Develop Reference

Covert Text file to Tiff image

I am trying to convert a part of a .txt file to TIFF image, as
public static void ReadTextFileLineByLine(string fileName)//fileName- "c:\\test.txt"
{
int counter = 0;
string line;
List<string> linelist = new List<string>();
System.IO.StreamReader file = new System.IO.StreamReader(strFileName);
while ((line = file.ReadLine()) != null && counter!=19)
{
linelist.Add(line);
counter++;
}
file.Close();
ConvertlistToByteArrayToTiff(linelist);
}
public static void ConvertlistToByteArrayToTiff(List<string> list)
{
byte[] dataAsBytes = list
.SelectMany(s => System.Text.Encoding.ASCII.GetBytes(s))
.ToArray();
MemoryStream ms = new MemoryStream(dataAsBytes);
Image returnImage = Image.FromStream(ms);
returnImage.Save("c:\\133.tiff", System.Drawing.Imaging.ImageFormat.Tiff);
}
I am getting error at Image.FromStream(ms);:
Parameter is not valid.
Is my approach correct or I need to do it in different way?

Is my approach correct
No
or I need to do it in different way?
Yes
You can "print"/draw the text to an image. Like shown here: https://stackoverflow.com/a/6311628/2655508
Your assumption, that a tiffs (or any other image) representation of text, is just the ascii value of the chars isn't correct.
To read about Tiff: http://en.wikipedia.org/wiki/Tagged_Image_File_Format
To understand the structure of Tiff: See RFC 2306

OutOfMemoryException error in Loop

I am trying to create a Windows app which uploads files to FTP. Essentially, it looks for .jpeg files in a given folder, it reads through the barcodes found in the .jpg files before uploading it into the FTP server, and entering the URL into the database for our records.
As there will be multiple files at any given time in the folder, I am essentially trying to read them in a loop, and process them accordingly. However, I get an OutOfMemoryException whenever the loop starts again. I am trying to figure out what I'm doing wrong here. I have appended my code below:
private void btnProcess_Click(object sender, RoutedEventArgs e)
{
podPath = Directory.GetFiles(DestPath, "*.jpg");
List<string> scans = new List<string>(podPath.Length);
List<string> badscans = new List<string>();
byte[] imageBytes;
string filename, result;
POD conpod = new POD();
OTPOD otpod = new OTPOD();
ConsignmentObj scanJob;
//Pickup OTScan;
//Consolidate ccv;
for (int i = 0; i < podPath.Count(); i++ )
{
filename = podPath[i].ToString();
using (Bitmap bm = (Bitmap)Bitmap.FromFile(filename))
{
var results = barcodeReader.Decode(bm);
result = results.ToString();
bm.Dispose();
}
if (result != null)
{
//if barcode can be read, we throw the value into the database to pull out relevant information
if (result.Contains(ConNotePrefix))
{
#region Consignments
scanJob = getCon(result.ToString());
final = ImageFolder + "\\" + result.ToString() + ".jpg";
using (System.Drawing.Image img = System.Drawing.Image.FromFile(filename))
{
MemoryStream ms = new MemoryStream();
try
{
img.Save(ms, ImageFormat.Jpeg);
imageBytes = ms.ToArray();
img.Dispose();
}
finally
{
ms.Flush();
ms.Close();
ms.Dispose();
}
}
lock (filename)
{
if (System.IO.File.Exists(filename))
{
File.Delete(filename);
}
}
using (var stream = File.Create(final)) { }
File.WriteAllBytes(final, imageBytes);
File.Delete(filename);
conpod.ConsignmentID = scanJob.ConsignmentID;
conpod.UserID = 1;
conpod.Location = ftpUrl + "//" + result.ToString() + ".jpg";
conpod.rowguid = Guid.NewGuid();
UploadFilesToFtp(ftpUrl, ftpUser, ftpPass, final, result.ToString() + ".jpg");
insertPOD(conpod);
scans.Add(result.ToString());
#endregion
}
}
else
{
badscans.Add(filename);
}
}
this.lbScans.ItemsSource = scans;
this.lbBadScans.ItemsSource = badscans;
}
The FTP method, UploadFilesToFtp(x, x, x, x, x, x) is not a problem here. All feedback will be much appreciated.

