jhave

i am trying to export a sequence of pngs 

from a webcam after doing a background subtract

exportimage works fine if go direct from cam into matrix

but the resulting png if i pass thru a jit.op @op- is grey

is this a limitation? or am i doing somethin wrong?

i am trying to export a sequence of pngs 
from a webcam after doing a background subtract

exportimage works fine if go direct from cam into matrix
but the resulting png if i pass thru a jit.op @op- is grey

exportimage-png-with-alpha-transparency

re:recording alpha-transparency pngs using exportimage after a jit.op @op-

i'd sincerely appreciate it if someone from Cycling could let me know if this is a limitation of Jitter 

or if its just the machine I am using (its a university box

I am facing a mild deadline and have reached the end of explorable options.

i'd sincerely appreciate it if someone from Cycling could let me know if this is a limitation of Jitter 
or if its just the machine I am using (its a university box
running MaxMSP 4.3.2

I'm not from Cycling, but I just tried your patch png export seemed 

to work fine for me on both the original image and a jit.op - 

modified image. I am running OS X 10.4.5 max 4.5.6 and jitter 1.5.2.

I'm not from Cycling, but I just tried your patch png export seemed  
to work fine for me on both the original image and a jit.op -  
modified image.  I am running OS X 10.4.5 max 4.5.6 and jitter 1.5.2.

question now is: is this 4.3.2 limitation?

or a bad codec on this particular machine?

thanks again, i'd been banging my head against the wall 

many thanks
very very helpful to know
(the pngs after op for me are just grey)

question now is: is this 4.3.2 limitation?
or a bad codec on this particular machine?

thanks again, i'd been banging my head against the wall 
thought i was doing something wrong...


This certainly has nothing to do with your version of Max, but might 

have something to do with your version of Jitter, which you haven't 

mentioned. It might also simply be a difference between the QuickTime 

version you are using (also not mentioned) and QuickTime 7, which 

Christopher Baker is using. It's also not clear what OS you're using, or 

what platform you are on. All of these factors could contribute to the 

You may find the BUG REPORTING GUIDELINES (copied below) helpful in 

formulating reports like this, since vague reports tend to fly under our 

Please report any problems you experience with clear and complete

information, including steps to reproduce, software and system

information, and where possible, an isolated example patch and crash

log. Something like the following would be ideal. This makes it

easier for us to find and fix the problems you experience. Without

such clear and complete information, it is less likely we will be

Provide a descriptive summary of the issue.

In numbered format, detail the exact steps taken to produce the bug.

Describe what you expected to happen when you executed the steps above.

Please explain what actually occurred when steps above are executed.

Describe circumstances where the problem occurs or does not occur,

such as software versions and/or hardware configurations.

Provide additional information, such as references to related

problems, workarounds and relevant attachments.

This certainly has nothing to do with your version of Max, but might 
have something to do with your version of Jitter, which you haven't 
mentioned. It might also simply be a difference between the QuickTime 
version you are using (also not mentioned) and QuickTime 7, which 
Christopher Baker is using. It's also not clear what OS you're using, or 
what platform you are on. All of these factors could contribute to the 
problem.

You may find the BUG REPORTING GUIDELINES (copied below) helpful in 
formulating reports like this, since vague reports tend to fly under our 
radar.

Please report any problems you experience with clear and complete
information, including steps to reproduce, software and system
information, and where possible, an isolated example patch and crash
log. Something like the following would be ideal. This makes it
easier for us to find and fix the problems you experience. Without
such clear and complete information, it is less likely we will be
able to.

Summary:
Provide a descriptive summary of the issue.

Steps to Reproduce:
In numbered format, detail the exact steps taken to produce the bug.

Expected Results:
Describe what you expected to happen when you executed the steps above.

Actual Results:
Please explain what actually occurred when steps above are executed.

Regression:
Describe circumstances where the problem occurs or does not occur,
such as software versions and/or hardware configurations.

