Pictures/images may have unwanted edges from scanning or too much background because the photographer was too far from the subject. This unwanted material not only makes the picture look bad it adds greatly to the file size. Where there is a restriction on maximum file size, such as posting on this message board, you don't want to resize the image smaller just so you can carry along this unwanted material. Let me give you some examples of file size reduction from trimming this waste. Trimming the image is called "Crop".

Let's say I scanned this image of the Montana forest fire.
 

After "Cropping" the unwanted edges I have
 

I didn't gain any on reducing the file size because what I trimmed was flat one color waste, but the image looks better.
 
 

Now what I really wanted to show people were the 2 deer in the stream. I cropped away the unwanted background for a better view of the deer and came up with an image.
 

Now I have some major file size reduction, but the image is pretty small.
 
 

Depending upon the image you may be able to resize it and make it larger. Resize in steps because as you go bigger the quality begins to degrade and get grainy, then it starts falling apart. The bad thing about resizing is you can go down in size, but not always up in size. Resizing instructions are in a separate section.
 

Bring the image up in IrfanView. Place the mouse cursor arrow a the imaginary corner of what you want to be the new image. Push down and hold the left mouse button. The arrow changes to a cross. Move the cross to the opposite imaginary corner of the new image forming a box around the new image. The box is the cut line with everything inside saved and everything outside getting thrown away. When you have a box about where you want it release the mouse button. Now if you are not happy with the box you drew, you can move the 4 sides  of the box in or out to capture exactly what you want in your new image.

To move the sides of the box, very slowly move the mouse cursor arrow across the line on the box. When the cursor arrow changes from 1 arrow head to 2, click and hold the left mouse button and drag the line to where you want it.
 

Click "Edit" on the "Menu Bar at the top of the screen. In the window that drops down click "Crop selection" and your new image will appear. If you don't like it click "Edit" again and then click "Undo" and it will take you back to start over. Be sure to save your new image with a jpg or gif filename extension.
 
 

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