AC130: no audio in joined files

J

Jglenn

Member
I am trying to get the video from the sd card of my ac-130 to my computer and the audio files will not copy. I have copied the entire private folder into my computer and then the files are recognized by vegas pro 11, however there is an audio drop out at the join. When I use the mts joiner program, the clips are joined into on, however there is no audio in the clip. Can anyone tell me how to extract and join the clips to vegas.
 
How long is the dropout??? I, before being advised by Barry, used to take the files from stream only and if a file was in excess of 4GB I used to get a short section of "blank audio" but also blank video. If I simply chopped the end of the blank section I had no issues at all and the video and audio was seamless....have you actually tried dragging the black portion backwards and lining it up on the Vegas time line and playing it??? Is the video and audio totally seamless?? It's very strange because on my HMC cameras it's 100% seamless if you join files on the timeline. Is there definately only a audio dropout before the file changes over or is the camera giving you a couple of extra frames of both blank audio and video??

Chris
 
The dropout is less than a second and the video doesn't black out. I had done some tests before I shot this show and used the mts joiner from panasonic that worked well. I'm doing everything the same now and dragging the private folder into my computer and then I can open the files up but with the audio drop between clips. If I use the mts join program, they appear as one clip but no audio at all. Do you know why the audio would not be present when the clips are joined?
 
When I use the mts joiner, the clips will join as one file, however there is a few seconds of audio at the start of the first clip and a few seconds at the end of the last clip and everything else is blank. Video portion is fine but no audio except the few seconds at the first and last is in the output file. Need help!!!!!
 
Okay, see, the problem is you're going about it the wrong way. You're going about it back-to-front, instead of doing it the right way. You shouldn't have to try to run some clip-joining software or whatever. That's just muddying the waters.

Vegas has a feature called the "device explorer" which will import long spanned clips seamlessly. That's how you should be importing the files.

Never, ever just copy the .MTS files off the cards and try to use those -- you're asking for trouble when you do that. Use the system as it was designed -- ALWAYS copy the entire PRIVATE directory. And don't try to import individual MTS files from the STREAM directory, that's the wrong way to do it. Instead, use your NLE's specific import tool -- for Premiere Pro it's the Media Browser, for Vegas it's the Device Explorer, etc. Those import modules are designed to know about and cope with spanned clips.
 
I tried using the nle to bring the files over and that's where they are dropping the frames. The files play fine on the camera so the information is there. I copied the entire private folder onto my computer and and then tried the device explorer but the same few frames are still dropped at the end of each clip. Using the AVCCAM viewer and bringing the clips into the editor with the card in the camera produces the same results. I am about at my wits end trying to figure this out. The reason I was using the mts joiner was to alleviate this problem and it did the job in my tests a couple of weeks ago, however now the audio is not present. I recorded the clips in 720 60p. Is the audio pcm in this format or aac03? Thank you for your help.
 
If you shot on an AC130, the audio has to be AC3. The AC130 doesn't have LPCM audio.

The information is definitely there as recorded by the camera, and as you've verified by playing back from the camera. Are you saying that importing via the Device Explorer is creating clips with dropped-out audio? If so, that's just plain a bug in Vegas and would need to be reported to them.

So to clarify, you copied the entire PRIVATE directory over, and are now using the Device Explorer to import the files (no dragging & dropping of MTS files, but using the Device Explorer)? That's supposed to be the way to avoid the problem, in Vegas.
 
I just downloaded shot put pro in the trial version and offloaded the same clips from the card and got the same result. Still drops about 12 or 13 frames of audio.
 
Thanks for your help Barry, I copied the whole directory over and used the device explorer and still have the same problem. I also downloaded shot put pro and got the same drop outs when offloading it. The AVCCAM viewer also shows the same drop outs at the end of each 4g clip. Is there possibly a way to stream it the actual video out of the camcorder? I tried connecting the camcorder to my computer via usb and getting to the files that way through device explorer and still have the same dropped frames. I do have another sound track but the video also has some dropped frames at this point and I just can't sync it all up without looking funny at the drop frame point.
 
