[jitter] Colorchanneling with different pictures

jit.unpack/pack are not the fastest objects.  Probably the fastest
solution would use the GPU.  There are a few ways to do this:

1) Using colored planes with textures and additive blending
2) Using a custom shader to mix channels from several textures

Here's a patch that does 1)

#P window setfont "Sans Serif" 9.;
#P window linecount 2;
#P newex 336 318 261 196617 jit.gl.videoplane test @color 0 1 0 1
@depth_enable 0 @blend_enable 1 @blend_mode 6 1 @transform_reset 2;
#P flonum 535 228 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P window linecount 1;
#P message 535 249 42 196617 rate \$1;
#P message 398 225 80 196617 read dozer.mov;
#P message 469 249 27 196617 stop;
#P message 435 249 31 196617 start;
#P newex 336 248 41 196617 r draw;
#P message 499 249 31 196617 clear;
#P newex 336 276 103 196617 jit.qt.movie 320 240;
#B color 5;
#P window linecount 2;
#P newex 603 319 261 196617 jit.gl.videoplane test @color 0 0 1 1
@depth_enable 0 @blend_enable 1 @blend_mode 6 1 @transform_reset 2;
#P newex 72 318 261 196617 jit.gl.videoplane test @color 1 0 0 1
@depth_enable 0 @blend_enable 1 @blend_mode 6 1 @transform_reset 2;
#P flonum 802 229 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P window linecount 1;
#P message 802 250 42 196617 rate \$1;
#P message 665 226 83 196617 read dishes.mov;
#P message 736 250 27 196617 stop;
#P message 702 250 31 196617 start;
#P newex 603 249 41 196617 r draw;
#P message 766 250 31 196617 clear;
#P newex 603 277 103 196617 jit.qt.movie 320 240;
#B color 5;
#P flonum 271 229 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P message 271 250 42 196617 rate \$1;
#P message 134 223 81 196617 read wheel.mov;
#P message 205 250 27 196617 stop;
#P message 171 250 31 196617 start;
#P newex 72 249 41 196617 r draw;
#P message 235 250 31 196617 clear;
#P newex 72 277 103 196617 jit.qt.movie 320 240;
#B color 5;
#P message 147 103 34 196617 reset;
#P newex 147 123 186 196617 jit.gl.handle test @inherit_transform 1;
#P newex 12 123 48 196617 r render;
#P toggle 127 94 15 0;
#N vpatcher 53 128 279 297;
#P inlet 106 30 15 0;
#P window setfont "Sans Serif" 9.;
#P window linecount 0;
#P newex 43 95 47 196617 gate 1 1;
#P newex 42 116 41 196617 s draw;
#P window linecount 1;
#P newex 17 52 58 196617 t b b erase;
#P inlet 17 32 15 0;
#P outlet 17 83 15 0;
#P connect 1 0 2 0;
#P connect 2 0 0 0;
#P fasten 2 2 0 0 70 75 22 75;
#P connect 4 0 3 0;
#P fasten 5 0 4 0 111 88 48 88;
#P fasten 2 1 4 1 46 83 85 83;
#P lcolor 15;
#P pop;
#P newobj 65 123 42 196617 p Draw;
#P toggle 203 62 15 0;
#P message 203 82 68 196617 fullscreen \$1;
#N vpatcher 30 89 166 253;
#P window setfont "Sans Serif" 9.;
#P newex 50 71 35 196617 sel 27;
#P newex 50 50 40 196617 key;
#P outlet 50 93 15 0;
#P connect 1 0 2 0;
#P connect 2 0 0 0;
#P pop;
#P newobj 220 62 33 196617 p Esc;
#P newex 203 100 151 196617 jit.window test @depthbuffer 1;
#P toggle 65 75 15 0;
#P newex 65 94 57 196617 qmetro 30;
#P newex 65 150 187 196617 jit.gl.render test @erase_color 0 0 0 1;
#P connect 20 0 29 0;
#P connect 37 0 36 0;
#P fasten 36 0 30 0 540 270 341 270;
#P fasten 35 0 30 0 403 270 341 270;
#P fasten 34 0 30 0 474 270 341 270;
#P fasten 33 0 30 0 440 270 341 270;
#P fasten 31 0 30 0 504 270 341 270;
#P fasten 32 0 30 0 341 273 341 273;
#P connect 30 0 38 0;
#P connect 12 0 28 0;
#P fasten 14 0 12 0 77 274 77 274;
#P fasten 22 0 20 0 608 274 608 274;
#P fasten 21 0 20 0 771 271 608 271;
#P fasten 23 0 20 0 707 271 608 271;
#P fasten 24 0 20 0 741 271 608 271;
#P fasten 25 0 20 0 670 271 608 271;
#P fasten 26 0 20 0 807 271 608 271;
#P connect 27 0 26 0;
#P connect 19 0 18 0;
#P fasten 18 0 12 0 276 271 77 271;
#P fasten 17 0 12 0 139 271 77 271;
#P fasten 16 0 12 0 210 271 77 271;
#P fasten 15 0 12 0 176 271 77 271;
#P fasten 13 0 12 0 240 271 77 271;
#P connect 5 0 3 0;
#P connect 6 0 5 0;
#P connect 4 0 6 0;
#P connect 11 0 10 0;
#P fasten 8 0 7 1 132 116 102 116;
#P fasten 9 0 0 0 17 145 70 145;
#P connect 7 0 0 0;
#P fasten 10 0 0 0 152 145 70 145;
#P connect 1 0 7 0;
#P connect 2 0 1 0;
#P window clipboard copycount 39;