I would be interested in adding to the information on this page. http://ffmpeg.sourceforge.net/compat.php I am no expert, but I sure have spent enough time fiddling around with things trying to get them to work. Making videos available for download on the web is still much too complicated. I use Linux and FreeBSD as my primary desktop systems, so I have no problem viewing most files, but most people are not so lucky. Many normal people don't click on video files because they are so sure they won't work. There should be some grid of pros and cons of different codec/container combinations. -- What default installations of what OS's can and can't play. -- What codec should be downloaded and where for each OS. -- Are there size or fps restrictions on some combination? -- Embedding the file vs. making it available for download The reason that I am posting this suggestion to ffmpeg-users is because in my experience most of the compatible codecs come from this code. I want more people to make sane educated decisions when preparing to make video files available for download on their websites rather than falling back on "easy" or broken solutions. I hope there are other people here who would would like to help to create such a resource. thanks for your time and suggestions, -- Marco