C＃ 剪裁图片内容区域

效果:

功能:

通过过滤条件找到图片有效边缘,然后剪切

其他说明:

1.时间匆忙,代码没有组织,比较乱

2.没想到什么好算法,最土的,4次嵌套找到4个点,然后剪裁

3.过滤条件可以根据实际情况自己修改

4.嵌套循环一次跨10像素,所以最后为了避免意外,追加20像素边距.

代码:

<span style="white-space:pre">	</span>Bitmap image =new Bitmap(pictureBox1.Image);
            Bitmap new_image;

            //只保留有效区域
            int iWidth = image.Width;
            int iHeight = image.Height;


            int startX = -1;
            int startX_T = -1;
            int startY = -1;
            int startY_T = -1;



            int endX = -1;
            int endX_T = -1;
            int endY = -1;
            int endY_T = -1;


            Color colCurr;

            //通过两次嵌套确定起点xy
            for (int y = 0; y < iHeight; y = y + 10)
            {
                for (int x = 0; x < iWidth; x = x + 10)
                {
                    colCurr = image.GetPixel(x, y);                    
                    if (Convert.ToInt32( colCurr.R.ToString())<200)
                    {
                        startX_T = x;
                        startY_T = y;
                        break;
                    }
                }
                if (startX_T != -1)
                {
                    break;
                }
            }

            for (int x = 0; x < iWidth; x = x + 10)
            {
                for (int y = 0; y < iHeight; y = y + 10)
                {
                    colCurr = image.GetPixel(x, y);
                    if (Convert.ToInt32(colCurr.R.ToString()) < 200)
                    {
                        if (startX_T > x)
                        {
                            startX = x;
                        }
                        else
                        {
                            startX = startX_T;
                        }
                        if (startY_T > y)
                        {
                            startY = y;
                        }
                        else
                        {
                            startY = startY_T;
                        }
                        break;
                    }
                }
                if (startX != -1)
                {
                    break;
                }
            }



            //通过两次嵌套确定结束点xy
            for (int y = iHeight - 1; y >= 0; y = y - 10)
            {
                for (int x = iWidth - 1; x >= 0; x = x - 10)
                {
                    colCurr = image.GetPixel(x, y);
                    if (Convert.ToInt32(colCurr.R.ToString()) < 200)
                    {
                        endY_T = y;
                        endX_T = x;
                        break;
                    }

                }
                if (endY_T != -1)
                {
                    break;
                }
            }

            for (int x = iWidth - 1; x >= 0; x = x - 10)
            {
                for (int y = iHeight - 1; y >= 0; y = y - 10)
                {
                    colCurr = image.GetPixel(x, y);
                    if (Convert.ToInt32(colCurr.R.ToString()) < 200)
                    {
                        if (endX_T > x)
                        {
                            endX = endX_T;
                        }
                        else
                        {
                            endX = x;
                        }
                        if (endY_T > y)
                        {
                            endY = endY_T;
                        }
                        else
                        {
                            endY = y;
                        }
                        break;
                    }

                }
                if (endY != -1)
                {
                    break;
                }
            }

            Console.WriteLine("startX:" + startX + "startY:" + startY + "entX:" + endX + "endY:" + endY);

            //处理边缘,强制+20
            if (startX > 20)
            {
                startX = startX - 20;
            }
            else
            {
                startX = 0;
            }
            if (startY > 20)
            {
                startY = startY - 20;
            }
            else
            {
                startY = 0;
            }


            if (iWidth - endX > 20)
            {
                endX = endX + 20;
            }
            else
            {
                endX = iWidth;
            }

            if (iHeight - endY > 20)
            {
                endY = endY + 20;
            }
            else
            {
                endY = iHeight;
            }

            Rectangle cropArea = new Rectangle();
            cropArea.X = startX;
            cropArea.Y = startY;
            cropArea.Width = endX - startX;
            cropArea.Height = endY - startY;

            new_image = image.Clone(cropArea, image.PixelFormat);
            this.pictureBox2.Image = new_image;


            new_image.Save("eff_new.png", System.Drawing.Imaging.ImageFormat.Png);

程序下载:

http://download.csdn.net/detail/wenshanshan0824/9548644