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-   -   How PsF video from the V1 is different than "p" or "F" video (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/86781-how-psf-video-v1-different-than-p-f-video.html)

Steve Mullen March 6th, 2007 11:46 PM

Quote:

Originally Posted by Bob Grant (Post 637378)
Ctl+Drag the end of the event so it's 4% longer, you've got the option of correcting the 4% pitch change in the audio.

The question of how to do this in FCP came up on the Sony Vegas forum, from memory there's 3rd party utilities to do the same thing.

"Without any hardware, just open a 25p file in Vegas. Set project properties to 24p. No sync issues, regardless of the length of the project."

Bob, are you talking about Vegas? If so, Spot's solution seems the easier way. Of course, I wasn't really asking about Vegas -- because with Vegas unable to record 25PsF back to HDV, it isn't an NLE I would recommend for R50 users who want to shoot 25p.

I was hoping there were some FCP or Premiere lurkers in R50 areas. Somebody is reading all these posts. :)

John Hewat March 7th, 2007 01:53 AM

Quote:

Originally Posted by Steve Mullen (Post 637387)
I was hoping there were some FCP or Premiere lurkers in R50 areas. Somebody is reading all these posts. :)

I am but I can't make head nor tail of any of it. Just when I think I've got this technology figured out they tell me otherwise.

Someone wrote to me that editing V1 footage shot in 25p mode in a 50i project in PPro (without AspectHD) resulted in pure 25p output. But I've read otherwise since. I don't understand a thing...

Bob Grant March 7th, 2007 02:37 AM

Quote:

Originally Posted by Steve Mullen (Post 637387)
"Without any hardware, just open a 25p file in Vegas. Set project properties to 24p. No sync issues, regardless of the length of the project."

Bob, are you talking about Vegas? If so, Spot's solution seems the easier way. Of course, I wasn't really asking about Vegas -- because with Vegas unable to record 25PsF back to HDV, it isn't an NLE I would recommend for R50 users who want to shoot 25p.

I was hoping there were some FCP or Premiere lurkers in R50 areas. Somebody is reading all these posts. :)

What difference will it make if you can or cannot record 25PsF back to tape?
If you record it back as 50i or 25PsF what comes out the HD component from your deck is exactly the same isn't it?
If you capture it back all you have to do is tell your NLE it's Progressive, hardly a difficult task, certainly not with Vegas and I'd guess with most other NLEs as well, after all we've been getting telecined film that way since day one in R50 land. I'd hazard a guess most people just process it as 50i, the only downside being any temporal FXs will come out truly interlaced, it's indeed better to tell the NLE to keep everything progressive.
You'll face the exactly same issues with 25F once it's captured for that matter.
Personally I wouldn't recommend going back to HDV anyway, one pass of HDV compression is bad enough.

Piotr Wozniacki March 7th, 2007 03:25 AM

Does any of you guys have access to an HDTV with FireWire input? Since feeding 25PsF live (before or after tape) into VCL using i.link doesn't create twitter, it'd be an interesting test!

As a side note: does any of the current, early HD/Blu-Ray DVD players have i.link outputs?

Tony Tremble March 7th, 2007 04:36 AM

Quote:

Originally Posted by John Hewat (Post 637437)
I am but I can't make head nor tail of any of it. Just when I think I've got this technology figured out they tell me otherwise.

Someone wrote to me that editing V1 footage shot in 25p mode in a 50i project in PPro (without AspectHD) resulted in pure 25p output. But I've read otherwise since. I don't understand a thing...

I am not surprised you finding it hard to follow.

If I have followed the meanderings correctly there is an inference that because the V1E is not sending a progressive flag via hdmi that HD DVD and Blu-ray players will not do it either.

There seems to be a misunderstanding of the Blu-ray specs. 25P will be supported via 50i. 25P is not listed in the specs as 25PsF is 50i and the only true progressive mode that is supported is 24P. That really is progressive encoded material and will be supported across all regions. In PAL land we'll watch BD at normal speed at last.

