How do I create backdrop .bmp using 'convert' under linux?

[Myrmornis]

Hi there, I'm working in linux, trying to use the ImageMagick 'convert' utility. Could someone give me a 'convert' command to transform a jpeg into a .bmp suitable for use as a backdrop on a 5.5th gen ipod video?

The rockbox manual tells me that the bmp must be
"320x240x16 with the last number giving the colour depth in bits"

The simplest thing I've tried is

Code: [Select]

convert -thumbnail 320x240 arachnid.jpg arachnid.bmp

but this fails to load as a backdrop, and is not the same size file as backdrops I know to work. The backdrop images that function correctly are all of size 226K, whereas the above line produces a 202K image.

Thanks a lot,

Dan

[linuxstb]

Try:

Code: [Select]

convert -thumbnail 320x240\! arachnid.jpg arachnid.bmp

Without the ! at the end, convert will attempt to keep the aspect ratio of the image, and will only create a file that is close to 320x240, not exactly 320x240.

You can check the size of the resulting bmp file using "display arachnid.bmp" and then looking at the image properties.

[Myrmornis]

Cheers, that does it!

Dan