Sorry if I used a wrong term. What I mean is, take a picture of a snippet of e.g. a C code from a book and convert it to text. The formatting may come out wrong but most languages do not care. In pathological cases like e.g. Python, the user will have to do some post-processing.

Mine was black text on pure white background but it did not work because you could clearly see the raster in the photo, even though it was invisible with a naked eye. I am aware that this is a challenge and was not expecting miracles.