The fallacy about 8bits and 10 bits

Technically-oriented discussion of classic films on everything from 35mm to Blu-Ray
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All Darc

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The fallacy about 8bits and 10 bits

PostMon Oct 30, 2017 6:39 am

Interesting how people like to be made of fools.

Now the video encoding softwares companies wants to wash their hands about the poor or sometimes mizerable color gradients on HD video, by clamming it's fall of 8 bits limitation, and that this will only be solved with 10 bit image/video. On web there are image examples side by side of what suposed would be 8 bits Vs 10 bits, with the supposed 8 bit showing a lot of banding.
But the funny thing is that both sides are the same image, a JPEG file which have 8 bits (256 tones for each color channel -red-green-blue).

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Example using two image files, for each image, but both JPEG and so both only 8 bits.

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So this talk of the need for 10 bits sounds a bit stupid, since the reason of the banding is the garbage nature of MPEG-4 for gradients and tonalities. If the old JPEG can hold fine gradients, the problem is not the 8 bits as they said.

In a similar way they did the crap talk with HDR TVS. After LCD TVs started the damn holocaust of dynamic range, with clipped whites and crushed shadows everywhere, thing that CRT TVs never did, they came with HDR screens trying to say it's a technology to better dynamics than ever, but in reality it's more to try to fix the "screw-up nature" of LCD pannels.
Keep thinking...

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fwtep

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Re: The fallacy about 8bits and 10 bits

PostMon Oct 30, 2017 2:48 pm

You are wrong. 8 bit has terrible banding, most noticeable in gradients. Since most people's monitors are 8 bit, you have to make a simulation, using dithering, to show how 10 bit can look. In the early 90s I was doing visual effects for a TV show and we had a lot of problems because everything was 8 bit. The show took place under water, so the backgrounds were all blue gradients.

Compression makes things worse, but even uncompressed 8 bit has banding issues in gradients. The images you posted DO have banding in the 10 bit versions. It's not as noticeable as the accented banding in the 8 bit versions, but it's there.
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All Darc

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Re: The fallacy about 8bits and 10 bits

PostMon Oct 30, 2017 3:14 pm

The image I posted it's JPEG, and can have little banding.
If I had said the JPEG have also banding people in this forum would have called me a fanatic perfectionist freak. :lol:
I recreate this "horizon" gradient (example 2) in Photoshop, in 8 bits, using gradient tool, and it's hard to notice banding. It's easier in gradient from black to white.

The MPEG-4 extra banding, let's call this way to be more right to you, it's a lot more banding than the uncompressed, and tends to looks like a piece of garbage during fade-in and fade-out on movies.

In sure if they create a 10 bit compression, it will screw up as always, specialy in HD broadcast (that uses real time encoding) and generate banding.

Not just the banding it's anoying, but also the fake grain, the little squares pattern we see in encoding of old color films.

For me there is no good HD video system available, since all have terrible problems with compression artefacts, even blu-rays (most have artefacts). I don't even watch HD broadcast. I just watch Youtube on small windows and almost in never full screen.
All 4K videos I downloaded and tested in a 4K TV have very noticeable artefacts and banding, including a video sample of 1,1GB for just 1minute and 30 seconds of duration.

Besides, all HD TVs I saw, LCD and LED backlight LCD, do not look good to me. All have horrible view if turn as little as 20 degree, all have blur during little motion, and all create disturbing disgustinbg white clipping and crushed shadows.
I watch films on a CRT TV. I would never accept a LCD TV even for free.

fwtep wrote:You are wrong. 8 bit has terrible banding, most noticeable in gradients. Since most people's monitors are 8 bit, you have to make a simulation, using dithering, to show how 10 bit can look. In the early 90s I was doing visual effects for a TV show and we had a lot of problems because everything was 8 bit. The show took place under water, so the backgrounds were all blue gradients.

Compression makes things worse, but even uncompressed 8 bit has banding issues in gradients. The images you posted DO have banding in the 10 bit versions. It's not as noticeable as the accented banding in the 8 bit versions, but it's there.
Keep thinking...

Image

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