3 ms·

I wonder if the same techniques could be used for compression as well.

irixusr 11y ago
If you mean lossy, why not? Netflix could use this by reducing the information they send out to their users who recreate a lot of what was lost. I don't think for loss-less though, because they are inferring what a pixel should to be, i.e. they cannot be 100% any bit is every set right, just the probability that it is.
foota 11y ago
I believe this is already somewhat similar to say zip compression, which can reference other portions of the compressed file.
Houshalter 11y ago
Absolutely. For lossless compression you just need to encode the difference between the predicted pixels and the actual pixels. Which hopefully has a lot of zeros, making it easier to compress. For lossy compression, you just throw away some or all of the difference info. The biggest issue is speed. This doesn't look very fast to encode or decode. That's the biggest issue with new image compression algorithms, and makes it nonviable for most purposes.
nitrogen 11y ago
Some photocopiers have actually replaced numbers with different numbers in copied documents because of pattern-based compression: https://news.ycombinator.com/item?id=6156238 https://news.ycombinator.com/item?id=6156238
- ansgri 11y ago
  Photocopiers use Mixed Raster Content (MRC) with JBIG compression, which is indeed able to confuse symbols at the same scale, but across-the-scales substitution is beyond the current MRC capabilities afaik.
  - murbard2 11y ago
    One way around that problem is to use lossless compression. Unfortunately, if you have merely 1 bit of static noise per pixel (so +/- 0.4% intensity), you won't achieve better than 12.5% compression.
beagle3 11y ago
Yes, and this was all the rage in the late '80s and early '90s. Everyone was sure this will replace JPEGs. See http://www.cs.northwestern.edu/~agupta/_projects/image_processing/web/FractalImageCompression/ http://www.cs.northwestern.edu/~agupta/_projects/image_proce... for a description. Spoiler: It didn't happen. Fractal compression mostly matched JPEG on rate/quality ; it didn't improve on it, though; and it was horrible in both memory use, run time, and memory requirements compared to JPEG. So JPEG it (still) is. Another Spoiler: If file size was the criterion, BPG would be replacing JPEG these days. That isn't happening either.

If you mean lossy, why not? Netflix could use this by reducing the information they send out to their users who recreate a lot of what was lost. I don't think for loss-less though, because they are inferring what a pixel should to be, i.e. they cannot be 100% any bit is every set right, just the probability that it is.

foota 11y ago

I believe this is already somewhat similar to say zip compression, which can reference other portions of the compressed file.

Houshalter 11y ago

Absolutely. For lossless compression you just need to encode the difference between the predicted pixels and the actual pixels. Which hopefully has a lot of zeros, making it easier to compress. For lossy compression, you just throw away some or all of the difference info. The biggest issue is speed. This doesn't look very fast to encode or decode. That's the biggest issue with new image compression algorithms, and makes it nonviable for most purposes.

nitrogen 11y ago

Some photocopiers have actually replaced numbers with different numbers in copied documents because of pattern-based compression: https://news.ycombinator.com/item?id=6156238 https://news.ycombinator.com/item?id=6156238

ansgri 11y ago
Photocopiers use Mixed Raster Content (MRC) with JBIG compression, which is indeed able to confuse symbols at the same scale, but across-the-scales substitution is beyond the current MRC capabilities afaik.
- murbard2 11y ago
  One way around that problem is to use lossless compression. Unfortunately, if you have merely 1 bit of static noise per pixel (so +/- 0.4% intensity), you won't achieve better than 12.5% compression.

beagle3 11y ago

Yes, and this was all the rage in the late '80s and early '90s. Everyone was sure this will replace JPEGs. See http://www.cs.northwestern.edu/~agupta/_projects/image_processing/web/FractalImageCompression/ http://www.cs.northwestern.edu/~agupta/_projects/image_proce... for a description. Spoiler: It didn't happen. Fractal compression mostly matched JPEG on rate/quality ; it didn't improve on it, though; and it was horrible in both memory use, run time, and memory requirements compared to JPEG. So JPEG it (still) is. Another Spoiler: If file size was the criterion, BPG would be replacing JPEG these days. That isn't happening either.