Panning Judder on PC playback

[Ikarus73]

Hi,

Although I'm a PC enthusiast, I'm a newbie to the world of digital camcorders, and have just bought a Panasonic HDC-SD5, with which I'm happy, but would appreciate advice on understanding one particular issue which is only apparent when playing back recordings on a PC; Judder when Panning.

My recordings (1080i) are perfectly smooth when played back on my Panasonic TH42PX600 plasma using the camcorder, and HDMI connection. However, If I play back the AVCHD .MTS files on either my Laptop (ASUS G1S), or my Desktop (Core2DUO @3G, 8800GTS) ,when panning, the motion is very juddery. Also, if I play the .MTS files on my G1S , and connect it to my Panasonic TV via HDMI, I still see the judder, so this leads me to believe it's not just monitor/refresh rate related.

I've tried various codecs, using K-LITE, FFV, NERO Showtime, tried the supplied Panasonic HD Writer. It's the same with them all.

After reading several threads, I was almost lead to believe that even my desktop couldn't decode the AVCHD files quick enough. But on my G1S, both cores are at less than 70 percent during direct playback, and also, if I use the panasonic software to convert to mp2, or NERO to convert to mp2, or DivX, the resultant conversions also inherit the judder. This cannot be down to the PC's inability to decode the .MTS in realtime, because the conversion doesn't take place in real time, but takes as long as is neccesary.

What I have noticed however, is that if I use NERO 8 to make a DVD, and play the DVD in my Panasonic DVD recorder (Standard definition of course), then the DVD plays almost as smoothly as the original does using the camcorder. If I try and play the same DVD directly using either PC, the judder is still present.

I understand the different HD formats, a and the principle behind the interlace format (in this case, 1080i), and I don't think the interlacing of the original is the problem.

My latest theory is that the judder can be seen on the PC because the PC monitors' refresh rates are 60Hz, and the recording was at 50Hz (2 x25 interlaced - or that's how I understand it), and so the judder can be seen. But that doesn't explain why I can watch other video clips, or DVD movies on my PC's without experiencing judder.

My conclusion is that the only way to see judder-free footage is either to burn a standard-definition DVD, and play it back on the Panasonic DVD player, or to play back in HD, using the Camcorder.

What does the DVD player and the Camcorder do differently that means there is no judder ??

My aim of investing in a Digital Camcorder was so that I can digitally Archive family recordings, and either copy them to disk in High Definition (In the future, when I invest in a player), or even to Standard definition like I did during my tests. After my initial findings It appeared that simply archiving individual .MTS files would not give me the quality archives I required, but since making the standard definition DVD, and seeing that there was no judder, I now think that archiving the .MTS files is fine.
At this stage, I am assuming that if, in the future, I was to burn to High Definition media, with the appropriate burner, of course, that I would be able to produce judder free movies. At this stage, without this equipment, it is only an assumption, and I would appreciate advice from those in the know.

What I also noticed was that when I accidentally burned a DVD in AVCHD format using the Panasonic HD Writer software, when I inserted the disc into my G1S, the box that popped up identified the disc as a "Blu-ray Disc". Excuse my ignorance, as I don't know anything about the specifics of blu-ray, but does that mean that the folder/files format that my camera writes to the SDHC cards, and the same one that the software burned to the disc, i.e. with folders AVCHDT, BDMV etc is exactly the same as those on a blue ray disc ? If so then, is "blu-ray" simply this file/folder structure residing on blu-ray specific high-storage capacity discs ?

Thanks in anticipation,

Ik.

[senu]

Originally Posted by Ikarus73

; Judder when Panning.

My recordings (1080i) are perfectly smooth when played back on my Panasonic TH42PX600 plasma using the camcorder, and HDMI connection. However, If I play back the AVCHD .MTS files on either my Laptop (ASUS G1S), or my Desktop (Core2DUO @3G, 8800GTS) ,when panning, the motion is very juddery. Also, if I play the .MTS files on my G1S , and connect it to my Panasonic TV via HDMI, I still see the judder, so this leads me to believe it's not just monitor/refresh rate related.

What is the frame rate of playback? That may be the culprit, and directly related to the hardware (computer processor) struggling

I've tried various codecs, using K-LITE, FFV, NERO Showtime, tried the supplied Panasonic HD Writer. It's the same with them all.

Even Core AVC pro?

