Tutorial - Image Editing with IrfanView
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Image FeaturesIrfanView's Image menu (at right) contains features for rotating an image, resizing it, reducing the color count, enhancing colors, sharpening, and applying a few special effect. We will change the brightness and contract of our image, reduce to a size appropriate for the web, and finally sharpen. Some designers capture or scan an image at a very high resolution, then reduce and sharpening it several times to prepare it for the web.
First let's apply Enhance colors of our image. For example we want to bring out the blue sweater color. From the Image menu select Enhance colors. This brings up a dialog box to adjust the Balance, Brightness, Contrast, and Gamma Correction.
A rule of thumb is that the color parameters should be changed only a little at a time. Observe whether the image has improving or not. Then either continue making changes or go back. In the example the Brightness and Contrast are set to 10 and the Gamma correction is set to 1.75. The thumbnail shows the image with these values applied. When it has the "right look" click Apply to original image or OK.
Resize an image. After cropping the image was still 539x775, an aspect ratio of 0.675 (=539/775) or about two-thirds. So how large do we want the final image? 200x300? 160x240? This has to be determined by how the image is to be used. Let's say we want the height to be 240 px. From the Image menu select Resize/Resample.This brings up the resize dialog box.
The image can be resized by either choosing a percentage of the original or entering the new size. To prevent distortions (unless that is what you want) make sure the Preserve aspect ratio box is checked. Enter 240 for the new height; the width is automatically calculated as 167 because the Preserve aspect ratio box is checked. When the new size is set click OK to apply it to the image. If you change your mind, Edit > Undo will reset the image to the previous size.
Okay, the size is fixed. Now let's Sharpen the image to improve the edges. To determine how much sharpening will be done select Image > Effects > Setup. This brings up a dialog box with parameters for the various effects. 50 is the default value for Sharpen. Okay, let's try that. Close the Parameters box by clicking OK or Cancel. Now select Image > Sharpen. It doesn't look like there was a change. Go back to Image > Effects > Setup and change the Sharpen value to 75. Click OK and now select Image > Sharpen. Ah, the image is sharpened.
Well, we're done. Let's Save as a jpg image.Here is what the final product looks like. It's size is 43.5 K.B
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