Problem playing edited AVCHD files

[AJ500]

I'd like to know if anyone is having a problem playing edited AVCHD DVD disks on their Blu-ray or PS3 player. I don't have either player, but use a Popcorn Hour media player to play my AVCHD files from a disk drive. It plays the unedited files flawlessly. But the files edited with VS11+ sometimes causes it to freeze at clip boundaries.

The AVCHD files come from a Sony HDR-CX7. VS11+ really looked promising because most of my editing is simple cuts, trims, and transitions. Not having to re-render 90% of the timeline is a MAJOR advantage of VS11+. But, they have to play on the PCH. The edited files play ok on a software player, so there must be something in the bitstream that's not compatible at the clip boundaries. Just wondering if the same problem is seen on Blu-ray players.

Also would like to have an option to output the files in a m2ts container instead of a mpeg container.

[Ken Berry]

I have a PS3 connected via HDMI to my 46" true high def HDTV (1920 x 1080p). And I have not had any trouble with my AVCHD hybrid discs. They play smoothly, with very good quality, and no blips at all. I also like the fact that VS11.5+ allows you to make menus for them. Apparently not all software packages that allow burning of hybrid discs have this option as yet. And it adds a touch of quality.

As a footnote, I would need to add that initially, I was dissatisfied with the first AVCHD discs I produced. But that was not because of any blips, but because the default bitrate in the Editor module for AVCHD files was too low in my opinion. You see, my camera is not AVCHD but HDV and so has a frame size of 1440 x 1080. I was thus choosing that frame size for conversion of my HDV to AVCHD for burning to disc. But the default bitrate, which cannot be changed in the existing template, was VBR 15000. And when burned to DVD, while clearly better than SD video, it was also very apparently of lower quality than the original HDV.

Choosing the alternative of converting the frame size to AVCHD 1920 x 1080 would have allowed a bitrate of 18000 kbps as used in many AVCHD cameras. But this in turn meant that I could only burn around 15 minutes of video to a disc, and a lot of my projects are around the 20 minute mark.

Now, I edit my HDV and insert the project file directly into the burning module. This allows me to choose my own bitrate and frame size. I now use 1920 x 1080 but a CBR of 16800/17000 kbps. That accommodates my 20 minute clips.

As a further footnote, the BDMV/STREAM folder on the resulting disc contains AVCHD files using the .m2ts extension.

And with the PS3 I have the luxury of being able to keep my original HDV format in edited form, copy it to a USB stick or external hard drive, and simply plug that into the PS3 and it recognises the HDV and plays it back fine. Again, no blips. It will also play a data DVD containing high def video of any format. And now that I have included the PS3 in my home network, I can stream video of any kind, including native and edited AVCHD and HDV, from my computer to the HDTV via the PS3. It is a remarkably flexible little device!! (And quite apart from all this, it also upscales standard DVDs to give them improved viewing quality on a large screen TV.)

[AJ500]

So, if I understand correctly, your AVCHD hyrid or Blu-ray stucture DVDs are being encoded from your HDV originals. In my case, VS11+ is using its smart-render capability to merge AVCHD clips together to produce an edited AVCHD file very quickly and with no quality reduction because it doesn't re-encode. That's the advantage I see with VS11+ over any other NLE at this point for working with AVCHD sources. But, it's not working perfectly with the Popcorn Hour. So close to getting what I want!

[Ken Berry]

Have you at least experimented with turning SmartRender off? Yes, AVCHD like all forms of mpeg is lossy. But I would have thought that maintaining the same high quality properties as the original, any loss of quality caused by a single recode would not be detectable by the human eye. Thus your main problem would be the extra time taken in the render.

However, I do understand your point that it should work *with* SmartRender and not produce those glitches...

[AJ500]

Yes, SmartRender Off produces an AVCHD file that plays flawlessly on the Popcorn Hour. The same project with SmartRender On freezes at the clip boundary.

