I have found the image processing toolbox for matlab, but all demos included in that toolbox expect the input to be avi videos. Does this toolbox work with webcams and/or simple images? If yes, could someone show me how?
For live video, or still images from a camera your tool of choice is the image acquisition toolbox. This, combined with the image processing toolbox you found, makes matlab quite the powerful video processing tool.
This small sample shows how to read image files into matlab matrices.
I know this probably isn't very helpful, but Mathworks likes to push Simulink as their tool of choice for streaming applications, including video processing.
http://www.mathworks.com/products/computer-vision/index.html
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I'm working on my academic project in which I've to record a video from the webcam.
In my google search, I've found that FFmpeg uses pipelining to record the video from the camera while OpenCV, AVbin use ctypes.
I don't know the pros and cons of either method, and wonder if you can help me decide which one to choose to write such kind of program in Linux.
I need to record 1024x768 30hz video and not experience latency/lag issues. Performance is the high priority.
Iam stuck with a project in which iam required to write a program in C++ that gets every frame of a raw .yuv video file and calculates the Signal to Noise ratio.
Iam stuck in this and can't find where to start from .. any guide to a tutorial or anything written on how to do this ? how to read a video and get the frames of the videos in c++?
Check out the ffmpeg libraries https://www.ffmpeg.org/about.html for extracting frames from a video stream.
There are other libraries, like OpenCV, which may also help with the image analysis part, and Windows-specific APIs.
For measuring signal:noise, you'll need a mathematical model for noise detection, like autocorrelation.
I am using the Bumblebee2 camera and I am having trouble with acquiring stereo images from it. When I attempt to access the camera using MATLAB, the program crashes.
Does anyone know how I can acquire the stereo images using FlyCapture?
Matlab cannot read the BumbleBee 2 output directly. To do that you'll have to record the stream and process it offline. I wrote a proprietary recorder based on the code samples in the SDK. You can split the left/right images and record each one in a separate video container (e.g. using OpenCV to write a compressed avi file). Later, you can load these images into memory, and use Triclops to compute disparity maps (or alternatively, use OpenCV to run other algorithms, like semi-global block matching).
Flycapture can capture image series or video clips, but you have less control over what you get. I suggest you use the code samples to write a simple recorder, and then load your output into Matlab in standard ways. Consult the Point Grey tech support.
I need to use DirectShow (C++) for recording a webcam and saving the data to a file.
I really don't know how DirectShow works, this is a "stage" (working experience), but at school we didn't study it.
I think the best way to implement this could be:
List the video devices connected to the computer
Select the correct camera (there will be only one)
Retrieve the video
Save it to a file
Now there are two problems:
Where can I find a good reference book or how do I start?
The saved video shouldn't be too big, does DirectShow provide a way to compress it?
I won't use OpenCV because sometime it doesn't work properly (It doesn't find the camera).
Are there any high level wrapper that could help?
EDIT: the program won't have a window, it will run in background called by a dll.
Where can I find a good reference book or how do I start?
DirectShow introduction material
The saved video shouldn't be too big, does DirectShow provide a way to compress it?
Yes it provides capabilities to attach codecs, that needs to be installed in the system. These are typically third party codecs (for reasons beyond the scope of brief answer). You might want to record into Windows Media files to not depend on third party codecs. SWee more on MSDN: Choosing a Compression Filter.
What should I use to perform screen capture on Windows for subsequent image processing?
I seek to do follow-up image processing in OpenCV.
Well the most straightforward thing to do is to use an off the shelf video capture tool to create an AVI file and then have image processing software operate on that, after the fact.
To get up and running:
CamStudio is free and open source and has a simple gui.
VirtualDub is also FOSS and is more powerful, but less intuitive to use. Its primarily a video editing and processing tool, but it actually has sophisiticated capture capabilities.
Both work on Windows and both can output uncompressed AVI files that OpenCV can read.
If you are completely new to OpenCV, then I recommend a O'Reilly's "Learning OpenCV". Its for the older OpenCV 1.1 but it will at least get you started.
If you crack open that book, and you find that its way above your head, then I would consider trying to do your image processing in a higher level language. MATLAB with the Image Processing Toolbox is well suited for rapid prototyping of image processing and its a much more forgiving development environment. Its an interpretative language, so you can see-as-you-code.
Based on the question as stated, this is as much info as I can provide. Perhaps consider providing more details about your specific application requirements?