From patchwork Tue Sep 18 09:34:19 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Philipp Zabel X-Patchwork-Id: 10603901 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A65FE15E8 for ; Tue, 18 Sep 2018 09:34:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 981C02A116 for ; Tue, 18 Sep 2018 09:34:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8C6612A11A; Tue, 18 Sep 2018 09:34:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 360F62A12B for ; Tue, 18 Sep 2018 09:34:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729670AbeIRPGb (ORCPT ); Tue, 18 Sep 2018 11:06:31 -0400 Received: from metis.ext.pengutronix.de ([85.220.165.71]:58173 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729647AbeIRPGa (ORCPT ); Tue, 18 Sep 2018 11:06:30 -0400 Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7] helo=dude.pengutronix.de.) by metis.ext.pengutronix.de with esmtp (Exim 4.89) (envelope-from ) id 1g2COz-00033v-1n; Tue, 18 Sep 2018 11:34:37 +0200 From: Philipp Zabel To: linux-media@vger.kernel.org, Steve Longerbeam Cc: Nicolas Dufresne , kernel@pengutronix.de Subject: [PATCH v3 14/16] gpu: ipu-v3: image-convert: add some ASCII art to the exposition Date: Tue, 18 Sep 2018 11:34:19 +0200 Message-Id: <20180918093421.12930-15-p.zabel@pengutronix.de> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20180918093421.12930-1-p.zabel@pengutronix.de> References: <20180918093421.12930-1-p.zabel@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: p.zabel@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-media@vger.kernel.org Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Visualize the scaling and rotation pipeline with some ASCII art diagrams. Remove the FIXME comment about missing seam prevention. Signed-off-by: Philipp Zabel --- No changes since v2. --- drivers/gpu/ipu-v3/ipu-image-convert.c | 39 +++++++++++++++++++------- 1 file changed, 29 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/ipu-v3/ipu-image-convert.c b/drivers/gpu/ipu-v3/ipu-image-convert.c index 16d400b2b3d2..6179d8bd123c 100644 --- a/drivers/gpu/ipu-v3/ipu-image-convert.c +++ b/drivers/gpu/ipu-v3/ipu-image-convert.c @@ -37,17 +37,36 @@ * when double_buffering boolean is set). * * Note that the input frame must be split up into the same number - * of tiles as the output frame. + * of tiles as the output frame: * - * FIXME: at this point there is no attempt to deal with visible seams - * at the tile boundaries when upscaling. The seams are caused by a reset - * of the bilinear upscale interpolation when starting a new tile. The - * seams are barely visible for small upscale factors, but become - * increasingly visible as the upscale factor gets larger, since more - * interpolated pixels get thrown out at the tile boundaries. A possilble - * fix might be to overlap tiles of different sizes, but this must be done - * while also maintaining the IDMAC dma buffer address alignment and 8x8 IRT - * alignment restrictions of each tile. + * +---------+-----+ + * +-----+---+ | A | B | + * | A | B | | | | + * +-----+---+ --> +---------+-----+ + * | C | D | | C | D | + * +-----+---+ | | | + * +---------+-----+ + * + * Clockwise 90° rotations are handled by first rescaling into a + * reusable temporary tile buffer and then rotating with the 8x8 + * block rotator, writing to the correct destination: + * + * +-----+-----+ + * | | | + * +-----+---+ +---------+ | C | A | + * | A | B | | A,B, | | | | | + * +-----+---+ --> | C,D | | --> | | | + * | C | D | +---------+ +-----+-----+ + * +-----+---+ | D | B | + * | | | + * +-----+-----+ + * + * If the 8x8 block rotator is used, horizontal or vertical flipping + * is done during the rotation step, otherwise flipping is done + * during the scaling step. + * With rotation or flipping, tile order changes between input and + * output image. Tiles are numbered row major from top left to bottom + * right for both input and output image. */ #define MAX_STRIPES_W 4