Re: [ANNv4] Media Summit on May 26th in Nice, France

Jacopo Mondi
2026-04-28T12:30:58Z

Hello

On Tue, Apr 14, 2026 at 11:42:59AM +0300, Laurent Pinchart wrote:
> On Tue, Apr 14, 2026 at 10:34:13AM +0200, Loic Poulain wrote:
> > On Tue, Apr 14, 2026 at 9:42 AM Laurent Pinchart wrote:
> > > On Tue, Apr 14, 2026 at 09:20:56AM +0200, Michael Riesch wrote:
> > > > On 4/14/26 08:55, Ricardo Ribalda wrote:
> > > > > On Tue, 14 Apr 2026 at 08:47, Hans Verkuil <hverkuil+cisco@kernel.org> wrote:
> > > > >> On 13/04/2026 23:16, Laurent Pinchart wrote:
> > > > >>> On Mon, Apr 13, 2026 at 04:25:54PM -0400, Nicolas Dufresne wrote:
> > > > >>>> Le lundi 13 avril 2026 à 23:19 +0300, Laurent Pinchart a écrit :
> > > > >>>>> On Mon, Apr 13, 2026 at 10:03:52PM +0200, Loic Poulain wrote:
> > > > >>>>>> Hi Hans,
> > > > >>>>>>
> > > > >>>>>> I would be happy to discuss this if a slot is available:
> > > > >>>>>>
> > > > >>>>>> Title: Generic V4L2 ISP M2M framework
> > > > >>>>>> Presenter: Loic Poulain
> > > > >>>>>> Time estimate: ~20min
> > > > >>>>>> Description: During early development of a Qualcomm Offline Image
> > > > >>>>>> Processing Engine (OPE), we relied on the V4L2 memory‑to‑memory
> > > > >>>>>> (v4l2‑m2m) framework, which is widely used and provides solid support
> > > > >>>>>> for buffer management and scheduling. However, applying it to an ISP
> > > > >>>>>> use case exposes limitations: ISP engines often require a richer media
> > > > >>>>>> graph, with multiple pads and metadata flows, similar to inline ISP
> > > > >>>>>> pipelines (params, stats, outputs). This talk proposes discussing the
> > > > >>>>>> need for and design of a common V4L2 ISP M2M framework to factor out
> > > > >>>>>> shared functionality across drivers, particularly around buffer/queue
> > > > >>>>>> management and job scheduling.
> > > >
> > > > It seems that we share some pain points.. :-) :-/
> > > >
> > > > Over the last year, some ideas have been brewing in my mind. Not
> > > > necessarily *my* ideas, mind you, rather ideas that have been around in
> > > > linux-media for quite a while, actually. What I would like to prepare
> > > > for the Media Summit goes along the same lines.
> > > >
> > > > >>>>> That's well aligned with the v4l2-isp framework that Jacopo started, and
> > > > >>>>> to the multi-context and media-jobs APIs that we have proposed. I
> > > > >>>>> wonder, however, if a short session at the media summit will be enough,
> > > > >>>>> or if we should try to organize a half day brainstorming workshop at
> > > > >>>>> some point. Depending on when the people interested in this topic plan
> > > > >>>>> to arrive, Monday could be an option.
> > > > >>>>
> > > > >>>> I'm also/still interested in the multi-context for m2m decoders that have inline
> > > > >>>> post-processing capabilities (current model forces us to waste a lot of RAM). We
> > > > >>>> just restarted some design discussion with the team, with an increased
> > > > >>>> confidence that multi-context is the way. The scheduler could come handy in the
> > > > >>>> future if we get to deal with more multi-stage codecs in the future. I'll be in
> > > > >>>> Nice all day Monday.
> > > > >>>
> > > > >>> I will unfortunately be available only until 15:00 on Monday, but Jacopo
> > > > >>> should be available through the day. Let's see who would be interested
> > > > >>> and available, and try to organize something.
> > > > >>
> > > > >> I'm available on Monday as well. I think this is a topic that is well suited
> > > > >> to a brainstorm session.
> > > > >
> > > > > I am also available on Monday and would like to attend the session.
> > > >
> > > > I'd be interested too. Right now the plan is to arrive on Monday
> > > > afternoon. Depending on what time you agree on it may work out anyway.
> > > > It would be great to know the exact time this session will start (as I
> > > > might need to adjust my travel arrangements).
> >
> > I can arrive on Monday, with a preference for the afternoon.
> >
> > > We need a volunteer to organize this, as in finding and booking a
> > > meeting space. Note that Monday is a public holiday in France (Monday
> > > the 25th of May in particular, not all Mondays).
> > >
> > > If the number of attendees was small I was thinking of hosting the event
> > > in the place where the Ideas on Board team will be staying, but it looks
> > > like we're already reaching a fair number of people.
> > >

Are we still considering this BoF session ?