I'm testing with two short clips taken with the CX7 on the timeline. No transitions or effects have been applied

SmartRender On:
Rendertime = 30 seconds which is about 1/2 realtime
Freezes on PCH at clip boundary

SmartRender Off:
Rendertime = 8m 10s which is about 8X realtime
Plays flawlessly on PCH

Here is the MediaInfo on the two clips:

SmartRender On

Code: Select all

General
ID                               : 0
Complete name                    : \\PCH2-OFFICE\share\Video\Test\Test02_SmartRender_On.mpg
Format                           : BDAV
Format/Info                      : BluRay Video
File size                        : 97.2 MiB
Duration                         : 1mn 6s
Overal bit rate                  : 12.3 Mbps
Maximum overal bit rate          : 20.6 Mbps

Video
ID                               : 4113 (0x1011)
Menu ID                          : 1 (0x1)
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format profile                   : Main@L4.0
Format settings, CABAC           : Yes
Format settings, ReFrames        : 2 frames
Duration                         : 1mn 6s
Bit rate                         : 11.4 Mbps
Width                            : 1440 pixels
Height                           : 1080 pixels
Display aspect ratio             : 16/9
Frame rate                       : 29.970 fps
Colorimetry                      : 4:2:0
Scan type                        : Interlaced
Scan order                       : Top Field First

Audio
ID                               : 4352 (0x1100)
Menu ID                          : 1 (0x1)
Format                           : AC-3
Format/Info                      : Audio Coding 3
Duration                         : 1mn 6s
Bit rate mode                    : Constant
Bit rate                         : 448 Kbps
Channel(s)                       : 6 channels
Channel positions                : Front: L C R, Rear: L R, LFE
Sampling rate                    : 48.0 KHz

SmartRender Off:

Code: Select all

General
ID                               : 0
Complete name                    : \\PCH2-OFFICE\share\Video\Test\Test02_SmartRender_Off.mpg
Format                           : BDAV
Format/Info                      : BluRay Video
File size                        : 84.4 MiB
Duration                         : 1mn 6s
Overal bit rate                  : 10.7 Mbps
Maximum overal bit rate          : 20.6 Mbps

Video
ID                               : 4113 (0x1011)
Menu ID                          : 1 (0x1)
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format profile                   : High@L4.0
Format settings, CABAC           : Yes
Format settings, ReFrames        : 2 frames
Duration                         : 1mn 6s
Bit rate                         : 9809 Kbps
Width                            : 1440 pixels
Height                           : 1080 pixels
Display aspect ratio             : 16/9
Frame rate                       : 29.970 fps
Standard                         : NTSC
Colorimetry                      : 4:2:0
Scan type                        : Interlaced
Scan order                       : Top Field First

Audio
ID                               : 4352 (0x1100)
Menu ID                          : 1 (0x1)
Format                           : AC-3
Format/Info                      : Audio Coding 3
Duration                         : 1mn 6s
Bit rate mode                    : Constant
Bit rate                         : 448 Kbps
Channel(s)                       : 6 channels
Channel positions                : Front: L C R, Rear: L R, LFE
Sampling rate                    : 48.0 KHz

The PCH can process Main@L4.0, so that's not the problem.

AJ

[bm707]

Yes, SmartRender Off produces an AVCHD file that plays flawlessly on the Popcorn Hour. The same project with SmartRender On freezes at the clip boundary.

Is it possible that there are any differences in the original clips, such as resolution, bitrate, field order, etc.? Any differences could cause the problem you observed. Sometimes the differences are not obvious, and could even originate with a corrupted file. As a simple test, can you smart-render the same clip twice end-to-end?

In any case, I always merge all of my clips before adding them into VS. I use the otherwise primitive software that shipped with my AVCHD camcorder, Pixela ImageMixer 3, for that task. Per my understanding, you can also merge AVCHD clips by copying them and manually combining the files. As long as the properties are identical, it should work, although I've never personally tried it.

If this doesn't help, then you might be stuck re-rendering every time. Good luck.

[Ken Berry]

Just a comment, as I have no suggestions to make: I was fascinated to see that the non-SmartRendered video had a significantly lower overall bitrate (10.7 Mbps) than the SmartRendered one (12.3 Mbps). Notionally, that suggests that the non-SmartRendered one should indeed be lower quality. On the other hand, it you used 100% on the quality slider, and two pass encode (which I have not got to work on AVCHD), it could also suggest that the full render, taking much longer, meant that VS analysed the video more accurately and could thus use a lower bitrate for the same level of quality...?

It is also an interesting commentary on the real average bitrate used when you choose VBR max 18 Mbps which is what I presume you did -- though how that squares with your 'maximum overal bit rate' of 20.6 Mbps, I don't know...