Ruby-less way to add key frames to flv videos for the likes of JWPlayer

2 minutes, 2 seconds

At work we’ve been working on a good way to roll our own videos. We initially started with the generic off the shelf swf player + flv to make our videos go. This was OK, but was lacking some key features folks were used to, primarily full screen play back and the ability to seek to a specific spot in a video. Additionally, for videos that were over 20 minutes being viewed over slower connections, precious apache children would be chewed up potentially causing a slow down for the web head doing the serving.

Enter JWPlayer! This is a great, easy to configure, free for non-commercial use, flv player that offers the features we’re looking for. Further, we could offload the flv’s to our image server, lighttpd . (By the way lighttpd is extremely awesome; I can not recommend it enough. I first learned about from my friend over at WikiSpaces where they had dropped apache entirely in favor or lighttpd. Noteworthy is that lighttpd was first concieved as an attempted answer to the c10k problem. I’ve personally seen it handle over 2000 connections per minute and the server load didn’t go above 0.5 (though the full meaning of load average is a curious one (sorry for the double, now triple parenthetical statements )).) Simply add a little flv streaming foo to lighttpd, and you’re good to go.

At this point, we hit a stumbling block. In order for JWPlayer to seek, it would send a request for the FLV to the web server and give it a starting point, like so: lighttpd.domain.dom - [29/Jul/2009:12:46:37 -0700] 
"GET /web_assets/video/your.flv?start=17038076 HTTP/1.1" 200
 17765145 "-" "Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; 
en-US; rv: Gecko/20090715 Firefox/3.5.1"

However, if the flv you were serving didn’t have key frames then the web server would simply ignore the query string, and indeed, the click all together.

We do most of our development and video authoring on a mac and then serve our files off a load balanced linux server. At first, we used flvtool2 on linux to embed the key frames on our flvs. This kinda works, but it’d be easier to have the video author be able to add them himself with out needing to download and install ruby and rails and all that crazy server scripting foo. As his flv creator/codec/authoring app/chumpy wasn’t playing nice, I was given the task to find a simple solution.

Now, finally, we get to the point of the post. If you’ve gotten this far and wanna know how to embed keyframes with out ruby, get thee to the multi-platform, command line tool called flvmeta and go home happy!

Update: This post would not be complete without mentioned our use of swfobject to render the flash HTML.

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