On 5/15/07, marius schebella marius.schebella@gmail.com wrote:
I was thinking Gem does not support all codecs.
GEM supports all Quicktime codecs on OSX, Directshow and Quicktime codecs on Windows and quite a few on Linux (depending on what libs you build).
with "faster" do you mean less cpu consuming? I thought the fastest/less
cpu consuming is a frame by frame codec like photo-jpeg because the gfx card can just take the jpegs and texture them onto a geo???
All codecs have to be decompressed into RAM and then uploaded to the graphics card.
maybe I was thinking of the isight, which uses uyvy, and a conversion
slows the process down.
The iSight might use 'Component' video UYVY but the conversion is pretty simple and fast. Often the device will do the conversion in hardware or the driver does it automatically. '2vuy' is probably the most universal format for YUV video.
since you are probably the only one who knows that, can you explain how
gem deals with the codecs? only if you have time... I do not understand why the apple intermediate should be faster for example when using the movie as a texture for a rectangle than the frame by frame jpeg compression?
Apple Intermediate Codec uses different code than Photo-JPEG for compression and decompression. In particular, Apple Intermediate is multi-threaded internally and it avoids some slow code that the JPEG codec uses.
I have started using AIC for work since it takes any video dimensions unlike HDV, DV or DVCPro. Those codecs are all faster than AIC at their native resolutions but are not flexible enough for some uses. Also, the DVCPro codecs only come with Final Cut and are not part of the standard Quicktime install. If you don't have Apple Intermediate then copy the codec from a mahcine that has it in /Library/Quicktime/ or install iMovie.