[Mono-aspnet-list] Improve image resizing quality

[Daniel Lo Nigro]

You could try GraphicsMagick - It's a fork of ImageMagick that has had some
tweaks done. Not sure if any of the tweaks relate to quality. I think
there's a whole bunch of options you can use that might help, too.

Glad to hear you got it working, though!


On Sat, Mar 16, 2013 at 9:29 PM, Patrick Epstein <Patrick.Epstein at gmx.de>wrote:

> Thank you both for your fast answers! I'm using now the technique
> described in your blog article and it works fine. :) My ImageMagick
> downsized jpeg images are still a tiny bit less sharp than GDI+ but
> filesize is also smaller like 30-40%. I'm happy with that for now! Image
> resizing seems to be a big topic anyways if I look at that ImageMagick
> documentation about that.
>
> Best regards
> Patrick
>
> 2013/3/16 Daniel Lo Nigro <lists at dan.cx>
>
>> Microsoft's .NET Framework uses GDI+ (which is a part of Windows) whereas
>> Mono uses libgdiplus <http://www.mono-project.com/Libgdiplus> which is a
>> wrapper around the Cairo graphics library <http://www.cairographics.org/>.
>> This is why you're seeing differences between the two.
>>
>> The link you posted uses the ImageMagick library, which is something I'd
>> recommend if you're not happy with the quality of the System.Drawing
>> output. ImageMagick (or GraphicsMagick, which is a fork of it) is what I
>> use with PHP and Node.js and it works pretty well. If you don't want to
>> mess around with P/Invoke and native libraries, you could just use
>> System.Diagnostics.Process to run ImageMagick. Just get it working
>> perfectly from the command-line, and then copy the command into your app :).
>>
>> See the ImageMagick docs: http://www.imagemagick.org/Usage/resize/#resize
>>
>>
>> On Sat, Mar 16, 2013 at 4:47 AM, Patrick Epstein <epstone2 at gmail.com>wrote:
>>
>>> Hello,
>>>
>>> I'm resizing images with the same c# code on windows and linux and the
>>> results on linux are worse. Just a bit less than acceptable.
>>> What should I do to get comparable good results?
>>>
>>> What I'm doing right now:
>>>
>>>  image.RotateFlip(System.Drawing.RotateFlipType.Rotate180FlipNone);
>>>  image.RotateFlip(System.Drawing.RotateFlipType.Rotate180FlipNone);
>>>
>>> var resized  =  resizedImage = image.GetThumbnailImage(width, height,
>>> null, IntPtr.Zero);
>>>
>>>  var encoderParameters = new EncoderParameters(1);
>>>  encoderParameters.Param[0] = new
>>> EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 90);
>>>
>>> saving...
>>>
>>> Or is this the way to go?
>>>
>>> http://www.toptensoftware.com/Articles/17/High-Quality-Image-Resampling-in-Mono-Linux
>>>
>>> Best regards,
>>> Patrick
>>>
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>>> Mono-aspnet-list mailing list
>>> Mono-aspnet-list at lists.ximian.com
>>> http://lists.ximian.com/mailman/listinfo/mono-aspnet-list
>>>
>>>
>>
>
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