Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Project Naptha: a browser extension that enables text selection on any image

projectnaptha.com

Post reply on HN
Print view View original

61–70 of 141 posts

Re: Project Naptha: a browser extension that enables text selection on any image

#61

Post by vidarh »

atourgates wrote: post #29

Wow - this is amazing. Right this very moment (well, a few moments ago when I wasn't procrastinating on HN) I was in the midst of extracting data from a client's old website in preparation of creating a new website. A lot of that data is contained within images. From a few preliminary tests, I'm hugely impressed. This seems on-par with any other OCR software I've used, and the fact that it happens in realtime in the…

There's actually been a bit of research on the error rates you need to beat for OCR to be cost-effective vs. having people re-type. I don't have the references handy, but I believe it's generally cost effective to OCR with error rates up to nearly 2%, and most current "consumer grade" OCR is well below 1% error rates for scans that aren't absolutely atrociously poor quality.

My Msc thesis was on reducing OCR error rates by pre-processing of various forms, and while I managed to get some reduction in error rates, one of the things I found was actually that given how low the error rates generally was to begin with, you have a very tiny budget in terms of extra processing time before further error reduction just isn't worth it - if a human needs to check the document for errors anyway, a "quick and dirty" scan+OCR is often far better than even spending the time to get "as good as possible" results. Spending even a few extra seconds per page to place the page perfectly in a scanner, or waiting a few extra seconds for more complicated processing, can be a net loss.

It's a perfect example of "worse is better": OCR, at least for typed text, is good enough today that the best available solutions aren't really worthwhile to spend resources on (for users) unless/until they give results so perfect it doesn't need to be checked by a person afterwards.

Re: Project Naptha: a browser extension that enables text selection on any image

#63

Post by antimatter15 »

x0ner wrote: post #58

Extension is awesome and while the code is messy, it has enough little jokes to keep you amused. For those looking to access the backend OCR service, it seems to be down right now, but will hopefully come back up soon. Here were the API references I could find for the remote OCR: - GET " rel="nofollow">https://sky-lighter.appspot.com/api/read/ - GET " rel="nofollow">https://sky-lighter.appspot.com/api/lookup?url= - P…

Yeah, I made the mistake of setting the App Engine budget to $1.00. Turns out that's probably not enough for a sustained run as HN's #2.

Yeah, the code is super messy, but I'd prefer if you didn't play around too much with the remote OCR service, specifically, the translation parts because Google Translate is pretty expensive per-use.

Re: Project Naptha: a browser extension that enables text selection on any image

#64

Post by omegant »

antimatter15 wrote: post #12
3JPLW wrote: post #10

The biggest thing I'd like to see is enabling in-page (control/command-f) search. In my quick scan through the page it looks like it doesn't do that… is that right? Are there plans to add invisible text to the DOM that control-f can find?

One problem with that is that it processes images lazily. It continually extrapolates cursor moments ~1 second into the future and processes those relevant parts of relevant images. But it should be possible that after an image is processed (or even eagerly by looking up previously recognized regions from the cached OCR server), the page could be made Ctrl+F-able.

Or add the option to the ctrl+F pop up "search inside the image" That way you save memory if you are not using it.

Re: Project Naptha: a browser extension that enables text selection on any image

#65

Post by [deleted] »

antimatter15 wrote: post #12
3JPLW wrote: post #10

The biggest thing I'd like to see is enabling in-page (control/command-f) search. In my quick scan through the page it looks like it doesn't do that… is that right? Are there plans to add invisible text to the DOM that control-f can find?

One problem with that is that it processes images lazily. It continually extrapolates cursor moments ~1 second into the future and processes those relevant parts of relevant images. But it should be possible that after an image is processed (or even eagerly by looking up previously recognized regions from the cached OCR server), the page could be made Ctrl+F-able.

[deleted]

Re: Project Naptha: a browser extension that enables text selection on any image

#69

Post by goldenkey »

vidarh wrote: post #61
atourgates wrote: post #29

Wow - this is amazing. Right this very moment (well, a few moments ago when I wasn't procrastinating on HN) I was in the midst of extracting data from a client's old website in preparation of creating a new website. A lot of that data is contained within images. From a few preliminary tests, I'm hugely impressed. This seems on-par with any other OCR software I've used, and the fact that it happens in realtime in the…

There's actually been a bit of research on the error rates you need to beat for OCR to be cost-effective vs. having people re-type. I don't have the references handy, but I believe it's generally cost effective to OCR with error rates up to nearly 2%, and most current "consumer grade" OCR is well below 1% error rates for scans that aren't absolutely atrociously poor quality. My Msc thesis was on reducing OCR error ra…

Time is not as relevant as energy when we are talking about people whose jobs have a huge strain.

Re: Project Naptha: a browser extension that enables text selection on any image

#70

Post by WalterBright »

vidarh wrote: post #61
atourgates wrote: post #29

Wow - this is amazing. Right this very moment (well, a few moments ago when I wasn't procrastinating on HN) I was in the midst of extracting data from a client's old website in preparation of creating a new website. A lot of that data is contained within images. From a few preliminary tests, I'm hugely impressed. This seems on-par with any other OCR software I've used, and the fact that it happens in realtime in the…

There's actually been a bit of research on the error rates you need to beat for OCR to be cost-effective vs. having people re-type. I don't have the references handy, but I believe it's generally cost effective to OCR with error rates up to nearly 2%, and most current "consumer grade" OCR is well below 1% error rates for scans that aren't absolutely atrociously poor quality. My Msc thesis was on reducing OCR error ra…

It was suggested to me by a friend that to get good OCR results, run it through the scanner/OCR twice, then diff the results. Usually one or the other will get it right, and if you run the two results through a difference editor like 'meld', it's quick to fix.
Post reply on HN