I've attempted to get researchers to use lossless H.264 to encode CT scans. They typically use directories full of tiffs. Even with intra-slice compression (i.e. tiff compression) they are pretty huge. But H.264 will let you recover the original images to the individual bit, and save a huge amount of space thanks to inter-slice similarities.
I’d imagine the main drawback of using H.264 here is that you’d still have to decode to get the frames back. This is similar to how even though many consumer grade cameras will output natively to h.264, if you want to edit the videos from it you’d usually have to convert it to prores or something first (the editor would usually do this automatically behind the scenes)
I’m not sure if lossless h.264 is I only or not, but if it uses inter-frame compression then it’s difficult to randomly access arbitrary frames. For any arbitrary frame you’d have to find the nearest key frame, then interpolate from there based on the inter-frame compression metadata.
It's acceptable to use the nearest key frame when randomly accessing arbitrary frames.
The real problem is that you'd have to rewrite the entire app stack to use H.264 or AV1 for storing the image stack generated by CT.
CT images are 16-bit monochrome, and the pixel values have real physical meaning (Hounsfield Units). So you'd have to prove that your compression tool can reproduce the original images 1:1. The H.264 encoder would also need to be modified to support 16-bit pixels.
And you'd need to modify the post-processing tools to accept your new file format. Otherwise users will still have to convert it back to DICOM or some other commonly accepted format before they can use their post-processing software.
So unless you're a CT vendor, you'll have a hard time pushing this into a hospital.
'Anonymisation' schemes are a little like encryption, in that they just get monotonically weaker over time as people work out attacks. But the attacks tend to be much worse. I work in academic open data publishing, and the netflix prize (https://arxiv.org/abs/cs/0610105) hangs over our heads.
But what this illustrates to me is that researchers are just really careless, despite everything we make them agree to in data transfer agreements. It seems absurd to have little cubicles like this https://safepodnetwork.ac.uk/ (think Mission Impossible 1) but I do despair.
Then somebody needs to let the government know, because the relevant 1981 act is "[a]n Act to make fresh provision about citizenship and nationality". In that 'British subjects' are a quite limited subset of citizens. Most British people are citizens, not subjects.
My (really limited) understanding is that 'British subject' was the status of people in the British empire. It's now reduced to just some people born pre-1949 in Ireland and India. They have many of the rights of citizens, and can become citizens via a simpler route than other non-nationals.
I was 17 at the time :) And FWIW, the whole joke there was that neither me nor the other guy being interviewed had anything at all to do with the attacks on PSN and XBL.
Yes, I'm sure my comments here are just full of terribly damaging stuff.
Not sure what the theory here is. Am I supposed to worry about the judges stalking me online and reading my HN comments professing innocence?
The prosecutors couldn't, and wouldn't even want to use anything I've written here, especially considering the trial is over and they can't just file new evidence.
(I can't find the 1.1 docs, but they were the same)
It's one of my favourite examples of how languages pretty much always get date and time hopelessly wrong initially. Java now has one of the best temporal APIs.
Yeah, it effectively became a typed wrapper of a long epoch millis value. Generally treated as immutable by convention in my experience, although of course it technically wasn't as the setters were never removed.
It was hopelessly wrong initially, and got even worse when they added the horrible sql Date/Timestamp/etc classes.
With java.time though, it is the gold standard as far as I've seen.
They are still using directories of tiff, though.
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