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How frustrating... I assure you the files are complete. I would be willing to bet that if you imported them into Premiere Pro CS6, they'd come in flawlessly.

But if Vegas refuses to import it, you're going to have to resort to some workaround or other. Have you tried some of the other "joining" techniques like the command-line copy technique?
 
I tried the command line copy but I can get to the private folder, however when I then type cd \avchd I get a message that the path isn't recognized even though I can type dir and see the avchd folder in the private directory. With the alternate audio source I recorded, I was able to get enough on the time line to edit but I won't be using this camcorder in the hd mode until I can seamlessly extract the files, otherwise it is kind of useless. Is it possible that the camcorder isn't writing some meta data onto the card that would allow for seamless file extraction? I called panasonic support but they had no idea and couldn't tell me why their avccam viewer wouldn't even show the video seamless. Will I get just as good a final product if I use the sd 480 30p, or would you use the 480 60i in sd mode?
 
I must admit that my HMC cameras do a far better job if the files go over 4GB ...even just copying the files direct from the stream folder onto my computer drive and butting up the two files gives me flawless results so the firmware must be different??

Maybe you could do a pause around the 20 minute mark and record again at a convenient break in the proceeding?? I do that at weddings by choice and turn the main cam off while the couple are signing the register. What are you actually recording and is it possible to force a break??? That isn't the ideal situation but at least the cam will record correctly up to the clip end and all you need to do is trim it?? If it is definately missing some audio when the file reaches limits I would be inclined to send it in for a warrany repair ...even if you use the stream MTS files direct there shouldn't be any parts with no audio. You say the camera plays back the file perfectly?? Are you 100% sure there isn't a tiny gap between the two ?? Try selecting both files on the card and then play in either WMP or VLC player and skip thru the first clip until you are almost at the end and then listen VERY carefully to the changeover!! The number of frames you are talking about is close to 1/2 - 3/4 second so it's hard to actually see if the files actually play the break in audio...

I have done tests using SD on both of my cameras and then HD rendered down to SD MPEG2 and there is a BIG difference...with an NSTC camera with a smaller SD frame size (mine are 576i not 480i) it will be even lower! I would definately shoot in HD and render back to SD...it's easy in Vegas ! If you shoot interlaced then you need to set the de-interlacing to BLEND...progressive you can turn it off and the other neat trick is to add the Sony Sharpen plugin to all video tracks BUT leave the letting at zero (I have no idea why it makes the footage a lot better but it does!!!)

Just another interesting point??? In SD you will reach the 4GB limit a lot quicker as the files are bigger from the camera. Do you have the same issue in SD shoots with split files??? (Last bit of audio is missing)

Hope you sort it out

Chris
 
Thanks for all the assistance. The interesting thing is that in SD mode I can just go to that folder and drag them into Vegas and it is all seamless, no missing frames. I will try the VLC player and see if they are seamless there.
 
I will be doing a concert Friday at 720/24p - it will for sure run over 4GB so I can listen at the interface to see if I can detect any losses. I am on Vegas 10. If you have a different version then the test will be inconclusive. Difficult to do a test like this because you never know what is going on/not going on at the time of the split.
 
I'm using Vegas 11. It seems as though the splits always happen in the middle of a song. It would really be nice if it was possible to split clips when there was a pause in the program for a few seconds.
 
Jglenn said:
I tried the command line copy but I can get to the private folder, however when I then type cd \avchd I get a message that the path isn't recognized even though I can type dir and see the avchd folder in the private directory.
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Do you still have the footage on an SD card? Because it's things like this that make me think you must have a botched copy on the hard disk somehow.

