/// <summary>
/// 上传文件帮助类
/// </summary>
public class ImageUploadHelper
{ #region SaveVideoFirstImg 根据视频路径生成视频对应的图片
/// <summary>
/// 根据视频路径生成视频对应的图片
/// </summary>
/// <param name="videoUrl">视频的绝对路径</param>
public static void SaveVideoFirstImg(string videoUrl)
{
var saveFileurl = videoUrl.Substring(, videoUrl.LastIndexOf(".")) + ".jpg";
Process p = new Process();
p.StartInfo.FileName = string.Format("{0}\\ffmpeg.exe", HttpContext.Current.Server.MapPath("~/media/"));
p.StartInfo.CreateNoWindow = true;
p.StartInfo.UseShellExecute = false;
p.StartInfo.Arguments = string.Format("-i {0} -y -f image2 -t 1 {1}", videoUrl, saveFileurl);
p.Start();
p.WaitForExit();
p.Close();
p.Dispose();
}
#endregion #region CompressImg 生成缩略图方法
/// <summary>
/// 生成缩略图方法
/// </summary>
/// <param name="oldUrl">完整原始图片路径</param>
/// <param name="newUrl">完整缩略图路径</param>
/// <param name="thumbWidth">缩略图宽度</param>
/// <param name="thumbHeight">缩略图高度</param>
/// <returns>成功生成返回true，失败生成返回false</returns>
public static bool CompressImg(string oldUrl, string newUrl, double thumbWidth, double thumbHeight)
{
if (File.Exists(oldUrl))
{
//原图加载
using (System.Drawing.Image sourceImage = System.Drawing.Image.FromFile(oldUrl))
{
var imgFormate = GetImageFormat(sourceImage); //原图宽高均小于模版，不作处理，直接保存
if (sourceImage.Width <= thumbWidth && sourceImage.Height <= thumbHeight)
{
//保存
sourceImage.Save(newUrl, imgFormate);
}
else
{
//缩略图宽、高计算
double newWidth = sourceImage.Width;
double newHeight = sourceImage.Height; //宽大于高或宽等于高（横图或正方）
if (sourceImage.Width >= sourceImage.Height)
{
//如果宽大于模版
if (sourceImage.Width > thumbWidth)
{
//宽按模版，高按比例缩放
newWidth = thumbWidth;
newHeight = sourceImage.Height * (thumbWidth / sourceImage.Width);
}
}
//高大于宽（竖图）
else
{
//如果高大于模版
if (sourceImage.Height > thumbHeight)
{
//高按模版，宽按比例缩放
newHeight = thumbHeight;
newWidth = sourceImage.Width * (thumbHeight / sourceImage.Height);
}
} //判断是否为gif或者tiff图片
if (imgFormate == ImageFormat.Gif || imgFormate == ImageFormat.Tiff)
{
//压缩图片
CompressImgGif(sourceImage, imgFormate, newUrl, (int)newWidth, (int)newHeight);
}
else //其它格式图片
{
//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); //置背景色
newG.Clear(Color.Transparent); //设置质量
newG.InterpolationMode = InterpolationMode.HighQualityBicubic;
newG.SmoothingMode = SmoothingMode.HighQuality; //画图
newG.DrawImage(sourceImage, new System.Drawing.Rectangle(, , newImage.Width, newImage.Height), new System.Drawing.Rectangle(, , sourceImage.Width, sourceImage.Height), System.Drawing.GraphicsUnit.Pixel); newImage.Save(newUrl, imgFormate); //释放资源
newG.Dispose();
newImage.Dispose();
}
}
}
return true;
} return false;
}
#endregion #region CompressImgGif 压缩gif图片
/// <summary>
/// 压缩gif图片
/// </summary>
/// <param name="oldUrl"></param>
/// <param name="newUrl"></param>
/// <param name="thumbWidth"></param>
/// <param name="thumbHeight"></param>
public static void CompressImgGif(Image sourceImage, ImageFormat format, string newUrl, int width, int height)
{
//新图第一帧
Image new_img = new Bitmap(width, height); //新图其他帧
Image new_imgs = new Bitmap(width, height); //新图第一帧GDI+绘图对象
Graphics g_new_img = Graphics.FromImage(new_img); //新图其他帧GDI+绘图对象
Graphics g_new_imgs = Graphics.FromImage(new_imgs); //配置新图第一帧GDI+绘图对象
g_new_img.CompositingMode = CompositingMode.SourceCopy;
g_new_img.InterpolationMode = InterpolationMode.HighQualityBicubic;
