WARNING: This blog entry was imported from my old blog on blogs.sun.com (which used different blogging software), so formatting and links may not be correct.
I get screenshots every now and then in the mail, and frequently in bad formats, so perhaps the following is not known to all:
- Do NOT send BMP files! They are uncompressed. A simple screenshot, which should be a something like a 50k gif, will be a 5 megabyte attachment - 100 times larger than necessary! Unfortunately, BMP is what you get by default when you grab screenshots with Ctrl-Printscreen
in Windows and paste it from the clipboard. TIFF, common on the Mac, suffers from a similar bloated file size problem since it too typically
is not compressed. - Do NOT use JPEG for screenshots! Unless all compression is turned off (which it never seems to be), JPEG is a spectacularly
bad format for uniform color surfaces like those you get from application screenshots. JPEG is great for photos - much better than GIF or PNG.
But for screenshots it introduces all kinds of ugly visual artifacts.
...and finally, a related issue: If you're going to show a scaled down version of a picture in a web page (e.g. a thumbnail),
don't just use the width and height attributes on the image tag! Not only does that require the full image to be downloaded anyway,
but worse yet, most browsers do a horrible job scaling pictures. Prescale the picture in an image editor instead.
On windows, I am using a nice free tool, Gadwin Printscreen. It permits to choose the format (bmp, jpg, gif, png, tif, tga), to resize the capture, ...
ReplyDeleteA very nice tool.
Just as an FYI ... the new Mac OS X release (Tiger) saves screenshots as PNG files, which is pretty useful. :-)
ReplyDeleteRegarding PNG on Tiger: I'm running Tiger on this laptop, and I don't see that. When I use the Snapshot application to grab a screenshot, and invoke Save, I get a filename dialog without a toggle to choose any other formats, and when I look at the file saved it's a .tiff.
ReplyDelete