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Tiny JPEG Decoder

docs/src/libs/image_support/tjpgd.rst

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.. _tjpgd:

================= Tiny JPEG Decoder

Tiny JPEG Decompressor is an LVGL interface to the TJpgDec library --- a generic JPEG image decompressor module that highly optimized for small embedded systems. It works with very low memory consumption, so that it can be incorporated into tiny microcontrollers, such as AVR, 8051, PIC, Z80, Cortex-M0, etc..

For a detailed introduction, see: TJpgDec <https://elm-chan.org/fsw/tjpgd/>__.

.. _tjpgd_overview:

Overview


Features and restrictions:

  • JPEG is decoded in 8x8 tiles.
  • Only baseline JPEG files are supported (no progressive JPEG support).
  • Read from file and C array are implemented.
  • Only the required portions of the JPEG images are decoded, therefore they cannot be zoomed or rotated.

.. _tjpgd_usage:

Usage


Set :c:macro:LV_USE_TJPGD to 1 in lv_conf.h. LVGL will register a new image decoder automatically so JPEG files can be used directly as image sources.

For example:

.. code-block:: c

lv_image_set_src(my_img, "S:path/to/picture.jpg");

.. note::

A file system driver needs to be registered to open images from files.  To do so,
follow the instructions in :ref:`file_system`.

Converter


Converting JPEG to C array

.. _tjpgd_example:

Example


.. include:: /examples/libs/tjpgd/index.rst

.. _tjpgd_api:

API


.. API startswith: lv_tjpgd_