Question:
I've made a homepage for my brother, accessible here:
http://www.daniel-steiger.ch
It uses Microsoft ASP.NET MVC3 on Linux with mono 3, over fastcgi with nginx (plus my own DNS server).
Now I know this is an unusual constellation, but so far, it all works fine.
However, I ran into a minor very subtle bug.
When in the gallery one clicks on a thumbnail image, I wanted to display the full-sized image via the FullImage method of the gallery controller in a new tab.
For example, this direct url:
http://www.daniel-steiger.ch/gallery/FullImage/001.jpg
In internet Explorer, I got the image as text instead.
In all other browsers displayed an "invalid image" message.
I solved the problem by calling the image via it's direct file URL, which works fine:
http://www.daniel-steiger.ch/Content/images/gallery/001.jpg?LastWriteTimeUTC=1358694795000
Subsequently, I reported the bug to the mono mailing list
http://mono.1490590.n4.nabble.com/Bug-in-mono-3-0-1-MVC3-File-FileResult-td4658382.html
Now I got as a response, that this is all my fault, because I set the wrong image mime type, which is/was true.
However, I found it strange that if that was the case, the same code works fine on Windows, plus smart browsers like Chrome usually detect a wrong mime setting and use the correct one.
So I changed the mime-type from "image/jpg" to "image/jpeg", and redeployed the project to the server.
I also checked with the file utility if the image is actually a jpeg image, and it is.
What is strange is that it still doesn't show the image.
On internet explorer, I now get "not available".
On all other browsers, I get: the image cannot be displayed because it contains errors.
I did now wget the image from the URL where the image contains errors.
wget http://www.daniel-steiger.ch/gallery/fullimage/001.jpg
Then I ran a binary compare between the invalid and the original file:
cmp -l 001.jpg 001a.jpg | awk '{printf "%08X %02X %02X\n", $1, strtonum(0$2), strtonum(0$3)}' >> comparison.txt
And this is the comparison result:
What springs into my eye, is that the image that internet explorer says he cannot find is actually 1.7 MB in size, and contains the extra bytes:
31 39 36 62 36 38 0D 0A
at the beginning...
Anybody has an idea what's going wrong here/ where these bytes could come from (apart from the fact that it's most likely from a bug in mono/fastcgi) ?
This is the new controller code btw:
namespace Homepage.Controllers
{
public class GalleryController : Controller
{
protected static string GetImageDirectory()
{
string bd = AppDomain.CurrentDomain.BaseDirectory;
string strImageDirectory = System.IO.Path.Combine(bd,
"Content");
strImageDirectory =
System.IO.Path.Combine(strImageDirectory, "images");
strImageDirectory =
System.IO.Path.Combine(strImageDirectory, "gallery");
return strImageDirectory;
} // End Function GetImageDirectory
protected static string strImageDirectory = GetImageDirectory();
public FileResult FullImage(string id)
{
string strFileName =
System.IO.Path.Combine(strImageDirectory, id);
//return new FilePathResult("CorrectFullPathAndFileName", "CorrectMime");
//return File(strFileName, "image/jpg"); // Old
return File(strFileName, "image/jpeg"); // New
} // End Action FullImage
public FileResult Thumb(string id)
{
//return Redirect(id);
string strFileName =
System.IO.Path.Combine(strImageDirectory, id);
System.IO.Stream ms =
Tools.Imaging.GetThumbnailStream(strFileName,
System.Drawing.Imaging.ImageFormat.Png);
return File(ms, "image/png");
/*
using (System.IO.Stream ms =
Tools.Imaging.GetThumbnailStream(strFileName,
System.Drawing.Imaging.ImageFormat.Png))
{
return File(ms, "image/png");
}*/
} // End Action Thumb
} // End Class GalleryController : Controller
} // End Namespace Homepage.Controllers
Edit:
it gets stranger:
There is also an extra sequence with
0d 0a 0d 0a 30 0d 0a 0d 0a
at the end...
I just did the hexdump, and found the original file has filesize (hold your breath):
00196b68
Here the hexdumps (8 MB each):
Canonical format (hexdump -C 001.jpg > 001.txt):
Original file: http://www.daniel-steiger.ch/001.txt
Botched file: http://www.daniel-steiger.ch/001a.txt
Pure dump (hexdump 001.jpg > 001_1.txt):
Original file: http://www.daniel-steiger.ch/001_1.txt
Botched file: http://www.daniel-steiger.ch/001a_1.txt
Hmmm, the hex dump for the botched files is 5 MB, the one for the original is 8.2 MB...
