Is this object discrete or continuous?

tywen kelly
8 min readMar 17, 2021
“Tensegrity Between The Discrete And The Continuous” (2021)

Tweening is a technique in animation where an animator adds intermediate frames in between two key frames. An example is an animation of a character walking. In the first keyframe the character might have their left foot forward. In the second, their right foot. The tween frames are the frames added that smooth out the motion of the character walking so that their legs appear to move forward and back. As you can imagine, the act of tweening is an art, and all animators have their own flavor of going about it.

Funny enough, tweening has a few parallels to digital video compression today. Most of the videos hosted online are compressed using the H264 protocol (or some variant like H265, VP8, or VP9). The efficiency of compressed video is really amazing. A minute long video can be the same file size as a single large still image. It achieves this by only storying a few keyframes from the video, instead of storing each frame as an individual image. It uses those keyframes as reference points. Each subsequent frame of video is then stored as “delta” information (or more technically “P frames” and “B frames”), which points to a change from a parent key frame. This way, if parts of the tween frames are at all the exact same as their reference keyframe, the video compression only needs to store a little of data that says “this pixel stays the same spot is the the same color for key frame 1 and tween frame 1” rather than store the data for an entirely new pixel.

Areas of a compressed digital video that change are tracked using motion vectors, represented by the white arrows. Video compression saves space because the video only stores that chunk of color once and tracks how it moves over time, rather than duplicating that chunk of color every frame. Areas of the image that don’t change at all save even more space, because they don’t have any time data. In this example, there are a few frames that have no arrows at all. Those frames are the key frames, which the other frames reference. These motion vectors are a kind of tweening.

The fact that tweening has persisted from the animation days to the digital century tells me that it rides a deeper culture undercurrent. It speaks to tweening as a possible meta-technique to make something feel magical. A classic Disney animation feels magical on the same plane that a digital video feels magical. Maybe both animation and video compression are magical because they both hold the tension of existing as discrete frames but also contain the capability to appear continuous? How can something composed of solid, demarcated bits of information appear organic, round, and in flux?

I wanted to explore the tension of the magical tween space between discrete and continuous. At the outset I knew intuitively that this tension could only be explored by working in between particles and bits. Particles and bits bracket the spectrum of this whole space. Particles are themselves a concurrent constitution of a wave and particle, whose only constant is change. They are of an atomic world and messily embody what it means to be continuous in the sense they are in perpetual motion and have a relentless aversion to being pinned down. On the other hand, bits are the symbolic form of an inert state, representing a thing of known or intended position, orientation, and velocity. Bits are usually binary, but if they aren’t, they must hold some whole tautological truth — a bit is because it cannot be reduced into smaller bits or explained as an effect of something else.

Could an object wedge itself in a space of cognitive dissonance? If it did, it needed to hold competing truths or the discrete and the continuous, of particles and bits, simultaneously. In other words it needed to be both a tween and a keyframe. Perhaps then, crushed and stretched by the tensegrity of those opposing forces, could an object have enough support serve as a fulcrum to inspire more thinking on the topic.

“Lets make that object,” I thought. So, I thought it proper to begin to explore the space using the medium of video, as that was where my amorphous thought train had originated. To keep things simple, I looked back to the first example of a motion film. I found the series Animal Locomotion, which was was (arguably) the first ever “movie”, captured as a sequence of still images by Edward Muybridge in the late 1800’s. This series of images captured the silhouettes of animals and people in motion. At the time designed to prove if a horse lifted all its hooves off the ground when galloping, the series now serves me as a pristine and authentic dataset of the idyllic period of quantification-photography which sought to capture the earnest truth of an event.

The series enclosed the essence what it meant to translate a continuous thing into discrete chunks, in an unadulterated channeling of The Enlightenment, that selectively siloed individual frames as a kind of scientific sampling. These days, in the contemporary format of digital video it is more difficult to disentangle the increasing quantity of factors behind an image. Image production has become so entwined with technological, historical, and social stories that it seemed too rich a thing digest. Choosing Muybridge’s series over a digital stream was a choice to streamline the richness of the sample data.

Plus, perhaps by bringing the clarity of the series into the Age of Entanglement today, the old content of Animal Locomotion can be re-examined for what it was: an active practice of The Enlightenment’s scientific values.

