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Old February 18th 18, 03:47 AM posted to rec.photo.digital,alt.comp.freeware,alt.windows7.general
Mayayana
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Posts: 1,514
Default Windows freeware to lock in a 3: or 4:3 aspect ratio for cropping

"JJ" wrote

| IMO, BMP should only be used when a software doesn't support a better
image
| format. How it stores 24bpp image pixels is unacceptably wasteful.

It depends on the situation. A BMP *is* the image.
You can compress it as a TIF if you don't want to use
the space, but the format is not wasteful. It's just
not compressed. It's what all other formats decompress
to. It's what gets displayed onscreen. It's the actual
image data of a raster image. Surely you knew that?

A BMP is *exactly* that. Aside from something like 22
bytes of header data, it's no more and no less than
the record of the color of each pixel in the image grid
of the image. It's what any graphic editor actually
works with. You open an image, it's converted
to a device independent bitmap, you edit it, then
it's saved out again as whatever. There's no such
thing as editing a TIF, GIF, PNG, JPG, etc. Those are
just storage methods with different pros and cons.
They're all storing a bitmap. (PNG and GIF can also
offer transparency, but it's still a bitmap that's stored.
The transparency is created by data that defines how
the image gets displayed.)

I suppose you could save as PNG, but neither TIF
nor PNG is remarkable compression. JPG only exists
because it has very good compression, it's royalty
free, and it's cross-platform. The quality is poor, but
it doesn't matter so much for web graphics and
photos of trivia sent between iPhones. It's not
a format for storing photos. Similarly with GIF: It's
handy for creating small files and it's cross-platform,
but it's lossy insofar as it reduces an image to 8-bit
color.

I sometimes save to TIF, but mostly I save as BMP
if I expect to work on an image. I have plenty of room
on disk. If ultred is going to print the images it may
not matter much. But if he's going to do further editing
there's no sense working in a lossy format just to save
space. That's why I designed for JPG and BMP -- One
for small-size images where quality isn't critical and
one for serious image editing.