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| On May 13, 2014, at 1:16 PM, Jim Curtis wrote: > As I recall from many years ago, OMF was announced by Avid to be an Open (source) Media Framework that they hoped would be adopted by the world. > > That didn't happen. > > http://www.edlmax.com/FormatOmf.htm Right. Maybe you can fill me in on the history of OMF and we can use it as a cautionary tale. There doesn't seem to be a whole lot of info about it. Maybe that's part of the problem. I'm following the example set by OpenEXR for this, and in fact will use a lot of OpenEXR code in this project. A few things I think OpenEXR did right: 1. OpenEXR has a website. Simple enough, but you know exactly where to go for the latest information. Included on this website are links to sample files, right from the source. So you know if a program can't read one of those files, the problem is on the program's end. 2. OpenEXR is a container plus codecs. Containers like MXF, Matroska, MP4, and TIFF let you use any codec you want with them. So you may think you can read that random MXF into Premiere, but then it turns out you often can't, which I would find very frustrating. I don't think there's a program that can read every flavor of MXF, but the OpenEXR plug-in for After Effects can read virtually every EXR ever made. 3. OpenEXR has a high-quality open source software library that includes all the codecs. The library is very easy to use: just get the file, point to a pixel buffer, and read. It handles all the complexity on its own; you don't even have to know what a codec is. For example, when OpenEXR added support for tiles, people using the scanline API just had to update the the latest code and the library handled all the tiling business for them. They even did this with the recent addition of deep images. 3a. The OpenEXR library uses the BSD license. Some licenses like the GPL would prevent commercial programs from using the library. POM will only use code under the BSD license or similar. 4. OpenEXR is patent-free. Most of these MXF camera files use MPEG-2 or H.264 as their video compression format. But both of those are patent-encumbered so you can't just go make a program that uses those formats without going through legal hurdles. Not a problem with OpenEXR or POM. 5. OpenEXR is simple. It doesn't try to be a full-fledged media format, it just holds an image and metadata. The MXF container is a complex media format, but POM will only use it to create self-contained movies. Seems to me that OMF didn't have an open source library and probably used some sort of patent-encumbered video encoding. All they had was a spec and then demanded that developers write their own software to deal with it. OMF also tried to be a quasi-project file with transitions and such, forcing developers to handle that too. No wonder it wasn't widely adopted. Brendan |
