![]() However, for general everyday video use, you may feel comfortable ignoring them. Now, before everyone starts shooting off emails, let me stress that for some applications in certain situations even these codecs can be indispensable. Sorenson Video (but not Sorenson Video 3).And QuickTime supports all (or virtually all) its old codecs so that you can always play a QuickTime movie, no matter how old it is.Įxamples of less used (and notice I did not say “unnecessary”) codecs include: Both rapidly evolved into something much more, but neither forgot their roots.įinal Cut supports all the codecs that QuickTime ever supported. You’ve learned why there are so many codecs, however, Final Cut in some ways, makes selecting a codec even worse.įinal Cut started life as a QuickTime editor, the same way that Adobe Illustrator started life as a PostScript editor. There is no such thing as a “perfect” codec, as different codecs were created to meet different criteria. Each codec concentrates on maximizing one or two of the four. No one codec provides the best of all four of these criteria. TIFF and PNG are examples of a lossless codec.Ī lossy codec “throws out” visual information as part of the compression process, which means that the compressed image does not have the original quality of the source. They are designed to provide the highest image quality, but don’t compress or decompress image sequences in real-time.Īs a sidelight, codecs are often divided into “lossy” and “lossless.” A lossless codec preserves all the original image quality so that when an image is restored it is indistinguishable from the original. BMP, PNG, TGA and TIFF are special codecs used to save and restore still images. One last example, codecs are not just for moving images. On the other hand, if you are streaming a live event, the speed of compression is most important, because if you can’t compress faster than real-time, no one will be able to watch the event.Īs a third example, for a network television program, the speed of decompression and the quality of the final image are of paramount importance. That is not to say these last two are unimportant, just less important. ![]() ![]() There are four principal goals to consider when choosing a codec:įor instance, if you are posting a file to the Internet, the size of the file and the speed of decompression are more important than how long it takes to compress the file in the first place or the quality of the final image. A codec provides specific instructions on how to compress video to reduce its size, then decompress it to “full quality” for playback. That’s where codecs (short for: COmpressor/ DECompressor) come in. The reason for all this compression is that video files are HUGE and engineers are always looking for ways to make them smaller without sacrificing too much quality. Other video, like DigiBetacam is compressed less. Some video, like DV or HDV, is significantly compressed in a number of ways. This has been true since the beginning of time - or, well, the beginning of video at least. All Video is CompressedĪll video that we shoot on tape or watch on TV is compressed. This article will not cover those special codecs.īut, even with those restrictions, there’s still lots to talk about. However, I can help you understand what a codec does and how to choose one that will work for you.Īlso, capture card developers, such as Blackmagic Design and AJA, and camera manufacturers, such as Panasonic and Sony, often create their own codecs to take advantage of special technology built into their equipment. This is not an exhaustive discussion, as there are dozens and dozens of codecs with more sprouting up every day. Larry replies: Diane, email flame-throwing contests have started from much more innocent requests, but, what the heck, things are quiet at the moment. (By the way, I really really appreciated last month’s video processing tab discussion!) explain the sequence settings in the GENERAL tab? I have been unable to find a description of each of the compressors with info about its pros and cons or best use so that I can make a decision which is best. This technique grew out of a comment from Diane Thompson, who wrote: [ This article was first published in the June, 2006, issue of
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