Probably because the underlying GD Library doesn't have support for Windows .BMPs.

And that's probably because there is no existing open C library available for load/saving .BMPs as there are for .jpgs, .gifs etc.

And that maybe, though I haven't checked, because MS have never freely published the spcs for .BMPs?

Although my snippet works, for simple, uncompressed BMPs, the references I've seen suggest that 'the spec' has a multitude of extensions.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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In reply to Re^3: jpg to bmp in Windows by BrowserUk
in thread jpg to bmp in Windows by rochlin

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