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lvgl_v8_back/lvgl/docs/libs/bmp.md

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+# BMP decoder
+
+This extension allows the use of BMP images in LVGL.
+This implementation uses [bmp-decoder](https://github.com/caj-johnson/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](https://docs.lvgl.io/master/overview/file-system.html) 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](https://lvgl.io/tools/imageconverter).
+- 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 with `LV_COLOR_DEPTH 32`
+- Palette is not supported.
+- Because not the whole image is read in can not be zoomed or rotated.
+
+
+## Example
+```eval_rst
+
+.. include:: ../../examples/libs/bmp/index.rst
+
+```
+
+## API
+
+```eval_rst
+
+.. doxygenfile:: lv_bmp.h
+  :project: lvgl
+
+```