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That I cannot explain. By my understanding 'bob' is simply interpolating one field, it might be doing something more complex than just line doubling. Also if you're watching it on anything connected to a PC there could possibly be something going on between the refresh rate of the display and the frame rate. I've see frames torn in half by this so maybe, just maybe that has some bearing on the problem.
When I get a chance I'll generate some HD test patterns using Vegas and see how they display. |
Looks like 1080/25p is not here yet -- or not coming. I found these comments:
"HD DVD discs containing high definition content at a field rate of 50Hz or a frame rate of 25Hz cannot be played on HD-XE1 without a firmware update. Firmware update is expected in the future." "Rightly or wrongly, this whole area is IMO being driven not by the broadcasters, not by the drama producers, but Hollywood. There is a major push for all the hollywood content to be delivered anywhere in the world in HD at 24p. Major political battle, broadcasters in 50 land are not happy, but Hollywood does not like the just speed it up to 25p with the Resulting audio issues. This has driven the HD display device spec to mandate that all the devices need to support 60 based support. Where people want this to go is just as now in SD you have 100hz tv's to eventually get to 120 displays. Canal for instance in Europe is going to deliver all its HD dvd's at 24p." It looks like 720p is not going to be much used, either. In last month's HDV@Work I talk about the push to "Full HD." The world is going to 1920x1080/24p/50p/60p. From cameras through HDTV. In addition, the move is 24p displayed AT 24p or 48P or 72P -- no pulldown. So it looks like the only way to show 25p is via a computer and VLC. Given how good BLEND and MEAN look -- this almost solves the problem. Unless you want to use your HDV camcorder to play your videos. Then you'll need to cut V. flicker in your NLE. But that means you need to find a way to get 25PsF out of your NLEs and into your V1 and to tape. And a way to get 25PsF into your NLE. I had to convert 25p .m2t into Apple's AIC 1080p25 .mov -- or -- 1080p25 HDV .m2v to even get it into FCP. |
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A blu ray/HD DVD player will simply signal to your HDTV that the content is progressive so don't deinterlace. It would appear either the V1 does not output the desired signal or the TV/monitors you've connected it to don't acknowledge the signal from the V1 causing the deinterlacing errors. Mikko answered this issue several posts ago. Perhaps the answer was too obvious? TT |
1) converted Piotr's test clip using MPEGStreamclip to Apple's 1080p25 HDV codec.
2) playing both original and converted in MPEGStreamclip one could see the line-twitter using S=7. I did this to check if the conversion might filter the original. It didn't. 3) imported the 1080p25 clip 4 times into 1080p25 FCP Sequence, added 3 levels of Flicker Filter, and made a 1080p25 HDV movie. 4) played movie in QTplayer via HDMI to my HDTV. There was no line-twitter. EVEN ON THE CLIP WITH NO FILTER. 5) Played Source clip and Sequence in FCP. Again -- no line-twitter on anything. If I had a V1E and used FCP -- and I had never read about the V1E's "problems" -- I would see nothing wrong even if I used S=7! So I used VLC to play the original clip. Very consistent results: if I turned on bob deinterlace, I had line-twitter except at S=3. If I used Blend or Mean, I did not even at S=7. Then I remembered TT claiming he watched 25p without deinterlacing. I assumed he was using a CRT HDTV. He said he wasn't -- he was using VLC. So if he wasn't using deinterlace, that likely means he was running VLC with deinterlace DISABLED. So I switched to disabled and there was no line-twitter even at S=7. VLC with deinterlace DISABLED plays just like FCP and the QTplayer -- there's no aliasing or line-twitter even with S=7. THEN I REMEMBERED THAT the clip I had was a movie -- not original V1E video. Piotr's test clip is 1080/25p. That means -- I assume -- that Premiere took the 2 fields within 50i and put them into 1 frame and changed the frame rate to 25 and set the P flag. So it makes perfect sense that DISABLED is the correct way to play a 25p MOVIE. And, the QTplayer and FCP seem to do the same. So the production cycle of 25PsF to 25P seems to fix the problem and there is no need -- if you are making a 25p MOVIE -- to use S=3. ---------------- But note something else -- how you play video determines what you see. Even with true 25p, I could make the problem come and go just by WHICH software I used and WHAT setting I used. Piotr -- can you upload a 25p S=7 mode captured directly from the camera. |
