Thoughts on how to enhance an image |
Thoughts on how to enhance an image |
Jun 10 2009, 10:18 PM
Post
#1
|
||
Junior Member Group: Members Posts: 94 Joined: 22-May 08 From: Loughborough Member No.: 4121 |
Folks
This is certainly unrelated to UMSF (and I assume therefore not best placed in the image processing sub forum) but on the other hand is something that the massive collective experience and prowess of this place should be able to provide pertinent thoughts on (indeed I'm kicking myself for not thinking of asking earlier, having spent so long marvelling at the images generated here). Take the following image: It's actually faint text, and in fact should read the football results thus: Arsenal 0 Sunderland 0 Aston Villa 0 Chelsea 1 So my question would be what techniques might best be used to manipulate such an image to make it as legible as possible? The limit of my Photoshop ability is a simple contrast enhancement, but presumably we could be much smarter than that? Why? I hear you ask....well it harks back to work we published in Chemical Communications last December where we showed that polymerisation of disulfur dinitride is stimulated by inkjet traces. Thus minute amounts of the latter prompt the formation of the dark polymer (SN)x; minute amounts such as the residue on the inside of an envelope which has contained an inkjet printed page. Thus in the above case the results from one saturday were printed out, placed in an envelope and then sent to ourselves. Upon opening the envelope and discarding the printed page, the inside of the envelope was exposed, part of which gave the image shown (which I have reversed from the actual mirror image generated). This is one of the poorer examples, but I guess that makes it even more useful to work on. Any thoughts welcome! Thanks PFK PS What's even spookier is when you can image the contents of the envelope without opening it thanks to the even more minute amounts of inkjet diffusing right through - but that's another story |
|
|
||
Jun 15 2009, 03:07 AM
Post
#2
|
||
Member Group: Members Posts: 808 Joined: 10-October 06 From: Maynard Mass USA Member No.: 1241 |
Here is my shot at enhancing the image.
I used the original lower res version, I'll try the higher-res this week... I ran an adaptive rank order filter to soften any noise-like pixels (26.78% of pixels), while retaining all edges (i.e. adaptive using a 5x5 kernel to see the edges). I then used 4 histogram equalization filters (32x32, 64x64, 96x96, and 128x128) and ran them in a stochastic fashion over the image to convolve the varying background from the faint foreground 'characters'. You can see the artifacts from this processing on the left edge as the different filter sizes moved in a random pattern over the image. The results were obtained after about 2000 iterations, which were summed in an output array and then averaged. I think the letter inside the envelope moved around during handling and made multiple random soft and hard 'impressions' on the envelope, that resulted in the smudge-like letters -etc. I would like to see an image of the original letter that was inside this envelope (to establish ground truth). Your mileage may vary.... Cheers -------------------- CLA CLL
|
|
|
||
Lo-Fi Version | Time is now: 23rd April 2024 - 02:07 PM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE COPYRIGHT |
OPINIONS AND MODERATION Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators. |
SUPPORT THE FORUM Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member. |