Media Creation Guide

Pre-recorded Talk

Pre-recorded talks serve to minimize the impact of potential speaker-side technical problems and ensure minimal time overruns. Each paper is alotted 20 minutes in its session, so to enable at least 5 minutes of discussion, your talk must not exceed 15 minutes. The slides should use a 16:9 aspect ratio, and must include a title slide that has at least the title of your paper and a list of authors and affiliations in it. We prepared a PowerPoint template that fulfills all requirements.

Production tips: Make sure to start your video by introducing yourself with your name, affiliation, and the title of your presentation, as you normally would when giving a talk at a conference. It is not mandatory, but you are strongly encouraged to include a small camera view of you recording the talk in a suitable corner of your presentation. Being able to see the speaker greatly increases audience engagement. Even a very small view helps, so having to move some slide contents out of the way here and there to make space will be worth it.

Your talking will be most understandable if you record using a headset (or if you have access to one, a proper [desktop] microphone). Aim for a uniform volume in the audio track and avoid distorted or noisy audio. As an advanced technique, employing an audio compressor/limiter in your recording software (available e.g. in OBS Studio) can help keep your talking volume constant at the desired level.

If you don’t yet have a preferred toolchain for recording talks set up, we strongly recommend using OBS Studio (https://obsproject.com/). It enables you to easily record your screen and yourself at the same time, while also offering many advanced options, especially with regards to encoding and output formats. You will be able to produce a fully compliant video file using only OBS. For an example of a basic OBS Studio setup that will work well for VMV 2021, we recommand this excerpt from the IEEE VIS recording guide [1].

Finally, after recording your talk, please rewatch it to ensure that video and audio were recorded correctly.

Technical specifications

Duration: 15 minutes maximum
Resolution: 16:9 aspect ratio, HD 1080p
Framerate: 30 fps preferred (will otherwise be resampled on-the-fly when streaming)
Video Codec: H.264 / MPEG4-AVC
Audio Codec: AAC (preferred) or MP3
Container: mp4 or mkv
file size: please try to stay below 512 MB

Spotlight Video

The 50 seconds spotlight video serves two purposes: it will be shown in a virtual fast-forward session on Zoom, and it will be made available as part of a fast-forward playlist on Youtube. The video should advertise your work in a way that motivates viewers to attend your session and join the discussion. It may do so in a humourous way, but it should still give the viewer a clear idea what to expect. If you include background music (which we generally discourage), it should be copyright-free or you must certify that you are licensed to use it. The spotlight video will stay online (in the Youtube playlist) for some time after the conference.

You should not include any title, author or day/session information at the beginning of the spotlight video ‒ this information will be added by us by prepending a standardized title card to your video.

Production tips: while any style of video is welcome, it is generally a good idea to narrate over a collage of your work in action or a slideshow of key visual elements (result images, figures) from your paper to make it recognizable. Try to show more than tell. Use simplified graphics to explain the basic ideas. Don’t use too much text and focus the essential information on the central area of the canvas. There will be day/session information overlays at the very bottom of the video, so don’t place anything important there.
Voice-over narration is strongly recommended to make the video most useful, but is not mandatory. Ideally, the video also catches the viewer’s attention if the audio is muted (prompting them to unmute ;)). Be creative and have fun with it!

If you don’t have experience in video production, then one way of creating the spotlight video is to compose your visuals in slides (PowerPoint, Keynote, …) and capture your screen. You can again do that using OBS Studio, but most presentation software also provides video export functionality, which might or might not be easier than using OBS, depending on what you are aiming to do.

Powerpoint can export .mp4 videos. You can add videos to slides and set the timings in the animation menu. Some instructions can be found here: https://support.microsoft.com/en-us/office/turn-yourpresentation-into-a-video-c140551f-cb37-4818-b5d4-3e30815c3e83
Similarly, you can also export videos from Apple Keynote: https://support.apple.com/guide/keynote/record-presentations-tan81813d552/mac

Technical specifications

Duration: 50 seconds (a couple of frames more or less is ok)
Resolution: 16:9 aspect ratio, HD 1080p
Framerate: 30 fps preferred (will otherwise be resampled by Youtube and on-the-fly when streaming)
Video Codec: H.264 / MPEG4-AVC
Audio Codec: AAC (preferred) or MP3
Container: mp4 or mkv
max. file size: please try to stay below 256 MB

Encoding Hints

For reasonably good quality, we suggest using a combined bitrate of 1.5 Mbit/s or higher for your talk, and 20 Mbit/s or higher for your spotlight video (since the latter could contain a lot of motion). If you have advanced video settings available, single-pass encoding with a constant rate factor (CRF) of 19 should result in reasonable bitrates in most cases. If you are unsatisfied with your resulting video quality, try higher bitrate settings (e.g. by lowering the CRF in your encoder settings).

If your recorded videos are not in the required format(s), you can use ffmpeg (https://ffmpeg.org/) or the Handbrake GUI (https://handbrake.fr/) for conversion.

Using ffmpeg, the following command converts to a compatible format:
ffmpeg -i your_talk_recording.ext -c:a aac -b:a 128k -c:v libx264 -crf 19 -vf "scale='min(1920,iw)':'min(1080,ih)'" -movflags +faststart -preset slow talk.mp4

References

[1] IEEE VIS 2020 information material for presenters, http://ieeevis.org/year/2020/info/presenter-information/talk-recording-guide