So how will TVs know not to deinterlace 25PsF? There are two methods, cadence detection and flags.

I am 99% certain of the facts but I have emailed a friend who is a very skilled DVD author using Scenarist. I am hoping he has some detailed knowledge of BD and will confirm what I say and give a greater insight.

TT

Piotr Wozniacki March 7th, 2007 04:47 AM

Quote:

Originally Posted by Tony Tremble (Post 637463)
There seems to be a misunderstanding of the Blu-ray specs. 25P will be supported via 50i. 25P is not listed in the specs as 25PsF is 50i and the only true progressive mode that is supported is 24P. That really is progressive encoded material and will be supported across all regions. In PAL land we'll watch BD at normal speed at last.

So how will TVs know not to deinterlace 25PsF? There are two methods, cadence detection and flags.

I am 99% certain of the facts but I have emailed a friend who is a very skilled DVD author using Scenarist. I am hoping he has some detailed knowledge of BD and will confirm what I say and give a greater insight.

TT

Tony, this is a very interesting and promising assumption. Please let us know what your friend has to say! BTW, do you think that the 25F from Canon doesn't show twitter because it is correctly recognized and not de-interlaced by HDTVs, or because it has less overall aliasing (at least at the default sharpness settings, as I didn't test it with sharpness turned up)?

Bob Grant March 7th, 2007 05:35 AM

Quote:

Originally Posted by Piotr Wozniacki (Post 637465)
Tony, this is a very interesting and promising assumption. Please let us know what your friend has to say! BTW, do you think that the 25F from Canon doesn't show twitter because it is correctly recognized and not de-interlaced by HDTVs, or because it has less overall aliasing (at least at the default sharpness settings, as I didn't test it with sharpness turned up)?


If you can trust the figures from the Texas shootout the XL-H1 reads 540 lines vertical res. I doubt the Canon A1 is any higher. This would probably explain why the Canon doesn't have the same issue. I think Steve was saying the V1 reads 700+

I've just tried converting 25p to 24p using Vegas. I'm doing it the long way as this avoids any interpolation. It is covered quite well in the documantation. In brief you measure the number of frames using the ruler at 25p, change the project to 24p, move the cursor to the original frame number and ctl-Drag the end of the clip to the cursor. You've slowed down the clip as needed, no different to changing the speed on a projector.

The 24p looks every bit as good as the 25p on the Vegas preview monitor. Except I'm having no end of fun trying to render it to anything without it falling to bits on fast motion. It looks like pulldown is being added but I'm compressing frames instead of fields, the macroblocking is really bad. Need to do more research on this.

Steve Mullen March 7th, 2007 05:39 AM

Quote:

Originally Posted by Bob Grant (Post 637446)
What difference will it make if you can or cannot record 25PsF back to tape?
If you record it back as 50i or 25PsF what comes out the HD component from your deck is exactly the same isn't it?

Personally I wouldn't recommend going back to HDV anyway, one pass of HDV compression is bad enough.

Obviously one can NOT record 25p or 30p to a V1. And, I assume Piotr knows that as well. He, if I remember correctly, said he could not record a 25p TIMELINE because Vegas would not convert it to the 50i needed for recording.

There is no such thing as "HDV" compression. HDV is only the marketing name attached to one Profile/Level of MPEG-2 encoding. There is little difference between the MPEG-2 recorded to HD DVD or BD and the MPEG-2 HDV recorded back to tape.

So if you fear re-encoding to HDV you equally will fear encoding for an HD DVD or BD disc.

Same "stuff" in both cases. That's why you can take an HDV file and make an HD DVD without any re-encoding.

For the next few years it will be a lot smarter to carry an HDV camcorder and your production's tape than it will be to assume you'll find an HD DVD player waiting for you in Asia or Europe -- or even the USA.

