Forums > Jitter

painting with feedback in jitter

May 14, 2007 | 4:40 pm

Hi I am still trying to get a patch that will give me very long feedback times, the closest I have come is the jit.slide object however I can’t get the feeback long enough, I want it to remain for at least 20 secs at the moment I can only ramp it up to a sec.

I found this in the forum history
——————————————————–
Greetings all

I am trying to figure out how to create an effect where essentially I add frames together –

that is to say I want to use a live camera feed to shoot a moving LED in the dark and end up with long traces from the path of the light source…
I looked at some delays and feedback but it’s not really what I am looking for…
you can get something like this effect by using a DV cam with controllable frame rate – 4fps will make this show up a bit…

an suggestions about how to do this?

thanks
jamie

Report message to a moderator

Re: adding frames – light streaks? [message #102956 is a reply to message #102952 ] Sun, 29 April 2007 00:45
yair r.
Messages: 382
Registered: June 2005
Senior Member
add to buddy list
ignore all messages by this user
jitter has many ready objects to do this.
one tip is if you choose to use jit.slide, turn your matrix into float32
before the slide, the float32 precision will give you a longer trail, yes.
[jit.matrix 1 float32 320 240 @adapt 0] > [jit.slide @slide_up 10
@slide_down 500]
i haven’t tested this but see if you get something

On 4/29/07, jamie jewett wrote:
>
> Greetings all
———————————————————–
However i can’t get this modification to work I just keep getting a white screen,
totally stuck
freya


May 14, 2007 | 4:58 pm

you should look at Dan Wincklers Brush http://danwinckler.com/blog/
archives/2006/04/07/brush_012/ and you could easily modify the
feedback for float32 for looonnngggg feedback intervals.

On May 14, 2007, at 12:40 PM, freya smith wrote:

>
> Hi I am still trying to get a patch that will give me very long
> feedback times, the closest I have come is the jit.slide object
> however I can’t get the feeback long enough, I want it to remain
> for at least 20 secs at the moment I can only ramp it up to a sec.
>
> I found this in the forum history
> ——————————————————–
> Greetings all
>
> I am trying to figure out how to create an effect where essentially
> I add frames together -
>
> that is to say I want to use a live camera feed to shoot a moving
> LED in the dark and end up with long traces from the path of the
> light source…
> I looked at some delays and feedback but it’s not really what I am
> looking for…
> you can get something like this effect by using a DV cam with
> controllable frame rate – 4fps will make this show up a bit…
>
> an suggestions about how to do this?
>
> thanks
> jamie
>
>
> Report message to a moderator
>
> Re: adding frames – light streaks? [message #102956 is a reply to
> message #102952 ] Sun, 29 April 2007 00:45
> yair r.
> Messages: 382
> Registered: June 2005
> Senior Member
> add to buddy list
> ignore all messages by this user
> jitter has many ready objects to do this.
> one tip is if you choose to use jit.slide, turn your matrix into
> float32
> before the slide, the float32 precision will give you a longer
> trail, yes.
> [jit.matrix 1 float32 320 240 @adapt 0] > [jit.slide @slide_up 10
> @slide_down 500]
> i haven’t tested this but see if you get something
>
> On 4/29/07, jamie jewett wrote:
>>
>> Greetings all
> ———————————————————–
> However i can’t get this modification to work I just keep getting a
> white screen,
> totally stuck
> freya
>
>
>
>

v a d e //

http://www.vade.info
abstrakt.vade.info


May 14, 2007 | 5:08 pm

have you experimented with something like this?:

max v2;
#N vpatcher 10 59 716 606;
#P user jit.pwindow 78 278 322 242 0 1 0 0 1 0;
#P window setfont "Sans Serif" 9.;
#P window linecount 1;
#P message 267 173 50 196617 xfade $1;
#P flonum 267 151 50 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
#N vpatcher 20 74 620 474;
#P outlet 117 62 15 0;
#P inlet 117 39 15 0;
#P connect 0 0 1 0;
#P pop;
#P newobj 93 235 37 196617 p thru;
#P newex 79 209 115 196617 jit.xfade @xfade 0.995;
#P flonum 154 100 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P message 154 120 42 196617 rate $1;
#P message 214 100 28 196617 read;
#P toggle 79 100 15 0;
#P newex 79 120 52 196617 metro 33;
#P newex 79 157 103 196617 jit.qt.movie 320 240;
#B color 5;
#P connect 2 0 1 0;
#P fasten 1 0 0 0 84 150 84 150;
#P fasten 3 0 0 0 219 147 84 147;
#P fasten 4 0 0 0 159 147 84 147;
#P connect 0 0 6 0;
#P fasten 9 0 6 0 272 193 84 193;
#P connect 6 0 10 0;
#P fasten 6 0 7 0 84 229 98 229;
#P connect 5 0 4 0;
#P fasten 7 0 6 1 98 257 199 257 199 202 189 202;
#P connect 8 0 9 0;
#P pop;

