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byronpetch
12-03-2003, 09:58 AM
Boy am I on a roll with questions at the moment. (BTW I do try to provide answers when I can too).

Does anybody know what is the best codec to use to increase render speeds. For example if I choose to render using the animation codec will a scene render faster than if I was to choose a motionJPEG or DV codec?

Also I noticed that DV footage rendered on PC is darker than the same scene rendered on Mac. Is this the same for other codecs?

Thanks

Matt

WizCraker
12-03-2003, 10:17 AM
Always render out to an Image Sequence [ie each image is saved with a number following the name, for instance fileName0001.tga, fileName0002.tga, etc...] This way if for any reason your render dies you can pick back up at the last rendered frame. If you render directly out to an animation file and start compressing it with a codec and the render dies you will have to start all over and you loose all previous frames.

To answer your question, no it will not speed up a render depending on the codec you choose.

If your footage is darker or brighter on differnt systems make sure your monitors are calibrated correctly. Or send the footage over to a .Production Monitor (http://www.bhphotovideo.com/bnh/controller/home?O=NavBar&A=search&Q=&ci=1981) [or a TV for the cheap] to make sure

Mylenium
12-03-2003, 11:03 AM
CoDecs are for transferring movie clips between systems ore generally making moving images viewable on your computer screen. They are little programs that analyse your footage and compress it more or less (thus saving disk space and lowering data transfer rates). Depending on how complex and sophisticated those algorithms are, this can take some time. Many algorithms also rely on analysing multiple frames to do compression (MPEG, DV) so this adds some slowdown as well. However, in comparison to the rendering itself the time required is barely noticeable, so don't expect speed gains by changing CoDecs. You can get some more speed by using a faster hard drive (the writing of the frame is a bit faster) but that's as good as it gets.

Like WizCraker said, it's best to render to image files and the create a clip using tools like Virtual Dub, Premiere or After Effects (to name but a few). This will also greatly boost your creative freedom since you can play around with different setting without lengthy renderings plus it will solve a part of your brightness/ gamma problem (but you will still have to calibrate your monitors properly). Most of the mentioned tools have some kind of test pattern along with some tweak buttons to set things up as needed.

Mylenium

ackees
12-03-2003, 01:38 PM
The difference between the Mac and the PC is the gamma of the monitor, PCs use a darker gamma, PCs also have a standard 96ppi while most Macs its 72ppi (I am not sure about the new G5s though). You can set the Mac to match the PC's gamma.