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HTML screen capture quality

  • I've written a simple html screen capture based on the example in the Qt docs. It works very well except for varying image quality on different distributions when images in the html are re-sized.

    On Ubuntu 12.04 desktop and CentOS 6.3 no matter what re-sizing is done on images referenced from the html, the capture looks excellent. In the case of CentOS we're using Xvfb as it's headless.

    However, on Ubuntu 12.04 server (also using Xvfb), any significantly re-sized image referenced in the html comes out with jagged lines unless they are straight up or across. Qt5 is installed.

    The same html and images are used in every case.

    I tried phantomjs 1.9.8 on Ubuntu server and the captures come out with excellent quality, identical to desktop and CentOS. As far as I know phantomjs does not require a frame buffer (so it doesn't use Xvfb). This says to me that there is something with Xvfb specifically on Ubuntu server causing the poor image quality (since Xvfb on CentOS works just fine).

    Does anyone have any clue as to what might be going on?

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