Compressing Images to Share on the Internet
by Maureen Williams

There are times when you may have an image you've created, imported or scanned, which you would like to be able to share with others on the Internet.

If the image has been scanned or imported from a digital camera the size can be really large due to the resolution setting and results in a huge file size. This can cause problems for some people who have an old system or who are on a limited download per month with their ISP. Using PSP we can reduce the file size without compromising the overall quality of the image.

The resolution is determined by the dpi (dots per inch) of the image. The higher the dpi, the clearer the image will be. By the same token - the larger the file size.

Most digital cameras will use a setting referred to as mega-pixels or MP with an optimum setting of, say, 3.1 MP being designed to print out an image on paper of up to a size of 11" x 17". While this may be fine to print out, it is far too big to be able to view on a standard computer screen.

A resolution of 72 dpi is recommended for sharing and viewing images on the Internet.

 However, if you are sharing the image for the purpose of printing out the result,
 a higher resolution is desirable. A resolution of 300 dpi or more is best for printing.

In this short How-to we will investigate a couple of ways to reduce the file size.
I'm using PSP 7.04 but the same principal applies for Version 8 as well.

If you don't have Paint Shop Pro there is a program called Jpeg Resizer,
 which will resize multiple images with a few clicks of your mouse.

Step One
Open PSP and locate your image.

 Alternatively, scan the image you wish to work with using the
File, Import, TWAIN, Acquire to open your scanner.

Step Two
Click on Image, Resize

The Actual/print size box shows the physical size of the image and the resolution.
Change the Resolution to 72 - make sure the Maintain aspect ration box is checked.

Notes

In this same area you can also change the percentage of the original size,
by either reducing or enlarging the size. Keep in mind if you try to enlarge an image
 too much it will lose the clarity and tend to become "blocky" as the pixels are enlarged.

 It is better to start with a larger image and reduce the size rather than go the other way,
as the computer has to guess at the colours for the additional pixels and
 this results in the blocky appearance.

Step Three
At the top of this box you can also select a specific pixel size for the image.
 For most group requirements I would suggest using 350 pixels on the longest side
 as a reasonable setting. Enter this figure in either the width or height depending
 on whether your image is horizontal or vertical.

Step Four
Click on Effects, Sharpen, Sharpen.
In Ver 8 go to Adjust, Sharpen, Sharpen.

It is important to sharpen the image after you adjust the image size
 as this restores the clarity of the image.

Step Five
Saving the file after we have resized the image will result in a much smaller file size than before
 we resized it but we can reduce the size even further by using the JPEG Optimizer.
This tool can be activated by going to File, Export, JPEG Optimizer
or by clicking on the Options box from the File, Save As screen.
Make sure you have selected JPEG in the Save As type box.
Click on the Run Optimizer button at the bottom of the box.

Step Six
In the screen that opens you will notice the uncompressed file size on the left
 hand of the box and on the right hand side the compressed size.
In this example 583 kb uncompressed and 32 after it has been
compressed by a value of 21.

Although compressing an image can reduce the quality of the image some what it doesn't change the physical size of the image. You can adjust the quality of the image by moving the slider for the compression value. Left makes a larger file - clearer pic and right makes a smaller, not quite as clear pic. Adjust this setting depending on the image you are working with until you are happy with the result on the right hand side.

Click Ok and then save the file in the normal manner.

If you have any problems following this tutorial don't hesitate to contact me.