Live data from Hacker News

Learning to See in the Dark (2018)

github.com

31–40 of 179 posts

Re: Learning to See in the Dark (2018)

#32

It's surprising how little code [1] is needed to do this. On the other hand I feel this is quite dependent on the specific camera models and might not work on the RAW data downloaded from my phone. Happy to be corrected. [1] - https://github.com/cchen156/Learning-to-See-in-the-Dark/blob...

It's a huge amount of code, hidden behind the tensorflow import statements. It's common to credit GPUs for the rapid spread of deep learning, but good GPUs were available for quite a few years before deep learning really took off. As someone who wrote * a lot* of OpenCL code, including my own python wrappers, I'm fairly certain this code would be thousands of lines without a computation graph framework library. These…

I don't know that I agree with this first statement, but even if I do, everything is abstracted by import statements even outside ML. You say this is a huge amount of code abstracted, but it wouldn't be difficult to reimplement this in numpy and pandas directly without using tensorflow at all. The code would expand a bit, and you'd have to deal directly with backprop and calculating derivatives but it wouldn't expand things too much. But then you could make the same claim about numpy abstracting the linear algebra, and I could show you that I could extract that and do it without numpy but then it would be the python math library. It's turtles all the way down. My point is, your comment applies to everything.

Re: Learning to See in the Dark (2018)

#33
Pretty cool but seems like there’s a big limitation on this for now

“ The pretrained model probably not work for data from another camera sensor. We do not have support for other camera data. It also does not work for images after camera ISP, i.e., the JPG or PNG data.”

Would be cool to see how they come up with better models that would allow them to overcome the above limitations

Re: Learning to See in the Dark (2018)

#34
post #9
post #4

I was just wondering a couple days ago why the image from my phone is so grainy, while my eyes+brain can see everything clear in the dark (it wasn't completely dark, of course). This seems to replicate the post-processing we do in our brain (which is also a giant neural network). I wonder if the process is similar?

That's not really a good analogy. You have a totally different sensor chemistry in your eyes, as well as different processing.

And while brains are the original neural networks, they don't resemble what's going on with ML DNNs at all.

Re: Learning to See in the Dark (2018)

#35

Earlier quoted context omitted.

It's a huge amount of code, hidden behind the tensorflow import statements. It's common to credit GPUs for the rapid spread of deep learning, but good GPUs were available for quite a few years before deep learning really took off. As someone who wrote * a lot* of OpenCL code, including my own python wrappers, I'm fairly certain this code would be thousands of lines without a computation graph framework library. These…

I don't know that I agree with this first statement, but even if I do, everything is abstracted by import statements even outside ML. You say this is a huge amount of code abstracted, but it wouldn't be difficult to reimplement this in numpy and pandas directly without using tensorflow at all. The code would expand a bit, and you'd have to deal directly with backprop and calculating derivatives but it wouldn't expand…

Yup, I absolutely agree. Almost all big leaps in software engineering and applied computer science come from building a powerful and simple abstraction. Powerful and simple abstractions are surprisingly difficult to get right.

Re: Learning to See in the Dark (2018)

#36
post #18

As a photographer, the comparison to "raw" results without color balance or noise removal seems somewhat deceptive. The effects visible in the video seem easy to quickly replicate with existing techniques, such as the "surface blur" filter that averages out pixel values in areas with similar color. This happens at the expense of detail in low-contrast areas, producing a plastic-like appearance of human skin and hair,…

It would indeed be interesting to see a comparison with for instance non-local means on the scaled raw image. The speed is superior in any case, I suspect.

Re: Learning to See in the Dark (2018)

#38
post #18

As a photographer, the comparison to "raw" results without color balance or noise removal seems somewhat deceptive. The effects visible in the video seem easy to quickly replicate with existing techniques, such as the "surface blur" filter that averages out pixel values in areas with similar color. This happens at the expense of detail in low-contrast areas, producing a plastic-like appearance of human skin and hair,…

Your example strikes me as the kind of thing neural networks are much better at than a fixed filter. You or I could easily identify regions of an image where it's safe vs unsafe to do the surface averaging, and boundaries where we wouldn't want to mix up the averages. (For example, averaging text should be fine, so long as you don't cross the text boundaries.) A CNN should also be able to learn to do this pretty easily.

Re: Learning to See in the Dark (2018)

#40
post #9

Earlier quoted context omitted.

That's not really a good analogy. You have a totally different sensor chemistry in your eyes, as well as different processing.

And while brains are the original neural networks, they don't resemble what's going on with ML DNNs at all.

Low-level visual processing in the cortex share striking similarities with CNNs, actually. Gabor filters etc.
Post reply on HN