I won't be using this camcorder in the hd mode until I can seamlessly extract the files, otherwise it is kind of useless.
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The camcorder produces seamless files. I don't know what happened in your workflow that caused you this difficulty, but it is absolutely atypical. The camcorders were designed from the ground up to provide for seamless file spanning, and when the NLEs are used properly to import the files, seamless spanning is what you get. Again, your experience here is absolutely not normal, and I haven't done that exact combination so I don't know where the problem is.

Is it possible that the camcorder isn't writing some meta data onto the card that would allow for seamless file extraction?
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Absolutely not. The camcorder is AVCHD-standard, and it writes out every file that is necessary to comply with the AVCHD standard, and the AVCHD standard calls for seamless file spanning. Again, I guarantee you that the camcorder by itself is performing properly (unless you have a defective unit, which could then be causing any number of unforeseen complications). So I guess I should say "a normally-functioning AVCHD camcorder is absolutely guaranteed to write out every jot of information necessary to properly allow for seamless file spanning."

Will I get just as good a final product if I use the sd 480 30p, or would you use the 480 60i in sd mode?
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Depends on if you want the "live" look, or the "filmic" look. 30p isn't actually filmic, but it's more like filmic than it is "live". In any case, if your target delivery is standard-def DVD, shooting in 480 is a perfectly reasonable choice. However, be aware that the standard-def mode takes up just as much space on the memory card as high-def (more, actually; HD PH mode takes 24mbits, and standard-def DV takes 25 megabits). So you'll have the exact same file spanning issue when clips exceed the same 4GB limit. The only real difference at that point is that you'd be dealing with DV .AVI files instead of MPEG-2 .mts files, so maybe Vegas would have an easier time stitching together DV .AVI files?
 
ChrisHarding said:
I must admit that my HMC cameras do a far better job if the files go over 4GB ...even just copying the files direct from the stream folder onto my computer drive and butting up the two files gives me flawless results so the firmware must be different??
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There is absolutely no difference. Both the AC130 and the HMC series use AVCHD with PH mode. They are the same.


You say the camera plays back the file perfectly??
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He did, and this is what tells me that his camcorder is functioning properly and that the data absolutely *is* there and that it is possible to make a seamless edit of it. And that therefore something is malfunctioning either in the copy of the data that he made, or there's a bug in the NLE.
 
Do you still have the footage on an SD card? Because it's things like this that make me think you must have a botched copy on the hard disk somehow.
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Perhaps there is an issue with the SD Card itself. What brand and speed rating is the card?

Is there a possibility that the card could have been used earlier on a different camcorder, and not reformatted on the AC130 for use with it? Besides my AC130 I also have a Canon HF G10, a Nikon D90, and a Panasonic GH2. I found that I have to be careful in not accidentally using a card formatted on another camera in my AC130. While everything seems to record OK, I've then had weird issues importing the files.
 
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I haven't yet downloaded the VLC player to check the files on that. I purchased 8 new san disk extreme class cards with the camcorder and formatted them all in the camera upon recieving them. Would it have mattered if I had been in the SD mode when I formatted the cards? I don't remember if I was or not. The video I shot was over an hour and a half for the first part and about 2 hours for the second. I was recording in 720 60p using simutaneous record and have the same problem with all cards. The thing is I don't know why when I tested in the SD mode all clips were seamless. I have also tried offloading them in my old computer with no luck there either. I do still have the footage on an SD card and I tried another new card at home just letting the camcorder run until it would make a split and that copy also has the missing audio at the end of the clip.
 
Just for interest was the new card you tried formatted in AVCHD mode??? I must admit I never tried that as I never use DV mode and when you did the new card did you just use one slot??

It seems very strange ...the only thing I did notice is on the 130 mine did leave a gap at the end with no video and no audio which I had to trim back...the HMC's I know don't leave any gap so it might be the fact that it's a dual slot camera but it's highly doubtful!! Just grasping at straws here but would the fact that you are running double frame rate have anything to do with it??? Maybe try the same card, formatted in AVCHD mode and shoot the test in normal PH mode 1080 50 or 60i ?

It will be interesting to see what caused the issue!!

Chris
 
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