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22nd September 2015, 16:15 | #42 | Link |
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@kolak
You may want to check out this: http://rationalqm.us/dgpulldown/dgpulldown.html The 13 step cadence has been discussed somewhere along this thread: http://forum.doom9.org/showthread.php?s=&threadid=88031 which finally lead to the development of the DGpulldown tool. |
22nd September 2015, 16:18 | #44 | Link | |
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My last question is about scene changes- can it create bad scene cuts? |
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22nd September 2015, 16:50 | #47 | Link |
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Perhaps you can get more help when you post in Donald Graft's (DG...) forum:
http://rationalqm.us/board/index.php |
22nd September 2015, 17:01 | #48 | Link | |
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The collective wisdom of the engineers who designed both the original NTSC standard, and then the different set of engineers who designed our current set of international digital standards beats my knowledge of the subject, and also trumps everyone else in this forum. They understand the broad scope of all the engineering tradeoffs far better than anyone here. As for 4K not hitting the limit of human visual resolution, that is a perfect example of the narrow filter being used to make such statements. It completely fails to take into account the most important element in any discussion of resolution, which of course is screen size. I spent a decade in the desktop publishing revolution, and in the print world, resolution is usually expressed in dots per inch or lines per inch, not in terms of total pixel count. When talking about video, DPI is seldom used, but for this discussion it is a more important measure than pixel count. Why? Well, as an obvious and irrefutable example, 4K video on a hand-held device will be indistinguishable from even 720p because the human eye cannot see the difference when all those dots are crammed together in a small space. This continues to be true even as you go to larger displays like small (13 "- 19") TV sets and computer displays. However, when you get to the lower end of current "big screen" TVs, let's say 55" diagonal size, you begin to see differences, but they are subtle. As you watch on displays larger than that, most people will begin to see the differences. So, when the discussion is about 4K vs. 1920x1080 (interlaced or progressive), the spatial differences don't really become apparent or important, until you get to pretty big displays, and therefore 4K really is not important -- and never will be important -- unless the customer is watching on a really large display. We've had this discussion over at the Sony forum, and the general consensus there is that, for display in the home, 4K is not going to be a big deal, but that it is a fantastic acquisition format, and that it is also a major innovation for theatrical projection. Having been to many 4K demonstrations, I completely agree: on small screens, it is not compelling, and in fact, no one tell the difference. We can debate at what screen size the difference becomes important, but I don't have any good, objective measure to offer to help define that. My general sense is that under ideal conditions, you can begin to see a difference at around 45" displays, but for most people (and that is key when talking about market size and commercial viability), the difference won't be important until you get to much larger displays. Oh yes, seating distance from the display is also important. Finally, the whole issue of interlacing comes up because the human brain really can tell a difference -- and it is not a subtle difference -- between 24 temporal events per second and 60 temporal events per second. As has already been mentioned, it is not as fun to watch sports at 24p or even 30p, as ESPN streams on the web. Therefore there is a lot of incentive to design a system that can transmit and display 60 temporal events per second, but at a price that most people can afford, and with technology that can actually be mass-produced. I really do not understand the hostile tone in so many of these posts. We have some great choices in how we acquire our own video, and 60p 1920x1080 is easily available to everyone, so if you don't like some of the other standards, you don't ever have to deal with them. You can also easily get 4K camcorders. Use those and be happy. Finally, the people here in this forum who seem to "hate" interlacing also claim to never watch TV. I am truly puzzled as to why they even care about something that they don't have to deal with. |
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22nd September 2015, 17:12 | #49 | Link |
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As others have said, there is no "magic" pattern that is going to be better. If you want to reduce the problem, you can do what the "pros" have been doing for years, which is to change the playback speed of the original, without altering the frame at all, and then do your pulldown on that. This has been suggested in many other similar threads in this forum, but I don't think it has been mentioned here (I may have missed it). What you do is use assumefps(24) to change the playback speed, and then apply a standard 3:2 pulldown what results from that. You then adjust the audio speed, without changing pitch. I do that in Vegas, but others may know of a way to do it in AVISynth. Yes, the result will play a little slower, but that "artifact" may be more agreeable to you than the judder you get from pulldown needed to go from 25p.
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22nd September 2015, 17:25 | #50 | Link | |
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To change audio speed and/or pitch, I use Hybrid (which uses Sox for audio changes) ; http://forum.doom9.org/showthread.php?t=153035 |
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22nd September 2015, 17:28 | #51 | Link | |
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22nd September 2015, 17:42 | #53 | Link | |
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I'm not looking for "other" ideas (I know all of the possibilities), but strictly asking for pulldown method. |
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22nd September 2015, 17:48 | #54 | Link | |
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Far as I can tell, feisty2 is the only person in this thread claiming that 24 fps is good enough. I think everyone else agrees that having 60 pictures per second allows for far more fluid motion than just 24 or 30. This is so far off base I don't even know how to reply to this, but lol, you tried.
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22nd September 2015, 18:30 | #55 | Link | |
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Sorry for trying to help. Last edited by johnmeyer; 22nd September 2015 at 18:45. |
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22nd September 2015, 18:43 | #56 | Link | ||
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So, actually, not off base at all. Also, if I wanted to spend the time, I could keep going and show you the posts where people imply that they don't watch "regular" TV very often. Last edited by johnmeyer; 22nd September 2015 at 18:46. |
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22nd September 2015, 18:51 | #57 | Link | ||
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"Broadcasters are still using interlacing so it must be a good thing" is really shaky logic. They seem to want rid of it just as much as everyone else. Interlacing was a brilliant idea when it was conceived, but without it the entire broadcasting chain would be much more efficient. |
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22nd September 2015, 19:03 | #58 | Link | |
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https://www.svp-team.com/wiki/Plugins:_SVPflow |
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22nd September 2015, 19:31 | #59 | Link | |
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Say no to AviSynth 2.5.8 and DirectShowSource! Last edited by colours; 22nd September 2015 at 20:37. Reason: being nice is for suckers or something |
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22nd September 2015, 19:59 | #60 | Link | |
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What IS in dispute is whether either broadcast TV or DBS (e.g., DirecTV), within the spectrum they are allocated, have the bandwidth to do that and still offer the same number of channels. I think we could all make the argument that 80% of the channels could be eliminated, but there are strong business reasons that push broadcasters in the other direction. So, even today, 1080i is being used in order to provide a "temporally pleasing" experience, without consuming too much bandwidth. One other point that is obvious, but bears repeating, is that our current North American HD standard was finalized in 1993. That was the same year that the Intel Pentium processor was introduced, but almost all sales that year were 486 computers. Think of the truly unbelievable increase in computing power in that time. As this chart shows: Instructions Per Second the processing power these engineers had to work with was around 25 MIPS at 66 MHz.. In actuality, it was considerably less than that because consumer electronics have to sell for a low price, and the "horsepower" shown in these charts was out of that price range. In 1996, the year before the DVD (an SD device) was introduced, the Pentium Pro got us to 541 MIPS at 200 MHz. By the time the first consumer HD players arrived in stores (2004) Intel architecture chips were around 10,000 MIPS at 3 GHz. Today, Intel i7 chips at over 100,000 MIPS at over 3 GHz. The point is that many things that we can easily do today, were not even conceivable when these standards were developed. So, "change the standards!!" you say. Unfortunately, standards cannot be changed quickly. The best example of that is the changeover from SD to HD. In this country, that happened exactly seven years ago this month. Despite that time, and despite a mandate from Congress, we still have a sizeable number of channels broadcasting in SD (about 100 on my system). |
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