Re: [libdv-dev] Continuous "audio block/sample failure" with JVC DV camera

[Marko <mar...@hu...>]

Hi Nathan,

> Whenever I dump DV from my JVC camera I get continuous lines like:
> 
>    asf 00:00:00.00 2000-00-00 00:00:00 70 b7 08 12 2/48
>    ...above repeated 30 times...
>    # audio block/sample failure for 0 blocks, 60 samples of 1280
> 
> The resulting audio stream sounds odd, with little breaks in it. (As one 
> might expect if 60 out of every 1280 audio samples were bad.)
> 
> Details:
> --------
> Camera:     JVC GR-DVL28 (PAL)
> OS:         Mandrake 10, 2.6 kernel
> Libdv:      libdv 0.102  (libdv4-0.102-1mdk.rpm package)
> Other libs: libraw1394_5-0.9.0-4mdk, libdc1394_0-0.9.2-1mdk,
>             libavc1394_0-0.4.1-4mdk
[..]
> https://core.fluendo.com/trac/cgi-bin/trac.cgi/ticket/67
> which suggests there is a problem with JVC cameras and libdv.
> 
> So my questions: Has anyone else experienced this?  Is this a known 
> problem? Is there any workaround/fix?  Is there any more info I should 
> supply?

I have a JVC GR-DVL9600 (PAL), and audio has worked for me, except for some
occasional glitches, probably due to errors on the tape.  I've been using
libdv with the 2.4 kernel since 2.4.21 or so.

On a somewhat related note, there's a DV camera based backup utility whose name
escapes me right now.  My camera refused to record anything created by
that utility with the default settings.  If I remember correctly, there was
some option that generated silent audio instead of using the audio bandwidth
for the payload.  With that option, my camera recorded the data.  However,
playback didn't work reliably, even though I used the accompanying program
that adds redundance and spreads each byte across several blocks.

	Marko