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Thread: Download image synchronously, check size and resize it in Qt.

  1. #1
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    Default Download image synchronously, check size and resize it in Qt.

    Hello. I'm new to qt. First of all sorry for my english.

    I want to download image from remote server synchronously.

    For this i need:
    1) Check size of image before downloading (Cancel downloading if size is bigger then some limit)
    2) Download SYNCHRONOUSLY (In my case I need this instead asynchronous)
    3) Sequre file (eg to prevent some bash script injections etc).
    4) Resize image to some default value (eg. reduce to some MaxWidth and MaxHeight or MaxKb if need) and convert to jpg (if file is png or something else).

    How can I do this with Qt way?
    I have read about QNetworkAccessManager and other classes, but I found only info about asynchronous download (using slots and signals).
    Thank you.

    P.S. I'm writing qt console application

  2. #2
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    Default Re: Download image synchronously, check size and resize it in Qt.

    Quote Originally Posted by moreo View Post
    1) Check size of image before downloading (Cancel downloading if size is bigger then some limit)
    Either by doing a head() call first or by deciding once you receive progress information.

    Quote Originally Posted by moreo View Post
    2) Download SYNCHRONOUSLY (In my case I need this instead asynchronous)
    You can always make an asynchronous operation synchronous, but why would you want to do that?

    Quote Originally Posted by moreo View Post
    3) Sequre file (eg to prevent some bash script injections etc).
    Whatever that means

    Quote Originally Posted by moreo View Post
    4) Resize image to some default value (eg. reduce to some MaxWidth and MaxHeight or MaxKb if need) and convert to jpg (if file is png or something else).
    QImage can do that.

    Cheers,
    _

  3. #3
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    Default Re: Download image synchronously, check size and resize it in Qt.

    Thanky you for replay.

    I need synchronous approach because of my application workflow (Yes, may be it would be better to rewrite but I have no time). It's a console application and operations should go step by step.

    Ok, I will try, thanks.

  4. #4
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    Default Re: Download image synchronously, check size and resize it in Qt.

    Quote Originally Posted by moreo View Post
    It's a console application and operations should go step by step.
    I don't see how it requires the process to be synchronous.
    Your biological and technological distinctiveness will be added to our own. Resistance is futile.

    Please ask Qt related questions on the forum and not using private messages or visitor messages.


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