Module: DNN::ImageIO

Defined in:
lib/dnn/lib/image_io.rb

Defined Under Namespace

Classes: Error, ReadError, WriteError

Class Method Summary collapse

Class Method Details

.read(file_name) ⇒ Object

Raises:



6
7
8
9
10
11
 
# File 'lib/dnn/lib/image_io.rb', line 6

def self.read(file_name)
  raise ImageIO::ReadError.new("#{file_name} is not found.") unless File.exist?(file_name)
  bin, w, h, n = Stb.stbi_load(file_name, 3)
  img = Numo::UInt8.from_binary(bin)
  img.reshape(h, w, 3)
end

.write(file_name, img, quality: 100) ⇒ Object 



13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
 
# File 'lib/dnn/lib/image_io.rb', line 13

def self.write(file_name, img, quality: 100)
  if img.shape.length == 2
    img = Numo::UInt8[img, img, img].transpose(1, 2, 0).clone
  elsif img.shape[2] == 1
    img = img.shape(img.shape[0], img.shape[1])
    img = Numo::UInt8[img, img, img].transpose(1, 2, 0).clone
  end
  h, w, ch = img.shape
  bin = img.to_binary
  case file_name
  when /\.png$/i
    stride_in_bytes = w * ch
    Stb.stbi_write_png(file_name, w, h, ch, bin, stride_in_bytes)
  when /\.bmp$/i
    Stb.stbi_write_bmp(file_name, w, h, ch, bin)
  when /\.jpg$/i, /\.jpeg/i
    Stb.stbi_write_jpg(file_name, w, h, ch, bin, quality)
  end
rescue => ex
  raise ImageIO::WriteError.new(ex.message)
end