Typing in lost code

I've run into that situation too, with listings so difficult that even a commercial OCR program (FineReader) couldn't handle it. At the time Tesseract was far less capable, though I haven't tried it recently to see if that has changed. Anyway, my experience was that the task was hard enough that it needed someone with knowledge of the material. It may be a contract typist could do a tolerable job but I have my doubts. Typing, say, an obsolete assembly language program if you see it merely as a random collection of characters is going to produce more errors than if the person doing the typing actually understands what the material means. One consideration is the effort required to repair transcription errors. Those that produce syntax errors aren't such an issue; those that pass the assembler or compiler but result in bugs (say, a mistyped register number) are harder to find. paul