We would someone to volunteer organizing this, at @IoB we're quite
full for the week and we might have an hard time organizing this one
on top of the libcamera workshop.

As Laurent said, that Monday is a public holiday in France, and
getting a room somewhere might be complicated.

We can host some people in the location where we're having the yearly IoB
get-together, but you should arrange your travel there (35 minutes
from Nice by car).

If we get a volunteer we can should maybe a dedicated mail thread as this one
was about the Media Summit ?

> > > > > Regards!
> > > > >
> > > > >> The agenda for the media summit is getting quite full, and I agree with Laurent
> > > > >> that 20 minutes is likely not enough. If we can so a session on Monday instead,
> > > > >> then that would be a good solution.
> > > >
> > > > Apart from the time and date the scope of this session would be interesting.
> > > >
> > > > Will this be a birds of a feather session in which the next generation
> > > > kernel ISP framework will be discussed? Or even the next generation
> > > > kernel video processing framework, where video processing is image
> > > > signal processing, encoding/decoding, 2D graphics processing (fisheye
> > > > correction units, 2D GPU such as the Rockchip RGA3, ...)?
> > >
> > > I would focus on Loic's original scope. If the solution can be used for
> > > other devices that's great too. I believe that the current multi-context
> > > patch series is a good fit for codecs. If we broaden the scope too much
> > > right away we'll achieve nothing.
> > >
> > > > >> I have never been very enthusiastic about the m2m framework: it's fine for e.g.
> > > > >> simple scalers, but it's awkward to use for codecs let alone ISPs.
> > > > >>
> > > > >> I always felt that we really need variants of the m2m framework that are customized
> > > > >> to specific use-cases: i.e. a codec m2m framework, and (perhaps) an ISP m2m framework.
> > > > >>
> > > > >> The big problem with that is of course who will do the work. Making new frameworks
> > > > >> is difficult and takes a long time.
> >
> > A couple of weeks ago, I submitted an initial driver for a Qualcomm
> > Offline ISP based on the standard v4l2-m2m framework. Following
> > discussions around which parts could be generalized, I started
> > migrating this work to a new v4l2-isp-m2m framework:
> > (https://github.com/loicpoulain/linux/commit/5d575d7eff8f2371e91d8237148ffdb44b0af5b0).
>
> I definitely want to discuss this, but I will be available on Monday
> until 15:00 only.
>
> > The API and overall logic closely mirror v4l2-m2m.c, but are extended
> > to address ISP‑specific requirements such as multi‑device support and
> > multiple queue handling.
>
> That part I don't like. The V4L2 M2M framework is a big mid-layer that
> prevents drivers from having control of how operations are handled. It
> does too much, and doesn't give enough flexibility to drivers. It may
> have been fine when the framework was designed, for the devices we had
> back then, but today it's just painful. I want to turn this around and
> give control to the drivers, with helpers they can use to implement
> parts that are not driver-specific. This needs to be opt-in, not a layer
> that takes completely control between the uAPI and driver operations.
>
> Let's not reproduce the design mistakes made in the V4L2 M2M framework.
>
> I also think you need to decouple the context handling and scheduling in
> two separate components. They need to work together, but shouldn't be
> bundled into a monolithic system. Very importantly, a driver should be
> able to implement contexts with the multi-context helpers, and implement
> custom scheduling itself.
>
> > I am planning to submit this work as an RFC
> > before the Media Summit. At this stage, the framework is still fairly
> > basic and primarily tailored to the Qualcomm use case. There is
> > definitely room for improvement, for example, integrating Jacopo’s
> > multi‑context support, since for now, the Qualcomm driver simply
> > instantiates a single ISP‑M2M context.
> >
> > As I am still getting familiar with the media subsystem, this work may
> > overlap with or conflict with ongoing efforts. Synchronizing seems
> > indeed important. Based on my current understanding, there are several
