how to use jitter in conjunction with a webcam?

    Apr 18 2006 | 10:02 am
    I'm a student and a beginner for Max/MSP/Jitter. my laptop is a PC and running a windows system.My Max Version is 4.5.1 and Jitter is 1.2.3(demo).
    I'm trying to use a webcam (Logitech QuickCam) to capture the shadows of people.
    I found the relevant topic in Tutorial 21 in Jitter Tutorial and topics. When I opened the 21jSequenceGrabbers.pat in Max/MSP, there were 3 examples. I double clicked on P example_1 , then a new window was opened. There was nothing happened when I clicked the getvdevlist message box to cause the Jit.qt.grab object to search for available video capture device. Is it the right way to connect jitter with a webcam?
    The tutorial says( for my vesion) that Jit.qt.grab object requires a Quicktime and a 3 rd party QuickTime VDIG component under Windows. I have download a VDIG component at and installed it at C://program files/ WinVDIG/. And I also have a QuickTime Player 7 which is installed at C://program files/Quicktime/. Now there are my questions:
    1. Is the QuickTime supposed to be QuickTime pro 7?
    2. Do you think the QuickTime 7 is matching my Max/MSP/Jitter version?
    3. What do you think about "under Windows"? Do you think the two things(QuickTime and VDIG) should be in C://Windows directory?
    Any help would be greatly appreciated!

    • Apr 18 2006 | 11:03 am
      replace jit.qt.grab with jit.dx.grab no need for winvdig
    • Apr 18 2006 | 11:25 am
      Thanks for quick response!
      I changed the jit.qt.grab with jit.qx.grab, however, the max window print ?error: jit.qx.grab: no such object. It is might because my lower Max/MSP/Jitter vesion? My Max/MSP version is 4.5.1 and jitter 1.2.3 (demo).
    • Apr 18 2006 | 11:39 am
      i'd try the jit.DX.grab object if i were you
      that means it uses the directShow drivers instead of the quicktime framegrabber to import frames from live video devices. And directshow comes packed with microsoft directx, which you most probably have installed already. otherwise you can download the latest version from the microsoft support pages. just google for 'download directx'
    • Apr 18 2006 | 11:57 am
      Thanks, Mojo.
      I changed the jit.qt.grab object with jit.dx.grab object. But the max window also showed ?error: jit.dx.grab: no such object. I cheaked my program file and there's a Microsoft DirectX 9.0 SDK Undate (December 2004). Is the microsoft directx you point to?
    • Apr 18 2006 | 12:12 pm
      thats the object you need. The directx version you have installed shouldnt be a problem. Make sure that the folders max is searching through contains the folder where the jitter objects are installed (think thats under options or preferences > folder preferences)
      maybe, just try opening a new patch, add an object by right clicking> new object >... if you don't see any jitter objects mentioned there, its probably jitter that aint installed correctly.
      another thing you can try is, when you added the jit.dx.grab object to a patching, hold ALT + click the object, this opens a tutorial patch concerning this object...
      hope this helps u out
    • Apr 18 2006 | 2:03 pm
      Thank you, Mojo.
      I have cheaked and made sure that JitterReference folder is under the patches folder (Please see the attached jpeg 18042006_01).
      When i do right clicking to open a new object menu, there are jitter objects there, however, i can't find the jit.dx.grab object.(please see 18042006_02)
      Please see the max window print errors: no such object. Do you think it is because my lower jitter version?
    • Apr 18 2006 | 2:18 pm
      This is the second picture 18042006_02
    • Apr 18 2006 | 2:46 pm
      your lower jitter version is indeed the only issue left that could cause the jit.dx.grab object not to be found.
      the jit.dx.grab object was included since the 1.5 edition of jitter...
      so updating is the message... if that wont work you can still try using jit.qt.grab, but i'm also a windows user and its quite a bit harder to do than the dx part because the needed quicktime components arent available anymore in the latest version of quicktime (which comes packed with itunes), although FULL versions of quicktime can still be found on the net, which contain the capturing libraries needed. (Also vdig -or something like that- should be installed, but i read you already knew that)
      grtz d
    • Apr 19 2006 | 1:57 pm
      Dear mojo,
      I solved my problem finally. I reinstalled WinVDIG with a lower version 1.0.1 and QuickTime 6.0.2. Now they are working!
      Thank you for your help and I learned a lot from you!
      Regards from amy
    • Apr 19 2006 | 2:00 pm
      you're more than welcome amy!