1  # The MIT License (MIT)
 2  #
 3  # Copyright (c) 2018 Scott Shawcroft for Adafruit Industries LLC
 4  #
 5  # Permission is hereby granted, free of charge, to any person obtaining a copy
 6  # of this software and associated documentation files (the "Software"), to deal
 7  # in the Software without restriction, including without limitation the rights
 8  # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 9  # copies of the Software, and to permit persons to whom the Software is
10  # furnished to do so, subject to the following conditions:
11  #
12  # The above copyright notice and this permission notice shall be included in
13  # all copies or substantial portions of the Software.
14  #
15  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18  # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20  # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
21  # THE SOFTWARE.
22  """
23  `adafruit_imageload.pnm.pgm`
24  ====================================================
25  
26  Load pixel values (indices or colors) into a bitmap and colors into a palette.
27  
28  * Author(s): Matt Land, Brooke Storm, Sam McGahan
29  
30  """
31  # pylint: disable=import-outside-toplevel
32  
33  
34  def load(file, magic_number, header, *, bitmap=None, palette=None):
35      """
36      Perform the load of Netpbm greyscale images (P2, P5)
37      """
38      if header[2] > 256:
39          raise NotImplementedError("16 bit files are not supported")
40      width = header[0]
41      height = header[1]
42  
43      if magic_number == b"P2":  # To handle ascii PGM files.
44          from . import ascii as pgm_ascii
45  
46          return pgm_ascii.load(file, width, height, bitmap=bitmap, palette=palette)
47  
48      if magic_number == b"P5":  # To handle binary PGM files.
49          from . import binary
50  
51          return binary.load(file, width, height, bitmap=bitmap, palette=palette)
52  
53      raise NotImplementedError("Was not able to send image")