AVCHD from JVC

GenJerDan wrote on 8/10/2013, 5:46 PM

Just got a cheapo JVC Everio HD camera and everything seems to be working fine. (Yay, pawnshops!)

But on the timeline of Vegas Pro 12, every once in a while the footage will stop and start, then later on I'll get random frames showing up in the preview right in the middle of something else. They do NOT show up on the timeline itself, and they do not render. The stops and starts don't render, either.

But it all makes editing...interesting.

What causes this? The GOP structure? Space aliens?

Any fix to this annoyance? Do I have something set wrong?

The original footage is (according to Vegas):

Video: 29.970 fps interlaced, 1920x1080x12, AVC
Audio: 48,000 Hz, Stereo, Dolby AC-3

and comes as a .mts file.

Comments

PeterDuke wrote on 8/10/2013, 6:42 PM

What does Mediainfo say about the video? Please post the tree-view info.

http://mediaarea.net/en/MediaInfo/Download

GenJerDan wrote on 8/10/2013, 7:14 PM

General
ID : 0 (0x0)
Complete name : E:\00060.MTS
Format : BDAV
Format/Info : Blu-ray Video
File size : 186 MiB
Duration : 1mn 5s
Overall bit rate mode : Variable
Overall bit rate : 23.9 Mbps
Maximum Overall bit rate : 24.0 Mbps

Video
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.0
Format settings, CABAC : No
Format settings, ReFrames : 2 frames
Format settings, GOP : M=2, N=14
Codec ID : 27
Duration : 1mn 5s
Bit rate mode : Variable
Bit rate : 22.6 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 29.970 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Interlaced
Scan order : Top Field First
Bits/(Pixel*Frame) : 0.364
Stream size : 177 MiB (95%)

Audio
ID : 4352 (0x1100)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Mode extension : CM (complete main)
Format settings, Endianness : Big
Codec ID : 129
Duration : 1mn 5s
Bit rate mode : Constant
Bit rate : 256 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 KHz
Bit depth : 16 bits
Compression mode : Lossy
Delay relative to video : -34ms
Stream size : 2.00 MiB (1%)

Text
ID : 4608 (0x1200)
Menu ID : 1 (0x1)
Format : PGS
Codec ID : 144
Duration : 1mn 4s
Delay relative to video : -34ms

PeterDuke wrote on 8/10/2013, 7:29 PM

Nothing stands out there for me. Maybe someone else will spot something. Your system specs look adequate. What preview quality do you have Vegas set to? At the highest quality it is quite possible that you will get some stuttering.

GenJerDan wrote on 8/10/2013, 7:51 PM

Well, the random frames that pop up on the preview (Good : Auto) aren't from anywhere near the current frame, so it doesn't seem like a real stutter.

It's like it's grabbing a random frame from somewhere else as "filler".

Of course, spreading out the timeline to see each frame...there is no gap to fill, but the frame that has one image on the timeline shows a different one (wrong one) in the preview.

set wrote on 8/10/2013, 7:58 PM

Compares to mine, only one thing I found different, but will this affect a lot?

JVC:
Format settings, GOP : M=2, N=14

Sony AVCHD recording at 17Mbps :
Format settings, GOP : M=2, N=13

Sony AVCHD recording at 24Mbps :
Format settings, ReFrames: 2 frames

GenJerDan wrote on 8/10/2013, 8:16 PM

Maybe the GOP.

I don't think the recording "speed" would do it...

...and I could drop mine down to 17 and see what happens.

But not tonight. :p

EDIT: Couldn't resist. Tried it at 17 and it still does it. (There are no other settings I can change.)

GenJerDan wrote on 8/11/2013, 4:29 PM

Huh.

Dropping the Preview quality down to Preview (Auto) makes the problem go away.

Does that make it a bug?