Command Line Usage

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Tesseract ‘man’ page

See the man page for command line syntax and other details.

FAQ

See FAQ for more examples and tips.

Available OCR Engines in Tesseract 5

Use --oem 1 for LSTM/neural network, --oem 0 for Legacy Tesseract.

Please note that Legacy Tesseract models are included in traineddata files from tessdata repo only.

tesseract input.tiff output --oem 1 -l eng

Simplest Invocation to OCR an image

tesseract imagename outputbase

This uses English as the default language and 3 as the Page Segmentation Mode. The default output format is text.

osd.traineddata, for Orientation and Segmentation and eng.traineddata and other language data files for English should be in the “tessdata” directory. TESSDATA_PREFIX environment variable should be set to the parent directory of “tessdata” directory.

The following command would give the same result as above, if eng.traineddata and osd.traineddata files are in /usr/share/tessdata directory.

tesseract --tessdata-dir /usr/share imagename outputbase -l eng --psm 3

Following examples use this image which has text in multiple languages.

Using One Language

Add ‘-l LANG’ to the command where LANG is three character language code from the list of supported languages. If this is not given then English language is assumed by default.

tesseract images/eurotext.png - -l eng

Output

The (quick) [brown] {fox} jumps! Over the $43,456.78 <lazy> #90 dog & duck/goose, as 12.5% of E-mail from [email protected] is spam. Der ,schnelle” braune Fuchs springt iiber den faulen Hund. Le renard brun «rapide» saute par-dessus le chien paresseux. La volpe marrone rapida salta sopra il cane pigro. El zorro marrén rapido salta sobre el perro perezoso. A raposa marrom ripida salta sobre o cdo preguigoso.

Using Multiple Languages

Add -l LANG[+LANG] to the command line to use multiple languages together for recognition

tesseract images/eurotext.png - -l eng+deu

Output

The (quick) [brown] {fox} jumps! Over the $43,456.78 <lazy> #90 dog & duck/goose, as 12.5% of E-mail from [email protected] is spam. Der „schnelle” braune Fuchs springt über den faulen Hund. Le renard brun «rapide» saute par-dessus le chien paresseux. La volpe marrone rapida salta sopra il cane pigro. El zorro marrén rapido salta sobre el perro perezoso. A raposa marrom räpida salta sobre o cdo preguigoso.

Order of multiple languages

The time taken for OCR as well as the output can be different based on the order of languages.

Following examples use this image which has text in multiple languages - Hindi and English.

Using English as primary language and then Hindi

time tesseract images/bilingual.png - -l eng+hin Estimating resolution as 638 हिंदी से अंग्रेजी HINDI TO ENGLISH real 0m0.442s user 0m0.622s sys 0m0.062s

Using Hindi as primary language and then English

time tesseract images/bilingual.png - -l hin+eng Estimating resolution as 638 हिंदी से अंग्रेजी HINDI TO ENGLISH real 0m0.429s user 0m0.550s sys 0m0.074s

Using script/Devanagari as primary language (it supports all languages in Devanagari script and English)

time tesseract images/bilingual.png - -l script/Devanagari Estimating resolution as 638 हिंदी से अंग्रेजी HINDI TO ENGLISH real 0m0.391s user 0m0.459s sys 0m0.093s

Use quiet configuration to suppress messages

Using quiet at end of the above command will suppress the message regarding image resolution.

time tesseract images/bilingual.png - -l script/Devanagari quiet हिंदी से अंग्रेजी HINDI TO ENGLISH real 0m0.416s user 0m0.494s sys 0m0.091s

Searchable pdf output

tesseract testing/eurotext.png testing/eurotext-eng -l eng pdf

This creates a pdf with the image and a separate searchable text layer with the recognized text.

HOCR output

Use ‘hocr’ config file by adding hocr at the end of the command to get the HOCR output.

tesseract images/eurotext.png - -l eng hocr

Partial Output

<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <title></title> <meta http-equiv="Content-Type" content="text/html;charset=utf-8"/> <meta name='ocr-system' content='tesseract 5.0.1-64-g3c22' /> <meta name='ocr-capabilities' content='ocr_page ocr_carea ocr_par ocr_line ocrx_word ocrp_wconf'/> </head> <body> <div class='ocr_page' id='page_1' title='image "images/eurotext.png"; bbox 0 0 640 500; ppageno 0; scan_res 300 300'> <div class='ocr_carea' id='block_1_1' title="bbox 61 41 574 413"> The (quick) [brown] {fox} jumps! ... salta sobre o cdo preguigoso. </div> </div> </body> </html>

