using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;
using System.IO;
using System.Web;
namespace Common.Utilities
{
/// <summary>
/// 图片管理类
/// </summary>
public class ImgCmdUtils
{
#region 等比缩放
/// <summary>
/// 图片等比缩放
/// </summary>
/// <remarks>吴剑 2011-01-21</remarks>
/// <param name="postedFile">原图HttpPostedFile对象</param>
/// <param name="savePath">缩略图存放地址</param>
/// <param name="targetWidth">指定的最大宽度</param>
/// <param name="targetHeight">指定的最大高度</param>
/// <param name="watermarkText">水印文字(为""表示不使用水印)</param>
/// <param name="watermarkImage">水印图片路径(为""表示不使用水印)</param>
public static void ZoomAuto(HttpPostedFileBase postedFile, string savePath, System.Double targetWidth, System.Double targetHeight, string watermarkText, string watermarkImage)
{
//创建目录
//原始图片（获取原始图片创建对象，并使用流中嵌入的颜色管理信息）
System.Drawing.Image initImage = System.Drawing.Image.FromStream(postedFile.InputStream, true);
//原图宽高均小于模版，不作处理，直接保存
if (initImage.Width <= targetWidth && initImage.Height <= targetHeight)
{
//文字水印
if (watermarkText != "")
{
using (System.Drawing.Graphics gWater = System.Drawing.Graphics.FromImage(initImage))
{
System.Drawing.Font fontWater = new Font("黑体", 30);
System.Drawing.Brush brushWater = new SolidBrush(Color.Red);
gWater.DrawString(watermarkText, fontWater, brushWater, 10, 10);
gWater.Dispose();
}
}
//透明图片水印
if (watermarkImage != "")
{
if (File.Exists(watermarkImage))
{
//获取水印图片
using (System.Drawing.Image wrImage = System.Drawing.Image.FromFile(watermarkImage))
{
//水印绘制条件：原始图片宽高均大于或等于水印图片
if (initImage.Width >= wrImage.Width && initImage.Height >= wrImage.Height)
{
Graphics gWater = Graphics.FromImage(initImage);
//透明属性
ImageAttributes imgAttributes = new ImageAttributes();
ColorMap colorMap = new ColorMap();
colorMap.OldColor = Color.FromArgb(255, 0, 255, 0);
colorMap.NewColor = Color.FromArgb(0, 0, 0, 0);
ColorMap[] remapTable = { colorMap };
imgAttributes.SetRemapTable(remapTable, ColorAdjustType.Bitmap);
float[][] colorMatrixElements = {
new float[] {1.0f, 0.0f, 0.0f, 0.0f, 0.0f},
new float[] {0.0f, 1.0f, 0.0f, 0.0f, 0.0f},
new float[] {0.0f, 0.0f, 1.0f, 0.0f, 0.0f},
new float[] {0.0f, 0.0f, 0.0f, 0.8f, 0.0f},//透明度:0.5
new float[] {0.0f, 0.0f, 0.0f, 0.0f, 1.0f}
};
ColorMatrix wmColorMatrix = new ColorMatrix(colorMatrixElements);
imgAttributes.SetColorMatrix(wmColorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);
gWater.DrawImage(wrImage,new Rectangle(initImage.Width, initImage.Height/2 , wrImage.Width, wrImage.Height/2), 0, 0, wrImage.Width, wrImage.Height, GraphicsUnit.Pixel, imgAttributes);
gWater.Dispose();
}
wrImage.Dispose();
}
}
}
//保存
initImage.Save(savePath, System.Drawing.Imaging.ImageFormat.Jpeg);
}
else
{
//缩略图宽、高计算
double newWidth = initImage.Width;
double newHeight = initImage.Height;
//宽大于高或宽等于高（横图或正方）
if (initImage.Width >= targetWidth && initImage.Width >= targetHeight)
{
//如果宽大于模版
//宽按模版，高按比例缩放
newWidth = targetWidth;
newHeight = targetHeight;
}else if (initImage.Width > initImage.Height || initImage.Width == initImage.Height)
{