An OutOfMemoryException can also be thrown by the method FromFile of the Image class when
The file does not have a valid image format.
or
GDI+ does not support the pixel format of the file.
So i think there is a problem with one of your image files you are reading. One solution is to catch the OutOfMemoryException and adding the file to the badscans.
try{
using (Bitmap bm = (Bitmap)Bitmap.FromFile(filename)) {
var results = barcodeReader.Decode(bm);
result = results.ToString();
bm.Dispose();
}
}
catch(OutOfMemoryException) {
badscans.add(filename);
}

Read Image file metadata

I want to upload an image file and then extract its basic information (author, dimensions, date created, modified, etc) and display it to the user. How can I do it.
A solution or reference to this problem in asp.net c# code would be helpful. But javascript or php would be ok as well.

Check this Link. You will get more Clearance about GetDetailsOf() and its File Properties based on the Win-OS version wise.
If you want to use C# code use below code to get Metadata's:
List<string> arrHeaders = new List<string>();
Shell shell = new ShellClass();
Folder rFolder = shell.NameSpace(_rootPath);
FolderItem rFiles = rFolder.ParseName(filename);
for (int i = 0; i < short.MaxValue; i++)
{
string value = rFolder.GetDetailsOf(rFiles, i).Trim();
arrHeaders.Add(value);
}

C# solution could be found here:
Link1
Link2

Bitmap image = new Bitmap(fileName);
PropertyItem[] propItems = image.PropertyItems;
foreach (PropertyItem item in propItems)
{
Console.WriteLine("iD: 0x" + item.Id.ToString("x"));
}
MSDN Reference
C# Tutorial Reference

try this...
private string doUpload()
{
// Initialize variables
string sSavePath;
sSavePath = "images/";
// Check file size (mustn’t be 0)
HttpPostedFile myFile = FileUpload1.PostedFile;
int nFileLen = myFile.ContentLength;
if (nFileLen == 0)
{
//**************
//lblOutput.Text = "No file was uploaded.";
return null;
}
// Check file extension (must be JPG)
if (System.IO.Path.GetExtension(myFile.FileName).ToLower() != ".jpg")
{
//**************
//lblOutput.Text = "The file must have an extension of JPG";
return null;
}
// Read file into a data stream
byte[] myData = new Byte[nFileLen];
myFile.InputStream.Read(myData, 0, nFileLen);
// Make sure a duplicate file doesn’t exist. If it does, keep on appending an
// incremental numeric until it is unique
string sFilename = System.IO.Path.GetFileName(myFile.FileName);
int file_append = 0;
while (System.IO.File.Exists(Server.MapPath(sSavePath + sFilename)))
{
file_append++;
sFilename = System.IO.Path.GetFileNameWithoutExtension(myFile.FileName)
+ file_append.ToString() + ".jpg";
}
// Save the stream to disk
System.IO.FileStream newFile
= new System.IO.FileStream(Server.MapPath(sSavePath + sFilename),
System.IO.FileMode.Create);
newFile.Write(myData, 0, myData.Length);
newFile.Close();
return sFilename;
}

WPF memory issue

I am trying to load pictures with the code below:
void LoadPictures(int s)
{
grdScene.Children.Clear();
TabControl tab = new TabControl();
for (int i = s; i <= s+3; i++)
{
System.Drawing.Bitmap bmp = new System.Drawing.Bitmap("C:\\img\\" + i + ".png");
TabItem tabItem = new TabItem();
tabItem.Header = "Scene " + i;
var bitmapSource = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(bmp.GetHbitmap(),
IntPtr.Zero,
Int32Rect.Empty,
BitmapSizeOptions.FromEmptyOptions());
Image image = new Image();
image.Source = bitmapSource;
tabItem.Content = image;
tab.Items.Add(tabItem);
}
grdScene.Children.Add(tab);//grdScene is Grid
}
it works fine but every time I run this method the memory is going up.
Then I tried to set all the items to null, but no success. Here is the code:
foreach (var child in grdScene.Children)
{
TabControl tab1 = (TabControl)child;
foreach (TabItem item in tab1.Items)
{
Image img = (Image)item.Content;
img = null;
}
tab1 = null;
}
I tried GC.Collect() but nothing changes. What should I do to solve this problem?

