From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from bhuna.collabora.co.uk ([93.93.135.160]:52335 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751826AbbJDXPP (ORCPT ); Sun, 4 Oct 2015 19:15:15 -0400 Message-ID: <1444000510.26489.4.camel@collabora.com> Subject: Re: v4l2 api: supported resolution negotiation From: Nicolas Dufresne Reply-To: Nicolas Dufresne To: Sakari Ailus , "Matwey V. Kornilov" Cc: linux-media@vger.kernel.org Date: Mon, 05 Oct 2015 00:15:10 +0100 In-Reply-To: <20151004184923.GH26916@valkosipuli.retiisi.org.uk> References: <20151004184923.GH26916@valkosipuli.retiisi.org.uk> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-hzoCk09FxsH2V1UbXGyY" Mime-Version: 1.0 Sender: linux-media-owner@vger.kernel.org List-ID: --=-hzoCk09FxsH2V1UbXGyY Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Le dimanche 04 octobre 2015 =C3=A0 21:49 +0300, Sakari Ailus a =C3=A9crit : > I think the GStreamer > v4lsrc tries very small and very large values. The driver will clamp > them to > a supported values which are passed to the application from the > IOCTL. In GStreamer we try ENUM_FRAMESIZE, and when no supported, we fallback to try_fmt() with 1x1 (driver will raise it to the minimum) and then MAX,MAX (driver will lower it to the maximum). We assume that the driver supports a range, as iterating over all possibilities takes too much time. Nicolas --=-hzoCk09FxsH2V1UbXGyY Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEABECAAYFAlYRsv4ACgkQcVMCLawGqByZZgCfe7p+fVc8U1roa3/Q4Gh75jpq 8asAn2bvg+Tew3kEEkvXWgmqPJSEv96b =bcQU -----END PGP SIGNATURE----- --=-hzoCk09FxsH2V1UbXGyY--