> > related areas of work that appear either complementary or orthogonal:
> > - Multi‑context support, to instantiate multiple processing sessions
> > on shared hardware/driver.
> > - Media jobs, to synchronize work across multiple drivers within the
> > same media pipeline.
> > - ISP M2M, aiming to provide a v4l2-m2m‑like framework specifically
> > for memory‑to‑memory ISP devices.
> >
> > > > This may be naive and overly optimistic, but I feel there is quite a
> > > > number of people sharing the same pain points (which are similar to
> > > > those Loic pointed out). Maybe (hopefully) this birds of a feather
> > > > session leads to the formation of some work group?
> > > >
> > > > >>>>>> On Sun, Apr 12, 2026 at 12:25 PM Hans Verkuil wrote:
> > > > >>>>>>>
> > > > >>>>>>> (Please pass this on to anyone you think might be interested in this!)
> > > > >>>>>>>
> > > > >>>>>>> Hi all,
> > > > >>>>>>>
> > > > >>>>>>> This is the fourth version of this announcement, updating the list of attendees
> > > > >>>>>>> and the tentative agenda at the end: please let me know if you see mistakes.
> > > > >>>>>>> Note that there is still time for one or two other topics. Also please check
> > > > >>>>>>> the agenda if you need more (or perhaps less) time for your topic.
> > > > >>>>>>>
> > > > >>>>>>> This year's Media Summit will be held on Tuesday May 26th the day before the
> > > > >>>>>>> Embedded Recipes Conference in Nice, France:
> > > > >>>>>>>
> > > > >>>>>>> https://embedded-recipes.org/2026/
> > > > >>>>>>>
> > > > >>>>>>> The Media Summit will be held at Hotel Campanile and in the same meeting room
> > > > >>>>>>> as last year (Nikaia):
> > > > >>>>>>>
> > > > >>>>>>> https://nice-aeroport.campanile.com/en-us/
> > > > >>>>>>>
> > > > >>>>>>> It is close to the Airport and to the Embedded Recipes venue.
> > > > >>>>>>>
> > > > >>>>>>> The meeting room can hold up to 30 people and I will provide video conferencing support,
> > > > >>>>>>> just like last year. The location and the meeting room was quite nice last year, so
> > > > >>>>>>> I saw no need to change it.
> > > > >>>>>>>
> > > > >>>>>>> That said, in-person participation is very much preferred. This yearly summit is meant
> > > > >>>>>>> for active media developers to meet face-to-face and to discuss media subsystem issues.
> > > > >>>>>>>
> > > > >>>>>>> And it is also a good opportunity to talk to each other during the Embedded Recipes
> > > > >>>>>>> conference to discuss topics in a smaller group. But if you are an active media developer
> > > > >>>>>>> and are really not able to attend in person, then remote participation is an option.
> > > > >>>>>>>
> > > > >>>>>>> If you want to attend the meeting (either in person or remote), then send an email to me
> > > > >>>>>>> directly. The deadline for in-person attendance is May 14 as the hotel needs to know the
> > > > >>>>>>> final number of attendees by then.
> > > > >>>>>>>
> > > > >>>>>>> There is no registration fee, the meeting room is sponsored by Cisco and Collabora, and
> > > > >>>>>>> the lunch is sponsored by Ideas on Board! Many thanks to our sponsors, it's very much
> > > > >>>>>>> appreciated.
> > > > >>>>>>>
> > > > >>>>>>> If you have a topic that you want to discuss, just 'Reply All' to this announcement
> > > > >>>>>>> and give the topic title, a short description and a guesstimate of the time you need
> > > > >>>>>>> for your topic.
> > > > >>>>>>>
> > > > >>>>>>> See last year's Media Summit Report as an example of what to expect:
> > > > >>>>>>>
> > > > >>>>>>> https://lore.kernel.org/linux-media/21769183-ca57-4f8f-818a-6a1ad089298d@jjverkuil.nl/
> > > > >>>>>>>
> > > > >>>>>>> Regards,
> > > > >>>>>>>
> > > > >>>>>>> Hans
> > > > >>>>>>>
> > > > >>>>>>> PS: Be aware that May 24 and 25 are public holidays in France. So many
> > > > >>>>>>> shops may be
> > > > >>>>>>> closed those days.
> > > > >>>>>>>
> > > > >>>>>>> In-person attendees:
> > > > >>>>>>> Sakari Ailus <sakari.ailus@linux.intel.com>
> > > > >>>>>>> Kieran Bingham <kieran.bingham@ideasonboard.com>
> > > > >>>>>>> Brandon Brnich <b-brnich@ti.com>
> > > > >>>>>>> Rouven Czerwinski <rouven.czerwinski@linaro.org>
> > > > >>>>>>> Mehdi Djait <mehdi.djait@linux.intel.com>
> > > > >>>>>>> Bryan O'Donoghue <bryan.odonoghue@linaro.org>