Why are you doing this via code-behind?
From the look of your code the tab items are populated entirely by the image.
You could just bind a tabcontrol to the image path collection and use a style to describe the look you're after, it'd be a lot simpler and the WPF core would then be taking care of the image loading and memory management itself.
If that's not usable for you then your issue is coming from how you're loading the image, you're doing it via an unsafe interop method that doesn't release the memory for you, you have to dispose of the bitmap youreself .Dispose()
You'd be better doing: loading the source of a BitmapImage in WPF?
Using BitmapImage is likely the better way to go if you want to remain doing it in the code-behind rather than the Interop methods.
SO:
void LoadPictures(int s)
{
grdScene.Children.Clear();
TabControl tab = new TabControl();
for (int i = s; i <= s + 3; i++)
{
BitmapImage bmp = new BitmapImage(new Uri("C:\\img\\" + i + ".png"));
TabItem tabItem = new TabItem();
tabItem.Header = "Scene " + i;
tabItem.Content = new Image(){Source = bmp};
tab.Items.Add(tabItem);
}
grdScene.Children.Add(tab);
}
Should do the trick.

Try to call Dispose on all IDisposables, such as System.Drawing.Bitmap or better use using..
using(var bmp = new System.Drawing.Bitmap("C:\\img\\" + i + ".png"))
{
.....
}

Why can I only write ONE item in my Resource.resx file?

I thought I am writing 10 file extensions and their related Icons as Bitmap into a resource file within a for loop. The odd thing is that only the last file extension with its Icon is written into the Resource.resx file. Somehow the next file extension in the loop is overwriting the previous one, but WHY ? I thought a resource is sort of a dictionary with key/value pair where I can add as much as I want just as I do in the Resource designer...
What do I wrong?
My code:
private void AddDocument()
{
OpenFileDialog fileDialog = new OpenFileDialog();
fileDialog.Multiselect = true;
DialogResult result = fileDialog.ShowDialog();
if (result == DialogResult.OK)
{
for (int i = 0; i < fileDialog.FileNames.Length; i++)
{
string absoluteFilePath = fileDialog.FileNames.GetValue(i).ToString();
byte[] file = File.ReadAllBytes(absoluteFilePath);
String fileExtension = Path.GetExtension(absoluteFilePath);
Bitmap gdiImage;
Document doc = new Document();
doc.DocumentData = file;
doc.DocumentName = fileDialog.SafeFileNames.GetValue(i).ToString();
if (TryIsFileExtensionExisting(fileExtension, out gdiImage))
{
// Filetype was saved before => Convert GDI Bitmap to wpf BitmapImage
doc.DocumentTypeImage = gdiImage.ConvertGDIImageToWPFBitmapImage();
}
else
{
BitmapImage wpfImage;
// Filetype is new => get Bitmap out of the Icon
Icon icon = IconFromFilePath(absoluteFilePath);
Bitmap bitmap = icon.ToBitmap();
wpfImage = bitmap.ConvertGDIImageToWPFBitmapImage();
doc.DocumentTypeImage = wpfImage;
// Save bitmap to resource
using (ResXResourceWriter writer = new ResXResourceWriter("TBM.Resource"))
{
writer.AddResource(fileExtension, bitmap);
writer.Generate();
}
}
DocumentList.Add(doc);
}
_documentService.AddDocumentsToPeriod(DocumentList, _parentId);
}
}
private bool TryIsFileExtensionExisting(String fileExtension, out Bitmap wpfImage)
{
DictionaryEntry entry;
using (ResXResourceReader reader = new ResXResourceReader ("TBM.Resource"))
{
entry = reader.Cast<DictionaryEntry>()
.Where(x => x.Key.ToString()
.Equals(fileExtension, StringComparison.CurrentCultureIgnoreCase))
.FirstOrDefault();
};
wpfImage = entry.Value as Bitmap;
return entry.Key != null;
}
private Icon IconFromFilePath(string filePath)
{
Icon result = null;
try
{
result = Icon.ExtractAssociatedIcon(filePath);
//'# swallow and return nothing. You could supply a default Icon here as well
}
catch
{
}
return result;
}

The problem is here:
using (ResXResourceWriter writer = new ResXResourceWriter("TBM.Resource"))
{
writer.AddResource(fileExtension, bitmap);
writer.Generate();
}
Each time you create a new writer object and write to it. But you don't have the creation of the writer object read from the old file. So you overwrite every time. You should be able to use a different constructor and solve your problem.
http://msdn.microsoft.com/en-us/library/system.resources.resxresourcewriter.aspx