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And although Vegas doesn't have a 25p template I can quite easily render 1080 25p from the V1P's 25PsF. And the interesting thing about BD and 1080p. Well HD DVD does do 1080p, they've tried using that as a selling point but Sony themselves keep say it's all smoke and mirrors stuff as it all ends up the same when it's displayed. As for the rest of the comments about display devices affecting how an image look, well duh. Just because it looks fine on some devices doesn't mean there's no fault in what being fed to the device that shows a problem, usually the reverse in fact. Get the field order reversed with 50i and it still looks fine on LCDs, are you suggesting the fault is in our broadcast CRTs? Get one channel of dual mono audio out of phase and it still sounds OK on the stereo monitors but totally vanishes on my mono TV. Ah I get it, it's there's nothing wrong with my audio just the silly viewer for having a mono TV, silly them. So far the most credible explaination of where the problems lies was a deduction from a comment by Adam Wilt about Sony allowing too much res compared to Canon at the expense of aliasing. Possibly the OLPF is set too high. Why would Sony do that, well this camera takes still through the same lens and imagers, perhaps they didn't want to loose res when stills were being taken. |
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Vegas doesn't have a 25p template simply because one wasn't made. If you have the VASST GearShift tool, you *do* have a 25p template, as we install one. In other words, just make one. As Bob mentioned, all that you need is there. Speaking of Bob, great post! Looking forward to seeing you at NAB and this winter in Oz. |
Douglas, of course I have made my own 25p templates in Vegas (actually the clips I'm posting to this thread were all rendered in Vegas, not in Premiere as Steve is assuming). But the fact is such a template has NOT been included with the system (the "Blue Print" ones are only 50i, 60i and 24p - just like in the Blu-Ray Disk specification). And this cannot be just a coincidence or ommision, IMO.
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Anyway, here is the first one: http://rapidshare.com/files/19374454...g_shrp_8-2.m2t (sharpness 8) more are coming (with sharpness at 10 and 12). http://rapidshare.com/files/19379721...og_shrp_10.m2t http://rapidshare.com/files/19393514...og_shrp_12.m2t |
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Also, the peculiarities of the V1E's progressive mode (in how aliasing prone it is) have forced me to discover various Vegas settings and tricks that I never paid attention to before, as with the Canon A1 they didn't make much difference. Firstly, you can create a new project using the usual 1080/50i template with upper field first, but changing deiterlace mode to "blend fields". Conversely, you can use the "None" (progressive scan) field order, and - even though it doesn't sound logical - also choose "blend fields" as Deinterlace method. Secondly, you can add a slight vertical Gaussian Blur (though even the smallest possible of 0.001 results in too much softening IMO), or set the option "reduce interlace flicker" in the clips properties, which seems to do the trick. Then, the rendering of a 1080/25p output MPEG-2 file. I must say I don't quite understand why we have the options of deinterlacing methods when creating a new project, but NOT when creating progressive file from an interlaced source; in the "render as" template you can only set Fieldd order (upper first, lower first, or progressive). Hmmm. Add to it the various options at playback time (like using Blend in VLC), and you get a headache when trying to established an optimal workflow for the 25PfS of the V1E. It'd be much easier if a more comprehensive description of all the Vegas options involved was available, because the manual and help system don't seem to be very specific. Here a kind request to Steve and DSE: could you please help us the PAL V1 users with the above? TIA! |
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"And the interesting thing about BD and 1080p. Well HD DVD does do 1080p" HD DVD supports 1080/50P and 1080/60P output. The high-end Toshiba cannot even do 1080/24P output let alone 108025P output. In terms of recording, only 24p, 50i, and 50i are supported. ", they've tried using that as a selling point but Sony themselves keep say it's all smoke and mirrors stuff as it all ends up the same when it's displayed." Sony can say that about 24p because you'll remember I posted earlier that 24p was the only frame-rate that POTENTIALLY could be perfectly deinterlaced in your HDTV. So yes, 1080i60 can carry 24p. Unfortunately, tests indicate it often does work pefectly -- which is why the demand for 60P output -- and for 24p OUPUT. "Just because it looks fine on some devices doesn't mean there's no fault in what being fed to the device that shows a problem, usually the reverse in fact." An obviously true statement. So obvious that I see no point to it the context of this discussion. The goal NOW is to find a way to produce P movies from 25p V1E video that look good. If that can be done, the question of what to blame becomes moot. |
