Scale Invariant Braille Translator

Student: Yaniv Tocker Final Project in 'Introduction to Computational & Biological Vision' Course

Motivation2

Optical Character Recognition (OCR):Automatic translating of letters/digits in images

to a form that a computer can manipulate (Strings, ASCII codes)

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Scale Invariant Braille Translator

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Why is this important?Replacing data entry clerksReading car platesMaking electronic copies of books researchable

Scale Invariant Braille Translator

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Braille OCRA less investigated field of OCRCan assist the vision-impaired

Scale Invariant Braille Translator

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Braille TranslatorGoal: being able to translate braille language from

an image to English letters

Scale Invariant Braille Translator

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The system is required to be robust to scale changes, since circle can appear in different sizes

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Methods

Braille

Circle Detection

Histogram of

RadiusFind areas

Create Dictionary

Create Patch

Letter DecisionBraille

Circle Detection

Histogram of

RadiusFind areas

Create Dictionary

Create Patch

Letter Decision

Scale Invariant Braille Translator

Original ImageDetected CirclesRadius HistogramCircles filtered by common radius sizeCircles filtered by common radius size & amount of neighborsCircles MaskDynamic mask using common radiusMasks convolution resultsPoints that are local maxima & convolution result above a

threshold Braille meaningful circlesBraille meaningful circles maskBraille meaningful circles mask with centersBraille meaningful – creating patchesBraille patchesDictionary CreationDictionaryOriginal imageFirst Patch InterpretationResult

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GUIA user friendly GUI was created to easily operate

the software

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Conclusions & Future WorkA scale invariant Braille translator has been

proposedThe main key is to find the common radius in the

image & build the dictionary according to it

Scale Invariant Braille Translator

Future addition could be to detect if braille writing is in an image in order to assist the vision impaired

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References1. OCR: http://en.wikipedia.org/wiki/Optical_character_recognition2. Braille OCRhttp://en.wikipedia.org/wiki/Optical_braille_recognition3. Braille OCR examplehttp://www.ni.com/white-paper/6470/en/4. Braille code generatorhttp://braille.compelo.com/generate/5. X. fernanadez et al, “A braille O.C.R for the blind”http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.141.7727&rep=rep1&type=pdf6. J.Mennans et al,”Optical recognition of braillle writing using standard equipment”.http://bauhaus.ece.curtin.edu.au/~iain/PhD%20BU/A_Phd%20docs/To%20read/Accessibility%20info/Research/Braille_Articles/OCR%20of%20Braille.pdf7. O. ben-shahar – lecture notes from ICBV 2014 – - object classification - hough transform

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