I haven’t been super plugged into the blogosphere lately so I’m not sure if anyone’s done this or not, but here’s a look at what metadata is contained in the onMetaData callback of an mpeg4 video playing inside of the Adobe Flash Player “Moviestar” beta.
The mp4 file was transcoded using ffmpeg on the mac.
It kicks ass to have the “seekpoints” array of seekable times in the metadata, but I really wish there was an array of corresponding byte offsets so that it was possible to determine if the seekpoint you wish to jump to has actually been downloaded. I’d also like to know how and where metadata is stored in h264 containers and whether there are existing tools that would allow the *injection* of additional metadata.
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If you do find out a way to get those corresponding byte offsets, do let me know. I’m eager to see if I can do the same. Good luck!
Hi Brooks,
if you already know how to inject filepositions of seekpoints, please let me know.
Cheers,
Fabian
Brooks, your wish will become true, the final release will report the time along with the byte offset.
You can not inject this meta data yourself since the Flash Player merely reports the structure of an mp4 file as it is. What you will be able to modify are the tag properties in a file, f.ex. by using iTunes. You can also add timed text tracks using tools like mp4box.
Truth is that these specifications are so complex that no one supports 100% of it. I realize that it will be important for Adobe to communicate exactly what is and what is not supported. But this is a really big deal for Flash video and the online video market.
Adobe’s support for these standardized audio and video codes will streamline the production process for desktop and web video, hopefully reducing time-to-market and opening more video catalogs to online viewers. A beta version of the new player, Flash Player 9 Update 3 Beta 2 “Moviestar”, is available from Adobe Labs.
Thanks for informations..
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[...] Given the tumult of the change in my day job, it’s been difficult for me to keep up with the fallout of Adobe’s announcement of rudimentary support of AAC and h.264 codecs in a beta release of Flash Player 9. (For a start, you can read the formal announcement and/or the more technical explanation of the limitations from Tinic Uro, an engineer on the Player team.) In the two weeks hence, there’s been a lot of talk about the implications. As far as I can gather, no major player in web video has made the beta player a requirement to any public-facing player, but it wouldn’t surprise me if we see this soon - YouTube may have name recognition, but undoubtedly the video-on-the-web market is a cutthroat arena with many competitors. Of course, offering h.264 support means a potential migration from the current status quo - that of On2’s VP6 codec, supported in Flash Player since version 8. On2 of course isn’t taking all of this lying down. They’ve released an FAQ that highlights how sticking with their codec is still advantageous in specific scenarios. There’s even a community that prefers to sidestep the Flash Player entirely in favor of streaming DivX. Some even see Microsoft’s impact on the decision. But all said, there’s little question where the momentum lies given the rabid response to h.264’s inclusion into the Player. I’m excited to see where this goes. There’s already some interesting demos, write-ups and commentary on the subject and there’s certainly a lot of dust yet to settle, especially given Adobe’s related announcement of Flash Media Server 3. For those interested in exploring the new technology, understand that there are some important limitations to the beta release. Most noticeable is that only a subset of h.264 movies are currently playable. A significant number of encoding tools place the index information of an h.264 .mov file at the end of the file - this needs to be moved to the front in order for the file to be playable in a SWF. Renaun Erickson has created an AIR application which attempts to do this for you. For more information, begin with Tinic’s article, as well as an optimization note from Adobe. Also a note on metadata support. [...]