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I have a picture of a column with some text:

http://i.stack.imgur.com/ie9dZ.jpg

The text is really hard to make out. Is there any way I can manipulate the image to make the text stand out more and be easier to read? I have tried many things, however none worked.

I don't care if the background color gets manipulated, I just need the text to be easily visible.

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  • 3
    What result do you need? Legible text is easy by loading it into an image editor and cranking up the contrast a lot. Black-on-white lettering is a different thing, and there is a lot possible in between. – his May 17 '14 at 18:30
  • 1
    Go back and take the picture properly this time. Take several shots with the light coming from the side, but different directions over a set of pictures. The picture above looks like it was taken with the flash of a point and shoot camera, which is the worst possible lighting for what you are trying to to. – Olin Lathrop May 18 '14 at 13:06
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    Just to offer an alternative approach guys...sometimes it helps just to answer the question posed, rather than critique the purpose or point of asking in the first place. ;) – jrista May 19 '14 at 21:08
  • That is easier if you know what the goal is. Otherwise it is either a shot in the dark or a show-off of possibilities, capabilities, or knowledge. If that coincidentially helped it is the most inefficient way to do so. – his May 19 '14 at 21:32
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    The goal was clearly stated. "Is there any way I can manipulate the image to make the text stand out and be easier to read? ... I don't care if the background color gets manipulated, I just need the text to be easily visible." That is a VERY UNambiguous request. No further explanation is needed to understand what the goal is. The goal is to make the text readable, regardless of what happens to the rest of the image. – jrista May 19 '14 at 22:29
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The question, as it is asked, does not rule out this approach:

enter image description here

  • 1
    +1 for the laugh. :) One thing I'd note...by painting in what you THINK the letters are, you are quite possibly reproducing them incorrectly. If the intent was to truly discover something about the text, that couldn't be seen without processing the photo, drawing in some lines with MS Paint isn't really going to reveal anything. – jrista May 20 '14 at 18:56
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    So now that we have the letters, what does it say? Is this the ancient Greek equivalent of "No Loitering", "Chariots parked in the red zone will be towed", "Happy hour at Theo's Thursday nights at sundown", something else? – Olin Lathrop May 20 '14 at 21:03
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You can run multiple filters to bring out the text. Depending on how unimportant the stone itself is, you can take it to some significant extremes. The ultimate key is to reduce noise, as that's largely what makes the text difficult to read (Michael's image is an example of that). Here are a few filters, applied one after the other and possibly to new layers, using Photoshop, showing the results:

High Pass:

enter image description here

Purpose: Reduces large-scale contrast, making it easier to bring out contrast of medium and smaller scale information (i.e. the lettering.)
Settings:

  • Radius: 10

Reduce Noise:

enter image description here

Purpose: Reduces higher frequency information, again making it easier to bring out contrast of medium scale information. Reduce Color Noise eliminates color artifacts that make further processing difficult (color blotches end up getting enhanced with each successive filter or adjustment, making it difficult to see the text.) Settings:

  • Strength: 10
  • Preserve Details: 10
  • Reduce Color Noise: 100
  • Sharpen Details: 0

Solarize:

enter image description here

Purpose: Reduce highlight tones, darken shaded midtones (i.e. eliminate highlights and more high frequency noise, increase contrast of text).
Technique: Copy original layer first, apply Solarize filter, then set layer blending mode to overlay.

Unsharp Mask:

enter image description here

Purpose: Increase local contrast (enhances text futher). Technique: Select all, copy merged, paste as new layer before applying filter. Settings:

  • Amount: 90
  • Radius: 100
  • Threshold: 2

Contrast:

enter image description here

Purpose: Increase contrast (enhance text further.) Technique: Add Brightness/Contrast Adjustment Layer Settings:

  • Contrast: 100

Levels:

enter image description here

Purpose: Increase contrast (enhance text further.) Technique: Add Levels Adjustment Layer Settings:

  • Black Point: 65
  • Gray Point: 1.45
  • White Point: 200

Finally, if you do want to preserve some of the nature of the original photo, you can copy-merged, paste the high contrast version as a layer above the original photo, then set the blending mode to color burn; paste another copy of the layer, and set the blending mode to darken:

enter image description here

That enhances the text, without otherwise messing with the original photo.

