Date: Sat, 25 Jan 2003 21:13:08 +0900 From: Hidetoshi Shimokawa <simokawa@sat.t.u-tokyo.ac.jp> To: "Petr Holub" <hopet@ics.muni.cz> Cc: <freebsd-firewire@FreeBSD.ORG>, <ikob@FreeBSD.ORG>, <akimichi@sfc.wide.ad.jp> Subject: Re: reading from /dev/fw0? Message-ID: <ybsu1fxwhpn.wl@ett.sat.t.u-tokyo.ac.jp> In-Reply-To: <018f01c2c3db$9a4b3770$2603fb93@kloboucek> References: <ybsvg0ewyh5.wl@ett.sat.t.u-tokyo.ac.jp> <018f01c2c3db$9a4b3770$2603fb93@kloboucek>
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At Fri, 24 Jan 2003 20:05:47 +0100, Petr Holub wrote: > > > > I believe DV stream is OK because I wrote sending part > > > and DVcam can play a recorded stream without problem. > > > > > > http://people.freebsd.org/~simokawa/firewire/dv-20030115.tar.gz > > > > > > This should be complied and run on latest -current. > > I'm playing with dvrecv a bit more and I've found following problem: > from time to time the recorded DV file gets some blocks padded > and when replaying such a file I usually get twisted sound/video > from the point of padding on until the end of the file. > > I'm just curious whether it's problem of playdv or it's some error > in padding - due to nature of DV compression I would expect audio/video > gets back to normal playback after crossing some dropped information. > > Petr Because of inefficient queue management in the kernel, the queue over-run sometimes occurs on some systems. fwcontrol in -current and 4-stable allocates many buffers to prevent queue over/under run. Use -current or 4-stable, if you want use DV rather than SBP. I'd like to improve IT/IR queue management in the kernel. Block padding is adhoc work around for queue overrrun to keep fixed frame data size but it's just padding zeros. I don't know the right way to fill droped blocks. /\ Hidetoshi Shimokawa \/ simokawa@sat.t.u-tokyo.ac.jp PGP public key: http://www.sat.t.u-tokyo.ac.jp/~simokawa/pgp.html To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-firewire" in the body of the message
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