Merge pull request #81 from ch4nsuk3/jpg-support

Added JPG support

Author: tannewt

adafruit_imageload/__init__.py

@@ -47,6 +47,7 @@ def load(
     palette is the desired palette type. The constructor should take the number of colors and
     support assignment to indices via [].
     """
+    # pylint: disable=too-many-branches
     if not bitmap or not palette:
         try:
             # use displayio if available
@@ -89,4 +90,8 @@ def load(
             from . import png
 
             return png.load(file, bitmap=bitmap, palette=palette)
+        if header.startswith(b"\xff\xd8"):
+            from . import jpg
+
+            return jpg.load(file, bitmap=bitmap)
         raise RuntimeError("Unsupported image format")

adafruit_imageload/jpg.py

@@ -0,0 +1,56 @@
+# SPDX-FileCopyrightText: 2024  Channing Ramos
+#
+# SPDX-License-Identifier: MIT
+
+"""
+`adafruit_imageload.jpg`
+====================================================
+
+Load a JPG into a bitmap by calling the jpegio class.
+
+* Author(s): Channing Ramos
+
+"""
+
+# A separate try for jpegio. Not every board supports it and this import may fail.
+# If that happens an ImportError with a proper message needs to be raised
+try:
+    from jpegio import JpegDecoder
+except ImportError:
+    print("jpegio not supported on this board.")
+
+try:
+    from io import BufferedReader
+    from typing import Tuple, Optional
+    from .displayio_types import BitmapConstructor
+except ImportError:
+    pass
+
+from displayio import Bitmap, ColorConverter, Colorspace
+
+__version__ = "0.0.0+auto.0"
+__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_ImageLoad.git"
+
+
+def load(
+    file: BufferedReader,
+    *,
+    bitmap: BitmapConstructor,
+) -> Tuple[Bitmap, Optional[ColorConverter]]:
+    """
+    Loads a JPG image from the open ''file''.
+    The JPG must be a Baseline JPG, Progressive and Lossless JPG formats are not supported.
+
+    Returns tuple of bitmap object and ColorConverter object.
+
+    :param io.BufferedReader file: Open file handle or compatible (like 'io.BytesIO')
+    :param object bitmap: Type to store bitmap data.
+     Must have API similar to 'displayio.Bitmap'. Will be skipped if None.
+     Will be skipped if None.
+    """
+    decoder = JpegDecoder()
+    width, height = decoder.open(file)
+    bitmap_obj = bitmap(width, height, 65535)
+    decoder.decode(bitmap_obj)
+
+    return bitmap_obj, ColorConverter(input_colorspace=Colorspace.RGB565_SWAPPED)

examples/imageload_jpg_simpletest.py

@@ -0,0 +1,22 @@
+# SPDX-FileCopyrightText: 2024  Channing Ramos
+#
+# SPDX-License-Identifier: MIT
+
+"""
+Basic JPG imageload example
+"""
+
+import board
+import displayio
+import adafruit_imageload
+
+group = displayio.Group()
+board.DISPLAY.root_group = group
+
+image, color_converter = adafruit_imageload.load("images/jpg_test.jpg")
+
+tile_grid = displayio.TileGrid(image, pixel_shader=color_converter)
+group.append(tile_grid)
+
+while True:
+    pass

examples/images/jpg_test.jpg

@@ -0,0 +1,2 @@
+# SPDX-FileCopyrightText: 2024 Channing Ramos
+# SPDX-License-Identifier: MIT