Capture2Text

Contents

What is Capture2Text?

Capture2Text enables users to do the following:

Conceptual illustration:

Download

The latest version can be found on the Capture2Text download page hosted by SourceForge. Source code is included.

How to Launch (no installation required)

  1. Unzip the contents of the zip file. Make sure that there are no Asian or other non-ASCII characters in the path where you unzipped it. Also, if you are on Windows 7, don't unzip it to the Program Files directory (this will avoid issues related to write privileges).
  2. Double-click on Capture2Text.exe. You should see the Capture2Text icon on the bottom-right of your screen (though it might be hidden in which case you will have to click on the "Show hidden icons" arrow).

OCR

Capture2Text can OCR the following languages:

Afrikaans Finnish Maltese
Albanian Frankish Norwegian
Ancient Greek French Polish
Arabic Galician Portuguese
Azerbaijani German Romanian
Basque Greek Russian
Belarusian Hebrew Serbian
Bengali Hindi Slovakian
Bulgarian Hungarian Slovenian
Catalan Icelandic Spanish
Cherokee Indonesian Swahili
Chinese (Simplified) Italian Swedish
Chinese (Traditional) Japanese Tagalog
Croatian Kannada Tamil
Czech Korean Telugu
Danish Latvian Thai
Dutch Lithuanian Turkish
English Macedonian Ukrainian
Esperanto Malay Vietnamese
Estonian Malayalam

By default only English, French, German, Italian, Japanese and Spanish are installed.

To acquire other languages:

  1. Download the appropriate OCR language dictionaries from http://code.google.com/p/tesseract-ocr/downloads/list. These files end in ".tar.gz" (ex. tesseract-ocr-3.02.rus.tar.gz).
  2. Open the ".tar.gz" file you just downloaded with 7-Zip or similar decompression software and navigate to the directory that has the file that ends in ".traineddata".
  3. Drag the ".traineddata" file (and any other file in this directory) to this path in the Capture2Text directory: Capture2Text\Utils\tesseract\tessdata
  4. Restart Capture2Text

Note: Arabic and Hindi are more CPU intensive and will thus be slower to OCR.


To install the Chinese (NHocr) language pack:

  1. Download nhocr-0.18-dic-zh_CN-091226.tar.gz from https://code.google.com/p/nhocr/downloads/list
  2. Open it with 7-Zip and copy PLM-zh_CN.dic and cctable-zh_CN to Capture2Text\Utils\nhocr\Dic
  3. Restart Capture2Text

OCR Usage

Press the OCR capture key (default: Windows Key + Q) to start the capture. Now, using your mouse, resize the capture box over the area of the screen that you want to OCR. A preview of the captured OCR'd text will appear in the top-left corner of the screen. Press the capture key again or the left mouse button to complete the capture. The captured screen area will be OCR'd and the textual result will be stored in the clipboard by default.

To cancel an OCR capture, press Esc.

To move the capture box, hold down the right mouse button and drag the mouse.

To nudge the capture box, use the arrow keys.

To toggle the active capture box corner, press the space bar.

To change the OCR language, right-click the Capture2Text tray icon, select the OCR Language option and then select the desired language.

To quickly switch between 3 languages, use the OCR language quick access keys: Windows Key + 1, Windows Key + 2, and Windows Key + 3.

When the Tesseract versions of Chinese or Japanese is selected, you should specify the text direction (vertical or horizontal) using the text direction key: Windows Key + W. The text direction will not have any effect on the NHocr Chinese or NHocr Japanese dictionaries.

(Advanced) To toggle OCR pre-processing, press Windows Key + B.