g_new_img.PixelOffsetMode = PixelOffsetMode.HighQuality;
g_new_img.SmoothingMode = SmoothingMode.HighQuality;
g_new_img.Clear(Color.FromKnownColor(KnownColor.Transparent)); //配置其他帧GDI+绘图对象
g_new_imgs.CompositingMode = CompositingMode.SourceCopy;
g_new_imgs.InterpolationMode = InterpolationMode.HighQualityBicubic;
g_new_imgs.PixelOffsetMode = PixelOffsetMode.HighQuality;
g_new_imgs.SmoothingMode = SmoothingMode.HighQuality;
g_new_imgs.Clear(Color.FromKnownColor(KnownColor.Transparent)); //遍历维数
foreach (Guid gid in sourceImage.FrameDimensionsList)
{
//因为是缩小GIF文件所以这里要设置为Time
//如果是TIFF这里要设置为PAGE
FrameDimension f = format == ImageFormat.Gif ? FrameDimension.Time : FrameDimension.Page; //获取总帧数
int count = sourceImage.GetFrameCount(f);
//保存标示参数
System.Drawing.Imaging.Encoder encoder = System.Drawing.Imaging.Encoder.SaveFlag;
//
EncoderParameters ep = null; //每一帧
for (int c = ; c < count; c++)
{
//选择由维度和索引指定的帧
sourceImage.SelectActiveFrame(f, c);
//第一帧
if (c == )
{
//将原图第一帧画给新图第一帧
g_new_img.DrawImage(sourceImage, new Rectangle(, , new_img.Width,new_img.Height), new Rectangle(, , sourceImage.Width, sourceImage.Height), GraphicsUnit.Pixel); //把振频和透明背景调色板等设置复制给新图第一帧
for (int i = ; i < sourceImage.PropertyItems.Length; i++)
{
new_img.SetPropertyItem(sourceImage.PropertyItems[i]);
}
ep = new EncoderParameters();
//第一帧需要设置为MultiFrame
ep.Param[] = new EncoderParameter(encoder, (long)EncoderValue.MultiFrame); //保存第一帧
new_img.Save(newUrl, GetCodecInfo(format.Guid), ep);
}
//其他帧
else
{
//把原图的其他帧画给新图的其他帧
g_new_imgs.DrawImage(sourceImage, new Rectangle(, , new_imgs.Width,new_imgs.Height), new Rectangle(, , sourceImage.Width, sourceImage.Height), GraphicsUnit.Pixel); //把振频和透明背景调色板等设置复制给新图第一帧
for (int i = ; i < sourceImage.PropertyItems.Length; i++)
{
new_imgs.SetPropertyItem(sourceImage.PropertyItems[i]);
}
ep = new EncoderParameters(); //如果是GIF这里设置为FrameDimensionTime
//如果为TIFF则设置为FrameDimensionPage
ep.Param[] = new EncoderParameter(encoder, (long)(format == ImageFormat.Gif ? EncoderValue.FrameDimensionTime : EncoderValue.FrameDimensionPage)); //向新图添加一帧
new_img.SaveAdd(new_imgs, ep);
}
} ep = new EncoderParameters();
//关闭多帧文件流
ep.Param[] = new EncoderParameter(encoder, (long)EncoderValue.Flush);
new_img.SaveAdd(ep);
} //释放文件
new_img.Dispose();
new_imgs.Dispose();
g_new_img.Dispose();
g_new_imgs.Dispose();
}
#endregion #region 压缩文件
/// <summary>
/// 压缩文件
/// </summary>
/// <param name="oldImg"></param>
/// <param name="newImg"></param>
public static void CompressSize(string oldImg, string newImg)
{ using (System.Drawing.Image sourceImage = System.Drawing.Image.FromFile(oldImg))
{
Bitmap bmp = new Bitmap(sourceImage);
KiSaveAsJPEG(bmp, newImg, );
} } //// <summary>
/// 保存为JPEG格式，支持压缩质量选项
/// </summary>
/// <param name="bmp"></param>
/// <param name="FileName"></param>
/// <param name="Qty"></param>
/// <returns></returns>
public static bool KiSaveAsJPEG(Bitmap bmp, string FileName, int Qty)
{
try
{
EncoderParameter p;
EncoderParameters ps; ps = new EncoderParameters(); p = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, Qty);
ps.Param[] = p; bmp.Save(FileName, GetCodecInfo("image/jpeg"), ps); return true;
}
catch
{
return false;
}
} //// <summary>
/// 获取codeinfo
/// </summary>
/// <param name="mimeType"></param>
/// <returns>得到指定mimeType的ImageCodecInfo</returns>