Notes:
Provide additional information, such as references to related
problems, workarounds and relevant attachments.


(i did provide a patch, and tried to be clear)

and yes have now done a test on another machine

BUT without transparency (subtracted regions are simply black).

is there a methodology for exporting a movie or sequence of images with transparency ?

(i have investigated cv.jit and jitter help files and searched archives without any clear answers)

sorry if i deviated from the guidelines
(i did provide a patch, and tried to be clear)
and yes have now done a test on another machine
using same patch as posted before

(previous unsuccessful export 
machine was 
mac os 10.3, max 4.3.2, jitter 1.2.2.

successful test machine: 
windows xp, max 4.3.2, jitter 1.2.2)

So the png does export:
BUT without transparency (subtracted regions are simply black).

Looks like the difference is either platform or QuickTime version then.

If the QuickTime versions are identical on the 2 machines, then it's 

probably a Jitter issue (although we are no longer making updates to the 

Jitter 1.2.x code base). If not, you need to bring them into sync to 

test this out. I am 95% sure that this is going to turn out to be a 

If the QuickTime versions are identical on the 2 machines, then it's 
probably a Jitter issue (although we are no longer making updates to the 
Jitter 1.2.x code base). If not, you need to bring them into sync to 
test this out. I am 95% sure that this is going to turn out to be a 
QuickTime issue.

I will investigate Quicktime versions on both machines tomorrow and let you know how it works out.

In the meantime, my central more functional question remains:

is it possible export a png with transparency (in photoshop save-for-web this option is referred to as png-24 : Perhaps this codec is not possible to export with Jitter? )

Basically, I am seeking a way to export movies with transparency and assumed png sequences were the answer. I'd really appreciate it if anyone could let me know if this is a feasible path from a technnical standpoint.

In the meantime, my central more functional question remains:
is it possible export a png with transparency (in photoshop save-for-web this option is referred to as png-24 : Perhaps this codec is not possible to export with Jitter? )

Basically, I am seeking a way to export movies with transparency and assumed png sequences were the answer. I'd really appreciate it if anyone could let me know if this is a feasible path from a technnical standpoint. 

On Mar 7, 2006, at 2:06 AM, david jhave johnston wrote:

> In the meantime, my central more functional question remains:

> is it possible export a png with transparency (in photoshop save- 

> for-web this option is referred to as png-24 : Perhaps this codec 

> is not possible to export with Jitter? )

This should be possible provided it has been appropriately selected 

in the export image dialog (millions of colors +, should be 32 bit 

> Basically, I am seeking a way to export movies with transparency 

> and assumed png sequences were the answer. I'd really appreciate it 

> if anyone could let me know if this is a feasible path from a 

This can also be accomplished with jit.qt.record and any codec that 

supports an alpha channel such as animation or the several codecs 

>
> In the meantime, my central more functional question remains:
> is it possible export a png with transparency (in photoshop save- 
> for-web this option is referred to as png-24 : Perhaps this codec  
> is not possible to export with Jitter? )

This should be possible provided it has been appropriately selected  
in the export image dialog (millions of colors +, should be 32 bit  
with alpha)

> Basically, I am seeking a way to export movies with transparency  
> and assumed png sequences were the answer. I'd really appreciate it  
> if anyone could let me know if this is a feasible path from a  
> technnical standpoint.

This can also be accomplished with jit.qt.record and any codec that  
supports an alpha channel such as animation or the several codecs  
discussed at the following site.

very sorry to bother u again about something that must be quite simple...

but i have done a test exporting a chromakeyed movie from jit.qt.record using the "animation" codec,

is there a flag that needs to be set to enable alpha channel tranparency?

but i have done a test exporting a chromakeyed movie from jit.qt.record using the "animation" codec,
and the alpha channel is black

CORRECTION: animation codec does have an alpha channel....

CORRECTION: animation codec does have an alpha channel....
it just wasn't readable by sorenson.....

exportimage png with alpha transparency