Uncompressed Image Format With Transparency?

[TC]

Is there any way to save a bitmap in an uncompressed format which preserves
transparency?

The BMP format is uncompressed, but doesn't support transparency. The GIF
format has an alpha channel, but always uses compression. The TIFF format
preserves transparency and has an option for no compression, but that option
doesn't seem to be supported by VB.NET. I'm intrigued by the image format
called MemoryBMP; I'd like to test it out, but every time I save an image in
that format, I get the error "Value cannot be null."

Any suggestions?

I want an uncompressed format, by the way, because I want all images of the
same dimensions to have exactly the same file size. (I know it isn't that
simple, but please humor me.)
-TC

[Robin Tucker]

A direct draw surface (.dds?).

"TC" <v@x.z> wrote in message news:WiUqc.33537$bS1.17532@okepread02...

Is there any way to save a bitmap in an uncompressed format which preserves transparency?

The BMP format is uncompressed, but doesn't support transparency. The GIF
format has an alpha channel, but always uses compression. The TIFF format
preserves transparency and has an option for no compression, but that option doesn't seem to be supported by VB.NET. I'm intrigued by the image format
called MemoryBMP; I'd like to test it out, but every time I save an image in that format, I get the error "Value cannot be null."

Any suggestions?

I want an uncompressed format, by the way, because I want all images of the same dimensions to have exactly the same file size. (I know it isn't that
simple, but please humor me.)
-TC

[Herfried K. Wagner [MVP]]

* "TC" <v@x.z> scripsit:

Is there any way to save a bitmap in an uncompressed format which preserves
transparency?

PNG supports transparency, maybe you can adjust "compression" to fit
your needs.

--
Herfried K. Wagner [MVP]
<URL:http://dotnet.mvps.org/>