合并图、切割图

拼接图

/// <summary>
        /// 拼接图
        /// 1，纵向拼接
        /// 2，白底填充
        /// 3，以最左边为准(x=0),进行拼接
        /// </summary>
        /// <param name="imageList"></param>
        /// <returns></returns>
        public static Image MergeImage(List<Image> imageList, int maxWidth = 2000)
        {
            if (imageList.Count == 0) return null;

            try
            {
                int height = imageList.Sum(x => x.Height);
                int width = Math.Min(imageList.Max(x => x.Width), maxWidth);

                // 构建空白大图
                Bitmap bitmap = new Bitmap(width, height);
                // 创建画布
                var g = Graphics.FromImage(bitmap);
                // 设置为白底
                g.Clear(Color.White);
                // 合并图
                int current_height = 0;
                foreach (var img in imageList)
                {
                    g.DrawImage(img, 0, current_height);
                    current_height += img.Height;
                }
                // 释放资源
                g.Dispose();
                return bitmap;
            }
            catch (Exception ex)
            {
                return null;
            }
        }

 

切割图

        /// <summary>
        /// 切割图
        /// 1,指定位置指大小切割图
        /// </summary>
        /// <param name="img"></param>
        /// <param name="x"></param>
        /// <param name="y"></param>
        /// <param name="width"></param>
        /// <param name="height"></param>
        /// <returns></returns>
        public static Image CutImage(Image img, int x, int y, int width, int height)
        {
            try
            {
                Bitmap bitmap = new Bitmap(width, height);
                var g = Graphics.FromImage(bitmap);
                g.Clear(Color.White);
                g.DrawImage(img, new Rectangle(0, 0, width, height), new Rectangle(x, y, width, height), GraphicsUnit.Pixel);
                g.Dispose();
                return bitmap;
            }
            catch (Exception ex)
            {
                return null;
            }
        }

        /// <summary>
        /// 切割图：将一张大图，纵向切割成若干个小图
        /// </summary>
        /// <param name="bigImage"></param>
        /// <param name="maxWidth"></param>
        /// <param name="maxHeight"></param>
        /// <returns></returns>
        public static List<Image> SplitImage(Image bigImage, int maxWidth = 2000, int maxHeight = 1500)
        {
            try
            {
                int bigHeight = bigImage.Height;
                List<Image> list = new List<Image>();
                int x = 0;
                int y = 0;
                int width = Math.Min(bigImage.Width, maxWidth);
                int height = maxHeight;

                while (y < bigHeight)
                {
                    var img = CutImage(bigImage, x, y, width, height);
                    if (img != null)
                        list.Add(img);
                    y += height;
                }

                return list;
            }
            catch (Exception ex)
            {
                return null;
            }
        }