//如果宽大于模版
if (initImage.Width > targetWidth)
{
//宽按模版，高按比例缩放
newWidth = targetWidth;
newHeight = initImage.Height;
}
}
//高大于宽（竖图）
else
{
//如果高大于模版
if (initImage.Height > targetHeight)
{
//高按模版，宽按比例缩放
newHeight = targetHeight;
newWidth = initImage.Width ;
}
}
//生成新图
//新建一个bmp图片
System.Drawing.Image newImage = new System.Drawing.Bitmap((int)newWidth, (int)newHeight);
//新建一个画板
System.Drawing.Graphics newG = System.Drawing.Graphics.FromImage(newImage);
//设置质量
newG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
newG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
//置背景色
newG.Clear(Color.White);
//画图
newG.DrawImage(initImage, new System.Drawing.Rectangle(0, 0, newImage.Width, newImage.Height), new System.Drawing.Rectangle(0, 0, initImage.Width, initImage.Height), System.Drawing.GraphicsUnit.Pixel);
//文字水印
if (watermarkText != "")
{
using (System.Drawing.Graphics gWater = System.Drawing.Graphics.FromImage(newImage))
{
System.Drawing.Font fontWater = new Font("宋体", 30);
System.Drawing.Brush brushWater = new SolidBrush(Color.Red);
gWater.DrawString(watermarkText, fontWater, brushWater, 10,10);
gWater.Dispose();
}
}
//透明图片水印
if (watermarkImage != "")
{
if (File.Exists(watermarkImage))
{
//获取水印图片
using (System.Drawing.Image wrImage = System.Drawing.Image.FromFile(watermarkImage))
{
//水印绘制条件：原始图片宽高均大于或等于水印图片
if (newImage.Width >= wrImage.Width && newImage.Height >= wrImage.Height)
{
Graphics gWater = Graphics.FromImage(newImage);
//透明属性
ImageAttributes imgAttributes = new ImageAttributes();
ColorMap colorMap = new ColorMap();
colorMap.OldColor = Color.FromArgb(255, 0, 255, 0);
colorMap.NewColor = Color.FromArgb(0, 0, 0, 0);
ColorMap[] remapTable = { colorMap };
imgAttributes.SetRemapTable(remapTable, ColorAdjustType.Bitmap);
float[][] colorMatrixElements = {
new float[] {1.0f, 0.0f, 0.0f, 0.0f, 0.0f},
new float[] {0.0f, 1.0f, 0.0f, 0.0f, 0.0f},
new float[] {0.0f, 0.0f, 1.0f, 0.0f, 0.0f},
new float[] {0.0f, 0.0f, 0.0f, 1f, 0.0f},//透明度:0.5
new float[] {0.0f, 0.0f, 0.0f, 0.0f, 1.0f}
};
ColorMatrix wmColorMatrix = new ColorMatrix(colorMatrixElements);
imgAttributes.SetColorMatrix(wmColorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);
gWater.DrawImage(wrImage, new Rectangle(newImage.Width - wrImage.Width, newImage.Height - wrImage.Height, wrImage.Width, wrImage.Height), 0, 0, wrImage.Width, wrImage.Height, GraphicsUnit.Pixel, imgAttributes);
gWater.Dispose();
}
wrImage.Dispose();
}
}
}
//保存缩略图
newImage.Save(savePath, System.Drawing.Imaging.ImageFormat.Jpeg);
//释放资源
newG.Dispose();
newImage.Dispose();
initImage.Dispose();
}
}
#endregion
#region 其它
/// <summary>
/// 判断文件类型是否为WEB格式图片
/// (注：JPG,GIF,BMP,PNG)
/// </summary>
/// <param name="contentType">HttpPostedFile.ContentType</param>
/// <returns></returns>
public static bool IsWebImage(string contentType)
{
if (contentType == "image/pjpeg" || contentType == "image/jpeg" || contentType == "image/gif" || contentType == "image/bmp" || contentType == "image/png")
{
return true;
}
else
{
return false;
}
}
#endregion
}
}