Color accuracy and jit.gl.videoplane

Jun 15, 2006 at 9:49pm

Color accuracy and jit.gl.videoplane

Hi !

I am playing a movie in UYVY (PhotoJPEG, Optimal quality, 25fps) using jit.qt.movie and routed directly to a videoplane. But the colors of the movies are not exactly the sames, and it is most visible on black color (as movies are mainly black), which is no more real black but a very dark grey. Playing the movie in Quicktime Player give me a real black. I have set the erase_color to 0. 0. 0. 1. without change. Enabling lighting give me a slightly better result, but not yet what I see in quicktime player.

Questions :
1. have you already see that ?
2. does the use of uyvy may alter the colors ?
3. If yes to the above questions ;-), what are the correct settings to use ?

Thanks a lot

Laurent

#26439
Jun 15, 2006 at 10:14pm

Hi Laurent,
Please send along a patch that exhibits this problem and, if possible,
provide some of the media you are using (post online somewhere).
Otherwise, there is little we can do to help.

Cheers,
Andrew B.

#79045
Jun 15, 2006 at 10:56pm

#79046
Jun 15, 2006 at 11:03pm

Hi !

Here is a very simple patch I use but already has the problem :

max v2;
#N vpatcher 322 44 1350 909;
#P window setfont “Sans Serif” 9.;
#P message 427 143 33 196617 start;
#P message 396 143 29 196617 stop;
#P message 363 143 30 196617 read;
#P toggle 114 78 15 0;
#P newex 111 258 282 196617 jit.window vp @size 1280 656 @border 0 @colormode uyvy;
#P newex 114 183 236 196617 jit.gl.render vp @ortho 2 @erase_color 0. 0. 0. 1.;
#P newex 363 222 261 196617 jit.gl.videoplane vp @colormode uyvy @scale 1.95 1. 1.;
#P newex 114 136 58 196617 t b b erase;
#P newex 114 108 51 196617 qmetro 2;
#P newex 363 184 194 196617 jit.qt.movie 1280 656 @colormode uyvy;
#P connect 6 0 1 0;
#P connect 1 0 2 0;
#P fasten 2 2 4 0 167 171 119 171;
#P connect 2 0 4 0;
#P fasten 2 1 0 0 143 171 368 171;
#P connect 7 0 0 0;
#P fasten 8 0 0 0 401 177 368 177;
#P fasten 9 0 0 0 432 177 368 177;
#P connect 0 0 3 0;
#P pop;

A short sample movie I use on

http://www.ostiz.com/movie/BlackMovie.mov

Max/MSP 4.5.7, Jitter 1.5.2, Mac OS X 10.4.6, Quicktime Pro 7.1.1

Thanks for your help !

Laurent

#79047
Jun 15, 2006 at 11:55pm

Thank you all, it works !

Could be a good idea to put a paragraph on this topic in the next Jitter tutorial because I did not see anything about this in the manual, and it is quite hard to guess where is the problem !

Many thanks

Best regards

Laurent

#79048
Jun 16, 2006 at 8:35am

I second that – I wasn’t aware of this at all, it would be good to
have in the jit.qt.movie or jit.gl.videoplane help files!

Thanks,
Evan

#79049

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