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QT mobility API : How to record video

  • Hi,

    the task of my project would be to record a video and analize the frames for

    image processing.

    Please, is there any sample project to record on a buffer and not on a file

    and is there any class to analize the sequences of frame?

    I have already searched in forum but seems nobody has posted any similar question

    Thanks in advance, regards

  • Not sure there exists a (high level) API to record to memory (partly because of the limited memory on mobile/embedded devices). What you could do is did into the mobility sources and see how the recording is done and if there is someway you could hook into the process (or copy a private class and use it in your project). However, I would suggest you re-think whether you actually want the recording to be done to memory.

  • I saw in the mobility API it can record on file. Let's see the second part of problem, is it possible to read the file to analize frame by frame instead of playing?
    Is there a class that allows this?

  • What exactly do you want to do?

    What kind of analysis do you want to do?

    What is the input format for that analysis?

  • I would like to xor the frame with the previous frame and detect if there is a variance, the total number of 1s is above one threshold that i set up.
    i imagine to convert the frame in bitmap or similar...

  • One way would be to subclass "QAbstractVideoSurface":http://doc.qt.nokia.com/qtmobility-1.2/qabstractvideosurface.html and use QMediaPlayer. Otherwise, again, look into the Qt mobility sources. It's quite useful in finding what you need.

  • Thanks, I will.


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