Uwe, hua,
Many thanks for your comments.
Let me recapitulate and concentrate what I’ve found until now:
- Gimp, XnView , ACDSee and IrfanView are NOT able to store or export a GIF to BMP and keeping the transparent color (alpha channel).
- As you stated here:
viewtopic.php?f=17&t=13192,
after long searching and testing in the internet, i found a tool ( freeware ) to convert any PNG, ICO, GIF ... to BMP ( keeping the Alpha-Channel ).
you can use an icon editor to do the job.
- The representatives of this software category converts the GIF, PNG, or other formats at first to ICO and then in a second step to BMP with the possibility to store the transparency.
- Out of topic: If you are reading about this issue in dedicated forums, it becomes quite clear, that the BMP format is outdated, most of the people didn’t even know that BMP’s has the option to set an alpha channel
- Then tested IcoFX for single GIF’s and it works. Doesn’t know if batch converting is possible, the program hang up when browsing a folder.
- Also ‘nConvert’ can convert to ICO! So trying with ‘nconvert -transparent value -out ico *.gif’, but the transparent areas are only converted partly, it’s buggy at this point, so I’ve done no further tests.
- Then found ‘Axialis IconWorkshop’ and downloaded the 30 days trial. This program makes a very good impression. It has functions like ‘How to Batch Create Icons From Images, icons, Cursors...’ and ‘How to Batch Create PNG (BMP) images with Transparency from Icons...’
So, IconWorkshop exactly promises what I want and the first tests are successful