  • One more step. Put this up full screen and take 4 steps back from your computer. I can actually see them more clearly from a distance than I could from the normal viewing distance. – Sudarshan Kadam May 20 '14 at 20:15
1

Try also to play with Project Vega (http://img-service.com/overview/overview.html). It's very powerful but also slow and hard to use. I don't know any similar program. It's not about photo-retouching, but about photo analysis.

PV is a Window software, developed by a mathematic which uses the pure algoritmic solution to enhance the images.

Concept like Fast Fourier Transform are not very known in the image processing world (as most of people know it).

PV is similar to Forensic image analysis software and it's used for Satellite image enhancement and Medical image enhancement.

If you open the website you will see that the edge recognition is one of the adviced field.

It's not opensource, neither free, but only the saving is inhibited..

  • 1
    Could you explain what Project Vega is? Is it software? What platforms does it run on? Is it open source? How would it solve the OP's problem? – MikeW May 19 '14 at 23:25
  • @MikeW: updated the answer. A +1 as a reward for the effort would be appreciated :-p – Revious May 19 '14 at 23:56
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    Or a -1 if people still think this isn't a useful answer, of course. "Pure algorithmic solution": which image processing techniques do you think aren't algorithms? "Concepts like FFT are not very well known in the image processing world": err, yes, they are. I'm still not seeing anything here which really explains why this software is a good solution. – Philip Kendall May 20 '14 at 12:41
  • @PhilipKendall: can you please put a link here to the menu of pure Photoshop, Corel or any other Photoretouch software which offer in his native menu FFT? As far as I know this kind of concepts are really famous in the theoretical image processing world, but not at all in the real world application software. Most of photoretouch software are for making picture nice, not for Forensic analysis. If you don't agree please provide some evidences. img-service.com/overview/cellular_neural_boolean_filtering.html – Revious May 20 '14 at 13:30
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    I think it is mistaken to assume that FFT isn't well understood in the image processing world. I am also not even sure it is safe to say that amateur and family photographers make up "most" image processors. I'd say most amateurs simply point, shoot, and share, without processing a all. Of those who DO process, I think there is quite a significant presence in the scientific, medical, industrial, and more advanced photography populations who do clearly understand what an FFT is. As for photoshop, photoshops tools are all ALGORITHMS, so I think it is quite inane to think PS is NOT mathematical! – jrista May 20 '14 at 21:30
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Try some of the micro-contrast plugins to help the subtle changes near edges of the inscriptions become more prominent. A few companies/toolsets come to mind: Topaz Labs makes a few tools that may help: their Detail or Adjust tools should work; I've used Flaming Pear's Organic Edges to emphasize subtle changes like that; ContrastMaster from the pluginsite(dot)com would work, too. I also like the MS Paint solution shown earlier.

1
  1. Auto levels.

    levels

  2. Blur

    blur

  3. Grain Extract

    grain extract

  4. Grain Merge – At this point, the image is suitable for a CAPTCHA system

    grain merge

  5. Local Contrast Enhancement (with G'MIC)

    local contrast enhancement

0

I had a similar issue recently with text engraved around the front of the barrel of a Cannon. What I did was actually to process it as an HDR. If you only have 1 shot, take it and make virtual copies, then set one to be -1 EV and one as +1 EV. Then process as for a normal HDR. You'll see all sorts of adaptations if you use something like Photomatix which allow for greater contrast etc. You can then also use 'ghost correction' to try and remove some of the blurriness. I don't know if that'll work but it's worth a shot!

-1

Is this good enough?

If yes, Ill update with how I did it.

enter image description here

  • 4
    That looks harder to read than the original. Too much high frequency noise. – Olin Lathrop May 19 '14 at 14:53