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The progressive formats are 720p50 and 720p60 and 1080p24. The interlace formats are: 1060i50 and 1080i60. You can shoot 720p25, 720p30, and 1080p25 but most NLEs do not support anything but 720p30 and 1080p25. At this point in time -- the two hidef DVD formats support only: 1080p24, 720p60, and 1080i60. Other than the crazy expensive BD software, software supports the burning of only 720p60 and 1080i60. I have burned 720p30 by tricking the software into thinking it was 720p60. I have yet to try 24p with pulldown within 720p60 and 1080i60. Which means you can make 1080p25 and play it with VLC -- or you can try exporting your 25p timeline as 1080i50. This should be able to be burned to red laser discs and played on a hidef DVD. However, because the software is all written in R60 areas, and mostly for use by folks burning copies of HDTV programs, it may not yet support 1080i50. Thank you for the S=8. Playing original with VLC/MPEGstream and FCP clip shows bad line-twitter. After making a 1080p25 HDV movie and playing using QTplayer -- even the original clip (no filter) looks very good. The filter helps, but not much. Upload S=5 and S= 7 -- these may be safer bets. |
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Heck, I reallly don't understand why such a good video cannot be played on a Sony Bravia through state-of-the-art interface (HDMI) without line twittering so horrible that it is unwatchable. If only I could be certain that a method can be worked out of creating HD DVD and / or Blu-Ray disks that would play as clean as those software players, I would already be able to make up my mind and stay with the V1... |
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1) You can use S=8 which is very nicely detailed. (A bit too much -- I would use 6 or 7.) There is NO need to set S=3. The S=3 recommendation was based on viewing the camera output and/or using VLC set to bob interlace. 2) Using VLC set to NO deinterlace which is correct for PsF -- the video is fine. Even when played thru HDMI to an HDTV. 3) Working with FCP there is line twitter in the tiny FCP windows. When you connect the HDMI and the video is played thru HDMI to an HDTV -- it is fine. 4) you can make an 1080p25 HDV movie or a 1080i50 movie and play with the QTplayer thru HDMI to an HDTV -- both are fine. Bottom line -- in actual production the V1 works perfectly with 25p at S=8. And, any movie one makes also looks fine. -------------- That leaves 2 open questions: 1) why does S=8 look so bad connected when played from the camcorder direct to a monitor. I see only 2 possibilities: a) The crap is actually in the V1 recording. b) The monitor is creating the crap. The experiments we have done -- and everyone is free to try them -- says the crap appears and disappears based on the de-interlace setting in VLC. Bob would MIGHT claim the crap is in the recording and the VLC setting only changes whether we show it or filter it out. I MIGHT claim the crap is NOT in the recording and the VLC setting only changes whether we create it or show the V1 video correctly. I don't think we'll easily prove which is correct. The question I think we can answer is -- can the V1 be used to make movies. With FCP and playing from a computer to an HDTV, the answer is yes. It seems you can do the same with Vegas, so you answer is double yes. So now the question becomes how will you "record" your production IN HD. Here the answers are: 1) you cannot now record 1080p25 to any hidef disc. You may never be able to do it if players don't support it. 2) you could convert to 24p. 3) you could export to 1080i50 and burn it. I can help you with this. 4) you could export it back to the camera. This is the test you can do the quickest. You can't print-to-tape from a 25p timeline. You would need to export a 50i movie, import it to a 50i timeline, and print-to-tape the 50i timeline. The V1 can only record 50i. Have you done this? Have you tried playing this on a Bravia from the V1. |
I'll stand corrected, but it seems to me that 25P is a useless format as it can only be viewed by someone with a V1P/E and a computer to a HDTV.
You can only use the V1P to view 25P shot from the camera via a NLE through HDMI to a HDTV. There is no way it can be played as a rendered movie with either Bluray or HDDVD. You cannot print to tape to store an edited movie. Converting to interlaced seems to defeat the purpose of having progressive. As well converting to 24P is desperation, why own a PAL progressive camera in the first place. If anyone can tell me I have got it wrong I would be glad to hear Michael. |
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As to how much 0.001 is I have not a clue and this is something about MANY of the FX parameters in Vegas I've had the odd complaint about over the years, there's all sort of odd numbers that bear no relationship to anything or are at best cryptic, adding some units of measure would be great. The de-interlace method is very important when rescaling and there's no optimal setting. It's important because half the resolution is in one field and half in the other. The lines may not line up so to preserve resolution and to prevent hideous aliasing (think large gear teeth, not fine combing) you need to specify a method. Blend works best for low motion, interpolate for high motion. The value specified in the project de-interlace method works accross the entire project, including rendering. As you can hopefully see even when going from 50i to 50i it has a major impact if any rescaling is taking place e.g. rendering from HDV to SD. I don't know exactly what Reduce Interlace Flicker does exactly, again it would be good to get an explaination but none has been forthcoming. It would seem to force some kind of line averaging. One thing you can do with Vegas that might help workout just what your display is doing is to deliberately reverse the field order, easy enough to do, just RClick the media and change the field order and render out. On a true progressive display it shouldn't matter, if the Bravia is attempting to display fields motion should become a mess, think Joe Cocker on hot coals. As to why there's no 25p template, well the answer I got was because there's no tape device that you can print that to. As we know you can create your own template of course. |
