From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pali =?utf-8?B?Um9ow6Fy?= Subject: Re: support autofocus / autogain in libv4l2 Date: Tue, 25 Apr 2017 10:08:15 +0200 Message-ID: <20170425080815.GD30553@pali> References: <1487074823-28274-1-git-send-email-sakari.ailus@linux.intel.com> <1487074823-28274-2-git-send-email-sakari.ailus@linux.intel.com> <20170414232332.63850d7b@vento.lan> <20170416091209.GB7456@valkosipuli.retiisi.org.uk> <20170419105118.72b8e284@vento.lan> <20170424093059.GA20427@amd> <20170424103802.00d3b554@vento.lan> <20170424212914.GA20780@amd> <20170424224724.5bb52382@vento.lan> <20170425080538.GA30380@amd> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Disposition: inline In-Reply-To: <20170425080538.GA30380@amd> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Pavel Machek Cc: ivo.g.dimitrov.75@gmail.com, linux-media@vger.kernel.org, khilman@kernel.org, tony@atomide.com, aaro.koskinen@iki.fi, sre@kernel.org, kernel list , Mauro Carvalho Chehab , abcloriens@gmail.com, Sakari Ailus , Sakari Ailus , linux-omap@vger.kernel.org, patrikbachan@gmail.com, linux-arm-kernel , serge@hallyn.com List-Id: linux-omap@vger.kernel.org T24gVHVlc2RheSAyNSBBcHJpbCAyMDE3IDEwOjA1OjM4IFBhdmVsIE1hY2hlayB3cm90ZToKPiA+ ID4gSXQgd291bGQgYmUgbmljZSBpZiBtb3JlIHRoYW4gb25lIGFwcGxpY2F0aW9uIGNvdWxkIGJl IGFjY2Vzc2luZyB0aGUKPiA+ID4gY2FtZXJhIGF0IHRoZSBzYW1lIHRpbWUuLi4gKEkuZS4gc29t ZXRoaW5nIGdyYXBoaWNhbCBydW5uaW5nIHByZXZpZXcKPiA+ID4gdGhlbiB1c2luZyBjb21tYW5k IGxpbmUgdG9vbCB0byBncmFiIGEgcGljdHVyZS4pIFRoaXMgb25lIGlzCj4gPiA+IGRlZmluaXRl bHkgbm90IHNvbHZlYWJsZSBpbnNpZGUgYSBsaWJyYXJ5Li4uCj4gPiAKPiA+IFNvbWVvbmUgb25j ZSBzdWdnZXN0ZWQgdG8gaGF2ZSBzb21ldGhpbmcgbGlrZSBwdWxzZWF1ZGlvIGZvciBWNEwuCj4g PiBGb3Igc3VjaCB1c2FnZSwgYSBzZXJ2ZXIgd291bGQgYmUgaW50ZXJlc3RpbmcuIFlldCwgSSB3 b3VsZCBjb2RlIGl0Cj4gPiBpbiBhIHdheSB0aGF0IGFwcGxpY2F0aW9ucyB1c2luZyBsaWJ2NGwg d2lsbCB0YWxrIHdpdGggc3VjaCBkYWVtb24KPiA+IGluIGEgdHJhbnNwYXJlbnQgd2F5Lgo+IAo+ IFllcywgd2UgbmVlZCBzb21ldGhpbmcgbGlrZSBwdWxzZWF1ZGlvIGZvciBWNEwuIEFuZCB5ZXMs IHdlIHNob3VsZAo+IG1ha2UgaXQgdHJhbnNwYXJlbnQgZm9yIGFwcGxpY2F0aW9ucyB1c2luZyBs aWJ2NGwuCgpJSVJDIHRoZXJlIGlzIGFscmVhZHkgc29tZSBlZmZvcnQgaW4gd3JpdGluZyBzdWNo ICJ2aWRlbyIgc2VydmVyIHdoaWNoCndvdWxkIHN1cHBvcnQgYWNjZXNzaW5nIG1vcmUgYXBwbGlj YXRpb24gaW50byB3ZWJjYW0gdmlkZW8sIGxpa2UKcHVsc2VhdWRpbyBzZXJ2ZXIgZm9yIGFjY2Vz c2luZyBtb3JlIGFwcGxpY2F0aW9ucyB0byBtaWNyb3Bob25lIGlucHV0LgoKLS0gClBhbGkgUm9o w6FyCnBhbGkucm9oYXJAZ21haWwuY29tCgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fXwpsaW51eC1hcm0ta2VybmVsIG1haWxpbmcgbGlzdApsaW51eC1hcm0t a2VybmVsQGxpc3RzLmluZnJhZGVhZC5vcmcKaHR0cDovL2xpc3RzLmluZnJhZGVhZC5vcmcvbWFp bG1hbi9saXN0aW5mby9saW51eC1hcm0ta2VybmVsCg== From mboxrd@z Thu Jan 1 00:00:00 1970 From: pali.rohar@gmail.com (Pali =?utf-8?B?Um9ow6Fy?=) Date: Tue, 25 Apr 2017 10:08:15 +0200 Subject: support autofocus / autogain in libv4l2 In-Reply-To: <20170425080538.GA30380@amd> References: <1487074823-28274-1-git-send-email-sakari.ailus@linux.intel.com> <1487074823-28274-2-git-send-email-sakari.ailus@linux.intel.com> <20170414232332.63850d7b@vento.lan> <20170416091209.GB7456@valkosipuli.retiisi.org.uk> <20170419105118.72b8e284@vento.lan> <20170424093059.GA20427@amd> <20170424103802.00d3b554@vento.lan> <20170424212914.GA20780@amd> <20170424224724.5bb52382@vento.lan> <20170425080538.GA30380@amd> Message-ID: <20170425080815.GD30553@pali> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tuesday 25 April 2017 10:05:38 Pavel Machek wrote: > > > It would be nice if more than one application could be accessing the > > > camera at the same time... (I.e. something graphical running preview > > > then using command line tool to grab a picture.) This one is > > > definitely not solveable inside a library... > > > > Someone once suggested to have something like pulseaudio for V4L. > > For such usage, a server would be interesting. Yet, I would code it > > in a way that applications using libv4l will talk with such daemon > > in a transparent way. > > Yes, we need something like pulseaudio for V4L. And yes, we should > make it transparent for applications using libv4l. IIRC there is already some effort in writing such "video" server which would support accessing more application into webcam video, like pulseaudio server for accessing more applications to microphone input. -- Pali Roh?r pali.rohar at gmail.com From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-wm0-f66.google.com ([74.125.82.66]:35657 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1176422AbdDYIIT (ORCPT ); Tue, 25 Apr 2017 04:08:19 -0400 Date: Tue, 25 Apr 2017 10:08:15 +0200 From: Pali =?utf-8?B?Um9ow6Fy?= To: Pavel Machek Cc: Mauro Carvalho Chehab , sre@kernel.org, kernel list , linux-arm-kernel , linux-omap@vger.kernel.org, tony@atomide.com, khilman@kernel.org, aaro.koskinen@iki.fi, ivo.g.dimitrov.75@gmail.com, patrikbachan@gmail.com, serge@hallyn.com, abcloriens@gmail.com, Sakari Ailus , Sakari Ailus , linux-media@vger.kernel.org Subject: Re: support autofocus / autogain in libv4l2 Message-ID: <20170425080815.GD30553@pali> References: <1487074823-28274-1-git-send-email-sakari.ailus@linux.intel.com> <1487074823-28274-2-git-send-email-sakari.ailus@linux.intel.com> <20170414232332.63850d7b@vento.lan> <20170416091209.GB7456@valkosipuli.retiisi.org.uk> <20170419105118.72b8e284@vento.lan> <20170424093059.GA20427@amd> <20170424103802.00d3b554@vento.lan> <20170424212914.GA20780@amd> <20170424224724.5bb52382@vento.lan> <20170425080538.GA30380@amd> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20170425080538.GA30380@amd> Sender: linux-media-owner@vger.kernel.org List-ID: On Tuesday 25 April 2017 10:05:38 Pavel Machek wrote: > > > It would be nice if more than one application could be accessing the > > > camera at the same time... (I.e. something graphical running preview > > > then using command line tool to grab a picture.) This one is > > > definitely not solveable inside a library... > > > > Someone once suggested to have something like pulseaudio for V4L. > > For such usage, a server would be interesting. Yet, I would code it > > in a way that applications using libv4l will talk with such daemon > > in a transparent way. > > Yes, we need something like pulseaudio for V4L. And yes, we should > make it transparent for applications using libv4l. IIRC there is already some effort in writing such "video" server which would support accessing more application into webcam video, like pulseaudio server for accessing more applications to microphone input. -- Pali Rohár pali.rohar@gmail.com