Major problem with AVCHD editing, mpeg optimizer

[pac007]

Version number: 11.5.0157.2 Plus
PC: XP SP2, Core 2 Duo
Camcorder: Canon HG10

I do only basic AVCHD editing: cut, trim and join clips from my Canon HG10 Pal AVCHD camcorder. I use the smart encoding (MPEG optimizer) feature of VS .

Problem description:
Edited clips will stop playing or stutter around editing points. The playback problems with edited clips appear on my Dvico Twix 4100SH hard disk media player and on my PC with CoreAVC codec (I did not try PS3 yet).

If I force VS to reencode the same project in AVCHD, the reencoded clip works fine!!!

If I only join the clips imported from the camcorder NO cut or trim, the edited clips playback fine on my PC, and Dvico.

[Ken Berry]

Welcome to the forums ... and, to flog an almost dead horse, the wonderful world of trying to edit and play AVCHD!!!

What happens if you don't use the MPEG optimizer?

And try playing it in your PS2, just to see if the problem is consistent across a range of players...

[pac007]

Ken,

answers to your questions:

What happens if you don't use the MPEG optimizer?:
It works fine!. If I force vs to reencode the same clip,the reencoded clip plays back without any problem. Unfortunatelly it takes a lot of time, it is the smart encode (mpeg optimizer) feature I got vs in the first place.

And try playing it in your PS2, just to see if the problem is consistent across a range of players...: I do not have a PS3. My friend have a Popcorn Hour A100 hd media player with AVCHD capability, which plays back the same clip as my DVICO Tvix stuttering and at the 4th editing point it stops playing.

You can download the problematic clip from here:
http://www.babanotesz.hu/vs_11p_avchd_t ... recode.mpg

More people have the same problem with other kind of players:
http://www.avsforum.com/avs-vb/showthread.php?t=1033982

[Ken Berry]

Sorry. What you said "(I did not try PS3 yet)", I thought this indicated you had one but had not used it yet for this purpose.

I think there may also be a slight confusion between the m peg optimizer feature and SmartRender, which is what I think you are calling smart encode. The mpeg optimizer looks at your video recommends better settings for it. SmartRender only works when you are using the same format video throughout and with exactly the same properties throughout as well. As you probably know, it does not re-render most of the video, only those parts around edits. But if you change the properties (as mpeg optimizer might recommend) SmartRender doesn't work anyway. The other thing you need to bear in mind is that with the high resolutions settings of high definition video such as AVCHD, you can probably re-encode a couple of times without being able to notice the slightest bit of quality loss.

So I have to ask whether you change the properties of your video at any time? For instance, it is probably captured at a (constant?) bitrate of 16,800 kbps. But if you render it using the VS defaults, that changes the bitrate to variable with a maximum of 15,000 kbps. So what exactly do you do, and how do you do it? Can you also right click on one of your files in VS, either in the timeline or in the library window, and copy all its properties here please.

I will take a look at your file, but won't be able to get around to it immediately. I am in the middle of doing my own high def editing project on a recent visit I made to Madrid...

[Ken Berry]

I have tried several times to download your file, but it just hangs. The last time I left it for about 3 hours but there was no movement. For a 120 MB file, I thought that would have been enough, but it seems nothing even began to download. I even weht to the source directory and then selected the download file separately. But all I got (curiously) was a QuickTime symbol on screen, and no download. I don't have QT associated with AVCHD so am not sure why it should be so...

[Ken Berry]

Next day, and still trying to download your file. But neither my download manager, which normally kicks in automatically, nor the usual Windows download messages, appear. I get the QT symbol and that is all. Will let it run for a couple of hours and see if anything eventuates.

[pac007]

Ken,

I always use rendering properties "Same as first video clip", I use clips straight from the camera no differences among them. I also positive that this way there is no reencoding because the rendering time is very short (same as copying the individual files).

The clip properties within the project (all the same except the frame number):
H.264 Video, Upper Field First
XXX frames
24 bits, 1440 x 1080, 16:9
25.000 frames/sec
Variable bit rate (Max. 16000 kbps)

I will upload the sample clip with different extension (mts) so Quicktime will not try to play it.

[Ken Berry]

Thanks for the extra info -- and also the new download arrangement. I left the link established to the other site for 8 hours, and it finally said 'Done'. But there had never been any indication of any download. And I have done a deep, advanced search of my entire computer (6 drives) and have found no trace of a downloaded file of that name... I even searched the temp files. Nada.

My only concern about using Same As First Clip relates to possible editing. I for instance always add something different at the start of a project, so selecting Same As First Clip takes on those properties, and not necessarily the properties of the great majority of clips... But if you didn't add anything at the beginning, then this concern should not arise in your case.

[pac007]

The sample clip with mts extension:

http://www.babanotesz.hu/vs_11p_avchd_t ... recode.mts

[Ken Berry]

That's better! Currently downloading. Will get back to you when I have chance to play around with it.

[Ken Berry]

The file played perfectly smoothly on my PS3. I simply copied it as you sent it, onto a USB stick drive and plugged that into the PS3. The PS3 had no trouble recognising and playing it. There were no artifacts of any kind. The only slightly choppy motion was at the very end of the first clip, but that is one or two frames of camera shake on that part of the video, and had nothing to do with the cut itself. No other choppiness observed. As I say, it was smooth throughout and good quality. (It also looked like fun! What is the language -- Polish?)

I also played it, by changing the .mts extension to .mpg, on PowerDVD 8 deluxe edition and Nero Show Time version 4.3.2.0 (in Nero 8 ). Both also played it perfectly, smoothly and with no choppiness, fullscreen on my 22 inch LCD monitor. It also played, again totally smoothly, on Windows Media Player, though in this case there was no audio (I am not sure why). All other players played the audio with no problems.

VS11.5+ in Clip mode also played it smoothly and with audio. In Project mode, motion was jerky. But I am not surprised by that as I get the same thing with my own HDV clips played back in Project mode.

So what can I say? No problems at all this end (apart from the sound question in WMP)... Let me know if you want me to carry out any other experiments with the video.

[pac007]

Conclusion: PS3, Cyberlink plays it smoothly Dvico, Popcorn Hour, CoreAVC does not.

So I have to change hardware or recode everything... no easy solution :(.

Anyway thanks for your support Ken!