bmp.md 1.5 KB
BMP decoder
This extension allows the use of BMP images in LVGL. This implementation uses bmp-decoder library. The pixels are read on demand (not the whole image is loaded) so using BMP images requires very little RAM.
If enabled in lv_conf.h by LV_USE_BMP LVGL will register a new image decoder automatically so BMP files can be directly used as image sources. For example:
lv_img_set_src(my_img, "S:path/to/picture.bmp");
Note that, a file system driver needs to registered to open images from files. Read more about it here or just enable one in lv_conf.h with LV_USE_FS_...
Limitations
- Only BMP files are supported and BMP images as C array (
lv_img_dsc_t) are not. It's because there is no practical differences between how the BMP files and LVGL's image format stores the image data. - BMP files can be loaded only from file. If you want to store them in flash it's better to convert them to C array with LVGL's image converter.
- The BMP files color format needs to match with
LV_COLOR_DEPTH. Use GIMP to save the image in the required format. Both RGB888 and ARGB888 works withLV_COLOR_DEPTH 32 - Palette is not supported.
- Because not the whole image is read in can not be zoomed or rotated.
Example
.. include:: ../../examples/libs/bmp/index.rst
API
.. doxygenfile:: lv_bmp.h
:project: lvgl