Windows XP Hacks [Electronic resources] نسخه متنی

Hack 86 Image Conversion in a Pinch

When you need to convert images from one format
to another, or need to shrink the size of existing images, try these
two graphics tools.

I
frequently have to convert graphics from one format to another. For
example, I may need to convert a high-quality, very large bitmap TIFF
file to a much smaller GIF or JPEG for posting to the Web. Sometimes,
I need to shrink the size of a file, while keeping the same
formatfor example, when sending a picture via email to
relatives or friends. When I'm creating my own icons
[Hack #19], I need to convert
graphics to the .ico format. There are also
times when I work with an artist who needs a file in a particular
format.

XP's built-in Paint program can't
really do the trick. It can convert only a handful of graphics
formats (for example, it can't handle
.pcx or .ico format), and
it won't let you customize the graphic; for example,
you can't alter the compression of
.jpg files to make them smaller. And it
can't do batch conversions; to convert a file you
have to open it and then save it in a different format.

For the kind of image conversion I do, I don't need
a full-blown graphics program like Photoshop that carries a
full-blown price tag of up to $600 (Photoshop Elements is another
alternative, but that's not free either). Instead, I
turn to the freeware and shareware programs detailed in the rest of
this hack.

10.2.1 IrfanView

For most image-conversion chores, I turn
to the free program IrfanView (http://www.irfanview.com), which is named
after its creator, Irfan Skiljan. It lets you convert individual
images or batches of images at a time, handles a wide variety of
formats, and gives you a great deal of control over the conversion.
For example, when converting to a JPEG, you can set the image
quality, whether to save as color or grayscale, and whether to save
it as a progressive
graphicone that gradually paints on the
screen as it downloads over the Web.

To do a batch conversion, after you run the
program, choose File Batch Conversion, browse to the
directory that has the files you want to convert, and select them.
Choose the output format and any options you want to apply to the
files. For example, for a certain project I needed to convert a group
of large graphics in TIFF format to JPEG format, and the resulting
files had to be very small, grayscale, and in progressive format.
Figure 10-1 shows the options I chose in IrfanView.

Figure 10-1. Converting a batch of files at a time with IrfanView

If you need to convert only an individual file, then call up the
file, save it in whatever format you want, and use options like those
shown in Figure 10-1.

IrfanView does much more than
image conversion. I use it as my all-purpose file viewer, for
example. It also works with scanners to bring images into your PC,
and it includes basic image-editing tools.

10.2.2 ImageConverter .EXE

One thing that IrfanView
can't do is display before-and-after pictures of the
graphic you're converting. For example, you
can't preview what the converted picture will look
like after it is converted. This can make image conversion a
hit-or-miss affair: you'll first have to choose your
conversion options, then convert the image, and then finally look at
the output. If you're not happy with the results,
you have to start back at the beginning, choose different options,
and hope this one works.

ImageConverter .EXE (http://www.stintercorp.com/genx/imageconverter.php)
shows you a side-by-side comparison of the before-and-after images,
before you do the actual conversion. It also shows you the size of
each image. That way, before you do the conversion, you can keep
tweaking it until you have the size and quality you want. Figure 10-2 shows an example of shrinking a JPEG file
while still trying to retain as much detail and quality as possible.
The image on the left is the original image and is 242 KB. The one on
the right is only 36 KB, but there is very little difference in the
quality of the two, so I chose to save this one.

Figure 10-2. A side-by-side comparison of image quality and size

The program does batch conversions, as well as letting you convert
files one at a time. It also lets you edit and add a wide variety of
special effects when you convert, such as changing the color depth
and contrast, adding a motion blur, posterizing the image, and more.
The program is shareware and free to try, but you're
expected to pay $35 if you decide to keep it.

10.2.3 See Also

Paint Shop Pro (http://www.paintshoppro.com) is an excellent
all-around graphics program that also does image conversion,
including batch image conversion. It's shareware and
free to try, but it has a registration fee of $99.