Down sizing the quality of pictures
for the web
| Topic: Down
sizing the quality of pictures for the web |
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Our final
step is to save our picture as a new file name on the hard disk, and
in the process, down sizing it's quality sufficiently to reduce the
byte count of the photograph without diminishing the quality
significantly. First look at the two photographs at the top. The one
on the left is the original and is 94,089 bytes in size. The one on
the right is the saved, down sized copy and is 15,851 bytes in size.
If your image is black and white or contains very few colors,
consider saving it as a GIF file rather than as a JPG file.
Otherwise, find the "Save As", "Save for Web",
or other like function in your picture editing software and start to
save the picture as some file name other than the one you are
editing. When you do this, you will see some kind of dialog box like
the one shown below.
 This
function allows you set the quality from very high to very
low. Note that we have selected medium in this example.
Medium will generally allow the picture to be saved many times
smaller ( in byte size, not physical size) without changing how it
looks on your web page. Try different settings on different save's
of your file and then examine the size of the file and bytes and how
it looks to you. You will quickly get the idea. Note that we have
also set the image to Progressive with the maximum number of scans.
What this does is allow the picture to display on a web page very
fast but in very poor quality. But then is displays again, with the
quality improved. With 5 scans, this process is repeated 5 times.
This allows the user to see the picture coming - sort of like a
dissolve-in effect.
Your photo editing program may have a different looking interface
dialog for saving jpg images from the one shown here. Practice using
it to save jpg images with lower and lower quality until the image
still looks good but has the smallest size possible. Look carefully
at this dialog box and you will see a slight distortion around the
bold words starting with "Baseline ("Standard"). This
image could have been saved with a slightly higher quality setting
to eliminate that distortion.
This is all we did to reduce the byte count size of the two
pictures at the top of the page from 94,089 bytes to 15,851 bytes.
Remember where we started. We what to get a picture that is huge and
one that can take minutes to load on a web page down to a size where
it will lode in something near 1 second.
We cannot tell you where in your particular software this feature
exists but all picture editing software that allows you to save an
image as a JPG (usually you will see this format called JPEG ) has
this feature. Just be sure to save the original file you are working
on as a different file name.
This is the end of this tutorial. You may press Here
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