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This seems like it's just color fixing using stereographic distance modeling and a known reference palette. I'm not sure what is new or novel about this? Maybe

This seems like it's just color fixing using stereographic distance modeling and a known reference palette. I'm not sure what is new or novel about this? Maybe it's just new to oceanographic photography?

Pfhreak 7y ago
Inventions often seem obvious or trivial in hindsight. Are you aware of this technique being used anywhere else? Because this seems pretty novel to me.
- TrueDuality 7y ago
  Yeah both are common in astrophotography. Color correction using a reference palette is also pretty common when doing any kind of scientific imaging, though in lab setting the distance is usually well established and not relevant.
  - Semaphor 7y ago
    TFA: > Once trained, the color chart is no longer necessary. As Akkaynak helpfully explained on Reddit, “All you need is multiple images of the scene under natural light, no color chart necessary.” On Reddit: > Just a clarification: the method does NOT require the use of a color chart. That part was not clear in the video. All you need is multiple images of the scene under natural light, no color chart necessary.
    - TrueDuality 7y ago
      That makes it way more relevant.
    - jsjw7sbw 7y ago
      What annoyed me with that answer is they didn't explain why they needed the color chart at all. I would assume it's for training some model, which would lead to this method not working without the chart out of the box for example in muddy waters.
      - bayesian_horse 7y ago
        It might indeed require new training data for substantially different kinds of haze. They are only talking about reefs though, which means tropical ocean water. Coral don't thrive in muddy water.
      - juliendorra 7y ago
        The chart is needed to validate that the algorithm works: you need to have known colors in the image, you need a reference. (The chart is the ground truth) Once the chart is back to its exact color, the image can be considered corrected (at least for this distance, illumination…). If the algorithm brings the chart back to its true colors at several distances and in various conditions, then it can be applied confidently on images without a chart.
  - bayesian_horse 7y ago
    How did they get the reference palette to those stars?
- perf1 7y ago
  Apple patented something similar in 2015 regarding the recoloring part without dehaze.
kelsolaar 7y ago
They actually correct by using wavelength-dependent Backscatter and attenuation models while accounting for camera spectral sensitivities and illuminant spectrum. This is much more complex than "just color fixing". The publication shows that it is not a simple colour correction: http://openaccess.thecvf.com/content_CVPR_2019/papers/Akkaynak_Sea-Thru_A_Method_for_Removing_Water_From_Underwater_Images_CVPR_2019_paper.pdf http://openaccess.thecvf.com/content_CVPR_2019/papers/Akkayn...
- elhudy 7y ago
  It might not be "just color fixing", but to my eye at least, the results appear similar to if you were to simlpy white balance in lightroom (which doesn't always require a color chart either). Example: https://imgur.com/a/h3uFu4z https://imgur.com/a/h3uFu4z
  - jrpt 7y ago
    It's clearly much better than that. The problem is that, in a medium like water, light of different wavelengths absorb differently. So the longer distance the light travels through water, the more the effect is, and this effect is different depending on the wavelength. So you can't just open Photoshop and change the color levels of everything in the picture simultaneously. You actually have to know/estimate distances to different objects and make adjustments locally based on that.
    - elhudy 7y ago
      I'm aware how water affects light underwater; I do scuba photography. I'm sorry, but it's simply not "clearly much better than that". It's a lot of effort for very little, if any, visible difference.
chrisseaton 7y ago
> This seems like it's just color fixing using stereographic distance modeling and a known reference palette. That simple, huh?
- bayesian_horse 7y ago
  Which is already quite complicated...
  - chrisseaton 7y ago
    That was my point... did you need a sarcasm tag?
deleted 7y ago
[deleted]
altacc 7y ago
The article explains that the colour chart was only for the photos used for training the model. After the model was complete it is not needed, so the use of the software is to be able to take photos without a reference palette when doing reef surveys.

Pfhreak 7y ago

Inventions often seem obvious or trivial in hindsight. Are you aware of this technique being used anywhere else? Because this seems pretty novel to me.

TrueDuality 7y ago
Yeah both are common in astrophotography. Color correction using a reference palette is also pretty common when doing any kind of scientific imaging, though in lab setting the distance is usually well established and not relevant.
- Semaphor 7y ago
  TFA: > Once trained, the color chart is no longer necessary. As Akkaynak helpfully explained on Reddit, “All you need is multiple images of the scene under natural light, no color chart necessary.” On Reddit: > Just a clarification: the method does NOT require the use of a color chart. That part was not clear in the video. All you need is multiple images of the scene under natural light, no color chart necessary.
  - TrueDuality 7y ago
    That makes it way more relevant.
  - jsjw7sbw 7y ago
    What annoyed me with that answer is they didn't explain why they needed the color chart at all. I would assume it's for training some model, which would lead to this method not working without the chart out of the box for example in muddy waters.
    - bayesian_horse 7y ago
      It might indeed require new training data for substantially different kinds of haze. They are only talking about reefs though, which means tropical ocean water. Coral don't thrive in muddy water.
    - juliendorra 7y ago
      The chart is needed to validate that the algorithm works: you need to have known colors in the image, you need a reference. (The chart is the ground truth) Once the chart is back to its exact color, the image can be considered corrected (at least for this distance, illumination…). If the algorithm brings the chart back to its true colors at several distances and in various conditions, then it can be applied confidently on images without a chart.
- bayesian_horse 7y ago
  How did they get the reference palette to those stars?
perf1 7y ago
Apple patented something similar in 2015 regarding the recoloring part without dehaze.

kelsolaar 7y ago

They actually correct by using wavelength-dependent Backscatter and attenuation models while accounting for camera spectral sensitivities and illuminant spectrum. This is much more complex than "just color fixing". The publication shows that it is not a simple colour correction: http://openaccess.thecvf.com/content_CVPR_2019/papers/Akkaynak_Sea-Thru_A_Method_for_Removing_Water_From_Underwater_Images_CVPR_2019_paper.pdf http://openaccess.thecvf.com/content_CVPR_2019/papers/Akkayn...

elhudy 7y ago
It might not be "just color fixing", but to my eye at least, the results appear similar to if you were to simlpy white balance in lightroom (which doesn't always require a color chart either). Example: https://imgur.com/a/h3uFu4z https://imgur.com/a/h3uFu4z
- jrpt 7y ago
  It's clearly much better than that. The problem is that, in a medium like water, light of different wavelengths absorb differently. So the longer distance the light travels through water, the more the effect is, and this effect is different depending on the wavelength. So you can't just open Photoshop and change the color levels of everything in the picture simultaneously. You actually have to know/estimate distances to different objects and make adjustments locally based on that.
  - elhudy 7y ago
    I'm aware how water affects light underwater; I do scuba photography. I'm sorry, but it's simply not "clearly much better than that". It's a lot of effort for very little, if any, visible difference.

chrisseaton 7y ago

> This seems like it's just color fixing using stereographic distance modeling and a known reference palette. That simple, huh?

bayesian_horse 7y ago
Which is already quite complicated...
- chrisseaton 7y ago
  That was my point... did you need a sarcasm tag?

deleted 7y ago

[deleted]

altacc 7y ago

The article explains that the colour chart was only for the photos used for training the model. After the model was complete it is not needed, so the use of the software is to be able to take photos without a reference palette when doing reef surveys.