Is it possible to access the camera in a Macbook with REALbasic? I'd like to allow a user to capture an image from the camera.
Found 3 possible solutions:
a free plugin:
CamCapture
This should work for anyone needing an easy method to capture images from the built-in iSight camera. It should also work for other QuickTime capable camera sources. There is an example project but no documentation. FYI- the site and example is in French.
Commercial option, which I wasn't able to try is QTKit from MonkeyBread Software. This option is not free, but is documented and supported, unlike the free option.
realcapture is a free, unsupported RB canvas. It uses declares to access the camera.
Related
Modern webcams, like Logitech, often have features available through their proprietary software, that I don't see available in DirectShow, or in the interface that shows up, the one that's typically used to setup webcam parameters in software like VirtualDub or OBS.
For example, Logitech Brio has "HDR" and "FOV" switch, and Logitech C930 has an FOV switch also. I assume it must be somehow possible to access these without the proprietary software, right? Or is it ONLY accessible through Logitech's software and there is no way to set it from code otherwise?
I am working on a project where I need to capture video from two firewire cameras and do some processing on them. The one caveat is that I need to control the camera features (gain, gamma, white balance, etc).
After searching around I found two projects that seem to work. One is a cocoa project that interfaces with opencv but as far as I know, I can access the camera features through that code. The other is an openframeworks project that does allow me to access the features of the camera but doesn't currently interface with opencv.
I'm thinking about trying to combine the two projects and use the openframeworks one to set the camera features and the cocoa one to capture the images and do the processing. Is that a feasible idea or is there a better way to do this?
openFrameworks interfaces with openCv. There's an addon called ofxOpenCv and there are a couple of examples using it in openFrameworks/apps/addonsExamples
I have an old computer vision experiment that uses Video for Windows to grab frames from a camera connected to the PC. It's a hack, it uses VfW to create a preview window, then it does a GetDIBits from the window DC.
I'm finally ready to port this to DirectShow. My understanding was that I could grab frames from a video capture graph by using ISampleGrabber, but now I read that ISampleGrabber is deprecated.
What's the non-deprecated way to grab frames from a video feed? Do I have to implement my own DirectShow filter that does essentially what ISampleGrabber does?
DirectShow is not deprecated; just the DirectShow Editing Services. I would strongly recommend using DirectShow because of the much wider level of support, unless there are specific features of MF that are needed.
There's been no development of DES for some years, but the sample grabber is a widely-used filter that is somewhat independent of DES. I would be happy to recommend that you use it. If there is an issue in future versions of windows, it would not be more than a day or two's work to replace the filter.
G
I think Windows Media Foundation would be your best bet if you are only targeting Vista/Win7, otherwise you can still use DirectShow/SampleGrabber approach, I doubt it will be removed any time soon. Related question here.
I have this garden variety USB video camera, and it came with two mini-apps, one that just lets you see what the camera sees, and one that records to an .avi file.
But what's the API if I want to grab images from the camera in my own C program? I am making the assumptions that it's (1) possible and (2) desirable to make some call and have a 2D array of pixel information filled in.
What I really want to do is tinker with image processing algorithms, and for that I'd really like to get my code around some live data.
EDIT -
Having had a healthy exposure to Linux, I can grasp how (ideally/in theory) you could open() the device, use ioctl() to configure it, and read() the data. And I'm virtually certain that that's not how Windows is going to present the API. Not knowing what function names Windows might use for a video device API, or even if it has one, makes it difficult to look up, at least with the win32 api search capabilities that I have at my disposal.
You'll probably need the DirectShow API, provided that's how the camera operates. If the manufacturer created their own code path, you'll need their API.
Your first step, as pointed out by ChrisBD, is to check if Windows supports your device.
If that is the case you have three possible Windows APIs for capture:
DirectShow
VFW. Has more or less been replaced by DirectShow
MediaFoundation. Is the newest API that is intended to replace DirectShow. AFAIK not fully implemented yet and only available in Vista.
From the three DirectShow is the best choice. However, learning and using DirectShow is not a trivial task. An excellent example can be found here.
Another possibility is to use OpenCV. OpenCV is an image processing library, that you can also use for processing the images. OpenCV has an image capture API that provides a simpler abstraction and is easier to use than the Windows APIs.
The API is the way to go.
A good indication of whether the camera requires a bespoke one or not is to see if it is recognised by a PC without the manufacturer's applications installed. If windows has the drivers built in the you should be able to use the windows APIs to capture the images.
Alternatively if you know what compression codec has been used for the AVI file you could unpack it.
Ideally it would be good if you could capture the video in native (YUV, RGB15 or similar) format as then you can work on compression as well as manipulation.
I am creating object-detection program on Mac.
I want to use iSight in manual exposure mode to improve detection quality.
I tried iGlasses & QTKit Capture to do that and it worked but program runs very slowly and unstable.
So I want to try other solution.
In PhotoBooth.app, iSight seemed to be run in fixed exposure mode so there might be a way to do that.
I read QTKit Capture documents and OpenCV documents but I couldn't find the answer.
If you have any ideas, please tell me.
Thank you.
QTKit Capture, as easy as it is to use, lacks the ability to set manual camera parameters like gain, brightness, focus, etc. If you were using a Firewire camera, I'd suggest looking into the libdc1394 library, which gives you control over all these values and more if you're using an IIDC Firewire camera (like the old external iSight). I use this library for video capture from, and control of, CCD cameras on a robotics platform.
However, I'm guessing that you're interested in the internal iSight camera, which is USB. Wil Shipley briefly mentions control of parameters on internal USB iSights in his post "Frozen in Carbonite", but most of the Carbon code he lays out controls those values in IIDC Firewire cameras.
Unfortunately, according to this message in the QuickTime mailing list by Brad Ford, it sounds like you can't programmatically control anything but saturation and sharpness on builtin iSights through the exposed interfaces. He speculates that iGlasses is post-processing the image in software, which is something you could do using Core Image filters.
I finally managed to lock my iSight's autoexposure/autowhitebalance from my Cocoa App.
Check out www.paranoid-media.de/blog for more info.
Hmmm,
I tried & googled a lot these days but I couldn't find a good idea.
I think OpenCV + cocoa + iGlasses is the fastest one but still unstable.
If you have good idea, please reply.
Thank you.
The UVC Camera Control for Mac OSX by phoboslab uses basic USB commands and documented USB interfaces to access the webcam controls. The paranoid-media.de/blog listed above links to PhobosLab and provides a few additional tweaks to that method for the iSight. (Those tweaks can now also be found in the comments at phoboslab.