You can also “wrap” an MPEG-4 file in a QuickTime file with an mov extension, or encode it for Flash with an flv or f4v extension. When used in an MPEG-4 “wrapper,” H.264 files typically have an mp4 or m4v extension, the first being the official designation and the latter being the extension Apple created for its devices. MPEG-4 is the overarching standard that includes two video codecs, the MPEG-4 codec itself, and a more advanced video codec, H.264, also known as AVC. While producing podcasts is probably a tiny part of what we all do for a living, it’s still a useful skill, so I thought I would detail these findings for you.įirst, some background. After analyzing all the podcasts in Inlet HD’s most excellent streaming media analysis tool Semaphore, I noticed that many others used sub-optimal encoding parameters. Interestingly, six refused to load at all, and three had what I’ll call “compromised” displays. Having found the Mecca of H.264 usage, I decided to download 50 podcasts, try to load them on my iPod Nano and see what happened. It’s like finding Sox fans in Boston, Bulldog fans in Athens or Yankee fans in New Yawk. I say not surprisingly because iTunes is all about iPod/iPhone devices, which play only H.264 and MPEG-4 video. Not surprisingly, the market was podcasts distributed via iTunes. In one market segment, though, H.24 was near pervasive, so I decided to spend some time learning about how H.264 was used – and mis-used there. During my preparation, I noticed that while H.264 is the hot topic in periodicals and forums, it’s still not widely used for streaming, with Windows Media and VP6-based Flash still predominating. In the fall, of 2008, I gave a presentation on producing H.264 video at StreamingMedia West in San Jose.
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