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Old Aug 28, 2009, 4:56 PM   #11
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Originally Posted by Trevmar View Post
I just bought a Panasonic ZS3, with x12 zoom, and 60fps 720p video (please don't flame me on this - it is 60p, I have analyzed each frame with AVIsynth and Virtualdub).
Interesting as even Panasonic themselves say it's really 30fps:

1280x720, 60P(CCD output is 30p)

So I take it you actually saw differences between all the frames? I guess either Panasonic specs are wrong (although I thought I read somewhere that this was verified by Panasonic) or perhaps they are interpolating between the frames?

I have to say though, I always wondered why would only Panasonic have a sensor only capable of 30fps especially as it's not exactly an inexpensive camera!
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Old Aug 29, 2009, 12:32 AM   #12
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I am apparently the only person owning a ZS3 who uses a Cineform AVCHD workflow. Cineform takes the AVCHD lite and produces 60 progressive frames per second from it. I will do a demonstration video as soon as I can find a metronome, or something similar to photograph
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Old Aug 29, 2009, 3:20 AM   #13
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Originally Posted by Trevmar View Post
I am apparently the only person owning a ZS3 who uses a Cineform AVCHD workflow. Cineform takes the AVCHD lite and produces 60 progressive frames per second from it. I will do a demonstration video as soon as I can find a metronome, or something similar to photograph
If you're processing the clips in Cineform, then that's not the original framerate any more, is it?

Cineform may be bob-deinterlacing the footage, which results in true progressive video at twice the fieldrate. That's probably how you're getting the 60fps output. You can do the same for any 30i footage by bobbing in Avisynth.
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Old Aug 29, 2009, 10:04 AM   #14
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Cineform may be bob-deinterlacing the footage, which results in true progressive video at twice the fieldrate. That's probably how you're getting the 60fps output. You can do the same for any 30i footage by bobbing in Avisynth.
Here is what Mediainfo says about the raw file from the ZS3:
Video
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : [email protected]
Format settings, CABAC : No
Format settings, ReFrames : 1 frame
Duration : 8s 475ms
Bit rate : 12.0 Mbps
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16/9
Frame rate : 59.940 fps
Standard : NTSC
Resolution : 24 bits
Colorimetry : 4:2:0
Scan type : Progressive
Bits/(Pixel*Frame) : 0.218
Stream size : 12.2 MiB (94%)

So there shouldn't really be any interlacing at all, since the video is encoded as progressive. But you are correct, there is something in the way the AVCHD codecs are handling the video which is incorrect, or at least sub-optimal.

When I convert to Cineform, using the "Maintain Source Frame Format" option (rather than the "Pull-down to 24p for Canon" option which I normally use), then the Cineform output is a true 60p.

I have verified this by stepping through each 60p Cineform frame in Virtualdub, each frame is discrete and progressive, there is no interpolation or motion estimation (the edges of the image are clean).

Additionally, when I play the Cineform video in Media Player Classic, the panning looks much smoother than when I play the AVCHD-Lite source video in the same media player.

Really strange behavior. Apparently an artifact of AVCHD-Lite decoding by the current codecs. I will try AVIsynth with bob, as you suggest, and see what I find.
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Old Aug 29, 2009, 11:11 AM   #15
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OK. I apologize for accidentally 'calling wolf'. The output of the ZS3 is AVCHD-Lite 60fps progressive, but only every second frame is changed. The problem was in my Cineform AVCHD converter. It got confused by the input being llabeled as 60p rather than 60i.

I finally validated what was happening with AVIsynth and Virtualdub.
Following the excellent page on de-interlacing technologies by Janik at
http://www.100fps.com/
I used Gunnar Thalin's "deinterlace-smooth" to validate the input format. Gunnar's filter should have given twice the frame rate if the video had been interlaced, but it did not. The video from the ZS3 consists of 60 progressive frames arranged as groups of two.

It is clear that we will need to be very careful when importing AVCHD-Lite into editors to make sure that their de-interlacing does not get confused by the video stream being marked as "59.94 fps progressive."

Thanks to everybody for their help
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Old Aug 29, 2009, 11:59 AM   #16
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Not to devalue your meticulous attention to research but I did find it odd at first when you said it was a true 60fps and that no one else had managed to confirm this

Still it makes me wonder why they convert it to 60fps when it's rather pointless? Does the AVCHD spec only allow 60fps in the 720p format?
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Old Aug 29, 2009, 2:59 PM   #17
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I wish I knew what the AVCHD-Lite format was all about. It seems fuzzy, at best.

As for my meticulous attention to research, I just find it easier to totally understand what a camera is doing before I record a valuable video clip with it I have been working in Digital Video since the beginning, (a decade or so) and have accumulated a lot of tools Unfortunately, this time they let me down Anyway, I will keep on getting a better feel for what the ZS3 can actually do. It looks impressive.
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Old Aug 29, 2009, 7:18 PM   #18
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Even so the Panasonic ZS3 is an impressive camera from what I have seen plus they have one of the best OIS systems in the business.

So I take it the AVCHD from the Panasonic is actually a 60p container rather than 60i like the Canons?
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Old Aug 29, 2009, 11:30 PM   #19
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So I take it the AVCHD from the Panasonic is actually a 60p container rather than 60i like the Canons?
Yes, here are the parameters from MediaInfo:

General
ID : 0
Complete name : E:\temp\CineForm\00001.MTS
Format : BDAV
Format/Info : BluRay Video
File size : 12.9 MiB
Duration : 8s 480ms
Overall bit rate : 12.8 Mbps
Maximum Overall bit rate : 18.0 Mbps

Video
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : [email protected]
Format settings, CABAC : No
Format settings, ReFrames : 1 frame
Duration : 8s 475ms
Bit rate : 12.0 Mbps
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16/9
Frame rate : 59.940 fps
Standard : NTSC
Resolution : 24 bits
Colorimetry : 4:2:0
Scan type : Progressive
Bits/(Pixel*Frame) : 0.218
Stream size : 12.2 MiB (94%)

Audio
ID : 4352 (0x1100)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Duration : 8s 480ms
Bit rate mode : Constant
Bit rate : 192 Kbps
Channel(s) : 2 channels
Channel positions : L R
Sampling rate : 48.0 KHz
Stream size : 199 KiB (2%)
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Old Sep 2, 2009, 10:25 PM   #20
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Thanks. I just want to clear some things up Trevmar. (is there another Lumix camera that does 720p60, thought I might have seen an more expensive one in a more DSLR shaped body (but not actual)?

So, the camera is recording truly separate changing progressive frames 60 times a second not 30fps? Cineform is not automatically inserting frames to increase it from 30fps to 60fps?

Here is the hardest one, as some cameras do this trick. They get a 30p fame and they interpolate a 60p intermediate frame in camera. Is this camera doing it, or is it recording true 60 frames a second at the sensor (noting that Panasonic is claiming 30p at sensor)?

About teh 720p container discussion, an interesting thing about 720p, is that hdmi only has a 720p60 mode, 30p is doubled in this, maybe avchd is designed similar.
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