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Thread: QImageReader and High Resolution pictures

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    Question QImageReader and High Resolution pictures

    I have about 2Gb National Geographics Maps http://www.google.com/search?q=National+Geographic+Maps
    with high resoulution. I want create scroller with QGraphicsScene/paintEvent and i don't wan't to load whole image to memory. How i can read images like a QTextStream pixel by pixel from HDD without knowing a format file? We need a streaming for pixels.

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    Default Re: QImageReader and High Resolution pictures

    You'd have to create your own image format plugin. You can then read the data frame by frame.
    Your biological and technological distinctiveness will be added to our own. Resistance is futile.

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    Default Re: QImageReader and High Resolution pictures

    But for this i must know picture format (BMP, JPEG, PNG, TIFF etc) or i can use Qt features for this?

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    Default Re: QImageReader and High Resolution pictures

    Yes, you have to know the image format. If you're able to tell where an image starts or ends, you can use a different approach - use QImage::loadFromData() and point it to the data containing a single image (header included).
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    Default Re: QImageReader and High Resolution pictures

    Quote Originally Posted by wysota View Post
    If you're able to tell where an image starts or ends, you can use a different approach - use QImage::loadFromData() and point it to the data containing a single image (header included).
    I can set only size, there is no start or end parameters. May be i can generate buffer with header and partial data, but diffirent formats have diffirent size of header and header itself.

    I try to compile ImageMagick with MinGW, but program crashed with exceptions inside IM dll.

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    Default Re: QImageReader and High Resolution pictures

    I'm not sure in what way would ImageMagick be helpful to you.
    Your biological and technological distinctiveness will be added to our own. Resistance is futile.

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