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QImage::save(filename) bug on windows XP platfom

  • Hi,

    On big images 14592*14592 generated with my program written in the last version and different previous version of QT 4.7...
    the function QImage::save(filename) in RGB32 with a bmp format failed. On the same platform with the same image, QImage::save(filename) works with jpg format.

    I try the same code on linux32 and mac64 and the QImage::save function works with both formats
    I try too to open the windows genrated image on linux or mac and it's all black too. (the windows viewer is not reponsable)

    I compare the two bitmap (mac and Win) with ghex under ubuntu.
    File sizes (638,779,446 bytes) and bmp headers are similars but we can see that the image generated under windows is all black (NULL).

    Mac/Win/linux Image First Bytes (header) :
    42 4D 36 00 13 26 00 00 00 00 36 00 00 00 28 00 00 00 00 39 00 00 00 39 00 00 01 00 18 00 00 00 00 00 00 00 13 26 89 0B 00 00 89 0B 00 00 00 00 00 00 00 00 00 00

    After data are different:
    Win : 00 00 00 00 00 (all is null)....
    Mac : 53 62 4D 40 4F ....

    Best regards,

    Jean-Pierre Dumont

  • well i think the problem is the size...

    you would need about the same size of free ram on the machine as a single block of free ram as the file size is.

    How much ram does your windows machine have? Linux and Mac have way better ram management.

    but its just a guess.

  • thanks for answering ;-)

    my ubuntu say 3Go on my pc (linux and windows are on the same pc)
    I have try at home with a win seven 32bit with 4go, same problem...

  • I watch the code, the write is done line by line in the bmp handler, ie 14592*3 bytes at each time for this image isn't it ?
    It seem that the image is good in ram since the saving in jpeg format is working...

  • up ;-)

  • If you think this is a bug in Qt, could you please try to create a small but complete test case so that the devs can easily reproduce the issue, and then report the issue in the "Jira bugtracker":http://bugreports.qt.nokia.com?

  • ok, I create this issue



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