Show HN: Digitizing photos of whiteboards using the command line • Hacker News Board

Re: Show HN: Digitizing photos of whiteboards using the command line

#21

Post by goblin89 » Thu, Apr 03, 2014, 8:17 AM UTC

ollyfg wrote: post #7

Looks much better than the original photos. On a slightly related note, camscanner, an app for android (and IOS?) does something similar, but can also correct for the angle at which the photo was taken (I think it has to detect squares/rectangles in the photo). Does anyone know if this is possible using the command line too?

Looks like script "whiteboard" from the collection referenced by heisenzombie in this thread can apply relevant transformations: http://www.fmwconcepts.com/imagemagick/whiteboard/index.php

Re: Show HN: Digitizing photos of whiteboards using the command line

#22

Post by lelandbatey » Thu, Apr 03, 2014, 8:23 AM UTC

unclesaamm wrote: post #15

I'm having the same issue as magus: https://gist.github.com/lelandbatey/8677901#comment-1204432

Here's the comment I posted on the Gist, copy-pasted to here:

@molven, @vibragiel: Wow, I feel more than a bit ridiculous after looking into this. Turns out, those original examples I made using GIMP (same basic process, tuned the parameters to make it look nice). I'd originally put this gist together several months ago, and I hadn't done a thorough enough check before submitting to HN.

HOWEVER, I've since created new examples actually using the bash script, and the gist has been updated accordingly.

You can get these images here:

> Input1 - http://i.imgur.com/27aDJ6b.jpg

> Input2 - http://i.imgur.com/LaRWFT4.jpg

> Output1 - http://i.imgur.com/xMxM8P2.png

> Output2 - http://i.imgur.com/E3XoM3e.png

Re: Show HN: Digitizing photos of whiteboards using the command line

#23

Post by lelandbatey » Thu, Apr 03, 2014, 8:30 AM UTC

Synergyse wrote: post #2

Nice idea, would it be possible to do some OCR at the end?

I did experiment with using this to bring out the text in photos of books. Here's an example:

Input image - http://i.imgur.com/6o5FwxG.jpg

Output image - http://i.imgur.com/7OIOxfO.png

I tried to use vanilla Tesseract on it, but I had no luck getting anything usable out of it.

Re: Show HN: Digitizing photos of whiteboards using the command line

#24

Post by mntmn » Thu, Apr 03, 2014, 8:45 AM UTC

I'm doing an online whiteboard (spacedeck.com) and always wondering how to bridge the analog/physical world of whiteboard scribbles and sticky notes and software. How would you continue to work with these images? Attach them to a task? What is the workflow?

Re: Show HN: Digitizing photos of whiteboards using the command line

#25

Post by Myrmornis » Thu, Apr 03, 2014, 9:03 AM UTC

Very cool, I converted one and it worked well.

On a side note. I don't like gists. I didn't want to stray off topic so I put my complaints about gists here: https://news.ycombinator.com/item?id=7521600

Re: Show HN: Digitizing photos of whiteboards using the command line

#26

Post by kaeluka » Thu, Apr 03, 2014, 9:38 AM UTC

If you want to handle input file names including spaces, just wrap the $1 into parens:

#!/bin/bash

convert "$1" -morphology ...

Re: Show HN: Digitizing photos of whiteboards using the command line

#27

Post by n3t » Thu, Apr 03, 2014, 10:23 AM UTC

I'd like to see similar script for blackboards (greenboards?).

Re: Show HN: Digitizing photos of whiteboards using the command line

#28

Post by mjhoy » Thu, Apr 03, 2014, 12:42 PM UTC

Nice. Works well for drawings/comics.

http://imgur.com/a/Xvu7K

Re: Show HN: Digitizing photos of whiteboards using the command line

#29

Post by jessaustin » Thu, Apr 03, 2014, 2:37 PM UTC

kaeluka wrote: post #26

If you want to handle input file names including spaces, just wrap the $1 into parens: #!/bin/bash convert "$1" -morphology ...

Those look more like double-quotes than parens.

Re: Show HN: Digitizing photos of whiteboards using the command line

#30

Post by metatation » Thu, Apr 03, 2014, 2:52 PM UTC

This seems similar to what I've had to do with OpenCV in various iOS apps, but I think your results are more impressive than mine.

I had to sacrifice some quality in order to be able to do this with realtime video, but still, I should probably work out exactly what processing that command actually does and see if I can improve quality while still meeting the realtime requirement.

Thanks for sharing.