Any way of detecting and declaring the existence of image only PDFs?

[a-singer]

I just tried to open a PDF, and it's apparently an image only one, no text. I get that there are no words, which is perfectly true, and the file is blank. Again, this is perfectly true. What I wasn't sure of was whether the PDF was bad or just full of images. I downloaded it again and, once I found the same blankness, ran it through OCR, which worked. Would it be possible and useful for PB to say "this PDF contains images only, OCR it", or something like that?

[trypsynth]

Hmm, maybe. I'll look into this once I add OCR I think. This might be quite easy though so it could end up being earlier.