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+# JPG decoder
+
+Allow the use of JPG images in LVGL. Besides that it also allows the use of a custom format, called Split JPG (SJPG), which can be decoded in more optimal way on embedded systems.
+
+## Overview
+  - Supports both normal JPG and the custom SJPG formats.
+  - Decoding normal JPG consumes RAM with the size fo the whole uncompressed image (recommended only for devices with more RAM)
+  - SJPG is a custom format based on "normal" JPG and specially made for LVGL.
+  - SJPG is 'split-jpeg' which is a bundle of small jpeg fragments with an sjpg header.
+  - SJPG size will be almost comparable to the jpg file or might be a slightly larger.
+  - File read from file and c-array are implemented.
+  - SJPEG frame fragment cache enables fast fetching of lines if available in cache.
+  - By default the sjpg image cache will be image width * 2 * 16 bytes (can be modified)
+  - Currently only 16 bit image format is supported (TODO)
+  - Only the required partion of the JPG and SJPG images are decoded, therefore they can't be zoomed or rotated.
+
+## Usage
+
+If enabled in `lv_conf.h` by `LV_USE_SJPG` LVGL will register a new image decoder automatically so JPG and SJPG files can be directly used as image sources. For example:
+```
+lv_img_set_src(my_img, "S:path/to/picture.jpg");
+```
+
+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_...`
+
+
+
+## Converter
+
+### Converting JPG to C array
+  - Use lvgl online tool https://lvgl.io/tools/imageconverter
+  - Color format = RAW, output format = C Array
+
+### Converting JPG to SJPG
+python3 and the PIL library required. (PIL can be installed with `pip3 install pillow`)
+
+To create SJPG from JPG:
+- Copy the image to convert into `lvgl/scripts`
+- `cd lvgl/scripts`
+- `python3 jpg_to_sjpg.py image_to_convert.jpg`. It creates both a C files and an SJPG image.
+
+The expected result is:
+```sh
+Conversion started...
+
+Input:
+        image_to_convert.jpg
+        RES = 640 x 480
+
+Output:
+        Time taken = 1.66 sec
+        bin size = 77.1 KB
+        walpaper.sjpg           (bin file)
+        walpaper.c              (c array)
+
+All good!
+```
+
+
+## Example
+```eval_rst
+
+.. include:: ../../examples/libs/sjpg/index.rst
+
+```
+
+## API
+
+```eval_rst
+
+.. doxygenfile:: lv_sjpg.h
+  :project: lvgl