After reading several threads, I was almost lead to believe that even my desktop couldn't decode the AVCHD files quick enough. But on my G1S, both cores are at less than 70 percent during direct playback, and also, if I use the panasonic software to convert to mp2, or NERO to convert to mp2, or DivX, the resultant conversions also inherit the judder. This cannot be down to the PC's inability to decode the .MTS in realtime, because the conversion doesn't take place in real time, but takes as long as is neccesary.

It may, I have converted mts files to m2t , get far less or no judder but native m2t files play fine .. This is with a P4 3.0Ghz with 2.0Gb RAM

What I have noticed however, is that if I use NERO 8 to make a DVD, and play the DVD in my Panasonic DVD recorder (Standard definition of course), then the DVD plays almost as smoothly as the original does using the camcorder. If I try and play the same DVD directly using either PC, the judder is still present.

This is not right , SD footage should not. However I would have said the "judder" was inherent to footage as panning is one thing AVCHD camcorders do very badly. The more recent ones ( HG10 ect) are much better

My latest theory is that the judder can be seen on the PC because the PC monitors' refresh rates are 60Hz, and the recording was at 50Hz (2 x25 interlaced - or that's how I understand it), and so the judder can be seen. But that doesn't explain why I can watch other video clips, or DVD movies on my PC's without experiencing judder.

PC monitors refresh rate can be changed to see if this is the case. i dont think it is

My conclusion is that the only way to see judder-free footage is either to burn a standard-definition DVD, and play it back on the Panasonic DVD player, or to play back in HD, using the Camcorder.

Don't give up trying on the PC..

What does the DVD player and the Camcorder do differently that means there is no judder ??

With the camcorder there is no use of PC processor power but the DVD playback is harder to explain.

What I also noticed was that when I accidentally burned a DVD in AVCHD format using the Panasonic HD Writer software, when I inserted the disc into my G1S, the box that popped up identified the disc as a "Blu-ray Disc". Excuse my ignorance, as I don't know anything about the specifics of blu-ray, but does that mean that the folder/files format that my camera writes to the SDHC cards, and the same one that the software burned to the disc, i.e. with folders AVCHDT, BDMV etc is exactly the same as those on a blue ray disc ? If so then, is "blu-ray" simply this file/folder structure residing on blu-ray specific high-storage capacity discs ?

Yes

[Ikarus73]

Thanks for your reply Senu.

I would say the judder is not inherrent to the footage because there is no judder at all when played back through the camcorder.

I'll take a look at CoreAV.

My G1S refresh rate is 60HZ. It's the only one displayed in the Nvidia control panel, and I think the majority of LCD monitors are fixed at this res. Although I'll take a look at my desktop later.

[senu]

It would be interesting to see what playback to a TV via a PS3 would be like..

[leaft]

Have you tried another player, Media player classic (included in the CCCP codec paxk I think) does seam to handle video sheering problems better than other players.

[rhubarbe]

I had this problem with my Japanese HDC-SD7 (an NTSC cam). I know that the footage is OK because through the cam or on the TV it doesn't judder, but on the PC it does.

In Nero Showtime 4 (Nero 8) there is a facility to show the framerate and it's only with Nero Showtime 4 (not 3) that my video plays at the correct framerate on my C2D 2.4GHz E6600 PC, even though the CPU is not maxed out using Nero Showtime 3 I only get 27.2fps instead of the 30fps I need.

I downloaded some SD5 footage from a PAL SD5 and Nero Showtimne 3 played it back at 22.5fps. Nero Showtime 4 plays it at 25fps.

It's not your monitor because my cam outputs 60i and my monitor refreshes at 60Hz.

I tried MPC and CoreAVC and that combo is worse than Nero Showtime 3.

[leaft]

The only other problem I have come accross like this I think I fixed by using the reduce Interlace flicker in Vegas 7.0

[Ikarus73]

O.K. I checked with Nero Showtime 4 (Came with Nero 8).

1080i (1920 x 1080) - Framerate on Asus G1S is 25FPS. Never even flutters. I believe this is correct (Interlaced 50i = 2 X 25) Bitrate between 11.68 and 12.8 Mbit/s.

Tried Media Player, Media player Classic, Nero Showtime 4, Windows Media Centre, all the same result on both PC's. There's a section on my test footage where I pan quickly along the fence in my garden. It's smooth as silk when I play back the footage directly from the camcorder (HDMI), and so is the converted, downgraded SD DVD, when played through the Panasonic DVD-Recorder, but like I say, the same DVD is jerky when panning on both PC's. When Panning, the footage is even jerky if I play the .MTS directly from the Laptop via the HDMI connection, straight into the HDMI of the Panasonic TV. The same Jerkiness as when I play and view on the PC monitor.

