From owner-freebsd-hackers@FreeBSD.ORG Tue Oct 10 00:40:40 2006 Return-Path: X-Original-To: freebsd-hackers@freebsd.org Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 08C1216A40F; Tue, 10 Oct 2006 00:40:40 +0000 (UTC) (envelope-from doconnor@gsoft.com.au) Received: from cain.gsoft.com.au (cain.gsoft.com.au [203.31.81.10]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5F41A43D46; Tue, 10 Oct 2006 00:40:36 +0000 (GMT) (envelope-from doconnor@gsoft.com.au) Received: from inchoate.gsoft.com.au (inchoate.gsoft.com.au [203.31.81.37]) (authenticated bits=0) by cain.gsoft.com.au (8.13.5/8.13.4) with ESMTP id k9A0eX0S018734 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 10 Oct 2006 10:10:34 +0930 (CST) (envelope-from doconnor@gsoft.com.au) From: "Daniel O'Connor" To: freebsd-hackers@freebsd.org, John-Mark Gurney Date: Tue, 10 Oct 2006 10:10:28 +0930 User-Agent: KMail/1.9.4 References: <20061009213733.GC15088@porthos.spock.org> <20061009232649.GT793@funkthat.com> In-Reply-To: <20061009232649.GT793@funkthat.com> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart3365112.JbZYhsDE0f"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <200610101010.29188.doconnor@gsoft.com.au> X-Spam-Score: -1.36 () ALL_TRUSTED X-Scanned-By: MIMEDefang 2.56 on 203.31.81.10 Cc: Jonathan Chen Subject: Re: bktr(4) risk? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 10 Oct 2006 00:40:40 -0000 --nextPart3365112.JbZYhsDE0f Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline On Tuesday 10 October 2006 08:56, John-Mark Gurney wrote: > > The only reason I can think of to use this ioctl would be if you wanted > > the image you're capturing to be directly dumped into video memory. Th= is > > This is very common... It allows the bktr driver to dump the frames > directly to the memory of your video card... This makes watching live > tv watchable... Maybe it could be restricted to the root user. In any case it's more efficient to read YUV data and then use Xv.. It=20 certainly spams the PCI bus way less, unfortunately you do become acceptabl= e=20 to load related frame drops. It would be really nice if you could connect bktr to your video card more=20 directly (instead of cap. card -> bktr -> TV app -> X server -> video card) but in practice it seems to work fine. mplayer can do this, and I have a=20 trivial app which also does it (I wrote it before mplayer grew support for= =20 bktr) =2D-=20 Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au "The nice thing about standards is that there are so many of them to choose from." -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C --nextPart3365112.JbZYhsDE0f Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (FreeBSD) iD8DBQBFKuv95ZPcIHs/zowRAjwSAJ0a3sjVUE9mDOYmRel4e1OkbpUaRgCfZQxd A3MYB3PQ37+Xrj1cmcKR0gY= =W650 -----END PGP SIGNATURE----- --nextPart3365112.JbZYhsDE0f--