c#扫描图片去黑边(扫描仪去黑边)

/// <summary>

        /// 自动去除图像扫描黑边

        /// </summary>

        /// <param name="fileName"></param>

        public static void AutoCutBlackEdge(string fileName)

        {

            //打开图像

            Bitmap bmp = OpenImage(fileName);

            RemoveBlackEdge(bmp);

            //保存图像

            SaveImage(bmp, fileName);

        }

        private static byte[] rgbValues; // 目标数组内存

        /// <summary>

        /// 图像去黑边

        /// </summary>

        /// <param name="bmp"></param>

        /// <returns></returns>

        private static Bitmap RemoveBlackEdge(Bitmap bmp)

        {

            Rectangle rect = new Rectangle(0, 0, bmp.Width, bmp.Height);

            BitmapData bmpData = bmp.LockBits(rect, ImageLockMode.ReadWrite, bmp.PixelFormat);

            // 获取图像参数 

            int w = bmpData.Width;

            int h = bmpData.Height;

            int stride = bmpData.Stride;  // 扫描线的宽度

            double picByteSize = GetPicByteSize(bmp.PixelFormat);

            int bWidth = (int)Math.Ceiling(picByteSize * w); //显示宽度

            int offset = stride - bWidth;  // 显示宽度与扫描线宽度的间隙 

            IntPtr ptr = bmpData.Scan0;   // 获取bmpData的内存起始位置 

            int scanBytes = stride * h;  // 用stride宽度，表示这是内存区域的大小

            // 分别设置两个位置指针，指向源数组和目标数组 

            int posScan = 0;

            rgbValues = new byte[scanBytes];  // 为目标数组分配内存 

            Marshal.Copy(ptr, rgbValues, 0, scanBytes);  // 将图像数据拷贝到rgbValues中 

            bool isPass = true;

            int i = 0, j = 0;

            int cutW = (int)(bWidth * 0.02); //2%宽度（可修改）

            int cutH = (int)(h * 0.02);      //2%高度（可修改）

            int posLen = (int)(picByteSize * 8); //继续查找深度为8的倍数（可修改）

            //左边

            for (i = 0; i < h; i++)

            {

                for (j = 0; j < bWidth; j++)

                {

                    isPass = true;

                    if (rgbValues[posScan] < 255) rgbValues[posScan] = 255;

                    if (rgbValues[posScan + 1] == 255)

                    {

                        for (int m = 1; m <= posLen; m++)

                        {

                            if (rgbValues[posScan + m] < 255) isPass = false;

                        }

                    }

                    if (rgbValues[posScan + 1] < 255 || bWidth / 2 < j) isPass = false;

                    recCheck(ref rgbValues, posScan, h, stride, true);

                    posScan++;

                    if (j >= cutW && isPass) break;

                }

                // 跳过图像数据每行未用空间的字节，length = stride - width * bytePerPixel 

                if (j == bWidth) posScan += offset;

                else posScan += (offset + bWidth - j - 1);

            }

            //右边

            posScan = scanBytes - 1;

            for (i = h - 1; i >= 0; i--)

            {

                posScan -= offset;

                for (j = bWidth - 1; j >= 0; j--)

                {

                    isPass = true;

                    if (rgbValues[posScan] < 255) rgbValues[posScan] = 255;

                    if (rgbValues[posScan - 1] == 255)

                    {

                        for (int m = 1; m <= posLen; m++)

                        {

                            if (rgbValues[posScan - m] < 255) isPass = false;

                        }

                    }

                    if (rgbValues[posScan - 1] < 255 || bWidth / 2 > j) isPass = false;

                    recCheck(ref rgbValues, posScan, h, stride, false);

                    posScan--;

                    if (cutH < (h - i))

                        if (j < (bWidth - cutW) && isPass) break;

                }

                // 跳过图像数据每行未用空间的字节，length = stride - width * bytePerPixel

                if (j != -1) posScan -= j;

            }

            // 内存解锁 

            Marshal.Copy(rgbValues, 0, ptr, scanBytes);

            bmp.UnlockBits(bmpData);  // 解锁内存区域 

            return bmp;

        }

        /// <summary>

        /// 上下去除黑边时，临近黑点去除

        /// </summary>

        /// <param name="rgbValues"></param>

        /// <param name="posScan"></param>

        /// <param name="h"></param>

        /// <param name="stride"></param>

        /// <param name="islLeft"></param>

        private static void recCheck(ref byte[] rgbValues, int posScan, int h, int stride, bool islLeft)

        {

            int scanBytes = h * stride;

            int cutH = (int)(h * 0.01); //临近最大1%高度（可修改）

            for (int i = 1; i <= cutH; i++)

            {

                int befRow = 0;

                if (islLeft && (posScan - stride * i) > 0)

                {

                    befRow = posScan - stride * i;

                }

                else if (!islLeft && (posScan + stride * i) < scanBytes)

                {

                    befRow = posScan + stride * i;

                }

                if (rgbValues[befRow] < 255) rgbValues[befRow] = 255;

                else break;

            }

        }

 转载 http://www.jb51.net/article/48172.htm