I've also just updated 8600M GT driver to 174.61. Still the same, but expected it to be, as my desktop is running a different driver from the previous one.

[glesgaguyav]

Is this not the general problem with MTS files? any MTS files that I have downloaded play in a stop/start manner.
If however they are converted to M2T they play perfectly
If you need to watch on a PC then why not just convert ?

[Ikarus73]

I've just been watching it again, and I would say it's actually Blurry when panning, rather than jerky. The best way to describe it would be if there was small writing written along the fence, it could be read clearly when the camera is stationary, but when panning, it would be blurry to the extent that you wouldn't be able to read it.

It's almost as though direct playback from the camera, and from the DVD recorder quadruples the frame rate when compared with the PC. Again, it's only noticeable when panning, although I havent tried taking footage of fast moving objects yet.

There's absoultely no start/stop at all, the framerate is consistant, but just appears much lower on the PC, despite the reported 25fps from Nero Showtime, and it only shows on panning, but it strains your eyes to (try and) watch it.

I'm still not sure about the whole framerate thing on HD anyway. I know what 25fps looks like on a FPS game (Crysis, COD4 etc) - blurry, choppy, whatever you want to call it, exactly like my footage when played back on either PC, but not like my footage played back through the camcorder, or on the DVD player, where the playback is silky smooth, and looks like playing a FPS game at over 60 FPS.

The more I think about it, I can't really understand how a screen that has a refresh rate of 60Hz is ever going to display motion clips at 25 fps smoothly anyway, but if the effective framerate of 1080i is 25fps anyway, why does the 25fps look so smooth through the camcorder, or through the SCART connector from the Panasonic DVD recorder in RGB (Which is an analogue signal anyway).

Maybe if I had a way of forcing my LCD monitor to display at 25Hz, I'd think everything was O.K. ??

[glesgaguyav]

Originally Posted by Ikarus73

The best way to describe it would be if there was small writing written along the fence, it could be read clearly when the camera is stationary, but when panning, it would be blurry to the extent that you wouldn't be able to read it.

Is that not normal for Video? a panning shot will never capture crisp clear video, indeed most videographers will tell you that the first rule is "never use a Panning shot" and if you do make it very slow and with a steady camera, the only way to improve this is with higher Bit Rates M2T files have higher bitrates than MTS

[senu]

Originally Posted by glesgaguyav

Is that not normal for Video? a panning shot will never capture crisp clear video, indeed most videographers will tell you that the first rule is "never use a Panning shot" and if you do make it very slow and with a steady camera, the only way to improve this is with higher Bit Rates M2T files have higher bitrates than MTS

This is true as most "pro" footage doesnot contain any panning
What is equally true is that for consumer camcorders
Panning shots look poor in this order SD tape; SD HDD: HDV: AVCHD
However I Panned a 5 min footage on HDV and output as
m2t
SD mpeg2
WMV-HD
Quicktime
And simultaneously shot with the HG 10 also panning

There was Judder with the mts files : this reduced but did not vanish with the SD files made from them
With the HDV it was hard to see any judder with the WMV-HD and quicktime and the m2t as well
Also Power DVD 7 ultra and Nero Showtime were the best playback players

Judder from mts was all but removed converted to m2t
Perhaps pseudo- scientific but I was just trying to see how well AVCHD panning had improved and compare it to HDV

Also played via the PS3 there was a little judder on a 46 " Samsung 100Hz 24p 1080p LCD which was not present on a Sony Bravia 40" 1080p

In either case, there was no judder via directly played footage from camcorder to TV

[rhubarbe]

I tell you that this is just the same problem that I have been writing about for the last six months: tearing, clicking, juddering, it's all a manifestation of the same phenomenon.

I think it's something to do with the way the Panasonic AVCHD is encoded. Isn't there a difference between Sony and Panasonic? And which camp does Canon's AVCHD fall into?

[glesgaguyav]

Originally Posted by rhubarbe

I think it's something to do with the way the Panasonic AVCHD is encoded. Isn't there a difference between Sony and Panasonic? And which camp does Canon's AVCHD fall into?

Sensible question

As Harry Hill might say....."FIIIIGHT"

[senu]

I have a feeling there will be a deafening silence on that one..
Of course, they are not different.. Yeah right!