freya smith schrieb:
> Hi I am still trying to get a patch that will give me very long feedback times, the closest I have come is the jit.slide object however I can’t get the feeback long enough, I want it to remain for at least 20 secs at the moment I can only ramp it up to a sec.
>
> I found this in the forum history
> ——————————————————–
> Greetings all
>
> I am trying to figure out how to create an effect where essentially I add frames together –
>
> that is to say I want to use a live camera feed to shoot a moving LED in the dark and end up with long traces from the path of the light source…
> I looked at some delays and feedback but it’s not really what I am looking for…
> you can get something like this effect by using a DV cam with controllable frame rate – 4fps will make this show up a bit…
>
> an suggestions about how to do this?
>
> thanks
> jamie
>
>
> Report message to a moderator
>
> Re: adding frames – light streaks? [message #102956 is a reply to message #102952 ] Sun, 29 April 2007 00:45
> yair r.
> Messages: 382
> Registered: June 2005
> Senior Member
> add to buddy list
> ignore all messages by this user
> jitter has many ready objects to do this.
> one tip is if you choose to use jit.slide, turn your matrix into float32
> before the slide, the float32 precision will give you a longer trail, yes.
> [jit.matrix 1 float32 320 240 @adapt 0] > [jit.slide @slide_up 10
> @slide_down 500]
> i haven’t tested this but see if you get something
>
> On 4/29/07, jamie jewett wrote:
>> Greetings all
> ———————————————————–
> However i can’t get this modification to work I just keep getting a white screen,
> totally stuck
> freya
>
>
>
>
>


May 14, 2007 | 5:36 pm

have downloaded brush but couldn’t modify it for float 32 same problem as before everything goes white when i try. So I must be getting it wrong.


May 14, 2007 | 5:36 pm

freya smith skrev:
> Hi I am still trying to get a patch that will give me very long feedback times, the closest I have come is the jit.slide object however I can’t get the feeback long enough, I want it to remain for at least 20 secs at the moment I can only ramp it up to a sec.
>
> I found this in the forum history
> ——————————————————–
> Greetings all
>
> I am trying to figure out how to create an effect where essentially I add frames together –
>
> that is to say I want to use a live camera feed to shoot a moving LED in the dark and end up with long traces from the path of the light source…[...]
> ———————————————————–
> However i can’t get this modification to work I just keep getting a white screen,
> totally stuck
> freya
>
Hej Freya,
What’s happening here is just the patch doing its thing – if you add
together the brightness of several layers of old video, then you
inevitably get a fully white screen. Just as if you set an audio delay
to feedback you get a massive wall of noise, eventually.

What I suggest you do is simply reduce the framerate of the delay, that
way you will be able to feed it back for a long time without
over-exposing the image like this.

Andreas.3


May 14, 2007 | 5:38 pm

Thanks john yeah I have, I have been using otherpeoples patches as they seem to have parameters for definition too so I don’t end up with a black screen at high feedback settings.
I must be honest I am finding this all a bit hit and miss at the moment, it was all so easy with audio, video seems so much more complex.
freya


May 18, 2007 | 2:34 am

For what it’s worth, here’s an example of how to make long feedback
trails with floating point textures on the graphics card (provided
that your card supports floating point textures). I was testing some
things in the forthcoming release and got sucked into watching
psychedelic spray foam videos through this sort of temporal low pass
filter. While zoning out on the fascinating motion, I remembered
this thread. Maybe it’s of use to someone, maybe not.

Key tricks in this patch are to use @type float for the slabs which
do the processing, then use @type char for the final slab before
applying to geometry so that it will work on windows NVidia cards and
you can get texture interpolation on display.

Btw, if things are just "going to white" as you described, it sounds
like you need to increase your "slide_up" factor as well. Might be
worth doing some color adjustment *before* the feedback as well as
after the feedback.