private static ImageCodecInfo GetCodecInfo(string mimeType)
{
ImageCodecInfo[] CodecInfo = ImageCodecInfo.GetImageEncoders();
foreach (ImageCodecInfo ici in CodecInfo)
{
if (ici.MimeType == mimeType) return ici;
}
return null;
} /// <summary>
/// 获取codeinfo
/// </summary>
/// <param name="guid"></param>
/// <returns></returns>
public static ImageCodecInfo GetCodecInfo(Guid guid)
{
ImageCodecInfo[] icis = ImageCodecInfo.GetImageDecoders(); //为 图片编码、解码器 对象 赋值
foreach (ImageCodecInfo ici in icis)
{
if (ici.FormatID == guid)
{
return ici;
}
} return null;
}
#endregion #region GetImageFormat 获取图片文件格式
/// <summary>
/// 获取图片文件格式
/// </summary>
/// <param name="img"></param>
/// <returns></returns>
public static ImageFormat GetImageFormat(Image img)
{
if (img != null)
{
ImageFormat fileExtension = img.RawFormat,
jpgExtension = ImageFormat.Jpeg,
gifExtension = ImageFormat.Gif,
pngExtension = ImageFormat.Png,
iconExtension = ImageFormat.Icon,
bmpExtension = ImageFormat.Bmp,
tiffExtension = ImageFormat.Tiff,
wmfExtension = ImageFormat.Wmf,
emfExtension = ImageFormat.Emf,
exifExtension = ImageFormat.Exif; if (fileExtension.Equals(jpgExtension))
{
return ImageFormat.Jpeg;
}
else if (fileExtension.Equals(gifExtension))
{
return ImageFormat.Gif;
}
else if (fileExtension.Equals(pngExtension))
{
return ImageFormat.Png;
}
else if (fileExtension.Equals(iconExtension))
{
return ImageFormat.Icon;
}
else if (fileExtension.Equals(bmpExtension))
{
return ImageFormat.Bmp;
}
else if (fileExtension.Equals(tiffExtension))
{
return ImageFormat.Tiff;
}
else if (fileExtension.Equals(wmfExtension))
{
return ImageFormat.Wmf;
}
else if (fileExtension.Equals(emfExtension))
{
return ImageFormat.Emf;
}
else if (fileExtension.Equals(exifExtension))
{
return ImageFormat.Exif;
}
}
return ImageFormat.Jpeg;
}
#endregion #region GetExtension 获得上传文件的扩展名
/// <summary>
/// 获得上传文件的扩展名
/// </summary>
/// <param name="img"></param>
/// <returns></returns>
public static string GetExtension(Image img)
{
if (img != null)
{
ImageFormat fileExtension = img.RawFormat,
jpgExtension = ImageFormat.Jpeg,
gifExtension = ImageFormat.Gif,
pngExtension = ImageFormat.Png,
iconExtension = ImageFormat.Icon,
bmpExtension = ImageFormat.Bmp,
tiffExtension = ImageFormat.Tiff,
wmfExtension = ImageFormat.Wmf,
emfExtension = ImageFormat.Emf,
exifExtension = ImageFormat.Exif; if (fileExtension.Equals(jpgExtension))
{
return ".jpg";
}
else if (fileExtension.Equals(gifExtension))
{
return ".gif";
}
else if (fileExtension.Equals(pngExtension))
{
return ".png";
}
else if (fileExtension.Equals(iconExtension))
{
return ".icon";
}
else if (fileExtension.Equals(bmpExtension))
{
return ".bmp";
}
else if (fileExtension.Equals(tiffExtension))
{
return ".tiff";
}
else if (fileExtension.Equals(wmfExtension))
{
return ".wmf";
}
else if (fileExtension.Equals(emfExtension))
{
return ".emf";
}
else if (fileExtension.Equals(exifExtension))
{
return ".exif";
}
}
return ".jpg";
}
#endregion } #region UploadImageMsg 上传图片后返回上传结果
/// <summary>
/// 上传图片后返回上传结果
/// </summary>
public class UploadImageMsg
{
public UploadImageMsg()
{
error = ;
url = message = string.Empty;
} /// <summary>
/// 1错误 0成功
/// </summary>
public int error { get; set; }
/// <summary>
/// 错误信息
/// </summary>
public string message { get; set; }
/// <summary>
/// 上传成功的url路径
/// </summary>
public string url { get; set; }
}
#endregion