> > > > >>>>>>> Nicolas Dufresne <nicolas.dufresne@collabora.com>
> > > > >>>>>>> Marco Felsch <m.felsch@pengutronix.de>
> > > > >>>>>>> Paul Kocialkowski <paulk@sys-base.io>
> > > > >>>>>>> Jai Luthra <jai.luthra@ideasonboard.com>
> > > > >>>>>>> Jacopo Mondi <jacopo.mondi@ideasonboard.com>
> > > > >>>>>>> Benjamin Mugnier <benjamin.mugnier@foss.st.com>
> > > > >>>>>>> Beleswar Padhi <b-padhi@ti.com>
> > > > >>>>>>> Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > > > >>>>>>> Loic Poulain <loic.poulain@oss.qualcomm.com>
> > > > >>>>>>> Sven Püschel <s.pueschel@pengutronix.de>
> > > > >>>>>>> Ricardo Ribalda <ribalda@chromium.org>
> > > > >>>>>>> Michael Riesch <michael.riesch@collabora.com>
> > > > >>>>>>> Devarsh Thakkar <devarsht@ti.com>
> > > > >>>>>>> Michael Tretter <m.tretter@pengutronix.de>
> > > > >>>>>>> Hans Verkuil <hverkuil@kernel.org>
> > > > >>>>>>>
> > > > >>>>>>> Remote attendees:
> > > > >>>>>>> Yemike Abhilash Chandra <y-abhilashchandra@ti.com>
> > > > >>>>>>> Rishikesh Donadkar <r-donadkar@ti.com>
> > > > >>>>>>> Jackson Lee <jackson.lee@chipsnmedia.com>
> > > > >>>>>>> Dave Stevenson <dave.stevenson@raspberrypi.com> (tentative)
> > > > >>>>>>>
> > > > >>>>>>>
> > > > >>>>>>> Agenda (tentative):
> > > > >>>>>>>
> > > > >>>>>>> 8:45-9:20: Arrive, settle in
> > > > >>>>>>>
> > > > >>>>>>> 9:20-9:30: Short intro (Hans Verkuil)
> > > > >>>>>>>
> > > > >>>>>>> 9:30-9:45: Status of ISP support in V4L2
> > > > >>>>>>> Presenter: Laurent Pinchart
> > > > >>>>>>> Description: Summary of ISP-related development in V4L2 since the last
> > > > >>>>>>> Linux Media Summit. This includes a brief overview of technical
> > > > >>>>>>> developments, and a summary of the efforts to engage with vendors.
> > > > >>>>>>>
> > > > >>>>>>> 9:45-10:45: V4L2 Stateless Video Encoding uAPI Progress Update
> > > > >>>>>>> Presenter: Paul Kocialkowski
> > > > >>>>>>> Description: An update on the ongonig work to support stateless codecs in V4L2.
> > > > >>>>>>> Some of the remaining open topics will be presented and discussed.
> > > > >>>>>>>
> > > > >>>>>>> 10:45-11:00: break
> > > > >>>>>>>
> > > > >>>>>>> 11:00-11:30: Vulkan Video Codecs
> > > > >>>>>>> Presenter: Nicolas Dufresne
> > > > >>>>>>> Description: Vulkan video codecs: what are the viable options for Linux Media
> > > > >>>>>>> and what is in preparation outside of our subsystem. The second aspect is
> > > > >>>>>>> informative as these discussions don't seem to lean toward our subsystem as the
> > > > >>>>>>> foundation. But I think it's rather useful for everyone to understand why and
> > > > >>>>>>> what is included.
> > > > >>>>>>>
> > > > >>>>>>> 11:30-12:00: Protected Video playback on i.MX8MQ
> > > > >>>>>>> Presenter: Rouven Czerwinski
> > > > >>>>>>> Description: Introduction to protected video playback
> > > > >>>>>>> on i.MX8MQ and missing bits for linux-media & protected heap interoperability.
> > > > >>>>>>>
> > > > >>>>>>> 12:00-13:30: Lunch
> > > > >>>>>>>
> > > > >>>>>>> 13:30-14:00: HDCP support for HDMI receivers
> > > > >>>>>>> Presenter: Hans Verkuil
> > > > >>>>>>> Description: I have been working on adding HDCP support for HDMI receivers.
> > > > >>>>>>> Specifically the HDCP negotiation between sources and sinks.
> > > > >>>>>>>
> > > > >>>>>>> 14:00-14:30: AI patches
> > > > >>>>>>> Presenter: Sakari Ailus
> > > > >>>>>>> Description: What is our policy w.r.t. AI generated patches?
> > > > >>>>>>>
> > > > >>>>>>> 14:30-15:00 Overview of Media CI: where do pipelines run?
> > > > >>>>>>> Presenter: Ricardo Ribalda
> > > > >>>>>>> Description: How are jobs in pipelines assigned? How does the infrastructure
> > > > >>>>>>> for Media CI work? Are there things that can be tweaked to make it more
> > > > >>>>>>> reliable?
> > > > >>>>>>>
> > > > >>>>>>> 15:00-15:15: Break
> > > > >>>>>>>
> > > > >>>>>>> 15:15-16:15: Discussion of the media subsystem development process
> > > > >>>>>>> Presenter: Hans Verkuil
> > > > >>>>>>> Description: Review of the multi-committer model: current status and next steps.
> > > > >>>>>>> Are there any bottlenecks, any ideas for improvements, w.r.t. the development process?
> > > > >>>>>>>
> > > > >>>>>>> As you can see, there is still some available time for other topics.
>
> --
> Regards,
>
> Laurent Pinchart