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Originally Posted by markfilipak
FranceBB can't mean motion vector interpolation because, if the TV is doing the decoding -- doubtful but possible -- then inside the TV at that point there's raw frames.
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TVs nowadays are like computers, they can decode and apply all kind of post-processing with a tiny delay. Particularly Samsung is known to apply all kind of processing to the image.
Quote:
Originally Posted by markfilipak
how do you know that's what the TV does? Does it tell you?
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It doesn't tell me anything, but what I see is what I also saw in the studio. For instance, if I'm watching Sky Cinema and I'm watching a movie, I know for a fact that we received it at 23.976fps and that it has been speeded up + pitch adjusted by 4% to get to 25fps and then it has been flagged as interlaced, therefore it's progressive flagged as interlaced. When I see it in a broadcast reference monitor from Sony, it clearly stutters 'cause the broadcast monitor receiving the playback from Omneon through SDI just detects the properties and bobs it to 50p ('cause all displays are progressive), however, since it's actually 25p flagged as 25i, both fields are exactly the same, therefore you end up seeing duplicated frames all over the place, hence it stutters (although that's the way it's supposed to be seen by the viewers). What happens then is that if I see that very same content after it has been aired and I receive it with my Sky Q box plugged via HDMI to the Samsung TV, such a TV will see the frame properties (i.e 25i), it will detect internally that it's actually 25p flagged as 25i and it will perform motion vector calculations to bring it to 50p.
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Originally Posted by markfilipak
Can you describe the artifacts? Are they background "drag" along the boundary of motion objects in panning shots? -- looks like the bow wave and wake of a boat viewed from overhead. That's what I sometimes get with real-time motion interpolation when the interpolator doesn't have enough time. Or by "artifacts" do you mean aliasing? Or maybe pixel twitter -- like sparkling?
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Sure. So, whenever you have a pan like a landscape etc, the interpolation is perfect 'cause motion vectors match perfectly and the newly created ones (the artificial ones from the optical flow) are indistinguishable from the real ones, so everything checks out. The problem is when there are fast changing scenes, especially with noise or dynamic grain. In that case, sometimes, you see a frame which has artifacts in some 16x16 blocks like if there are two people fighting there might be a spark in the blocks of the immediately subsequent frames even if it's not supposed to be there. Sometimes you can see things like some "dirt" on clothes like things that are not supposed to be there but that they are due to poor prediction, but you never find things as noticeable as people with 6 fingers or 3 legs etc. I mean, with time this kind of calculation has become better and better and I feel like it will only get better. On the other hand, this is pissing some content creators off a bit 'cause sometimes the choice of shooting to 25p rather than 50p (and divide in fields to get 25i) is something that the author wants and having TVs just doing what the heck they want isn't what they want.
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Originally Posted by markfilipak
Well, 28fps that actually displays at 28fps will not stutter, so your TV must be doing some sort of telecine.
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Well no, I meant that if you send a 28p signal it will not be recognized and the TV will just duplicate it to 60p, hence stuttering. By saying "displaying it as it is" I meant that it doesn't interpolate or blends and just duplicates ehehhehe
Quote:
Originally Posted by markfilipak
You're a pro!
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lol, well, I do work for Sky, yeah, but I'm not really interested in buying a new consumer TV right now as I think I'm gonna wait a bit more for when 8K is gonna be supported. Some friends of mine got "punished" for being over enthusiastic about new technologies and buying a 4K TV early on in 2013, 'cause they ended up having TVs which were able to understand BT2020 but no color curve whatsoever, hence being forced to see everything at 100 nits. Luckily I wasn't one of them, but I feel like I'm gonna wait a bit more for 8K and H.266 VVC compatibility.