[PD] gem save mov?

[chris clepper]

At 11:46 AM +0100 1/19/04, Julean Simon wrote:
>cgc,
>already tried it with pix_write, but it didnt do anything, attaching 
>a [file <test.jpg> <0>] to the [pix_write]. [auto 1] should actually 
>grab every pict or do i have to use a metro 25 bang?. is there an 
>example-patch somewhere, i guess i dont understand how it works.

try the example in 02.advanced/09.SnapshotSave.pd - hit the big bang 
to have it write a file to the pd/bin directory (not /tmp/gemshot). 
that patch can be simplified by just banging the pix_write object for 
each frame after initialization.  you can use the render_trigger 
object to have the capture occur every time the render chain is run 
or you can do async capture using a metro.

>i wanted to use 768 *576 (=pal) format and acceptable quality 
>because i intendet to re-read the sequence into the same patch later 
>and mix it with video.

NTSC SD (720x480 @ 30fps) is just barely possible on my 1ghz Tibook 
if the render patch is very lightweight.  This is under 10.2 though 
and I have heard that glReadPixels is much improved on 10.3 - the 
Apple engineers quoted a 3ms time to return the buffer on similar 
hardware.

>inputting video would have been my second question: i only managed 
>to read in a qt-mov, how would i get the video-signal from a  cam 
>connected via firewire?

use pix_video.  give the object arguments for the dimensions of your 
capture like: [pix_video 720 576] and it will grab a full PAL frame 
from the DV cam.  one thing to note is that for some reason QT has 
this 'high quality' flag for video capture that does contradictory 
things depending on what type of device you plug in.  if you use a FW 
webcam then send a 'quality 1' message followed by a 'reset' message 
to the object.  if you use a DV cam then do the same thing only with 
'quality 0'.  the difference is that the 1 level will be fast but 
interlaced and the latter will be a little slower but de-interlaced. 
1 is supposedly 'high quality' although I think interlaced DV looks 
very low quality.  oh well.

>thanx for taking the time. julean

you're welcome.

cgc