thumbnail generation error c#
i am trying to create thumbnails. my path to original folder is: suppose I:\my images**, and i want to generate it to **i:\new images. i got two problem, first problem is that if my images folder contains subfolder then in the new images it should also be in the sub folder not as a parent folder .
second i got an Error.**A generic error occurred in GDI+.
3rd i get this error: Out of memory.**
its a csharp console application
at System.Drawing.Image.Save(String filename, ImageCodecInfo encoder, EncoderParameters encoderParams)
at System.Drawing.Image.Save(String filename, ImageFormat format)
at ConsoleApplication1.Program.CreateThumbnail(String[] b, Double wid, Double hght, Boolean Isprint)
public void CreateThumbnail(string[] b, double wid, double hght, bool Isprint)
{
string[] path;
path = new string [64];
path = b;
string saveath = "i:\\check\\a test\\";
for (int i = 0; i < b.Length; i++)
{
DirectoryInfo dir = new DirectoryInfo(path[i]);
string dir1 = dir.ToString();
dir1 = dir1.Substring(dir1.LastIndexOf("\\"));
FileInfo[] files1 = dir.GetFiles();
foreach (FileInfo f in files1)
{
string gh = f.ToString();
try
{
System.Drawing.Image myThumbnail150;
System.Drawing.Image.GetThumbnailImageAbort myCallback = new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);
System.Drawing.Image imagesize = System.Drawing.Image.FromFile(f.FullName);
Bitmap bitmapNew = new Bitmap(imagesize);
double maxWidth = wid;
double maxHeight = hght;
int w = imagesize.Width;
int h = imagesize.Height;
// Longest and shortest dimension
int longestDimension = (w > h) ? w : h;
int shortestDimension = (w < h) ? w : h;
// propotionality
float factor = ((float)longestDimension) / shortestDimension;
// default width is greater than height
double newWidth = maxWidth;
double newHeight = maxWidth / factor;
// if height greater than width recalculate
if (w < h)
{
newWidth = maxHeight / factor;
newHeight = maxHeight;
}
myThumbnail150 = bitmapNew.GetThumbnailImage((int)newWidth, (int)newHeight, myCallback, IntPtr.Zero);
string ext = Path.GetExtension(f.Name);
if (!Directory.Exists(saveath + dir1))
{
Directory.CreateDirectory(saveath + dir1);
myThumbnail150.Save(saveath + dir1 + "\\" + f.Name.Replace(ext, ".Jpeg"), System.Drawing.Imaging.ImageFormat.Jpeg);
}
else if(Directory.Exists(saveath+dir1))
开发者_JAVA技巧 {
myThumbnail150.Save(saveath + dir1+" \\"+ f.Name.Replace(ext, ".Jpeg"), System.Drawing.Imaging.ImageFormat.Jpeg);
}
}
catch (Exception ex)
{
Console.WriteLine("something went wrong" + ex.ToString());
}
}
}
}
I have just refactored a bit the code and now it works (on my machine):
private static void CreateThumbnail(string[] b, double wid, double hght, bool Isprint)
{
string saveAt = "D:\\check";
foreach (string path in b)
{
var directory = new DirectoryInfo(path);
string outputPath = Path.Combine(saveAt, directory.Name);
foreach (FileInfo f in directory.GetFiles("*.*", SearchOption.AllDirectories))
{
if (f.DirectoryName != directory.FullName)
{
outputPath = Path.Combine(saveAt, directory.Name, f.Directory.Name);
}
if (!Directory.Exists(outputPath))
{
Directory.CreateDirectory(outputPath);
}
using (Image imagesize = Image.FromFile(f.FullName))
using (Bitmap bitmapNew = new Bitmap(imagesize))
{
double maxWidth = wid;
double maxHeight = hght;
int w = imagesize.Width;
int h = imagesize.Height;
// Longest and shortest dimension
int longestDimension = (w > h) ? w : h;
int shortestDimension = (w < h) ? w : h;
// propotionality
float factor = ((float)longestDimension) / shortestDimension;
// default width is greater than height
double newWidth = maxWidth;
double newHeight = maxWidth / factor;
// if height greater than width recalculate
if (w < h)
{
newWidth = maxHeight / factor;
newHeight = maxHeight;
}
string fileName = Path.Combine(outputPath, Path.GetFileNameWithoutExtension(f.Name) + ".jpeg");
bitmapNew.GetThumbnailImage((int)newWidth, (int)newHeight, () => false, IntPtr.Zero)
.Save(fileName, System.Drawing.Imaging.ImageFormat.Jpeg);
}
}
}
}
I have to say few things about your old code:
- use
foreach
when possible; - avoid the first three lines, they are useless;
- avoid unused variables;
- keep your code as clean as possible;
About the "GDI+ generic error" and the "Out Of Memory" exceptions, you should take a look at that link on SO: What is the "best" way to create a thumbnail using ASP.NET?
You must use the C# using
statement to make sure unmanaged GDI+ resources underneath the .NET surface are freed as quickly as possible to avoid out of memory errors.
The GDI+ generic can happen if the image cannot be converted for example.
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