From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from perceval.ideasonboard.com ([213.167.242.64]:46738 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729240AbeJASZT (ORCPT ); Mon, 1 Oct 2018 14:25:19 -0400 From: Laurent Pinchart To: Hans Verkuil Cc: Linux Media Mailing List Subject: Re: [RFC] V4L2_PIX_FMT_MJPEG vs V4L2_PIX_FMT_JPEG Date: Mon, 01 Oct 2018 14:48:10 +0300 Message-ID: <2438028.OjeO6a9KTA@avalon> In-Reply-To: <03c10b29-6ead-1aa2-334a-c6357004a5ac@xs4all.nl> References: <03c10b29-6ead-1aa2-334a-c6357004a5ac@xs4all.nl> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-media-owner@vger.kernel.org List-ID: Hi Hans, On Monday, 1 October 2018 11:43:04 EEST Hans Verkuil wrote: > It turns out that we have both JPEG and Motion-JPEG pixel formats defined. > > Furthermore, some drivers support one, some the other and some both. > > These pixelformats both mean the same. Do they ? I thought MJPEG was JPEG using fixed Huffman tables that were not included in the JPEG headers. > I propose that we settle on JPEG (since it seems to be used most often) and > add JPEG support to those drivers that currently only use MJPEG. > > We also need to update the V4L2_PIX_FMT_JPEG documentation since it just > says TBD: > > https://www.linuxtv.org/downloads/v4l-dvb-apis-new/uapi/v4l/pixfmt-compresse > d.html > > $ git grep -l V4L2_PIX_FMT_MJPEG > drivers/media/pci/meye/meye.c > drivers/media/pci/solo6x10/solo6x10-v4l2-enc.c > drivers/media/platform/sti/delta/delta-cfg.h > drivers/media/platform/sti/delta/delta-mjpeg-dec.c > drivers/media/usb/cpia2/cpia2_v4l.c > drivers/media/usb/go7007/go7007-driver.c > drivers/media/usb/go7007/go7007-fw.c > drivers/media/usb/go7007/go7007-v4l2.c > drivers/media/usb/s2255/s2255drv.c > drivers/media/usb/uvc/uvc_driver.c > drivers/staging/media/zoran/zoran_driver.c > drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c > drivers/usb/gadget/function/uvc_v4l2.c > > It looks like s2255 and cpia2 support both already, so that would leave > 8 drivers that need to be modified, uvc being the most important of the > lot. > > Any comments? -- Regards, Laurent Pinchart