From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 076342248A8; Tue, 3 Feb 2026 21:49:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770155392; cv=none; b=Nw9eSl27NxeGuMvQBwD9VQEe9Zng1zRJK+A7ZoxJBGVwpTPCcqqhiLgn8RNj6PUvvhgbwkrA2D6V/4TEqSD2Ke9zvR/nMqyL2TtQhNxMHT/C/Q0PGW3j3XlhDTUd6Ljvz99e0IJtZOjLlkCPa/NGaMraTdYZQ7BMJEaOJcJF1KM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770155392; c=relaxed/simple; bh=vD1zxLgAabWQHbeuPBzsULAz9TNwxWyZwXi+eq9QzW4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=GIJt4zVGPtEfXuPVSm6wYhYMc0k3C06eGCB+6PbkFHg65cTRU+YmsX4BLWJsUWUERSozRzBhl6gXLQHxPaTJirqr4moLc4A815FuQBNAzqwH7bKsDsAGcMfmc9XNOWmlj2CJWDP1vPPaznc8HzLmvBxHtSnourYI+vNVeYbReJ4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=XN+KRGGy; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="XN+KRGGy" Received: from killaraus.ideasonboard.com (2001-14ba-703d-e500--2a1.rev.dnainternet.fi [IPv6:2001:14ba:703d:e500::2a1]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 98286673; Tue, 3 Feb 2026 22:49:07 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1770155347; bh=vD1zxLgAabWQHbeuPBzsULAz9TNwxWyZwXi+eq9QzW4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=XN+KRGGyHqGPLexS58AFbgipNPkpOBPM2Rwm3u5GaL/NLPbJV+z0NI203To47JTG1 QPSIFINn8rZtR5YX2xniFh1pM0aANzBNV2jGVyGvE3SGqzlLKCnRTACi1EDbRVvu+L mttpVJqqwzLAnL5CAEMcZAqKuIwuyejHiCLr7LP8= Date: Tue, 3 Feb 2026 23:49:47 +0200 From: Laurent Pinchart To: Oleksandr Natalenko Cc: Gergo Koteles , Mauro Carvalho Chehab , Jarkko Sakkinen , linux-media@vger.kernel.org, jani.nikula@linux.intel.com, anisse@astier.eu, Mauro Carvalho Chehab , Hans Verkuil , Sakari Ailus , Jacopo Mondi , Ricardo Ribalda , open list , Nicolas Dufresne Subject: Re: [RFC PATCH] media: Virtual camera driver Message-ID: <20260203214947.GA133801@killaraus> References: <20260201133342.335680-1-jarkko@kernel.org> <20260203145341.GB33304@killaraus> <20260203203648.GA56480@killaraus> <6235268.lOV4Wx5bFT@natalenko.name> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <6235268.lOV4Wx5bFT@natalenko.name> On Tue, Feb 03, 2026 at 10:39:41PM +0100, Oleksandr Natalenko wrote: > On úterý 3. února 2026 21:36:48, středoevropský standardní čas Laurent Pinchart wrote: > > On Tue, Feb 03, 2026 at 04:53:41PM +0200, Laurent Pinchart wrote: > > > On Tue, Feb 03, 2026 at 03:38:06PM +0100, Oleksandr Natalenko wrote: > > > > > > > > Just to share my current state of affairs: > > > > > > > > * sender: > > > > > > > > $ gst-launch-1.0 pipewiresrc path= ! video/x-h264, width=1280, height=720, framerate=24/1 ! rtph264pay ! rtpstreampay ! udpsink host= port= > > > > > > > > * receiver: > > > > > > > > $ gst-launch-1.0 udpsrc address= port= ! queue ! application/x-rtp-stream,encoding-name=H264 ! rtpstreamdepay ! application/x-rtp,encoding-name=H264 ! rtph264depay ! h264parse ! openh264dec ! pipewiresink mode=provide stream-properties="properties,media.class=Video/Source,media.role=Camera" client-name=VirtualCam > > > > > > > > I chose H.264 because of much lower (tenfold) traffic comparing to > > > > MJPEG, wrapped this into RTP, opted in for OpenH264 decoder because I > > > > read it was handling low latency streams better than avdec_h264, and > > > > tested this setup with both Firefox and Chromium, and it actually > > > > worked pretty reliably, so I'm impressed now. > > > > > > Thank you for the update. I'll give this a try. > > > > I've tried those, but as soon as Firefox is connecting, I get > > > > 0:00:03.569028999 131465 0x7f85cc002030 DEBUG pipewiresink gstpipewiresink.c:692:on_state_changed: got stream state "error" (-1) > > 0:00:03.569060959 131465 0x7f85cc002030 DEBUG pipewiresink gstpipewiresink.c:692:on_state_changed: got stream state "error" (-1) > > 0:00:03.569070767 131465 0x7f85cc002030 WARN pipewiresink gstpipewiresink.c:710:on_state_changed: error: stream error: no more input formats > > ERROR: from element /GstPipeline:pipeline0/GstPipeWireSink:pipewiresink0: stream error: no more input formats > > Additional debug info: > > ../pipewire-1.4.9/src/gst/gstpipewiresink.c(710): on_state_changed (): /GstPipeline:pipeline0/GstPipeWireSink:pipewiresink0 > > > > Maybe I should try the pipewire master branch. > > I'd be glad to help, but my understanding of this "stream error: no > more input formats" boils down only to the absence of caps identifiers > (like those "application/x-rtp-stream"blahblah), which is not the case > here. Also, Firefox behaves differently from Chrome when using sites > like webcamtests, and also when using google meet. I may speculate > Firefox more eagerly closes link to a pipewire node, but I have no > knowledge of this at all. No worries. I'll try to find time to investigate. > That said, "pretty reliably" doesn't mean without issues whatsoever, > and I manage to crash both Chrome and Firefox from time to time while > experimenting with pipelines. Probably because I occasionally > unintentionally feed some crap into the pipewire sink. I wouldn't dare claiming it's perfect :-) But the projects are actively developed, so I have good hopes issues will be fixed quickly (as long as they're reported of course). > FWIW, I'm using 1:1.4.10-2 pipewire packages from Arch. I'm running 1.4.9 from Gentoo, I think I should upgrade. -- Regards, Laurent Pinchart