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Playback problem with DVCProHD 720/30pN footage
I captured the footage in DVCProHD 720/30pN to my HPX-170. Imported P2 files into CS5 project with sequence preset: DVCProHD 720/60 hz and adjusted timebase to 29.97fps (no fields/960X720/1.33 pixel ratio)
The playback is terrible with a lot of vertical striping (jaggies-like interlacing but vertical). Worst during playback-sharpens a bit when paused but still much more than I am used to with DVCPROHD footage.
This is a new machine as I recently change employers – I also have some 720/24pN footage that looked beautiful my old machine, and when imported to this one has the same vertical striping.
I was inclined to think it is simply a playback issue, but when I encoded a small clip to H.264 (720p HD high Q setting) and played in VLC and WMP, the striping is still there?
https://www.youtube.com/watch?v=RqaihpllId4
Could this be an issue with my monitor or machine? Premiere settings?
New machine specs:
HP z600 workstation
xeon e5620 2.4ghz quad with hyperthreading enabled to 8 effective cores
12 gig ddr3 ram
nvidia quadro fx 3800 (mercury playback is enabled in premiere)
samsung 7200 sata (no raid) for media files
seagate barracuda 7200 for os
viewsonic va2431 monitor -
9 Replies
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Interpreted footage and conformed to lower field first…then re-encoded with fields set to none(progressive):
https://www.youtube.com/watch?v=cG-MOBY32d8
Does this mean that DVCProHD 720/30pN is considered interlaced by Premiere? Is it also embedded in a 60i stream and therefore normal to interpret it as interlaced? Or does this mean the footage was not correctly captured as 720/30pN?
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Typically 720p30 PN footage should work on a p60 sequence without any customization…
I can’t really see what you’re referring to in the YouTube clip, but 720p is not interlaced. Are you having it interlace when you export to SD? I’d try to keep it progressive, right down to exporting it, even to SD.
TimK,
Director, Consultant
Kolb Productions, -
Thanks for the reply.
In the first clip, I kept it progressive all the way through, yet when exported to h.264 720p 29.97, the result has jaggies typical of interlaced footage.
The strange thing is, when I interpret the footage in Premiere and conform to lower fields first interlaced, then export the exact same way (720p 29.97 h.264) the result looks fine (2nd clip).
I can’t figure out an explanation. It seems to be working–but I know something is off when I have to interpret footage that I know is progressive as interlaced.
Could it be some kind of glitch in Premiere?
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I don’t know what “glitch” would be there. I worked with 720p30 PN footage for a good part of my PPro training, and it was like clockwork on Windows and Mac…
What exactly did you customize on the sequence setting…and can you simply make a new, unaltered DVCProHD 72-p60 sequence and copy/paste the content over and try it progressive all the way from there?
TimK,
Director, Consultant
Kolb Productions, -
I created a new project with the DVCProHD 720/60p preset. Left timebase at 59.97. Footage looks fine and exports fine (frames are doubled in the timeline).
The problem seems to occur when I change the timebase to 29.97. In that sequence, the footage looks terrible – appears interlaced – and exports the same.
I can’t understand why this would be happening. With 720/30pN footage, the correct timebase should be 29.97, right? Why would changing this setting make the footage appear interlaced? Very confused.
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Yeah…you can specify the framerate in the output file so it isn’t like you’re restricted to using 60fps in your H264 file.
I think most of the issue is that 720p really only has two framerates as a “video” standard…50 and 60 progressive. Panasonic’s PN modes are great as you don’t waste all the space for redundant frames (you save 50% with 30PN, but guys shooting 23.976PN save 60%…which is even more significant obviously). However, I think most systems are simply looking for that standard 720p video stream, particularly when it comes down to 30 vs 60 or 25 vs 50.
PPro understands it, so it’s not like you’re “recreating” wasted data…it’s just traveling down the pipe the way the next process expects to see it.
I suspect if there is a “glitch”, it’s likely that the “29.97” frame rate flag simply triggered the material to be read as standard def interlaced because there is no 29.97 framerate below 1920×1080 other than standard definition, which is typically interlaced. Hence the decoder probably goes through a sequence of assessment like: Q: framerate? A: 29.97, Q: Framesize 1920×1080? A: no, Choose: NTSC interlace SD decode parameters.
There was a similar hangup back when 24p/29.97i DV in the Panasonic DVX camera came out. You made a “24p” project and ended up with PAL diagnostics (waveform/vector) as it was a “framerate below 29.97 equals PAL” sort of instruction set. It was the first time that framerate was really addressed and it simply took some time to track down all the affected parameters.
TimK,
Director, Consultant
Kolb Productions, -
Interesting…thanks for the info, Tim.
I just installed CS5 on this machine and haven’t installed the update yet..perhaps it was one of the supposed P2 fixes?
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Hi Gregg et all,
I recently upgraded to PP CS5 at work and have started having the same issue with my P2 24PN footage- they all look exactly like your first youtube clip with lines and jaggies. I am not sure exactly what else to try- I am working with a DVCPRO HD 24p timebase. The clips are showing up as 23.976 … I am thinking this is a bug, because I never had a problem in CS4. Can anyone else validate this?
I am a FCP user, and totally new to Premiere, so there could very possibly be something I am missing. Did you ever resolve this, Gregg?
Thanks for your time,
~Alli~ -
The problem was corrected after installing the 5.0.3 update. The jaggies are still present when I view the footage in the source monitor panel…but the program monitor looks fine and, most importantly, the footage looks fine upon export.
If you just installed CS5 and have not updated yet – I would recommend doing so now.
Hope this helps.
-G
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