-Joshua

#P window setfont "Sans Serif" 9.;
#P window linecount 1;
#P newex 410 240 69 196617 loadmess 1.5;
#P newex 486 240 80 196617 loadmess -0.25;
#P newex 425 124 72 196617 loadmess 500;
#P newex 348 124 66 196617 loadmess 40;
#P window linecount 3;
#P comment 405 165 330 196617 use floating point textures for the
output and feedback stages of the slide processing so that long
slides will not suffer due to quantization error;
#P window linecount 1;
#P newex 410 304 76 196617 prepend param;
#P flonum 486 262 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P message 486 283 43 196617 bias $1;
#P flonum 410 262 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P message 410 283 48 196617 scale $1;
#P newex 158 338 220 196617 jit.gl.slab fa @type char @file
cc.scalebias.jxs;
#P newex 254 200 76 196617 prepend param;
#P newex 158 263 120 196617 jit.gl.slab fa @type float;
#P flonum 317 158 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P message 317 179 75 196617 slide_down $1;
#P flonum 254 158 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P message 254 179 62 196617 slide_up $1;
#P message 168 202 67 196617 getparamlist;
#P newex 21 145 70 196617 jit.window fa;
#P newex 158 381 190 196617 jit.gl.videoplane fa @transform_reset 2;
#P newex 21 123 121 196617 jit.gl.render fa @ortho 2;
#P newex 21 79 58 196617 t b b erase;
#P newex 158 232 200 196617 jit.gl.slab fa @file tp.slide.jxs @type
float;
#P message 274 75 27 196617 stop;
#P flonum 302 55 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P message 302 75 42 196617 rate $1;
#P message 242 75 28 196617 read;
#P flonum 62 37 35 9 0.5 0 1 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P toggle 21 37 15 0;
#P newex 21 58 51 196617 qmetro 2;
#P newex 158 127 155 196617 jit.qt.movie @adapt 1 @unique 1;
#P window linecount 5;
#P comment 397 339 330 196617 this stage is important to convert to
char texture for windows NVidia cards , and on all platforms to
enable texture interpolation (floating point textures typically will
not support interpolation , so are best used for processing data
rather than final texture application). here we throw in a bit of
color processing just for fun;
#P connect 3 0 2 0;
#P connect 2 0 10 0;
#P connect 10 0 11 0;
#P fasten 10 2 11 0 74 105 26 105;
#P connect 4 0 2 1;
#P fasten 5 0 1 0 247 117 163 117;
#P fasten 8 0 1 0 279 117 163 117;
#P fasten 6 0 1 0 307 117 163 117;
#P fasten 10 1 1 0 50 117 163 117;
#P connect 1 0 9 0;
#P fasten 20 0 9 0 259 223 163 223;
#P fasten 14 0 9 0 173 223 163 223;
#P connect 9 0 19 0;
#P connect 19 0 21 0;
#P fasten 26 0 21 0 415 331 163 331;
#P connect 21 0 12 0;
#P connect 28 0 16 0;
#P connect 16 0 15 0;
#P connect 15 0 20 0;
#P fasten 17 0 20 0 322 198 259 198;
#P connect 7 0 6 0;
#P connect 29 0 18 0;
#P connect 18 0 17 0;
#P fasten 19 0 9 1 163 292 391 292 391 226 353 226;
#P connect 31 0 23 0;
#P connect 23 0 22 0;
#P fasten 24 0 26 0 491 302 415 302;
#P connect 22 0 26 0;
#P connect 30 0 25 0;
#P connect 25 0 24 0;
#P window clipboard copycount 32;


May 18, 2007 | 2:27 pm

nice little patch, mr. clayton
cheers
bruce

On May 17, 2007, at 10:34 PM, Joshua Kit Clayton wrote:

> here’s an example of how to make long feedback trails with floating
> point textures

bruce tovsky
http://www.skeletonhome.com

"Flying is learning how to throw yourself at the ground and miss."
Douglas Adams


May 18, 2007 | 6:11 pm

I’m a jitter n00b, so this might be really dumb, but if you’re trying
to track led’s in the dark, couldn’t use a comparitive operator?
Like, if a pixel is darker than a specified amount, set it to black,
and if it exceeds the amount, then pass it to the matrix. That way
the dark parts would stay dark every time a new frame is drawn and the
ambient light wouldn’t be able to add up. Would something like that
work?

Bryan

http://www.techniquolor.com

http://www.ksod.net


May 18, 2007 | 6:34 pm

jit.op @op > @val whateveryouwanthere ???