Steve Mullen March 7th, 2007 05:53 AM

Quote:

Originally Posted by Bob Grant (Post 637475)
If you can trust the figures from the Texas shootout the XL-H1 reads 540 lines vertical res. I doubt the Canon A1 is any higher. This would probably explain why the Canon doesn't have the same issue. I think Steve was saying the V1 reads 700+

I was sent a chart. When I look at the chart -- I see lots of aliasing at 800. So I'm being more conservative when I say 700+. Horizontally it was a solid 800 -- the same as the Canon.

The shootout had an F9xx at 1000x1000 -- so the V1 really does well. In fact, if not scaled/filtered to 1440, the 3ClearVid system might offer 1000 horizontally. And, Sony just happens to have a 24Mbps version of AVCHD that records 1920x1080.

So just when we've bought all our HDV toys ...

Piotr Wozniacki March 7th, 2007 06:05 AM

Quote:

Originally Posted by Bob Grant (Post 637475)
If
The 24p looks every bit as good as the 25p on the Vegas preview monitor. Except I'm having no end of fun trying to render it to anything without it falling to bits on fast motion. It looks like pulldown is being added but I'm compressing frames instead of fields, the macroblocking is really bad. Need to do more research on this.

Same here Bob - everything looks perfect but any motion!
However, when I deliberately BOB the 24p output in VLC, and send it to my LCD via component - the twitter is still there. Probably my monitor doesn't recognize it properly, either. Of course I'm bobbing it just out of curiosity, as 24p definitely shouldn't use ANY de-interlacing.

Piotr Wozniacki March 7th, 2007 06:11 AM

Quote:

Originally Posted by Piotr Wozniacki (Post 637452)
Does any of you guys have access to an HDTV with FireWire input? Since feeding 25PsF live (before or after tape) into VCL using i.link doesn't create twitter, it'd be an interesting test!

As a side note: does any of the current, early HD/Blu-Ray DVD players have i.link outputs?

Steve, you mentioned an XBR HDTV earlier on - does it happen to have an i.link input?

Steve Mullen March 7th, 2007 06:21 AM

Piotr, I'm watch your 25p >>> 60i on HD DVD and with the Flicker filter set to MEDIUM, 99% of the twitter is gone.

But the tree bark is way too soft. (Of course the light was very soft.) So if 5 is too soft and 8 is too hard -- that leaves 6 or 7.

I can go up to MAXIMUM and have a bit of twitter, but still great detail if you use 7 or almost no twitter and good detail.

My instincts tell me 7 was chosen by Sony for a very reason. So 7 seems an obvious choice. But for a film look, you may want a softer look. Just don't use 5 or 8.

Your garage has the perfect ultra thin lines for testing. Not very many things are so thin! I guess I bet 7 will be OK for most shooting. Nothing prevents presets for NORM and presets for brick buildings, etc.

Post both when you get a sunny day.

Steve Mullen March 7th, 2007 06:23 AM

Quote:

Originally Posted by Piotr Wozniacki (Post 637484)
Steve, you mentioned an XBR HDTV earlier on - does it happen to have an i.link input?

Sony made an XBR about 3 years ago I almost bought because it had an i.LINK. I think Sony has switched to HDMI for better copy protection.

Piotr Wozniacki March 7th, 2007 06:33 AM

Quote:

Originally Posted by Steve Mullen (Post 637486)
Your garage has the perfect ultra thin lines for testing. Not very many things are so thin! I guess I bet 7 will be OK for most shooting. Nothing prevents presets for NORM and presets for brick buildings, etc.

Post both when you get a sunny day.

Yes, I've chosen these fine lines on the garage wall deliberately:)
I'll be posting raw clips with S=6 and 7 at the first opportunity.

Piotr Wozniacki March 7th, 2007 08:53 AM

Here is a clip with sharpness 6:

http://rapidshare.com/files/19857440/25p_s_6.m2t

And here - the same fine lines on the garage, but with sharpness set at 7:

http://rapidshare.com/files/19857444/25p_s_7.m2t

Guys, I'll repeat my question from another topic here, as I'm about to order my gear for the V1: does the Manfrotto MN523Pro lanc controller wotk flawlessly with the V1/FX7? Thanks!


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