SDR to HDR

[Stephen!]

Potentially a cheaper way to get HD Deep Space Nine and Voyager
https://arstechnica.co.uk/information-technology/2017/05/sdr-to-hdr-conversion/

Researchers at the French research institute Bcom, with the aid of a wunderkind plucked from a nearby university, have developed software that converts existing SDR (standard dynamic range) video into HDR (high dynamic range) video. That is, the software can take almost all of the colour video content produced by humanity over the last 80 years and widen its dynamic range, increasing the brightness, contrast ratio, and number of colours displayed on-screen. I've seen the software in action and interrogated the algorithm, and I'm somewhat surprised to report how good the content looks with an expanded dynamic range.

But garbage in, garbage out, right? You can't magically create more detail (or more colour data) in an image. Well, you can—Google produced detailed face images from pixellated source images—but philosophically it is no longer the same image. When a film is cropped for TV broadcast, or you receive a blocky low-bitrate stream from Netflix, or Flickr changes the JPEG profile on an uploaded photo... are those the same image as the artist/director/videographer intended? Or are they different?

Does it even matter? If you're a broadcaster with a ton of archived SDR footage and millions of colour-thirsty potential customers who might pay for a special HDR channel, surely the only question is whether it's technically possible to convert SDR content to HDR, and whether that converted footage is subjectively enjoyable to viewers. Remaining objectively faithful to the original is just an added bonus.

 

[Santaman]

Quite interesting.. could help to bring back a lot of old material then.

 

[Timby]

Potentially a cheaper way to get HD Deep Space Nine and Voyager

Not if you actually read the article. SDR and HDR have to do with color range, not image resolution.

 

[Asbo Zaprudder]

^Yup. I've occasionally wondered if it would be possible to use Maximum Entropy analysis to increase the resolution from SD to HD. Each resulting output frame would effectively be rendered under the constraint that it is the most random image that is consistent with the information in the source frame image. The technique was used with Hubble image data before the faulty optics were replaced.

 

[Qonundrum]

Potentially a cheaper way to get HD Deep Space Nine and Voyager
https://arstechnica.co.uk/information-technology/2017/05/sdr-to-hdr-conversion/

An artificial altering of the histogram. It's a waste of time. "PowerDVD" and other media players for discs or, worse, streaming, already alter the color and more, have for years now, and it's way too easy to see crushed blacks and blooming whites, though the color levels in between do look phenomenal.

Still can't add real resolution in upscaling, though. And, related to that, it is easier to go from a true HD source and remove detail. It's harder to add authentic detail to SD sources.

I'm so glad they didn't use screencaps featuring red stripes. Color bleed would only be given unwanted emphasis with some of the algorithms used...

It's just another bait'n'switch gimmick while the sucker, I mean the customer, pays more for less.

Oh, I wrote all this before looking at the screencap comparisons. White bloom is all over the place for the girl's shiny outfit.

Then I read the headline. Do readers enjoy being insulted? (There is no conjuring or magic, nor is the advertisement process even remotely new. Nor is contrast created or conjured, the palette is merely being shifted. If it were being created you wouldn't have blooming or crushing whatsoever and the pictures are a dead and instant giveaway.)

 

[Qonundrum]

^Yup. I've occasionally wondered if it would be possible to use Maximum Entropy analysis to increase the resolution from SD to HD. Each resulting output frame would effectively be rendered under the constraint that it is the most random image that is consistent with the information in the source frame image. The technique was used with Hubble image data before the faulty optics were replaced.

Never mind interlacing, which starts to look bad on monitors larger than 20". Going from 480i to 1080P can be bad enough and some sets do a worse job than others in conversion, try 480i to 2160P on a 70" screen, of which one has to be 4 feet away to see the changes in detail compared to 1080P (those distance calculators show how pointless 4K is for residential homes despite the technology being pushed pushed pushed like a baby after 10 months). But deinterlacing is summed up nimbly with a four letter word:

Y - U - C - K.

 

[Timby]

Then I read the headline. Do readers enjoy being insulted?

Ars UK publishes something incredibly stupid, sky blue, water wet.