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alpha troubles - flickering (Read 739 times)
Steffen K
alpha troubles - flickering
Oct 21st, 2009, 9:22am  
Hi!

Im having a lot of trouble using video with alpha-channels.
Iv'e tried both Processings own vidio library and JMCvideo.

Every time i get something to work theres some heavy flickering going on..

Here's my attempt with JMCvideo:
Code:
import jmcvideo.*;
JMCMovie myMovie;

void setup() {
  size(500,500);
  myMovie = movieFromDataPath("5.mov");
  myMovie.loop();
}

void draw() {
  background(255);
  image(myMovie, 100, 100);
  myMovie.mask(myMovie);
}

JMCMovie movieFromDataPath(String filename)
{
  return new JMCMovie(this, filename, ARGB);
}



Anyone knows how to fix this issue?
Im in urgent need of help on this one...

Thanks,
Steffen
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subpixel
Re: alpha troubles - flickering
Reply #1 - Oct 22nd, 2009, 8:15am  
Steffen K wrote on Oct 21st, 2009, 9:22am:
Code:
  background(255);
  image(myMovie, 100, 100);
  myMovie.mask(myMovie);


Untested hypothesis:

Your draw() code reads as:

- white out the screen
- draw current frame
- apply blue channel of current frame as an alpha mask (see PImage.mask()) to the PImage (that the myMovie is a descendant of)

So... what happens when the next movie frame appears Do we get frame 2's RGB data with frame 1's B channel used for the alpha value Does this cause flickering.. or is it the "usual" (common) flickering seen when running Processing sketches

-spxl
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