.NET Exif信息在生产服务器上不起作用 [英] .NET Exif information not working on production server

问题描述

我正在读取JPEG的Exif信息以旋转图像. JPEG在ASP.NET中上传，我读取了上传流，对其进行旋转并保存.它可以在我的开发机(Windows 10，IIS 10)上正常运行，但是当我在服务器(Windows Server 2012 R2，IIS 8.5)上尝试时，它无法正常工作，并且不会加载任何Exif信息.

I'm reading the Exif information of a JPEG to rotate an image. The JPEG gets uploaded in ASP.NET and I read the upload stream, rotate it and save it. It's working perfectly on my dev machine (Windows 10, IIS 10), but when I try on the server (Windows Server 2012 R2, IIS 8.5), it doesn't work, it doesn't load any Exif information.

代码如下:

void SavePhoto()
{
    // PHOTO is the Html
    HttpPostedFile photo = Request.Files["ProfilePhoto_File"];
    using (var image = Image.FromStream(photo.InputStream, true, true))
    {
        SaveConvertingFormat(image, "output_path.jpg");
    }
}

public static void SaveConvertingFormat(Image image, string outputPath)
{
    int imageWidth = image.Width;
    int imageHeight = image.Height;

    using (var result = new Bitmap(imageWidth, imageHeight))
    {
        using (var g = Graphics.FromImage(result))
        {
            g.DrawImage(image, 0, 0, imageWidth, imageHeight);
        }

        var rotation = GetExifRotate(image, outputPath);
        // IN THE SERVER, rotation IS ALWAYS RotateNoneFlipNone
        if (rotation != RotateFlipType.RotateNoneFlipNone)
            result.RotateFlip(rotation);

        SaveJpeg(result, outputPath, 85);
    }
}

private static void SaveJpeg(this Image img, string filename, int quality)
{
    EncoderParameter qualityParam = new EncoderParameter(Encoder.Quality, (long)quality);
    ImageCodecInfo jpegCodec = GetEncoderInfo("image/jpeg");
    EncoderParameters encoderParams = new EncoderParameters(1);
    encoderParams.Param[0] = qualityParam;
    img.Save(filename, jpegCodec, encoderParams);
}

public static RotateFlipType GetExifRotate(Image img, string outputPath)
{
    // Source: https://stackoverflow.com/a/48347653/72350
    // ERROR:
    // IN THE PRODUCTION SERVER, PropertyIdList IS EMPTY!
    const int ExifOrientationId = 0x112;
    if (!img.PropertyIdList.Contains(ExifOrientationId))
        return RotateFlipType.RotateNoneFlipNone;

    var prop = img.GetPropertyItem(ExifOrientationId);
    int val = BitConverter.ToUInt16(prop.Value, 0);
    var rot = RotateFlipType.RotateNoneFlipNone;

    if (val == 3 || val == 4)
        rot = RotateFlipType.Rotate180FlipNone;
    else if (val == 5 || val == 6)
        rot = RotateFlipType.Rotate90FlipNone;
    else if (val == 7 || val == 8)
        rot = RotateFlipType.Rotate270FlipNone;

    if (val == 2 || val == 4 || val == 5 || val == 7)
        rot |= RotateFlipType.RotateNoneFlipX;

    return rot;
}

同样，上面的代码:

• 工程:Windows 10，IIS 10
• 不起作用:Windows Server 2012 R2，IIS 8.5

• Works: Windows 10, IIS 10
• Doesn't work: Windows Server 2012 R2, IIS 8.5

有什么建议吗?

推荐答案

以防万一有人遇到相同的问题.我在生产中使用WFP和GDI读取方向时遇到问题.

Just in case someone has the same issue. I had problems in production reading the orientation using WFP and GDI.

使用WPF时，错误为:

When using WPF, the error was:

System.Runtime.InteropServices.COMException (0x88982F8A): The component registration is invalid.
(Exception from HRESULT: 0x88982F8A)
at System.Windows.Media.Imaging.BitmapMetadata.GetQuery(String query)

解决方案:

唯一有效的方法是使用: https://github.com/dlemstra/Magick.NET

The only thing that worked was using: https://github.com/dlemstra/Magick.NET

代码非常简单:

var img = new MagickImage(inputStream);
img.AutoOrient();   // Fix orientation
img.Strip();        // remove all EXIF information
img.Write(outputPath);

它还帮助我删除了10条线.

It also helped me remove 10s of lines.

这篇关于.NET Exif信息在生产服务器上不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！