I use the latest stable nginx:
sudo -s
nginx=stable # use nginx=development for latest development version
add-apt-repository ppa:nginx/$nginx
apt-get update
apt-get install nginx
The full code for Tools.Imaging (renamed Tools to MvcTools in the meantime, to match the assembly namespace)
using System;
using System.Text;
namespace MvcTools
{
public class Imaging
{
//public static System.Drawing.Size m_sMaxThumbNailDimensions = new System.Drawing.Size(200, 200);
public static System.Drawing.Size m_sMaxThumbNailDimensions = new System.Drawing.Size(300, 300);
public static System.IO.Stream GetImageAsStream(
string strOrgFileName
, System.Drawing.Imaging.ImageFormat ifOutputFormat
)
{
return GetImageAsStream(strOrgFileName, ifOutputFormat, 1024);
} // End Function GetImage
public static System.IO.Stream GetImageAsStream(
string strOrgFileName
,System.Drawing.Imaging.ImageFormat ifOutputFormat
,int rez
)
{
System.IO.MemoryStream ms = null;
if (!System.IO.File.Exists(strOrgFileName))
throw new System.IO.FileNotFoundException(strOrgFileName);
try
{
using (System.Drawing.Image imgSourceImage = System.Drawing.Image.FromFile(strOrgFileName))
{
ms = new System.IO.MemoryStream();
imgSourceImage.Save(ms, ifOutputFormat);
ms.Position = 0;
} // End Using imgSourceImage
} // End Try
catch (Exception ex)
{
System.Windows.Forms.MessageBox.Show(ex.GetType().ToString());
System.Windows.Forms.MessageBox.Show(ex.Message);
//Response.Write(ex.Message);
} // End Catch
return ms;
} // End Function GetImageAsStream
public static System.Drawing.Size GetThumbnailSize(string strOrgFileName)
{
System.Drawing.Size sThumbNailSizeToUse = new System.Drawing.Size();
try
{
using (System.Drawing.Image imgSourceImage = System.Drawing.Image.FromFile(strOrgFileName))
{
decimal decPixToSubstract = 0;
decimal decPercentage;
if (m_sMaxThumbNailDimensions.Width < imgSourceImage.Size.Width || m_sMaxThumbNailDimensions.Height < imgSourceImage.Size.Height)
{
if (imgSourceImage.Size.Width > imgSourceImage.Size.Height)
{
decPercentage = (((decimal)imgSourceImage.Size.Width - (decimal)m_sMaxThumbNailDimensions.Width) / (decimal)imgSourceImage.Size.Width);
decPixToSubstract = decPercentage * imgSourceImage.Size.Height;
sThumbNailSizeToUse.Width = m_sMaxThumbNailDimensions.Width;
sThumbNailSizeToUse.Height = imgSourceImage.Size.Height - (int)decPixToSubstract;
} // End if (imgSourceImage.Size.Width > imgSourceImage.Size.Height)
else
{
decPercentage = (((decimal)imgSourceImage.Size.Height - (decimal)m_sMaxThumbNailDimensions.Height) / (decimal)imgSourceImage.Size.Height);
decPixToSubstract = decPercentage * (decimal)imgSourceImage.Size.Width;
sThumbNailSizeToUse.Height = m_sMaxThumbNailDimensions.Height;
sThumbNailSizeToUse.Width = imgSourceImage.Size.Width - (int)decPixToSubstract;
} // End else of if (imgSourceImage.Size.Width > imgSourceImage.Size.Height)
} // End if (m_sMaxThumbNailDimensions.Width < imgSourceImage.Size.Width || m_sMaxThumbNailDimensions.Height < imgSourceImage.Size.Height)
else
{
sThumbNailSizeToUse.Width = imgSourceImage.Size.Width;
sThumbNailSizeToUse.Height = imgSourceImage.Size.Height;
} // End else of if (m_sMaxThumbNailDimensions.Width < imgSourceImage.Size.Width || m_sMaxThumbNailDimensions.Height < imgSourceImage.Size.Height)
} // End Using imgSourceImage
} // End Try
catch (Exception ex)
{
System.Windows.Forms.MessageBox.Show(ex.Message);
//Response.Write(ex.Message);
} // End Catch
return sThumbNailSizeToUse;
} // End Sub GetThumbnailSize(string strOrgFileName)
