIs. I can then import the video file into Vegas Video 4.0, and the transparency is maintained.
Can someone in development look into this? It should be fairly simple to implement.
The problem is, it’s a hassle to deal with all those pictures, and most NLEs hate dealing with a bunch of small clips.
This only works for uncompressed avi anyway, no avi compatible compressioni schemes that I am aware of even support an alpha channel, and I’ve tried many. So, quality wise it is just as good as rendering out targas and reassembling them, only easier to work with for both the user and the NLE software.
Anyway, I suppose it’s more of a sugestion. It Should be relatively easy to implement the changes necessary to make this feature available in blender.
From my ( admittedly poor ) understanding of Hollywood animation, the standard format for a ‘clip’ is a directory full of individual frames. Filmgimp ( now Cinepaint ) has features to deal with just such a thing.
Question: does pressing the RGBA button make any difference when rendering as .avi?
I’ve been using Vegas for awhile now, and it handles image sequences with no problem at all, and is my preferred way to render out of Blender, as I seem to get better quality than AVI RAW. When I want ALPHA I just select RGBA and use the PNG format.
I’ve given a quick look at the Open DML AVI file format documentation, and it never mentions anything about an alpha channel or transparency. Like I said in another thread on the same topic, adding another channel to the color encoding would most likely be sketchy at best and probably result in incompatibility with some programs.
Not trying to be insulting, but this is something that I have done for a couple of years now, and it is a feature that should probably be implemented in Blender. It would simply make things easier. I don’t know what documentation you’ve read, nor do I really care…I know that it can be done, and that it can be done well. This is not the question…The question is, why doesn’t Blender do it?
If you goto the vegas forum you’ll see many posts on the subject. This is a feature of uncompressed avi files that is heavily used, regardless of what a document might suggest.
However, since you are probably not a dev, or a programmer this discussion is probably null at this point, and I’ve posted elsewhere in the form of a suggestion, as I am now thoroughly convinced that this feature has not yet been implemented.
Yet, I still have the notion that it’s more of a bug, because it seems to have been the intended functionality of the current interface to allow alpha channel rendering in an AVI file. It is so widely used that it is difficult to imagine that a program as robust as Blender would not offer it.
From my ( admittedly poor ) understanding of Hollywood animation, the standard format for a ‘clip’ is a directory full of individual frames. Filmgimp ( now Cinepaint ) has features to deal with just such a thing.
Question: does pressing the RGBA button make any difference when rendering as .avi?[/quote]
There is no question that NLEs can import individual frames in the format of BMPs, PNGs, TGAs, etc…I do it myself…
However, from experience the performance of many lower-end (non-hollywood type) systems like Premiere, and Vegas can be degraded unacceptably under these circumstances.
If you’ve never used an AVI file with an alpha channel then there is no refference for your claim that Vegas handles the image sequences ‘with no problem at all’
I’ve tried it both ways, and it ‘seems’ to work better with an uncompressed AVI file, in terms of rendering, image manipulation, timming, etc…
Imagine if you could treat your image sequence as a single videoclip.
What I was trying to say is that I haven’t found any guidelines on adding such a channel. If there’s a non-written standard that I didn’t find, nice, but without further proof that it doesn’t break compatibility with programs compatible with the AVI standard, I think it’s safe to say that this is not something that we would want. <hint>if you have an example of such a file with alpha info with which we can test compatibility, it would help.</hint>
My assumption was based upon the fact that every reply seemed bent on convincing me that this shouldn’t work or that I shouldn’t want it or that it isn’t needed. Which, in my opinion does not sound like someone who is interested in developing software but stiffling it instead.
Please, don’t take it the wrong way…
I can generate a simple animation using Cool 3D and render it to a very “small” uncompressed AVI file maybe like 10 frames long, and you guys can give it the once over.
In the mean time you might want to check out the following:
As far as linux is concerned, only MPlayer seems to be able to run it correctly. OS X doesn’t seem to have any problem with it.
And moreover, Blender doesn’t load it correctly. That might be the biggest problem. To output 8 more bits per pixel probably wouldn’t have been hard, to rewrite the AVI input code would be harder.
If you’ve never used an AVI file with an alpha channel then there is no refference for your claim that Vegas handles the image sequences ‘with no problem at all’
I said it was my “preferred” way of rendering. Of course I’ve used Alpha channeled AVI. for “me” I’ve found that there are less problems with trying to correct interlacing problems. You said:
“most NLEs hate dealing with a bunch of small clips”
I was simply pointing out that in the case of Vegas that is not true. There is no problem at all “dealing with a bunch of small clips”. If you think Alpha channel AVIs have better quality, that is your preference.
Out of curiosity, if you had used an AVI file with an alpha channel, why didn’t you say so? I mean, that was a pretty big focal point of the thread up to that point…The question of whether or not an AVI file can support an alpha channel…If you had said you used one, I wouldn’t have assumed that you hadn’t based on your less than specific response.
My statements about the way Vegas handles multiple pictures was not based on prefference or personal opinion, but on benchmark results I performed before beginning work on a rather large project involving animations I produced in Cool 3D. I wanted to be sure I was doing things in a way that would make rendering and other aspects run as quickly as possible. I don’t remember the specific numbers, but I do remember choosing the AVI file with alpha channel method based on those results.
What kinds of interlace problems have you experienced with animation when imported into Vegas? I may be of some assistance.