1/*
2Notice how I am manipulating the RGB values of each pixel, this is the power of these classes. The Drawing classes have the
3pixel drawing capabilities to draw lines and such already written for you, but handling a grayscale byte for byte is faster
4than relying on their other classes. I also chose to load and encode as PNG, but they have loaders and encoders for other
5file types as well that work the same way.
6*/
7
8using System;
9using System.IO;
10using System.Windows.Media.Imaging;
11using System.Windows.Media;
12
13namespace MyNamespace.Imaging
14{
15 public sealed partial class MyImageClass
16 {
17 public enum eBpp : byte { _1 = 0, _8 = 1, _16 = 2, _24 = 3, _32 = 4, _40 = 5, _48 = 6, _56 = 7, _64 = 8, _128 = 16 }
18
19 public static BitmapSource LoadPng(string fileName)
20 {
21 FileStream fs = File.OpenRead(fileName);
22 byte[] data = new byte[fs.Length];
23 fs.Read(data, 0, (int)fs.Length);
24 fs.Close();
25 MemoryStream ms = new MemoryStream(data);
26 PngBitmapDecoder decoder = new PngBitmapDecoder(ms, BitmapCreateOptions.None, BitmapCacheOption.None);
27 return decoder.Frames[0];
28 }
29
30 public static void MakeGrayScale(ref BitmapSource image)
31 {
32 byte bytes = (byte)(eBpp)Enum.Parse(typeof(eBpp), "_" + image.Format.BitsPerPixel);
33 int stride = image.PixelWidth * bytes;
34 long size = image.PixelHeight * stride;
35 byte[] source = new byte[size];
36 image.CopyPixels(source, stride, 0);
37 byte[] dest = new byte[size];
38 if (image.Format.BitsPerPixel == 32)
39 {
40 for (int i = bytes - 1; i < size; i += bytes)
41 {
42 uint avrg = (uint)source[i - 3] + (uint)source[i - 2] + (uint)source[i - 1];
43 if (avrg != 0)
44 avrg = avrg / 3;
45
46 dest[i - 3] = (byte)avrg;
47 dest[i - 2] = (byte)avrg;
48 dest[i - 1] = (byte)avrg;
49 dest[i] = source[i]; //alpha
50 }
51 } //aren't handling any other types than 32bit color, but these can be added easily
52
53 image = BitmapSource.Create(image.PixelWidth, image.PixelHeight, 96, 96, image.Format, BitmapPalettes.Halftone256Transparent, dest, stride);
54 }
55
56 public static MemoryStream PngEncode(BitmapSource image)
57 {
58 //encode image as png
59 PngBitmapEncoder encoder = new PngBitmapEncoder();
60 encoder.Interlace = PngInterlaceOption.On;
61 encoder.Frames.Add(BitmapFrame.Create(image));
62 MemoryStream ret = new MemoryStream(); //create valid return stream
63 encoder.Save(ret);
64 ret.Position = 0;
65 return ret;
66 }
67 }
68}