// http://stackoverflow.com/questions/7319842/mvc3-razor-thumbnail-resize-image-ideas
// http://stackoverflow.com/questions/1528525/alternatives-to-system-drawing-for-use-with-asp-net/1528908#1528908
public static void GenerateThumbnailFile(
string strPhysicalPath,
string strOrgFileName, string strThumbnailFileName,
System.Drawing.Imaging.ImageFormat ifOutputFormat, int rez
)
{
try
{
using (System.Drawing.Image imgSourceImage = System.Drawing.Image.FromFile(strOrgFileName))
{
//System.Drawing.Image oImg = System.Drawing.Image.FromStream(fil.InputStream);
decimal decPixToSubstract = 0;
decimal decPercentage;
//default
System.Drawing.Size sThumbNailSizeToUse = new System.Drawing.Size();
if (m_sMaxThumbNailDimensions.Width < imgSourceImage.Size.Width || m_sMaxThumbNailDimensions.Height < imgSourceImage.Size.Height)
{
if (imgSourceImage.Size.Width > imgSourceImage.Size.Height)
{
decPercentage = (((decimal)imgSourceImage.Size.Width - (decimal)m_sMaxThumbNailDimensions.Width) / (decimal)imgSourceImage.Size.Width);
decPixToSubstract = decPercentage * imgSourceImage.Size.Height;
sThumbNailSizeToUse.Width = m_sMaxThumbNailDimensions.Width;
sThumbNailSizeToUse.Height = imgSourceImage.Size.Height - (int)decPixToSubstract;
} // End if (imgSourceImage.Size.Width > imgSourceImage.Size.Height)
else
{
decPercentage = (((decimal)imgSourceImage.Size.Height - (decimal)m_sMaxThumbNailDimensions.Height) / (decimal)imgSourceImage.Size.Height);
decPixToSubstract = decPercentage * (decimal)imgSourceImage.Size.Width;
sThumbNailSizeToUse.Height = m_sMaxThumbNailDimensions.Height;
sThumbNailSizeToUse.Width = imgSourceImage.Size.Width - (int)decPixToSubstract;
} // End else of if (imgSourceImage.Size.Width > imgSourceImage.Size.Height)
} // End if (m_sMaxThumbNailDimensions.Width < imgSourceImage.Size.Width || m_sMaxThumbNailDimensions.Height < imgSourceImage.Size.Height)
else
{
sThumbNailSizeToUse.Width = imgSourceImage.Size.Width;
sThumbNailSizeToUse.Height = imgSourceImage.Size.Height;
} // End else of if (m_sMaxThumbNailDimensions.Width < imgSourceImage.Size.Width || m_sMaxThumbNailDimensions.Height < imgSourceImage.Size.Height)
using (System.Drawing.Bitmap bmpThumbnail = new System.Drawing.Bitmap(sThumbNailSizeToUse.Width, sThumbNailSizeToUse.Height))
{
bmpThumbnail.SetResolution(rez, rez);
using (System.Drawing.Image imgThumbNail = bmpThumbnail)
{
using (System.Drawing.Graphics gGraphicsContext = System.Drawing.Graphics.FromImage(imgThumbNail))
{
gGraphicsContext.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
gGraphicsContext.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
gGraphicsContext.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
System.Drawing.Rectangle rThumbnailDimension = new System.Drawing.Rectangle(0, 0, sThumbNailSizeToUse.Width, sThumbNailSizeToUse.Height);
gGraphicsContext.DrawImage(imgSourceImage, rThumbnailDimension);
} // End Using gGraphicsContext
imgThumbNail.Save(System.IO.Path.Combine(strPhysicalPath, strThumbnailFileName), ifOutputFormat);
} // End Using imgThumbNail
} // End Using bmpThumbnail
} // End Using imgSourceImage
} // End Try
catch (Exception ex)
{
System.Windows.Forms.MessageBox.Show(ex.Message);
//Response.Write(ex.Message);
} // End Catch
} // End Function GenerateThumbNail
public static System.IO.Stream GetThumbnailStream(
string strOrgFileName
, System.Drawing.Imaging.ImageFormat ifOutputFormat
)
{
return GetThumbnailStream(strOrgFileName, ifOutputFormat, 1024);
} // End Function GetThumbnailStream
public static System.IO.Stream GetThumbnailStream(