On May 18, 2007, at 2:11 PM, Bryan Teoh wrote:

> I’m a jitter n00b, so this might be really dumb, but if you’re trying
> to track led’s in the dark, couldn’t use a comparitive operator?
> Like, if a pixel is darker than a specified amount, set it to black,
> and if it exceeds the amount, then pass it to the matrix. That way
> the dark parts would stay dark every time a new frame is drawn and the
> ambient light wouldn’t be able to add up. Would something like that
> work?
>
> Bryan
> —
> http://www.techniquolor.com
> http://www.ksod.net

v a d e //

http://www.vade.info
abstrakt.vade.info


May 18, 2007 | 7:42 pm

On May 18, 2007, at 11:34 AM, vade wrote:

> jit.op @op > @val whateveryouwanthere ???

Probably want "@op >p". i.e. "greaterthanpass", or can use
jit.lumakey or similar for a "soft-knee". I’d also mention that the
jit-diy-chromakey.pat example patch demonstrates some build it
yourself keying strategies if these others aren’t specifically suited
to the task.

-Joshua


May 18, 2007 | 8:06 pm

Very. Unfortunately it didn’t work for me until I removed the top "@type
float" from the slab.

any idea why?

Andreas.

bruce tovsky skrev:
> nice little patch, mr. clayton
> cheers
> bruce
>
> On May 17, 2007, at 10:34 PM, Joshua Kit Clayton wrote:
>
>> here’s an example of how to make long feedback trails with floating
>> point textures
>>
>
> bruce tovsky
>
> http://www.skeletonhome.com
>
>
> "Flying is learning how to throw yourself at the ground and miss."
>
> Douglas Adams
>
>
> ————————————————————————
>
>


May 18, 2007 | 8:41 pm

On May 18, 2007, at 1:06 PM, Andreas Wetterberg wrote:

> Very. Unfortunately it didn’t work for me until I removed the top
> "@type float" from the slab.
> any idea why?

Floating point textures aren’t supported on all graphics cards. OS,
GPU + driver version, jitter version would be good things to know to
establish why it’s not working for you.

For example, it won’t work on the Intel GMA 950 GPU, as exists on the
standard MacBook, the MacMini, and many laptop PCs. For OS X, here’s
one nice chart. The thing to look for for is ARB_texture_float or
similar ATI, NVidia, or Apple vendor specific flags.

For Apple there’s this handy chart:

http://homepage.mac.com/arekkusu/bugs/GLInfo.html

For either platform, there’s either the command line glew (OpenGL
Extensions Wrangler) or more user friendly GUI based glview (OpenGL
Extensions Viewer):
http://glew.sourceforge.net/

http://www.realtech-vr.com/glview/

If you don’t feel like getting dirty with extensions, the short of it
is that floating point textures should work on either platform with
the ATI 9600 Radeon or higher, NVidia GeForce 6000 series or higher,
or Intel GMA 3000 series or higher. There’s a few lower end cards
from some of these vendors for which it will also work, but I
generally wouldn’t recommend them for this sort of thing. If you have
a Windows machine and it doesn’t work with these cards, I’d recommend
you try upgrading the OpenGL drivers.

Hope this helps.

-Joshua


May 18, 2007 | 9:44 pm

Hi Joshua,

I wish I could blame my graphics processor, but I am sure that’s not it…

WinXP sp2, Core2Duo 6600 @ 2.4 ghz , 2gb ram

Nvidia GeForce 8800 GTS – (*ever so slightly* overclocked – core@700mhz,
memory bus@818 mhz… I tried it without the overclock too.)
MaxMSP 4.6.*2* – yes, haven’t upgraded yet ;)
Jitter 1.6.3b2

- I’ve discovered that deleting and then re-inserting the second slab
appeared to solve the problem, for some strange reason.

Thanks for this patch, this is such a cool lil’ thing to have laying
around, and lord knows I need to use more shader/slab gizmo-doodads :)

Andreas.

