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libraries/lvgl/docs/libs/png.md

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+# PNG decoder
+
+Allow the use of PNG images in LVGL. This implementation uses [lodepng](https://github.com/lvandeve/lodepng) library.
+
+If enabled in `lv_conf.h` by `LV_USE_PNG` LVGL will register a new image decoder automatically so PNG files can be directly used as any other image  sources.
+
+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_...`
+
+The whole PNG image is decoded so during decoding RAM equals to `image width x image height x 4` bytes are required.
+
+As it might take significant time to decode PNG images LVGL's [images caching](https://docs.lvgl.io/master/overview/image.html#image-caching) feature can be useful.
+
+## Example
+```eval_rst
+
+.. include:: ../../examples/libs/png/index.rst
+
+```
+
+## API
+
+```eval_rst
+
+.. doxygenfile:: lv_png.h
+  :project: lvgl
+