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image processing - Improve TextRecognize[] on numbers


I have an image contain only numbers, and TextRecognize fail to recognize some numbers:


img=enter image description here;


TextRecognize[img]
(*826718*)

The documentation says that "The quality of recognized text may improve by enlarging the image", but no luck on this example


TextRecognize[ImageResize[img, Scaled[2]]]

(*826718*)

also tried different language, also no help


TextRecognize[ImageResize[img, Scaled[2]], Language -> "French"]
(*826718*)

I also tried Walfram|Alpha, it also gave the same results as Mathematica:


enter image description here


Are there some ways to solve the problem?



Answer




TextRecognize seems to be a work in progress, consider the following


Rasterize[Graphics[Text[Style["3", 100]]]] // TextRecognize
Rasterize[Graphics[Text[Style["a", 100]]]] // TextRecognize
Rasterize[Graphics[Text[Style["123", 100]]]] // TextRecognize
Rasterize[Graphics[Text[Style["1234", 100]]]] // TextRecognize
Rasterize[Graphics[Text[Style["hello", 100]]]] // TextRecognize
Rasterize[Graphics[Text[Style["hello 3", 100]]]] // TextRecognize

yields the following output


{nothing here}

{nothing here}
{nothing here}
1234
hello
hello 3

For reasons that are entirely unclear, single characters are not recognized as text, nor are numbers small "arrays" of numbers. Oddly enough, small numbers are recognized if preceeded with an actual word, making the following a terrible solution that nonetheless gives you the answer:


n = Import["http://i.stack.imgur.com/cPRrY.png"];
pretext = Rasterize["hello ", RasterSize -> 175, ImageSize -> 40];
Row[{pretext, ImageResize[n, 1000]}] // Rasterize;

t = TextRecognize@ImageResize[%, Scaled[5]];
StringSplit@t

gives the output


{hello,3482671897}

Let's hope someone comes up with a better answer...


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