Joshua Kit Clayton skrev:
>
> On May 18, 2007, at 1:06 PM, Andreas Wetterberg wrote:
>
>> Very. Unfortunately it didn’t work for me until I removed the top
>> "@type float" from the slab.
>> any idea why?
>
> Floating point textures aren’t supported on all graphics cards. OS,
> GPU + driver version, jitter version would be good things to know to
> establish why it’s not working for you.
>
> For example, it won’t work on the Intel GMA 950 GPU, as exists on the
> standard MacBook, the MacMini, and many laptop PCs. For OS X, here’s
> one nice chart. The thing to look for for is ARB_texture_float or
> similar ATI, NVidia, or Apple vendor specific flags.
>
> For Apple there’s this handy chart:
> http://homepage.mac.com/arekkusu/bugs/GLInfo.html
>
> For either platform, there’s either the command line glew (OpenGL
> Extensions Wrangler) or more user friendly GUI based glview (OpenGL
> Extensions Viewer):
> http://glew.sourceforge.net/
> http://www.realtech-vr.com/glview/
>
> If you don’t feel like getting dirty with extensions, the short of it
> is that floating point textures should work on either platform with
> the ATI 9600 Radeon or higher, NVidia GeForce 6000 series or higher,
> or Intel GMA 3000 series or higher. There’s a few lower end cards from
> some of these vendors for which it will also work, but I generally
> wouldn’t recommend them for this sort of thing. If you have a Windows
> machine and it doesn’t work with these cards, I’d recommend you try
> upgrading the OpenGL drivers.
>
> Hope this helps.
>
> -Joshua
>
> .
>


May 19, 2007 | 5:04 am

On May 18, 2007, at 2:44 PM, Andreas Wetterberg wrote:

>
> – I’ve discovered that deleting and then re-inserting the second
> slab appeared to solve the problem, for some strange reason.

Thanks for the follow up. Glad you found a workaround in the
meantime. If you can determine a general pattern with floating point
textures and this sort of behavior on your graphics card, please let
us know so that we can investigate it further.

Thanks,
Joshua


June 1, 2007 | 10:50 pm

Joshua Kit Clayton wrote:
>
> On May 18, 2007, at 1:06 PM, Andreas Wetterberg wrote:
>
>> Very. Unfortunately it didn’t work for me until I removed the top
>> "@type float" from the slab.
>> any idea why?
>
> Floating point textures aren’t supported on all graphics cards. OS,
> GPU + driver version, jitter version would be good things to know to
> establish why it’s not working for you.
I wrote:
> Hi Joshua,
>
> I wish I could blame my graphics processor, but I am sure that’s not
> it…
>
> WinXP sp2, Core2Duo 6600 @ 2.4 ghz , 2gb ram
Time to revisit this thing… and these results are weeeeird:
Using @type float doesn’t work at all, but when I type in @type char OR
@type float64 everything works perfectly!

Could that be because it’s a really new card?

Best,
Andreas.


June 1, 2007 | 11:24 pm

On Jun 1, 2007, at 3:50 PM, Andreas Wetterberg wrote:

> Time to revisit this thing… and these results are weeeeird:
> Using @type float doesn’t work at all, but when I type in @type
> char OR @type float64 everything works perfectly!

Probably since float64 is not a supported texture type it is
defaulting to char in that case.

> Could that be because it’s a really new card?

Perhaps something related to the driver settings, but there might be
other issues with our implementation of floating point textures in
certain situations. These issues won’t be fixed before Max 5,
unfortunately, but if you place a bug report with support we’ll try
to get them solved for the next big Jitter release.

-Joshua


June 1, 2007 | 11:41 pm

Joshua Kit Clayton skrev:
>
> On Jun 1, 2007, at 3:50 PM, Andreas Wetterberg wrote:
>
>> Time to revisit this thing… and these results are weeeeird:
>> Using @type float doesn’t work at all, but when I type in @type char
>> OR @type float64 everything works perfectly!
>
> Probably since float64 is not a supported texture type it is
> defaulting to char in that case.
Ah – the odd thing – just testing this – is that when you
alt-right-click the object it will display
[type=whatever-strange-message-you-send-it]
>
>> Could that be because it’s a really new card?
>
> Perhaps something related to the driver settings, but there might be
> other issues with our implementation of floating point textures in
> certain situations. These issues won’t be fixed before Max 5,
> unfortunately, but if you place a bug report with support we’ll try to
> get them solved for the next big Jitter release.
>
> -Joshua
I definitely will do – thankfully the patch still looks stunning to my
newbie eyes, so I’m not fretting at all.
Andreas.


June 1, 2007 | 11:58 pm

On Jun 1, 2007, at 4:41 PM, Andreas Wetterberg wrote:

> I definitely will do – thankfully the patch still looks stunning to
> my newbie eyes, so I’m not fretting at all.

Yes, it will work fine, but you won’t be able to have *really* long
feedback without using floating point numbers.

-Joshua


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