When I look inside an .AVI file which was output by Poser, I find that its component frames seem to have been compressed by a method called "Microsoft Video 1", and the text "CRAM" appears in the "type of compression" field in its "strf" chunks. Please where can I find the internal details of this "CRAM" compression method? How can I translate an image between this CRAM mode and ordinary uncompressed .BMP? I have got nowhere by looking in various WWW information sites, or trying to decipher the method directly by comparing a compressed file and an uncompressed file. I merely need the translation method :: I can write Windows programs.

Although I'm not 100% certain, I think that this is a Microsoft proprietary "standard". I fear that the only way to get details for this would be from Microsoft itself. Paul

But where from exactly within Microsoft? If I start at the home page http://www.microsoft.com , I am soon lost in an endless labyrinth of web pages about all sorts of irrelevant things.

Now there's a hole with no bottom grin I'm sorry, but the only suggestion I can make is to try starting with Technical Support or Licencing (if there is such an animal) Paul

Developer links are somewhere in there.

When you click 'Make a movie'and then click 'OK' you should get a window 'Video Compression' with a drop-down menu for 'compressor.' Scroll down to 'Uncompressed', which will not apply any compression to your movie. This should leave it as uncompressed bmp and you can then import it into Adobe Premiere or another NLE program. Let me know how it works out.

1. if you refer to extractinga bmp file out of an avi file, doesn't matter what created it. --then it is more that possible. 2. if you are reffering to compiling the said avi file with other files crreated by different software -- use premire5.5 to do it. 3. if, you just wanna know -- what on earth means "CRAM" then there are number of coices: a) since poser was oroginally meants for MAc, may be it referrs to MaC's way of treating avi files if they are to be converted from PC. b) if this file to be counterfeited, this mark means "a watermark feauture" to prove the authenticity c) "CRAM" in russian means "SHAME"

What is it exactly that you are trying to do? I would assume that CRAM is not the compression method, as Microsoft Video 1 is a video codec in itself, but perhaps it is the compression ratio. I found some white papers on Video capture, and the .AVI file format, there may be some useful information here: http://www.microsoft.com/hwdev/vidcap/#fPapers Also, here is another site that goes in depth into Video Compression codecs: http://www.codeccentral.com/Codecs/ Hope this helps you out. co(V)(V)union

If I tell Poser to output a video as .BMP (a) the file is far too big, and (b) I still have to compress it afterwards. I just want to write a program to do some simple work on .AVI files, but for that I need to know how "Microsoft Video 1" compression works.

Can't help ya there, but I will say that avi files are best manipulated as uncompressed, then compress the finished avi. This will give the best kwality. I know these can be very big, but I have a 20G drive. ;) And Microsoft usually won't give up much info without getting money, ie. getting the SDK. Have you tried using MPEG compression? Final quality is still very good, and it is much more accessable to the un-monied public.

Anthony, I would definitely suggest using a different codec for compression, as Microsoft Video 1 is limited to 1000's of colors, and the compression ratio is really outdated (originally written for Windows 3.x) I would also shy away from Cinepak, as it has really bad output quality. I wholly agree with MadRed about rendering to uncompressed video, and then trying different compression techniques using another video editing app such as Premiere, or ulead video studio. I have had pretty good luck with Indeo 5.0 video codecs, any of the quicktime (Sorenson etc.) or Motion JPEG all give a decent compression ratio, and excellent output quality. To add any of the above codecs to your rendering output options, just download and install the latest version of Quicktime (for .mov file output which is much better compression ratio to quality output than .avi) or download and install the latest Indeo codecs from: http://developer.intel.com/ial/indeo/video/driver.htm Hope this helps, co(V)(V)union

Go with Indeo. Indeo rules!

i.e. getting the SDK. Pleas, are these SDK's paper books or CD's or what? If they are books, please what is their publisher and full title and ISBN number, to make life easier for my bookseller? Have you tried using MPEG compression? As far as I know MPEG needs Quicktime, and Quicktime is notoriously incompatible with Netscape. There has been much discussion about this on the email group fab-ufo@lists.pipex.com (about the Gerry Anderson UFO series, archives on http://www.lists.pipex.com/cgi-bin/digests?list=fab-ufo ) when matters turned to people making .AVI's and .MPG's of scenes related to the series.

I live in England. I just asked at my local bookseller, and a computer search thru the titles of all books in print for the text strings "SDK" and "software development kit" (ignoring case of letters) yielded nothing that was in print and seemed relevant. Please, can I have more information about the various Microsoft SDK's and ehere and how to buy them??

Microsoft sells stuff like this (SDK) usually only to corporations, since it is very expensive, and you usually must have a team of programmers just to begin to understand it. Very likely this is well beyond your means, both financially and technically - no slur intended. I wasn't recommending you get it, just letting you know that the info is out there even if you and I (especially I) can't make good use of it. Trust me, if you can't find it, you probably can't use it. You will get more info thru the Net than you will from MS. It ain't known as the Evil Empire fer nuthin' !!!

So what exactly are you trying to do with AVI files? If you don't mind me asking. co(V)(V)union

So what exactly are you trying to do with AVI files? I merely wanted to have a go at writing a bit of software to handle them, perhaps to interface with a 2D graphics handling package called PPP that I wrote (see http://www.buckrogers.demon.co.uk/software/ppp.zip ). -It is less urgent now, as I now have got something of the hang of how to make AVIeditor work. But the information would still be useful. - I found late yesterday (by UK time) that the Windows Platform AVI can be downloaded from http://www.microsoft.com/msdownload/platformsdk/setuplauncher.htm (but it looks like a LONG-ISSIMO!!!! job, and at dialup line speed would be the sort of thing to leave running while you go out for a weekend scuba diving.)