The pandemic was a bit of a mess for most FLOSS conferences. The two conferences that I help organize -- FOSDEM and DebConf -- are no exception. In both conferences, I do essentially the same work: as a member of both video teams, I manage the postprocessing of the video recordings of all the talks that happened at the respective conference(s). I do this by way of SReview, the online video review and transcode system that I wrote, which essentially crowdsources the manual work that needs to be done, and automates as much as possible of the workflow.

The original version of SReview consisted of a database, a (very basic) Mojolicious-based webinterface, and a bunch of perl scripts which would build and execute ffmpeg command lines using string interpolation. As a quick hack that I needed to get working while writing it in my spare time in half a year, that approach was workable and resulted in successful postprocessing after FOSDEM 2017, and a significant improvement in time from the previous years. However, I did not end development with that, and since then I've replaced the string interpolation by an object oriented API for generating ffmpeg command lines, as well as modularized the webinterface. Additionally, I've had help reworking the user interface into a system that is somewhat easier to use than my original interface, and have slowly but surely added more features to the system so as to make it more flexible, as well as support more types of environments for the system to run in.

One of the major issues that still remains with SReview is that the administrator's interface is pretty terrible. I had been planning on revamping that for 2020, but then massive amounts of people got sick, travel was banned, and both the conferences that I work on were converted to an online-only conference. These have some very specific requirements; e.g., both conferences allowed people to upload a prerecorded version of their talk, rather than doing the talk live; since preprocessing a video is, technically, very similar to postprocessing it, I adapted SReview to allow people to upload a video file that it would then validate (in terms of length, codec, and apparent resolution). This seems like easy to do, but I decided to implement this functionality so that it would also allow future use for in-person conferences, where occasionally a speaker requests that modifications would be made to the video file in a way that SReview is unable to do. This made it marginally more involved, but at least will mean that a feature which I had planned to implement some years down the line is now already implemented. The new feature works quite well, and I'm happy I've implemented it in the way that I have.

In order for the "upload" processing and the "post-event" processing to not be confused, however, I decided to import the conference schedules twice: once as the conference itself, and once as a shadow version of that conference for the prerecordings. That way, I could track the progress through the system of the prerecording completely separately from the progress of the postprocessing of the video (which adds opening/closing credits, and transcodes to multiple variants of the same video). Schedule parsing was something that had not been implemented in a generic way yet, however; since that made doubling the schedule in that way rather complex, I decided to bite the bullet and (finally) implement schedule parsing in a generic way. Currently, schedule parsers exist for two formats (Pentabarf XML and the Wafer variant of that same format which is almost, but not quite, entirely the same). The API for that is quite flexible, and I'm happy with the way things have been implemented there. I've also implemented a set of "virtual" parsers, which allow mangling the schedule in various ways (by either filtering out talks that we don't want, or by generating the shadow version of the schedule that I talked about earlier).

While the SReview settings have reasonable defaults, occasionally the output of SReview is not entirely acceptable, due to more complicated matters that then result in encoding artifacts. As a result, the DebConf video team has been doing a final review step, completely outside of SReview, to ensure that such encoding artifacts don't exist. That seemed suboptimal, so recently I've been working on integrating that into SReview as well. First tests have been run, and seem to be acceptable, but there's still a few loose ends to be finalized.

As part of this, I've also reworked the way comments could be entered into the system. Previously the presence of a comment would signal that the video has some problems that an administrator needed to look at. Unfortunately, that was causing some confusion, with some people even thinking it's a good place to enter a "thank you for your work" style of comment... which it obviously isn't. Turning it into a "comment log" system instead fixes that, and also allows for better two-way communication between administrators and reviewers. Hopefully that'll improve things in that area as well.

Finally, the audio normalization in SReview -- for which I've long used bs1770gain -- is having problems. First of all, bs1770gain will sometimes alter the timing of the video or audio file that it's passed, which is very problematic if I want to process it further. There is an ffmpeg loudnorm filter which implements the same algorithm, so that should make things easier to use. Secondly, the author of bs1770gain is a strange character that I'd rather not be involved with. Before I knew about the loudnorm filter I didn't really have a choice, but now I can just rip bs1770gain out and replace it by the loudnorm filter. That will fix various other bugs in SReview, too, because SReview relies on behaviour that isn't actually there (but which I didn't know at the time when I wrote it).

All in all, the past year-and-a-bit has seen a lot of development for SReview, with multiple features being added and a number of long-standing problems being fixed.

Now if only the pandemic would subside, allowing the whole "let's do everything online only" wave to cool down a bit, so that I can finally make time to implement the admin interface...