Video Briefing

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Written by Geep, 2020

This extends the tutorial on Briefing and serves as a useful bridge to the format specifications given in Cutscene video with FFmpeg.


Introduction

Style and Content

Like other TDM briefing styles, a video conveys important information or teasers at the game start. After first viewing, the player can subsequently skip it.

A typical "historical documentary" approach to producing a video briefing would be to:

  • capture screen shots from within the game
  • supplement these with other images
  • assemble the results into a timeline and add pans, zooms, rotations, transitions, titles, overlays, and special effects
  • possibly include video clips, e.g., video capture during game play; animated logos
  • separately develop a soundtrack using standard TDM sound clips and other music, sound effects, and custom narration (with possibly multiple voices). The heart of the briefing is conveyed by the narrator.
  • be cognizant of copyright and licensing issues

Specific software systems to do all this - video capture & editing, audio recording & editing, animation, and FX - are beyond our scope here. Also touched on elsewhere are other methods that could convey briefing-like information during the game, not at the beginning:

  • Playing ROQ Video Files demonstrates in-game video on a small screen. The example uses an in-game laptop model, but is applicable to more "lore friendly" surfaces like magic mirrors.
  • Full-Screen Video Cutscenes uses methodology similar to but different in detail from what is described here.

Video and Audio Formats

Traditionally, games using the id engine have used the RoQ format for video, with separate .OGG audio. RoQ remains supported in TDM for compatibility with existing FMs. But starting in TDM 2.06, a focused set of more popular formats is preferable with new FMs. The new formats allow a higher quality presentation. The audio source may be either a separate file, or from the video itself.

Quick Start

The quickest way to implement this in your FM is to copy a video briefing from an existing recent FM, then replace the AV media files with your own. We will use as our example Goldwell's "Shadows of Northdale ACT II" from 2019. This has a single-mission briefing and uses a .MP4 video with a separate .OGG soundtrack. After you have installed it, look within northdale2.pk4 for these files:

  • guis/mainmenu_background.gui
  • guis/mainmenu_briefing_video.gui
  • guis/mainmenu_custom_defs.gui
  • materials/briefing.mtr
  • video/briefing.mp4
  • sound/video/briefing_video.ogg

Copy these to your own FM, creating folders as needed. When you compile and run your FM, you should see and hear the video briefing (with its quite high production values) instead of a text briefing page.

If you want to change media filenames, or make certain other customizations, mainmenu_custom_defs.gui is where to start. It has documentation on additional configurations, like multiple briefings for multi-mission campaigns, or adding mission debriefing videos, that are not covered here.

Skipping a Video Briefing

The video briefing, once started, can be skipped by either:

  • Pressing LMB. This is the best way, though the viewer may not always be aware of it.
  • Using the ESC key. This aborts to the text Briefing page, from which the viewer may navigate to the Objectives page. It is not possible to resume the video briefing.

Regarding the latter, note that Goldwell's method includes a special treatment so that when a briefing video ends normally (not skipped), the viewer arrives directly at the Objectives page, not the Briefing page. Unfortunately, that is not the case with ESC skipping. You might accommodate this by editing the xdata/briefing.xd to have either:

  • No text
  • Something like: "Select 'Objectives' to continue..."
  • A text summary or transcript of the video briefing.

More About Formats

When getting set to replace the media assets with your own, you may find it informative to inspect the properties of northdale2's briefing.mp4 and briefing_video.ogg files, e.g.:

  • Video has 1920 wide x 1080 high frames, at 29.97 frames per second.
  • Audio is stereo, 128kps bit rate, 48.000 kHz sampling.

There are other media options (e.g., .AVI), but in any event be sure to be compliant with format restrictions given in Cutscene video with FFmpeg. There you will also find details of how to use a video's audio instead of a separate audio file. For still more, see 2.06 - Videos Without RoQ

If you do need to work with the RoQ format, you can find similar examples among your installed FMs (i.e., by searching for *.roq files). There is a pioneering (circa 2006, but revised in 2020) TDM report on Playing ROQ Video Files. This covers RoQ creation with 2006-era and 2015-era tools, the latter from the useful information at RoQ - particularly ZaRR's RoQ How-to for OpenArena Mappers. Note that RoQ file duration is limited to 1 minute. (Possibly the mainmenu_... guis can be used to sequence multiple RoQ files.)

See also: Overview of GUI scripting and idDevNet GUIs

Debugging Playback

If your video shows a black screen, you may have a GUI error. In the console, "testgui guis/xxxx.gui" (note the partial path inclusion) may be helpful to locate where.