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iPhone camera app replaces person’s head with a leaf in photo

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Re: iPhone camera app replaces person’s head with a leaf in photo

#241
post #100

Earlier quoted context omitted.

You can set Apple's devices to shoot RAW, and it's usually pretty great, without the painting-like qualities of its default image processing.

RAW just means uncompressed, unlike JPEG or HEIF. You can still manipulate a RAW image.

>RAW just means uncompressed

This is not accurate.

https://en.wikipedia.org/wiki/Raw_image_format

Re: iPhone camera app replaces person’s head with a leaf in photo

#242

Earlier quoted context omitted.

On Android you can enable a "raw" mode that will capture a dng file with much less processing. You can then adjust that raw file and render it to a jpeg according to your taste. The dng will still have things like stabilization and multi-frame merging, but without those the image will almost always look horrible as others have explained.

RAW is not quite what they want (I think). It's HDR+ that they need to disable. The latter takes multiple frames at different exposures and smartly merged them into a single photo, then applies extra color corrections on top. Taking RAW skips the last step, but you still get a merging of multiple frames. Disabling HDR+ will, I believe, take a single frame. Of course on a small phone sensor, the quality will be quite…

Yeah I work on HDR+. Depends on the phone though, only certain phones run full HDR+, but they all do some sort of multi frame processing.

If you were able to disable HDR+ and get a single captured frame, it would look horrible. You'd have to merge multiple frames yourself to get something decent. You can Google around for ways to do that but it will only work on a few phones.

Re: iPhone camera app replaces person’s head with a leaf in photo

#243

Earlier quoted context omitted.

OK sure but the distribution of natural images is highly redundant ie pixels are not independent and there is structure to exploit. It's not magic obviously but done properly it's a pretty reasonable thing

> OK sure but the distribution of natural images is highly redundant ie pixels are not independent and there is structure to exploit. Sure, but that depends very strongly on the number of natural images you trained on and the specificity of the situation you present to the algorithm. Maybe one such structure in the training set just happens to be people holding knives given "a specific skin color and a turquoise slee…

I said if done properly. My point is that in principle using a natural image prior to 'enhance' an image is not a totally crazy thing.

Re: iPhone camera app replaces person’s head with a leaf in photo

#244

My wife's phone produced some odd results. We went out shooting Christmas decorations around town at night... The next day when we were looking at them they appeared very much like daytime photos. WTH

The phone will take a lot of shots at different exposure levels and combine them. It lets you take shots at night without having lights overexposed and the background underexposed.

Re: iPhone camera app replaces person’s head with a leaf in photo

#246
post #200

Earlier quoted context omitted.

> the Rittenhouse trial and the big to do about the video being enhanced when zoomed I keep thinking about this, and was already when the case was going on. If linear interpolated zoom isn't allowed, no iPhone photo after a certain time should be.

If linear interpolated zoom isn't allowed... Think about analog/optical/chemical photography. In the old days did juries look at camera negatives with a loupe? Of course not, they looked at enlargements. What "algorithm" does an optical enlarger use?

Continuously linear implemented with an analog device vs digital “linear” (ie, watch your floats! Take care of quanization error! Have you kept the colors separated according to the Beyer pattern?).

No one has a problem with a mathematically perfect linear transformation, and film enlargers come very close to that ideal (yes they distort, but in a very obvious way and by degrading detail not adding detail that isn't there)

The analog picture is much harder doctor. More gracious artifacts in blow up (grains are random, versus sharp grid). Much more detail is recorded (by virtue of the size of the sensor and therefore the diffraction limit. Sensor resolution is not too useful).

Re: iPhone camera app replaces person’s head with a leaf in photo

#247
post #20

Earlier quoted context omitted.

Yes, yes really. When real resolution is being substituted with the best guess of a completely closed source image processor, the court should be made aware of it.

This sounds like a weird rationalization for an absurd case of technical ignorance. Like when people defended nuking hurricanes or using UV lights as a Covid therapy.

Both sides have a right to question evidence.

Defending the suitability of evidence is the duty of re council who introduced it.

The prosecution couldn't explain how the iPhone zooms and it was on them to do so.

Btw, the prosecution later on were caught tampering with evidence.

Re: iPhone camera app replaces person’s head with a leaf in photo

#250
post #83

Earlier quoted context omitted.

I hate motion interpolation with a burning passion and have made it into practically a vendetta and will turn it off anywhere I see it by any means necessary, including downloading a remote application onto my phone and using the IR blaster to turn it off in restaurants and waking up in the middle of the night at friends houses to sneakily switch it off.

For whoever what motion interpolation is also known as is the soap opera effect on movies and I agree, it looks terrible but most people don’t get it, it doesn’t bother them at all.

According to some neuroscience article that was posted in HN recently, some people might percieve reality in "less FPS." Not only that, but as people age, the speed also goes down. Most people I know cannot discern the difference between heavy motion interpolation and it being off. In the same way, I remember when people weren't able to discern between DVD and BluRay quality in 1080p displays. Even today, many people can't see the difference between a Retina display and a 1080p monitor, which blows my mind.
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