C＃将图像转换为完整的黑白

问题描述

| 我的gif图片太大了，无法满足我的需要（即使是100〜300kb） 在photoshop中，我仅通过将他使用的颜色数减少为2（黑白）就设法将160kb gif转换为15kb（大小的1/10！）。 我想在应用程序中做同样的事情，但是我所能找到的就是将图像变成灰度，这将我的160kb gif变成了100kb。 无论如何，有没有将我的gif变成黑白的？可以将gif缩小到更小的尺寸的任何其他方式将受到赞赏。     

解决方法

        这是一个代码项目示例，说明如何将其转换为G4压缩的TIFF。请注意，这对于具有大量空白和文本的图像非常有用，但对图像却不太好。对于图像，您可能希望查看其他答案并使用抖动。     ,        在SO上有一些代码：我认为应该进行拜耳有序抖动处理（未经测试）。值得一试。     ,        您可以为此使用ImageMagick。通过ѭ0by通过命令行运行它，或使用Windows安装过程中的COM接口。选项“-单色”是您的朋友。     ,        在C＃中将图像转换为黑白

/*
Copyright (c) 2010 <a href=\"http://www.gutgames.com\">James Craig</a>

 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.*/

#region Usings
using System.Drawing;
using System.Drawing.Imaging;
#endregion

 namespace Utilities.Media.Image
 {
    /// <summary>
    /// Helper class for setting up and applying a color matrix
     /// </summary>
     public class ColorMatrix
    {
         #region Constructor

        /// <summary>
        /// Constructor
         /// </summary>
         public ColorMatrix()
         {
       }

         #endregion

           #region Properties

         /// <summary>
         /// Matrix containing the values of the ColorMatrix
         /// </summary>
         public float[][] Matrix { get; set; }

         #endregion

         #region Public Functions

         /// <summary>
         /// Applies the color matrix
         /// </summary>
         /// <param name=\"OriginalImage\">Image sent in</param>
         /// <returns>An image with the color matrix applied</returns>
        public Bitmap Apply(Bitmap OriginalImage)
         {
             using (Graphics NewGraphics = Graphics.FromImage(NewBitmap))
             {
                 System.Drawing.Imaging.ColorMatrix NewColorMatrix = new System.Drawing.Imaging.ColorMatrix(Matrix);
                 using (ImageAttributes Attributes = new ImageAttributes())
                {
                     Attributes.SetColorMatrix(NewColorMatrix);
                     NewGraphics.DrawImage(OriginalImage,new System.Drawing.Rectangle(0,OriginalImage.Width,OriginalImage.Height),OriginalImage.Height,GraphicsUnit.Pixel,Attributes);
                 }
             }
             return NewBitmap;
         }

         #endregion
     }
 }


 /// <summary>
/// Converts an image to black and white
/// </summary>
/// <param name=\"Image\">Image to change</param>
/// <returns>A bitmap object of the black and white image</returns>
public static Bitmap ConvertBlackAndWhite(Bitmap Image)
{
     ColorMatrix TempMatrix = new ColorMatrix();
    TempMatrix.Matrix = new float[][]{
                     new float[] {.3f,.3f,0},new float[] {.59f,.59f,new float[] {.11f,.11f,new float[] {0,1,1}
                };
     return TempMatrix.Apply(Image);
}

 float[][] FloatColorMatrix ={ 
         new float[] {1,1} 
     };

    ,        调查Floyd-Steinberg抖动：http://en.wikipedia.org/wiki/Floyd%E2%80%93Steinberg_dithering 另外，如果不需要抖动，请找到平均亮度，然后将高于此亮度的所有像素变为白色，将低于此亮度的所有像素变为黑色。     ,        Chuck Conway发布的解决方案的工作版本

 /*
Copyright (c) 2010 <a href=\"http://www.gutgames.com\">James Craig</a>

 Permission is hereby granted,OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.*/

using System.Drawing;
using System.Drawing.Imaging;

namespace WebCamService {
    class ColorMatrix {

        public float[][] Matrix { get; set; }

        public Bitmap Apply(Bitmap OriginalImage) {
            using (Graphics NewGraphics = Graphics.FromImage(OriginalImage)) {
                System.Drawing.Imaging.ColorMatrix NewColorMatrix = new System.Drawing.Imaging.ColorMatrix(Matrix);
                using (ImageAttributes Attributes = new ImageAttributes()) {
                    Attributes.SetColorMatrix(NewColorMatrix);
                    NewGraphics.DrawImage(OriginalImage,Attributes);
                }
            }
            return OriginalImage;
        }

        public static Bitmap ConvertBlackAndWhite(Bitmap Image) {
            ColorMatrix TempMatrix = new ColorMatrix();
            TempMatrix.Matrix = new float[][]{
                     new float[] {.3f,1}
                };
            return TempMatrix.Apply(Image);
        }


    }
}