Tuesday, November 12, 2019

ELCE in Lyon 2019

I went to the ELCE conference that took place in Lyon during 28-30th of October 2019.
A day before the conference, the outreachy inters and mentors were invited to a dinner in a pizza restaurant. There I met my mentor Hans Verkuil for the first time.
I slept in an Airbnb apartment by myself during the conference time, just a few minutes walk from the main train station Gare de Lyon-Part-Dieu. This was comfortable since it is not too far from the conference place and also there is a direct shuttel from there to the airport. As I arrived to the conference at the first day, I got the badge with my name and background (Outrachy intern) and some goodies like 3 day tickets for transportation, a voucher for wine or beer, voucher for the talkers dinner and a T-shirt. The main hall, where all the booths were was pretty huge and was crowded all the time. There were small croissant served in the mornings and coffee and fruits served all day.
I was in the conference with many of my colleagues from Collabora which I met for the first time just a week before during a company meeting in Nice. We had a Collabora booth there where people could play SuperTuxKart on a RK3399 SoC. I came to the conference officially as an Outreachy allumi intern and also gave a 5 min talk about my internship project.
There were talks in the conference all they long about various subjects. I found it hard to understand technical talks if I don't have enough background. So for example I went to a talk about u-boot and a talk about the GPU Linux subsystem, and I felt was just setting there warming the chair.
The conference is an opportunity for the developers to meet face to face as they are in many cases spread around the world. The v4l community held several discussions. I went to a discussion about codecs and about libcamera. The discussions are long and not always easy to follow. I remember for example a discussion about what should be the behavior of a decoder driver if at some point during the decoding, the initial allocated buffers are not big enough to contain the decoded frame. There are several ways to deal with it. Some questions that arise: Should the driver inform the userspace about it? Should it be the userspace responsibility to stop the streaming and allocate new buffers? Also, is it possible to track at which frame it happened and try to decode it again?
The other discussion was about libcamera. Libcamera is a a userspace library that supplies an API for applications to interact with cameras. At the second day of the conference there was a talk on libcamera by Jacopo Mondi where he showed through live coding how applications should use the API. The project, lead by Laurent Pinchart is one year old and is entering API stabilization phase. The libcamera discussion was held in the morning after the talk and people interested in it could ask questions.
At the very end of the conference there was a game where at each round two facts related to Linux / Computers are given and the people should decide which of them is correct. Then after that there was a scissors paper rock game against the host. I failed very badly in both games.

After the conference was over I stayed two more days in the Lyon, I found a nice coworking space 'Le 18 Coworking' where I worked from.
Those were two rainy days and the second of them was apparently a holiday in France called All Saints’ Day.