Clip02, click thumbnails for full size frames.

00:06 min:sec
00:18 min:sec
00:30 min:sec
00:42 min:sec
00:54 min:sec
What do I see and hear?

I see the same shapes as in clip 01. Predictable as all 10 clips are from the same improv session, using the same input.

Horizontal bars, appearing wider than the previous clip, run slowly through the frame [1]. These wider bars are mostly purple or blue. Behind the wide bars are the shapes, red and green, and narrower bars or stripes. Some of the narrow bars seem brighter than others, These brighter, or lighter bars, are orange, yellow and white. As well, the whole frame appears to be pulsating.

I also notice that the shapes are sometimes white on black, sometime black on white or inverted. About 20 sec into the clip the shapes become contoured, breaking into alternating bands of light and dark [2]. The light areas take on the color of the bars. At 30 sec the contouring disappears, then reappears, around 40 sec. The clip moves slowly, wide bands running slowly through the frame. The sound to this point has been a low, continuous drone.

Then, halfway through the clip, I hear a series of higher pitched tones and a number of narrower bars fill the frame. As the higher tones drop, the bars widen. The colors are now mostly purples and green over a black and white background, they appear luminescent. The higher tones and narrow bars fade, the low tone and wide bars return. At 1 min 30 sec into the clip the contour lines return, moving through the shapes. The shapes become pixellated [3], then contoured, then cycle from contoured to pixellated. This continues until the clip ends.

[1] The relationship between lower pitched tones and wide bars, and high pitched sounds and narrow bars results from the relationship between the pitch and vertical sync. Video sync mixes vertical sync and horizontal sync. Vertical sync determines the start of each field, two fields make up a frame. Horizontal sync determines the start of a new line. Assume vertical sync runs at 60 Hz, or 60 cycle per sec. At that rate a 60 cycle tone produces a single, horizontal bar in the frame, a 120 cycle tone produces two bars, a 180 cycle tone produces three bars, and so on.

What makes the bars appear to move from up or down in the frame? Let’s raise the pitch of the tone to 70 cycles per sec. The vertical sync remains the same, 60 cycles per second, a 10 cycle difference. Starting with a single frame, assume the bar is sitting mid-frame, halfway between the bottom and top of the frame. The bar is centered on the the peak or top of the waveform. There’s a field every 1/60th of a second and a new peak every 1/70th of a second. The bar will appear to be moving up, from bottom to top of the frame.

And this is only part of the story, more later.

[2] Contouring is produced by the “bit swapping” on the Jone’s MVIP.

[3] Pixelation is one of the “modes” on the Jone’s MVIP.

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