TSV output

Use ‘tsv’ config file by adding tsv at the end of the command to get the TSV output.

tesseract images/eurotext.png - -l eng tsv

Partial Output

level page_num block_num par_num line_num word_num left top width height conf text 1 1 0 0 0 0 0 0 640 500 -1 2 1 1 0 0 0 61 41 513 372 -1 3 1 1 1 0 0 61 41 513 372 -1 4 1 1 1 1 0 65 41 450 30 -1 5 1 1 1 1 1 65 41 46 20 96.063751 The 5 1 1 1 1 2 128 42 89 24 95.965691 (quick) 5 1 1 1 1 3 235 43 95 25 95.835831 [brown] 5 1 1 1 1 4 349 44 66 25 94.899742 {fox} 5 1 1 1 1 5 429 45 86 26 96.683357 jumps! 4 1 1 1 2 0 65 72 490 31 -1 5 1 1 1 2 1 65 72 60 20 96.912064 Over 5 1 1 1 2 2 140 73 37 20 96.887390 the 5 1 1 1 2 3 194 73 139 24 93.263031 $43,456.78 5 1 1 1 2 4 350 76 85 25 90.893219 <lazy> 5 1 1 1 2 5 451 77 44 19 96.820717 #90 5 1 1 1 2 6 511 78 44 25 96.538940 dog 4 1 1 1 3 0 64 103 458 26 -1

Using different Page Segmentation Modes

–psm 3 - Fully automatic page segmentation, but no OSD. (Default)

Following example uses this image which has text in multiple columns.

tesseract images/2col.png - --psm 3

Cautionary Statement ON FORWARD-LOOKING STATEMENTS: This presentation includes information, statements, beliefs and opinions which are forward-looking, and which reflect current estimates, expectations and projections about future events, referred to herein as “forward-looking statements” within the meaning of the U.S> Private Securities Litigation Reform Act of 1995 or “forward-looking information” under applicable securities laws. Statements containing the words “believe”, “expect”, “continue”, “could, “potential”, “predict”, “would”, “intend”, “should”, “seek”, “anticipate”, ‘will’, “opportunity,” “positioned”, “poised,” “project”, “risk”, “plan”, “may”, “estimate” or, in each case, their Historical Information: Historical statements contained in this document regarding past trends or activities should not be taken as a representation that such trends or activities will continue in the future. In this regard, certain financial information contained herein has been extracted from, or based upon, information available in the public domain and/or provided by the Company. In particular, historical results should not be taken as a representation that such trends will be replicated in the future. No statement in this document is intended to be nor may be construed as a profit forecast.

–psm 6 - Assume a single uniform block of text.

Following examples uses this image which has a Table of Contents.

tesseract images/toc.png - --psm 6

Contents Introduction to the Tenth Anniversary Edition page xvii Afterword to the Tenth Anniversary Edition xix Preface xxi Acknowledgements xxvii Nomenclature and notation xxix Part I Fundamental concepts 1 1 Introduction and overview 1 1.1 Global perspectives 1 1.11 History of quantum computation and quantum information 2 1.1.2 Future directions 12 1.2 Quantum bits 13 1.2.1 Multiple qubits 16 1.3 Quantum computation 17 1.3.1 Single qubit gates 17 1.3.2 Multiple qubit gates 20 1.3.3 Measurements in bases other than the computational basis 2 1.34 Quantum circuits 2 1.3.5 Qubit copying circuit? 24

Use -c preserve_interword_spaces=1 to preserve spaces

tesseract images/toc.png - --psm 6 -c preserve_interword_spaces=1

Use pdftotext for preserving layout for text output

tesseract images/toc.png images/toc -l eng –psm 11 pdf

pdftotext -layout images/toc.pdf -

Contents Introduction to the Tenth Anniversary Edition page xvii Afterword to the Tenth Anniversary Edition xix Preface xxi Acknowledgements xx Nomenclature and notation xxix Part I Fundamental concepts 1 Introduction and overview 1.1 Global perspectives 1.11 History of quantum computation and quantum information 1.1.2 Future directions 12 12 Quantum bits 13 1.2.1 Multiple qubits 16 1.3 Quantum computation 17 Single qubit gates 2 Multiple qubit gates 20 Measurements in bases other than the computational basis 2 4 Quantum circu 2 5 Qubit copying circuit? 24

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