save - c#: reduced image quality when saving JPEG at 100% quality -

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i'm loading jpeg image , saving without manipulation it. image quality noticeably reducing.

here code:

bitmap imgoutput = new bitmap(@"d:\image.jpg"); graphics outputgraphics = graphics.fromimage(imgoutput);        encoderparameters myencoderparameters = new encoderparameters(3); myencoderparameters.param[0] = new encoderparameter(system.drawing.imaging.encoder.quality, 100l); myencoderparameters.param[1] = new encoderparameter(system.drawing.imaging.encoder.scanmethod, (int)encodervalue.scanmethodinterlaced); myencoderparameters.param[2] = new encoderparameter(system.drawing.imaging.encoder.rendermethod, (int)encodervalue.renderprogressive);  imagecodecinfo[] codecs = imagecodecinfo.getimageencoders(); imagecodecinfo ici = null; foreach (imagecodecinfo codec in codecs) {     if (codec.mimetype == "image/jpeg")         ici = codec; }  imgoutput.save(@"d:\result.jpg", ici, myencoderparameters);

and get: http://i.imgur.com/5bg1tpm.jpg zoom: http://i.imgur.com/vdx8sl5.jpg

is there image quality settings?

jpeg, being lossy format introduces loss on every save. particularly bad @ compressing sharp edges. according this msdn article, you're setting image quality correctly. can play other settings if want try , optimize image quality, don't know how came scanmethod , rendermethod. however, best way in opinion use lossless format (png, tiff, etc).

update

it appears due bad gdi+ jpeg encoder. more on on the msdn forums. conclusion - use third party imaging library, there plenty free ones out there.


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