Reducing the Size of an Image File

About Resolution and Compression

It may be necessary to reduce the size of an image file before you submit your report. You can use the software that you used to create the image. If it was a digital camera or scanner, you can use the software that came with the camera or scanner. Most cameras and scanners save files in jpeg format; the file  name ends with ".jpg." There are two ways to reduce the file size of a jpeg file; I suggest using both ways. The first way is to reduce the resolution (the number of dots per inch). This will make a smaller picture so be careful not to make it too small. I suggest reducing the resolution to something less than 640 (width) or 480 (height). The second thing that you can do is to increase the compression. This reduces the number of bits used to store the file but does not the number of dots per inch. I suggest changing the jpeg compression to 0.75 or less. A smaller number means more compression and a smaller file size. It also means less image quality, so be careful not to overdo it.

Digital cameras normally come with photo editing software. If you don't have a digital camera, you can download one of the many free software packages for photo editing such as photoshop. Do a Google search for photoshop, then download and install it. Use the software's help feature to learn how to reduce the resolution and/or increase jpeg compression when saving.

Using Paint

If photo editing software is not available on your computer, you can use Windows Paint to reduce the size of the picture. It is available on all computers running any version of Windows. In Windows XP Click Start, then Programs, Accessories, Paint.

Open the image.

Paint automatically saves images that are compressed a moderate amount; it may not be necessary to do anything other than saving the file. Unfortunately, the program does not allow you to increase the compression; it has only one preset amount of compression.

You can use Paint to reduce the size of the picture. From the image menu, click Stretch/Skew. In the upper half of the dialog box, change the value of 100 in Horizontal and Vertical to to something smaller. For example change them both to 50 make a picture that is half as large. Be sure to change both horizontal and vertical the same amount.

Paint is a minimal program and it doesn't do much. You will probably have better luck using any other software. Most of the free programs are better than Paint but Paint does do some basic things and it may work for your needs.

 
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