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Thread: can you save 8 bpp grayscale bitmaps?

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    Default can you save 8 bpp grayscale bitmaps?

    I know it's possible to save pixmaps like this:

    myPixmap.save("image.bmp", 0, -1);

    but the resulting file is 24 bpp rgb image.

    Is it also possible to make 8 bpp grayscale images this way?

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    Default Re: can you save 8 bpp grayscale bitmaps?

    I needed to get a 1 bpp grayscale the other day for OCR purposes, but I never could get Qt to do this

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    Default Re: can you save 8 bpp grayscale bitmaps?

    You will have to create an image plug-in that lets you do this: http://doc.trolltech.com/qq/qq17-imageio.html

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    Default Re: can you save 8 bpp grayscale bitmaps?

    I guess you could abuse QIcon to produce a grayscaled image:
    Qt Code:
    1. QIcon icon;
    2. QPixmap pixmap("test.png");
    3. icon.addPixmap(pixmap);
    4. QImage image = icon.pixmap(pixmap.size(), QIcon::Disabled).toImage();
    5. image = image.convertToFormat(QImage::Format_Indexed8);
    To copy to clipboard, switch view to plain text mode 
    J-P Nurmi

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