Quartz Compositor or Cocoa or ?

Discussion in 'Mac Programming' started by Flynnstone, Oct 10, 2007.

  1. Flynnstone macrumors 65816

    Flynnstone

    Joined:
    Feb 25, 2003
    Location:
    Cold beer land
    #1
    I've been playing with Quartz Compositor (QC). Cool.
    Can I make an application with QC?
    I am looking at using it to do real time video overlays and other stuff.
    What is the best way to approach this?

    I'm definitely a Cocoa newb. I know C and RealBasic. I typically write code for embedded systems to give some background on me. So I'm used to tickling hardware with C. The level of sophistication with QC is amazing to say the least.

    Any guidance would be appreciated.

    Tim
     
  2. kainjow Moderator emeritus

    kainjow

    Joined:
    Jun 15, 2000
    #2
    Quartz Composer is pretty powerful. I've only played with it a little so I don't know its full potential. You can interface .qtz files with Cocoa relatively easily and interact with them. So what you want to do is probably possible with a combination of both, but I wouldn't be the one to tell you how to do it :)

    Core Animation in Leopard might make this easier, but I haven't dabbled in that much either beyond the basics (and unfortunately can't go into much specifics on it yet).
     
  3. Flynnstone thread starter macrumors 65816

    Flynnstone

    Joined:
    Feb 25, 2003
    Location:
    Cold beer land
    #3
    Thanks for the reply.

    Basically I'm looking at doing something like a video screen in a convenience store that shows multiple cameras on one screen with a text overlay.
    But, (always a but) the cameras will be at least High Def (HD, 1080p) and likely higher. Also, simple text overlay with real time information and likely a 3D graphic arrow or something like that showing say a pointer to the direction north.

    Where can I go to get more info on combining Cocoa and Quartz Compositor. Or wait a bit of time for Leopard to be released?
     
  4. Flynnstone thread starter macrumors 65816

    Flynnstone

    Joined:
    Feb 25, 2003
    Location:
    Cold beer land
  5. kainjow Moderator emeritus

    kainjow

    Joined:
    Jun 15, 2000
    #5
    The number of Cocoa developers on MR is pretty small, from what I've seen in the responses. You may be better off finding more info on the mailing lists.
     
  6. Nutter macrumors 6502

    Joined:
    Mar 31, 2005
    Location:
    London, England
    #6
    I'm using Quartz Composer. It's awesome stuff (even more so in Leopard...), and extremely easy to integrate with Cocoa.

    Everything you've described is technically possible within a Quartz Composition, with no Cocoa required.

    The only tough part is the video input. You can use standard (VDIG) video inputs in a Quartz Composition, but HDV and AVCHD cameras don't have VDIG drivers. DV cameras obviously aren't HD, and anyway Apple's driver only supports one camera at once. Exactly what type of cameras were you planning to use?

    You could write something fairly simple in Cocoa to display video from HD network cameras, and then just overlay a Quartz Composition on top using QCView. In fact, if you like I can give you some code (from this screen saver) which will display video streamed from SecuritySpy.
     
  7. HiRez macrumors 603

    HiRez

    Joined:
    Jan 6, 2004
    Location:
    Western US
    #7
    Just a warning, Quartz Composer (the standalone application to build animations) and Quartz Compositor (the system windowing environment) are two different things. You can find some info on Quartz Composer here, including how to integrate a QCView with a Cocoa application.

    As a side question, does anyone have any info on what's new with QC in Leopard? Anything you can tell without breaking NDA? I haven't heard anything about it yet and I had to miss WWDC this year. I like the concept of Quartz Composer a lot, I just wish it had more flexibility and options (for instance, some more 3D primitives and the ability to import your own 3D geometry).
     
  8. Nutter macrumors 6502

    Joined:
    Mar 31, 2005
    Location:
    London, England
    #8
    All I'll say is that QC appears to be under very active development.

    PS. If you're in ADC select, check out ADC on iTunes for QC session videos from WWDC.
     
  9. Spookytooth macrumors newbie

    Joined:
    Nov 16, 2005
    Location:
    Los Angeles
    #9
    Quartz and Cocoa

    We use QC and Cocoa together, as do many these days, for controlling all sorts of graphics based apps. To implement video, there are some tricks to it. If the feeds are live, then a firewire source will be required in order to utilize the video patch in QC. Not sure if this will limit the number of cams you can have since it may be dependent upon what your cpu is. Mac mini has 1 firewire port. I would look into this before buying alot of gear. Have fun.

    Cheers,
    Spookytooth

    http://www.bsbtv.net
     

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