Gregory Maxwell wrote:
On Fri, Jul 31, 2009 at 9:51 PM, Michael Dalemdale@wikimedia.org wrote:
the transcode job into $wgChunkDuration length encoding jobs. ( each pieces is uploaded then reassembled on the server. that way big transcoding jobs can be distributed to as many clients that are participating )
This pretty much breaks the 'instant' gratification you currently get on upload.
true... people will never upload to site without instant gratification ( cough youtube cough ) ...
At any rate its not replacing the firefogg that has instant gratification at point of upload its ~just another option~...
Also I should add that this wiki@home system just gives us distributed transcoding as a bonus side effect ... its real purpose will be to distribute the flattening of edited sequences. So that 1) IE users can view them 2) We can use effects that for the time being are too computationally expensive to render out in real-time in javascript 3) you can download and play the sequences with normal video players and 4) we can transclude sequences and use templates with changes propagating to flattened versions rendered on the wiki@home distributed computer
While presently many machines in the wikimedia internal server cluster grind away at parsing and rendering html from wiki-text the situation is many orders of magnitude more costly with using transclution and temples with video ... so its good to get this type of extension out in the wild and warmed up for the near future ;)
The segmenting is going to significant harm compression efficiency for any inter-frame coded output format unless you perform a two pass encode with the first past on the server to do keyframe location detection. Because the stream will restart at cut points.
also true. Good thing theora-svn now supports two pass encoding :) ... but an extra key frame every 30 seconds properly wont hurt your compression efficiency too much.. vs the gain of having your hour long interview trans-code a hundred times faster than non-distributed conversion. (almost instant gratification) Once the cost of generating a derivative is on par with the cost of sending out the clip a few times for "viewing" lots of things become possible.
- I tie transcoded chunks to user ids this makes it easier to disable
bad participants.
Tyler Durden will be sad.
But this means that only logged in users will participate, no?
true... You also have to log in to upload to commons.... It will make life easier and make abuse of the system more difficult.. plus it can act as a motivation factor with distributed@home teams, personal stats and all that jazz. Just as people like to have their name show up on the "donate" wall when making small financial contributions.
peace, --michael