Merge pull request #1 from crookedstorm/ppm

Ppm -- adding module

Author: crookedstorm

adafruit_imageload/pnm/ppm/__init__.py

@@ -0,0 +1,82 @@
+# The MIT License (MIT)
+#
+# Copyright (c) 2018 Scott Shawcroft for Adafruit Industries LLC
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+"""
+`adafruit_imageload.pnm.ppm`
+====================================================
+
+Load pixel values (indices or colors) into a bitmap and for a binary ppm,
+return None for pallet.
+
+* Author(s):  Matt Land, Brooke Storm, Sam McGahan
+
+"""
+
+__version__ = "0.0.0-auto.0"
+__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_ImageLoad.git"
+
+
+def load(file, magic_number, header, bitmap=None, palette=None):
+    """Load pixel values (indices or colors) into a bitmap and for a binary
+    ppm, return None for pallet."""
+    width = header[0]
+    height = header[1]
+    max_colors = (header[2] + 1) ** 3
+    bitmap = bitmap(width, height, max_colors)
+    palette = None
+
+    if bitmap:
+        minimum_color_depth = 1
+        while max_colors > 2 ** minimum_color_depth:
+            minimum_color_depth *= 2
+
+        line_size = width // (8 // max_colors)
+
+        if line_size % 4 != 0:
+            line_size += 4 - line_size % 4
+
+            if magic_number == b"P3":
+                # This is ascii
+                from . import ppm_ascii
+
+                return ppm_ascii.load(
+                    file,
+                    width,
+                    height,
+                    max_colors,
+                    bitmap=bitmap,
+                    palette=None,
+                )
+        chunk = bytearray(line_size)
+
+        for y in range(height - 1):
+            file.readinto(chunk)
+            pixels_per_byte = 8 // max_colors
+            offset = y * width
+
+            for x in range(width):
+                i = x // pixels_per_byte
+                pixel = (
+                    chunk[i] >> (8 - max_colors * (x % pixels_per_byte + 1))
+                ) & ((1 << minimum_color_depth) - 1)
+                bitmap[offset + x] = pixel
+
+    return bitmap, palette

adafruit_imageload/pnm/ppm/ppm_ascii.py

@@ -0,0 +1,57 @@
+# The MIT License (MIT)
+#
+# Copyright (c) 2018 Scott Shawcroft for Adafruit Industries LLC
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+"""
+`adafruit_imageload.pnm.ppm.ppm_ascii`
+====================================================
+
+Load pixel values (indices or colors) into a bitmap and for an ascii ppm,
+return None for pallet.
+
+* Author(s):  Matt Land, Brooke Storm, Sam McGahan
+
+"""
+
+__version__ = "0.0.0-auto.0"
+__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_ImageLoad.git"
+
+
+def load(file, width, height, max_colors, bitmap=None, palette=None):
+    """Load an ascii ppm into the Bitmap object"""
+    if bitmap:
+        for y in range(height - 1):
+            offset = y * width
+            for x in range(width):
+                triplet = bytearray()
+                color = bytearray()
+                while True:
+                    this_byte = file.read()
+                    if this_byte.isdigit():
+                        color += this_byte
+                    else:
+                        triplet += color
+                        color = bytearray()
+                        break
+
+                if len(triplet) == max_colors:
+                    bitmap[offset + x] = triplet
+
+    return bitmap, palette