string strOrgFileName
,System.Drawing.Imaging.ImageFormat ifOutputFormat
,int rez
)
{
System.IO.MemoryStream ms = null;
try
{
using (System.Drawing.Image imgSourceImage = System.Drawing.Image.FromFile(strOrgFileName))
{
decimal decPixToSubstract = 0;
decimal decPercentage;
System.Drawing.Size sThumbNailSizeToUse = new System.Drawing.Size();
if (m_sMaxThumbNailDimensions.Width < imgSourceImage.Size.Width || m_sMaxThumbNailDimensions.Height < imgSourceImage.Size.Height)
{
if (imgSourceImage.Size.Width > imgSourceImage.Size.Height)
{
decPercentage = (((decimal)imgSourceImage.Size.Width - (decimal)m_sMaxThumbNailDimensions.Width) / (decimal)imgSourceImage.Size.Width);
decPixToSubstract = decPercentage * imgSourceImage.Size.Height;
sThumbNailSizeToUse.Width = m_sMaxThumbNailDimensions.Width;
sThumbNailSizeToUse.Height = imgSourceImage.Size.Height - (int)decPixToSubstract;
} // End if (imgSourceImage.Size.Width > imgSourceImage.Size.Height)
else
{
decPercentage = (((decimal)imgSourceImage.Size.Height - (decimal)m_sMaxThumbNailDimensions.Height) / (decimal)imgSourceImage.Size.Height);
decPixToSubstract = decPercentage * (decimal)imgSourceImage.Size.Width;
sThumbNailSizeToUse.Height = m_sMaxThumbNailDimensions.Height;
sThumbNailSizeToUse.Width = imgSourceImage.Size.Width - (int)decPixToSubstract;
} // End else of if (imgSourceImage.Size.Width > imgSourceImage.Size.Height)
} // End if (m_sMaxThumbNailDimensions.Width < imgSourceImage.Size.Width || m_sMaxThumbNailDimensions.Height < imgSourceImage.Size.Height)
else
{
sThumbNailSizeToUse.Width = imgSourceImage.Size.Width;
sThumbNailSizeToUse.Height = imgSourceImage.Size.Height;
} // End else of if (m_sMaxThumbNailDimensions.Width < imgSourceImage.Size.Width || m_sMaxThumbNailDimensions.Height < imgSourceImage.Size.Height)
using (System.Drawing.Bitmap bmpThumbnail = new System.Drawing.Bitmap(sThumbNailSizeToUse.Width, sThumbNailSizeToUse.Height))
{
bmpThumbnail.SetResolution(rez, rez);
using (System.Drawing.Image imgThumbNail = bmpThumbnail)
{
using (System.Drawing.Graphics gGraphicsContext = System.Drawing.Graphics.FromImage(imgThumbNail))
{
gGraphicsContext.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
gGraphicsContext.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
gGraphicsContext.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
System.Drawing.Rectangle rThumbnailDimension = new System.Drawing.Rectangle(0, 0, sThumbNailSizeToUse.Width, sThumbNailSizeToUse.Height);
gGraphicsContext.DrawImage(imgSourceImage, rThumbnailDimension);
ms = new System.IO.MemoryStream();
imgThumbNail.Save(ms, ifOutputFormat);
ms.Position = 0;
} // End Using gGraphicsContext
} // End Using imgThumbNail
} // End Using bmpThumbnail
/*
byte[] buffer = null;
using (System.IO.MemoryStream ms = new System.IO.MemoryStream())
{
imgThumbNail.Save(ms, ifOutputFormat);
buffer = ms.ToArray();
}
*/
// Exerts from Page_Load method
//Response.ContentType = "image/" + extension;
//Response.OutputStream.Write(pBuffer, 0, pBuffer.Length);
//Response.End();
//imgThumbNail.Save(System.IO.Path.Combine(strPhysicalPath, strThumbnailFileName), ifOutputFormat);
} // End Using imgSourceImage
} // End Try
catch (Exception ex)
{
//Console.WriteLine(ex.Message);
System.Windows.Forms.MessageBox.Show(ex.Message);
//Response.Write(ex.Message);
} // End Catch
//System.Windows.Forms.MessageBox.Show("image/" + ifOutputFormat.ToString().ToLower());
return ms;
} // End Function GenerateThumbNail
} // End Class Imaging
} // End Namespace Tools