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Of course the goal is to find a way to deliver the best possible looking 25p by finding a way to do this. Only reason I keep pursuing the "what's causing it aspect" is not to lay blame as much as by understanding the processes involved we can better decide how to deal with it. My suggestions at this stage would be pretty much in line with what you've been saying, probably reducing Sharpness in the camera is going to be the simplest approach (the GB FX in Vegas is a render hog). If you want more control then go with either GB in Vegas or the Reduce Interlace Flicker properties switch. I'm certain other NLEs have suitable FXs. If you're truly going for a film out then ignore the problem, get as much sharpness on the tape as possible. BTW, I checked out our V1P today, PP1 (Cinema) sets Sharpness to 5 and PP2 (Portrait) sets it to 7 but ups the Skin Detail Level, is this the same in the V1U? I suspect that if you're going for broadcast then you probably really need to do something. I suspect putting this 25PsF onto a HD CRT is really going to make the aliasing very obvious, the viewers might or might not see it but the guys doing tech checks on your content most likely will. I have a small CRT HD broadcast monitor, it'll be interesting to see how the 25PsF looks on that. As an interesting aside, apart from dealing with 1,000s of hidef digital photos and their attendant aliasing problems when downscaled to SD in Vegas I've also done 5,000 slide scans at around 4K, none of them needed any treatment when downscaled for SD. It could be that these were taken with older cameras before the days of multicoated optics, it could be nature of film. |
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So while I wouldn't say 25p will always be useless -- it is looking like it might be for awhile. Except if you WANT to play it from your computer. That really works well. One thought I've had is that Sony Japan never planned a 25p version, but was convinced by Sony UK before IBC to do it. The first firmware could have been a botched attempt to have something to show at IBC. Think how quickly 25p was pulled. Then, just as quickly, they came-up with "new" firmware and the S=3 recommendation. |
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Now that I think I know what the difference may be -- I'm far more open to seeing the issue as "in" the V1E. However, before I go further down this path -- I've sent another list of questions to Japan about the MPEG-2 flags. Meantime, I've done a brute force 1080/25p to 1080/60i export via Compressor. I'll make an HD DVD. If it plays, I want to see if the line-twitter is gone or returns. |
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ad 3) above: I'm not quite clear on this; what's the point in exporting 25p to 50i rather than making 50i in the first place (or what you mean is just for testing purposes) ad 4) I'll be printing back to tape today. So, the workflow shuld be: - create a 1080/50i project and import my 25p clips - render as 1080/50i -import the MPEG-2 movie created above back to the TL - print it to tape from TL Please correct me if I'm wrong anywhere in the above workflow. Thanks! |
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I'd be interesting to see how the 25p from the F350 compares with the 25p from the V1P/E/C. Anyone know if the F350 users are having similar issues, I check the XDCAM fora from time to time and I've not noticed any. For what it's worth I do know that this is not the only camera to have 'teething' problems, the JVC HD100 had it's share although they were real and the HVX200 had a few that weren't real and from memory how users were viewing the footage was the main cause of their concerns. |
Coming back to the topic, I have just printed back to tape (BTW, when you choose in Vegas to print a ready file rather than from the time line, it is possible to print both I and P files). When played back from the camera via component, the twitter is there like in the original.
However, I noticed that when you play back from camera (live or from tape) using compressed i.link (firewire), the twitter is gone - just like when playing back from a software player (eg. VLC). Bottom line: the heavy line twitter is only present when playing back from camera using uncompressed format (from HDMI or Component). I don't think there is any point in further testing various sharpness settings, as they can only mask (when low) or emphasize (when high) the problem, which is somewhere else. All comments welcome! |
VLC does line twitter for about every video clip when you use bob. Powerdvd and/or nvidias own bob-deinterlacers do a way better job than vlc.
