How the surveillance footage was made

There are four surveillance clips in Chapter One. Each one is a real video file rendered on the server, not a slideshow with a filter on it, and each one is built from the times written in its own published scene description.

Stepped frames are correct

The clips do not move smoothly. Each camera plate holds, then the picture changes to the next plate in one step.

That is not a shortcut, it is the period. A 1986 multiplexed CCTV recorder shared one videotape between eight or sixteen cameras by giving each of them a slice of the recording head's time. Played back, an individual camera's footage advances in visible steps, and a person walking through frame appears as a series of positions rather than a walk. The clips in this game step because the recorder they are supposed to have come off stepped.

The timecode is real

The burned-in timecode is generated from the clip's start time and advances one second per second of playback. It is drawn after everything else, so it keeps running over a black frame — which matters for two of the four clips, because in one of them the picture is covered and in another it has not come back yet.

CAM-02 ends with the lens covered. The last two seconds of that clip are cloth, and then the picture goes, and the timecode carries on over black exactly as a real recorder's would.

What is over the top

Applied in this order, to every clip:

• A slight defocus, because a tube camera never quite resolves.
• Scanlines, alternate lines darkened.
• Per-frame grain, different every frame.
• A head-switching band along the bottom seven lines, the noise stripe a worn tape leaves where the drum picks up.
• Timed dropouts — a few lines going white and then black for two frames, at fixed points in each clip.
• A vignette, because these lenses fall off hard at the corners.

Every clip ships a scene description

The same rule as the audio. Every clip has a full written description of what happens in it, with times, on the same page as the video. Nothing in this game is only visible if you can see moving pictures.

CAM-08 also ships the comparison still its description refers to: the same ward from the same camera at 21:44 the previous evening, with all twelve beds stripped and the mattresses stacked against the left wall. You are meant to be able to hold those two frames next to each other, so both of them are in the archive.

One thing we had to build

The system's own video encoder turned out to be a deliberate stub — a library that satisfies the link and then reports "unable to create encoder" when you ask it to do anything. A real H.264 encoder was built from source and installed alongside it rather than over it, and the build script selects it explicitly. Nothing packaged was replaced, so removing that one directory puts the machine back exactly as it was.