From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from ni.piap.pl ([195.187.100.4]:45074 "EHLO ni.piap.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752135AbeFFFsv (ORCPT ); Wed, 6 Jun 2018 01:48:51 -0400 From: khalasa@piap.pl (Krzysztof =?utf-8?Q?Ha=C5=82asa?=) To: Steve Longerbeam Cc: Philipp Zabel , Steve Longerbeam , Mauro Carvalho Chehab , Greg Kroah-Hartman , Hans Verkuil , Subject: Re: [PATCH v2 04/10] media: imx: interweave only for sequential input/interlaced output fields References: <1527813049-3231-1-git-send-email-steve_longerbeam@mentor.com> <1527813049-3231-5-git-send-email-steve_longerbeam@mentor.com> <1527860010.5913.8.camel@pengutronix.de> <1528100849.5808.2.camel@pengutronix.de> <1528186075.4074.1.camel@pengutronix.de> <98b3cd1e-32ff-e7bb-b2ba-7b622aa983b6@mentor.com> Date: Wed, 06 Jun 2018 07:48:48 +0200 In-Reply-To: <98b3cd1e-32ff-e7bb-b2ba-7b622aa983b6@mentor.com> (Steve Longerbeam's message of "Tue, 5 Jun 2018 12:00:52 -0700") Message-ID: MIME-Version: 1.0 Content-Type: text/plain Sender: linux-media-owner@vger.kernel.org List-ID: Steve Longerbeam writes: > I don't follow you, yes the interweaving step only has access to > a single frame, but why would interweave need access to another > frame to carry out seq-bt -> interlaced-tb ? See below... You can't to that. You can delay the input stream (skip one field) so the bottom-first becomes top-first (or top-first - bottom-first), probably with some loss of chroma quality, but you can't reorder odd and even lines. To convert (anything)-bt -> (anything)-tb you need two consecutive fields, the top one and then the bottom one. If the input is *-bt, this means two "frames" (if the word "frame" is applicable at this point). CCIR_CODE_* registers are fine, though. They don't change the geometry, the just skip a single field (sort of, actually they sync to the required field). -- Krzysztof Halasa Industrial Research Institute for Automation and Measurements PIAP Al. Jerozolimskie 202, 02-486 Warsaw, Poland