A running goat from the Animal Locomotion series.

I went online and downloaded high quality TIFF versions of the image sequences, originally printed as collotypes, from The Library of Congress. The images were presented as a grid, each cell a “key frame” of a continuous motion exempt from interpolation. As individual images they held no capacity of motion, no magic. They were deathly inert, static, discrete, caged in with the border of their frames.

I chopped up the grid and exported the images as still frames, and brought them into my video editing software, where I laid each out in sequence as a video frame. The frames played back choppily, at 12 frames a second. Still no magic. The motion was not smooth — I could see each frame as a frame. I had a low-level desire to smooth out the motion. I imagine it is the same desire that derives from wanting brush back an errant fluff hair sticking out of your head, untuck an uneven sleeve of you shirt, or smooth down the grain of some wood with sand paper.

I could have run the choppy video through software to interpolate and smooth out the sequence. But I knew that process would not explain anything new to me. I needed to see it in a new medium, to recontextualize it back into the area of the discrete-continuous tension. The natural choice at this point was to work with it in three dimensions as a sculpture.

I began the arduous task of converting the image sequence into a format which could become physical. First I stripped the image of pixels by converting it into vectorized curves. Then from the vectors I began to extrude in 3D and generate more curves to connect each vectorized image along the Z-axis, thus forcing each image to be a layer in a taller sculptural volume.

When I saw the effect of lofting a brand new mesh between the layers of each frame, I became excited. It seemed to be able to hold in the qualities of being a discrete thing, but also be able to emit out a continuous flow. It seemed to perform the tensegrity I was looking for.

Thus far the entire process of cutting up the grid, converting to vector, pulling the vectors into a layered mesh, had been done with software. To fully close the loop between particles and bits, I felt compelled to bring this virtual item from bits back into atomic particles. What hypocrisy to not bring a thing of bits into particles when the whole point of the piece was to speak to that dichotomy in the first place!

At the time I did not have a way to “particle-ize” this, but I quickly ordered a 3D printer, and (after a few months of backorder waiting) it arrived and I was ready to print. The first prints I did were on a black plastic, which were cool, but it somehow had lost some of the magic I experienced on the screen. I got to thinking it had to do with the satin material of PLA, which dispersed light in an uninspiring manner. So I experimented with the colors and ordered paint designed for painting miniature Lord of the Ring figurines. That didn’t work out. Applied, it somehow looked cheaper. I meandered my way to asking for input from friends and other artists, and we honed in the idea of a mirror finish. I experimented with applying the mirror finish over the course of weeks, trying different methods of application, layering, and drying times. Finally I was happy when the resulting sculpture bounced some of that magic I had felt earlier on the screen and even earlier in studying animation and video compression back into me. I could see slivers of reflections in it, as the 3D video seemed to glimmer, bend, and refract waves of light, but also it having a weight, and be a movie I could hold in my hands — something I hadn’t experienced since the VCR and DVD days.

When I reflect on the piece now I do think I can allow myself to put some weight on it. I’m not too worried it will break under the load of cognitive dissonance it holds. It is both a tween and a keyframe, a subject and an object, a particle and a bit. So, to answer the question in the subtitle: “is this object discrete or continuous?” Right this moment, I’d say it’s neither. This tension does not for me entrench the poles of the dichotomy but provide nourishment for something larger, emergent, more gaseous. It’s something else entirely. Heidegger called this thing “experience”, so I’ll go with that: this object is experience.

While this experiment has given me an inkling of clarity on this thing of “experience”, it has also came upon an unexpectedly impossible-to-answer question: is the universe fundamentally discrete or continuous? It turns out that this is a question physicist and philosophers before them have been quarrelling about for decades. If I broke down space would I get small chunks of matter, or would I be left with a wriggly pile of waves? If I broke down time would I get a neat arrangement of small divisible moments, or would I be left with some weird iridescent liquid that slithers through time? This was not something I was expecting to find. Nevertheless I am happy to led me here. In general I’m satisfied with the result. But having this looming question inspires me to keep going — this is just the fulcrum after all. The next step should to make this experience human scale, bigger! Something that I could look in the face. We’ll see what kind of unexpected questions come of that.

“Tensegrity Between The Discrete And The Continuous” (2021)