Graphics Conversion Libraries
Steve Fryatt (216) 2055 posts |
I’m after some suggestions… As part of a project I’m working on (an update to the documentation tools that I use for my software manuals), I’m looking for code that supports bitmap graphics conversion. I need to be able to convert between formats (JPEG, PNG, Sprite; others would be a bonus), and scale images down to a given size. I’m working in C, so that would be the language of choice. In addition, I would like the code to be able to be built for both Linux and RISC OS, to make it useful to as wide a range of people as possible. Sprite support is a must, and is generally the stumbling block. So far, I’ve drawn a blank. Before I go and reinvent the wheel, does anyone have any suggestions? Possible candidates need to be under a licence that would allow the end result to be made Open Source – most likely EUPL, unless another licence turns out to be more appropriate. |
Rick Murray (539) 13434 posts |
I think the usual answer on RISC OS is to point to ChangeFSI… If you happen to find anything |
nemo (145) 2437 posts |
Such a pity you’re not targeting RISC OS 4. :-/ |
Chris Johnson (125) 823 posts |
If you are interested in how DPScan and ConvImgs deals with this let me know and we can have an off-list discussion. The code licence is effectively 3 clause BSD. |
Steffen Huber (91) 1945 posts |
I thought that ImageMagick had support for RISC OS Sprites, but the docs say “no” https://www.imagemagick.org/script/formats.php – too bad, there is a C API and it is under Apache Licence. Although probably overkill for what you need. libvips https://github.com/jcupitt/libvips is also one of the usual recommendations, LGPL, but again no RISC OS Sprite support. Maybe PNG could be used as an “intermediate” format converting to/from sprites, but unfortunately Darren Salt’s Spr2Png is GPL. |
David Boddie (1934) 222 posts |
Reading the above, I was reminded that I needed to review the license on my sprite code because it was originally pretty vague. It turns out I already GPL’d it in 2005, so it was something that didn’t even need to go on the to-do list for a change! |
Steve Fryatt (216) 2055 posts |
It is… unfortunately, I won’t personally be running it on RISC OS. However, as a tool for generating RISC OS documentation, being able to build a native RISC OS tool from the code would make it a lot more useful to other people… :-)
I already use ImageMagick for a similar task elsewhere, but the lack of Sprite support (which is an issue for things like StrongHelp output) prompted me to look for other options.
I’m trying to avoid using intermediate formats, but it’s always an option. GPL isn’t a deal-breaker, although it’s not my first choice of licence.
I don’t follow? I’m targeting all versions of RISC OS (which rules out ROL’s image tools), but also need to be able to use the tool as part of a GCCDSK environment on a Linux box.
That sounds potentially interesting — thanks! |