Develop Reference

Using Tesseract OCR in C#

I have trying to deploy tesseract for reading the clipboard image through the code below in a C# window.form. But, a black commandline window appears and nothing happens.
private void b1_Click(object sender, EventArgs e)
{
if (ofd1.ShowDialog() == DialogResult.OK)
{
var img = new Bitmap(ofd1.FileName);
var ocr = new TessBaseAPI("./tessdata", "eng", OcrEngineMode.DEFAULT);
var page = ocr.SetImage(img);
tb1.Text = page.ToString();
}
}
The error it gives is cannot convert from 'System.Drawing.Bitmap' to 'Leptonica.Pix' hope this can be improved.

Instead of creating a bitmap, try using a Pix object like:
var img = Tesseract.Pix.LoadFromFile(ofd1.FileName)

Open an existing text file in WPF and C#

I have a program that enables a user to search text files in an open file dialog. The user is then able to open an existing text file they choose and edit it. However, my problem is that when they file opens it appears blank. What am I missing?
private void Open_Click(object sender, RoutedEventArgs e)
{
TextBox openText = new TextBox();
var OpenFile = new Microsoft.Win32.OpenFileDialog();
Nullable<bool> Success = OpenFile.ShowDialog();
OpenFile.DefaultExt = ".txt";
OpenFile.Filter = "Text documents (.txt)|*.txt";
if (Success.HasValue && Success.Value)
{
openText.Text = OpenFile.FileName;
}
else
{
//cannot open file
}
}

Replace this:
openText.Text = OpenFile.FileName;
with this:
openText.Text = System.IO.File.ReadAllText(OpenFile.FileName);

Use File.ReadAllText()
openText.Text = File.ReadAllText(OpenFile.FileName);

Saving image from "pictureBox1" to a file with a click on a button in C#

I found this code on here, and I want to save the image I get in my "pictureBox1" with a button like under, how can I implement these together?
I have the picture showing in the pictureBox1, I want to click a button and be able to store the picture on my PC.
private void button1_Click(object sender, EventArgs e)
This is the code to save image:
public static void SaveImageCapture(System.Drawing.Image image)
SaveFileDialog s = new SaveFileDialog();
s.FileName = "Image";// Default file name
s.DefaultExt = ".Jpg";// Default file extension
s.Filter = "Image (.jpg)|*.jpg"; // Filter files by extension
s.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
s.RestoreDirectory = true;
if (s.ShowDialog() == DialogResult.OK)
{
// Save Image
string filename = s.FileName;
(System.IO.FileStream fstream = new System.IO.FileStream(filename, System.IO.FileMode.Create))
{
image.Save(fstream, System.Drawing.Imaging.ImageFormat.Jpeg);
fstream.Close();

I am also not 100% sure i understand what you mean. but here is a 2 lines of codes, showing the simplest way of loading and saving an image into a picturebox.
// 1. Load a picture into the picturebox
PictureBox pic = new PictureBox() { Image = Image.FromFile("SomeFile.jpg") };
// 2. Save it to a file again
pic.Image.Save("SomeFilePath.jpg", System.Drawing.Imaging.ImageFormat.Jpeg);

I fixed it by doing this:
private void btnSave_Click(object sender, EventArgs e)
{
pictureBox1.Image.Save(#"C:\Temp\test.jpg",System.Drawing.Imaging.ImageFormat.Jpeg);
}
}

Confusion about OpenFileDialog

I am following this tutorial and downloaded source code to practice, and it works. The problem occurs when I rewrite the code: just one image is added instead of all the selected images. What am I doing wrong here?
private void button1_Click(object sender, EventArgs e)
{
ofd.Filter = "Images (*.BMP;*.JPG;*.GIF,*.PNG,*.TIFF)|*.BMP;*.JPG;*.GIF;*.PNG;*.TIFF|" +
"All files (*.*)|*.*";
ofd.Multiselect = true;
if (ofd.ShowDialog() == DialogResult.OK)
{
foreach (string name in ofd.FileNames)
{
PictureBox imageControl = new PictureBox();
imageControl.Width = 100;
imageControl.Height = 100;
Image.GetThumbnailImageAbort CallBck = new Image.GetThumbnailImageAbort(ThumbnailCallback);
Bitmap myBitmap = new Bitmap(name);
Image img = myBitmap.GetThumbnailImage(97, 97, CallBck, IntPtr.Zero);
imageControl.Image = img;
panel1.Controls.Add(imageControl);
}
}
}

I'll bet they are all being added but they're just all going on top of each other at location (0,0) in the panel (you should step through your code to check this though).
The solution: Either manually specify a location for each new PictureBox, or use a layout control such as a FlowLayoutPanel.

OCR reading using C#

I have a project which is to read character in a captured image but I'm stuck at the button which is to scan image. I ended up tesseract dll in c#, but I don't know how can I code it. I'm a newbie to this programming.
private void Browse_Click(object sender, EventArgs e)
{
//FileInfo fi = new FileInfo(string.Format(#"C:\Documents and Settings\JOrce0201610\My Documents\Visual Studio 2005\Projects\OCR Reader\{0}", imageName));
OpenFileDialog fi = new OpenFileDialog();
fi.InitialDirectory = #"C:\\Documents and Settings\JOrce0201610\My Documents\Visual Studio 2005\Projects\OCR Reader\Card";
fi.Filter = "BMP Image|*.bmp";
fi.FilterIndex = 2;
fi.RestoreDirectory = true;
if (fi.ShowDialog() == DialogResult.OK)
{
//image file path
textBox1.Text = fi.FileName;
//display image in picture box
pictureBox1.Image = new Bitmap(fi.FileName);
}
}
private void Scan_Click(object sender, EventArgs e)
{
Bitmap temp = source.Clone() as Bitmap; //Clone image to keep original image
FiltersSequence seq = new FiltersSequence();
seq.Add(Grayscale.CommonAlgorithms.BT709); //First add GrayScaling filter
seq.Add(new OtsuThreshold()); //Then add binarization(thresholding) filter
temp = seq.Apply(source); // Apply filters on source image

If you are a 'newbie' to programming, OCR is not the best place to start. The best I can suggest is that you use a webservice or existing library that can do this for you.
Microsoft has project Hawaii, Hawaii has an OCR service which is quite easy to use.