Line twitter in FCP can be eliminated (if working with progressive) by changing the fields in project settings to none. |
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WORKFLOW: - create a 1080/25p project and import 25p clips - add graphics and titles - render as 1080/25p for VLC playback I'm not sure how you can print a 25p Timeline to the V1? Can you simply print-to-tape from a 1080/p25 timeline? Will Vegas add the correct flags and convert it to PsF? ------------------ However, I noticed that when you play back from camera (live or from tape) using compressed i.link (firewire), the twitter is gone -- just like when playing back from a software player (eg. VLC). Bottom line: the heavy line twitter is only present when playing back from camera using uncompressed format (from HDMI or Component). HOW do you view the i.LINK signal? What do you feed the i.LINK signal into? |
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Simple example of the problem. Take an odd field of black and an even field of white. Merge them into a single frame, duplicate and render out as 25p. You've now got a frame with 1080 line of V res. It'll look fine on a real 25p display but all you get on a 50i display is a blinking screen. Thing is for 50i the max V res is half what it is for 25p otherwise line twitter will get you. Doesn't matter if the source is 25p or 50i, once it's displayed as 50i you have the problem. Hope this makes sense. |
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So what's happening with the camera analog & HDMI output? I assume it's sending out one field then the next field. Each field has only 540-lines. It is an interlaced signal which means a monitor will treat it as interlaced. Static video will have it's fields woven together (weave) into a frame and presented twice per second. No twitter. What happens with motion video is based on the monitor's deinterlacer. It might bob, or do something much better. If bob: the first field's odd lines go into a 1080-line frame. The 540 missing (even) lines are interpolated from the existing 540-lines. Now this frame is presented for 1/50th second. Then, the second field's even lines go into a 1080-line frame. The 540 missing (odd) lines are interpolated from the existing 540-lines. Now this frame is presented for 1/50th second. Herein lies the problem. Watch the top odd line: it goes from real to interpolated to real to interpolated. A thin line will fall on a single row. Assume the line falls on top of real line. The next interpolated line CANNOT have this thin line. So when you watch, every 1/50th of a second it dissappears. On and off. On and off. bob generates flicker. Hence the name bob. I'll bet if you plug the V1 into an HDTV that does not do bob the twitter will go away. There are two levels of Bravia. One is a cheap unit typically sold in Asia, etc. The S2 if I remember. Look for an XBR HDTV. I think the reason we see this only on the E/P is because the CMOS sampling rate is higher than it is for the U -- yet the chips have the same number of rows. This causes more aliasing, but also captures more V rez. hence the E/P actually records finer vertical detail. Hence, the greater possibility of very "thin" lines. If I'm correct, it is an unhappy combination of the V1's geater V. rez. plus its interlaced PsF plus a bob monitor's deinterlacer. A real bad combination. Can anyone guess why the E/P might have a CMOS sampling rate is higher than it is for the U? |
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Now I wonder if it also cannot record 30p and 24p back to the V1U. Spot? |
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Steve, what would your "bottom line" verdict on the V1E's 25PsF be, based on what we established? Your theory on why the line twitter appears (and spoils the picture) under certain conditions boil down to how the video is watched and NOT to how it's produced - do I get you right? |
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Later today I'm going to burn your 25p and play it on my hd dvd play. This would be like your using a 50i movie. lets see if the twitter stays gone. I'm heading to bed. |
Sorry Steve, my bad. Yes you can pick a progressive movie file from your HDD and print it to tape from within Vegas, but it is recorded in the interlaced format anyway.
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One can pretty easily convert 25p to 24p in Vegas without any resampling, you can do a precise frame rate conversion. There's at least one utility to do this in FCP too. As to are the bit clocks faster in the V1E. I'd suspect they might be. In SD DV they're the same 13.5MHz, the lower PAL frame rate yields more pixels in the same bps. What happens in HD where there's the same number of pixels and a different frame rate? My best guess is the bitclock runs faster and hence yields more res. |
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Thanks for your explaination of how bob works, from what I've seen on the Bravia it looks exactly like what you'd get if that's what it's doing, as you've rightly said it shouldn't be doing that, it should be weaving. Is this just a sloppy display device or is it something the camera is sending it fooling it into bobbing when it should be weaving? I need to go back and very carefully recheck this but I'm 80% certain that my 25p footage shot at 1/25th on a bright sunny day shows no twitter on the Bravia. With the camera connected directly via HDMI to the Bravia and pointed into our flat well lit office, no line twitter in 25p. Move the camera around to point at a dimly lit page with fine horizontal lines, twitter. How is the display being fooled, my best guess, noise. I should check this by simply pointing the camera at the same problematic subject and changing the light level while letting the camera raise gain. |
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Thanks for that. I'll still do the tests later this week. On this very matter though here's what has me confused. With a locked off shot, no camera or subject motion. What the camera is sending to the Bravia will be the same whether the camera is in I or P, two fields with no temporal offset. Now Steve has said the resolution is the same in I or P, OK. So why does the Bravia not display any twitter in I and yet it does in P? In theory in I a camera is supposed to employ line averaging to avoid twitter but from what Steve was saying some time ago, this camera doesn't do that. I'm not so certain this is correct. The noise levels are lower in I and the twitter is missing from the display. |
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