Grab single image with jit.qt.grab - strange delay

Gert's icon

Hi,
I am very new to Max and Jitter and this is my first post here.

I am trying to grab still images with my webcam (built-in on macbook) and the jit.qt.grab object and have run into a strange problem I cannot get my head around:

The first two bangs I send to jit.qt.grab results in a black screen in my jit.pwindow. My third bang displays an image but it is the image grabbed on the second bang.

I have tried added print objects comming from both the jit.qt.grab and jit.pwindow objects and they show up in the max window so it looks like my flow is correct.

I am sure it it something simple but being a Jitter noob my debugging skills are not so good yet. Any help is appreciated.

Max Patch
Copy patch and select New From Clipboard in Max.

azs's icon

You are sending one bang to tell jit.qt.grab to grab a frame. The next bang grabs a new frame and outputs the old to the pwindow. So I guess you could try to image the frame sitting in jit.qt.grab, waiting to be pushed out by the next grabbed frame, or something like that...

Gert's icon

Aha I see - thank you for the explanation. Will try to figure out what to do from here, follow up questions are very likely

Thanks again.