Using the Preferences dialog, you can change the following OCR settings:

Speech Recognition

Capture2Text can perform speech recognition for the following languages:

Afrikaans French Polish
Chinese German Portuguese
Czech Italian Russian
Dutch Japanese Spanish
English Korean Turkish

Speech Recognition Usage

Press the speech recognition capture key (default: Windows Key + A) to start the capture. You will see a box that says "Recording..." in the top-left corner of your screen. Speak a word or phrase or sentence into your microphone. Capture2Text will automatically recognize when you are done speaking and will display a box that says "Analyzing...". The speech recognition will take a couple of seconds. When the speech recognition is complete you will see a list of possible transcriptions to choose from. When you choose a transcription, it will be stored in the clipboard by default.

When the results windows is displayed, you can press Enter to select the first transcription or use the number keys (1-9) to select the corresponding transcription.

To cancel a speech recognition capture, press Esc.

To change the speech recognition language, right-click the Capture2Text tray icon, select the Speech Recognition Language option and then select the desired language.

To quickly toggle between 2 languages, use the speech recognition language hotkey: Windows Key + 4.

Using the Preferences dialog, you can change the following speech recognition settings:

Output Options

By default, the OCR'd or speech recognized text will be placed in the clipboard.

You also have 3 more ways to output the text.

To send the text to a pop-up window you can right-click the Capture2Text tray icon and select Show Popup Window.

To send the text to whichever textbox currently contains the blinking cursor/I-beam, right-click the Capture2Text tray icon and select Send to Cursor.

(Advanced) To send the text directly to a window/control (for example, Notepad++), first fill in the Send to Control settings in the Preferences dialog.

Using the Preferences dialog, you can change the following output settings:

Configuration

Right-click the Capture2Text tray icon in the bottom-right of your screen and then select the "Preferences..." option to bring up the Preferences dialog.

Substitutions

Sometimes Capture2Text consistently makes the same OCR mistakes such as recognizing an "M" as "I\/|".

By editing the substitutions.txt file in the Capture2Text directory, you may tell Capture2Text to substitute one text string for another text string.

Just find the appropriate language section and add one substitution per line in this format:
from_text = to_text

Example (adding 3 substitutions to the English section):

English:
I\/| = M
>< = X
some%space%text = some_text

To create a substitution regardless of language, add the substitution to the "All:" section.

Special tokens and escape characters:

%space% Space character
%tab% Tab character
%eq% Equals (=)
%perc% Percent sign (%)
%lf% Linefeed character (\n)
%cr% Carriage return character (\r)

You may disable a substitution by adding a "#" in front.

When done editing substitutions.txt, either restart Capture2Text or switch language for the substitutions to take effect.

Command Line Options

You may OCR the screen via command line by calling Capture2Text in this format:

Capture2Text.exe x1 y1 x2 y2 [output_file]

Required Arguments:
x1 - X1-Coordinate of the screen
y1 - Y1-Coordinate of the screen
x2 - X2-Coordinate of the screen
y2 - Y2-Coordinate of the screen

Optional Arguments:
output_file - The OCR'd text will be written to this file if specified.

Capture2Text will read settings.ini to determine settings such as OCR language and output options (clipboard, popup, etc.).

Examples:
Capture2Text.exe 10 152 47 321 output.txt
Capture2Text.exe 10 152 47 321

Note: Make sure that you wait for Capture2Text to finish processing before attempting to start a new instance of Capture2Text.

Troubleshooting & FAQ

Tips to Increase OCR Accuracy

How to Run Capture2Text from Source Code

  1. Download and install AutoHotkey 32-bit Unicode from: http://ahkscript.org/download/
  2. Copy the .ahk files from SourceCode/Capture2Text_AHK_Script to the root Capture2Text folder (the same folder that contains Capture2Text.exe)
  3. Double-click Capture2Text.ahk

Acknowledgments/Tools Used

Tesseract OCR engine
NHocr Alternate OCR engine for Japanese and Chinese
Leptonica Image processing and analysis library
SoX Audio utility used here to capturing voice to FLAC file
Google Voice recognition service
wget Utility used here to send voice recognition request to Google
ScreenCapture AutoHotKey screen capture script

Related Tools for Japanese Language Learners