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...Or did the metaverse just turn a shade more uncannily creepy?

Mesh to MetaHuman lets creators import a facial mesh to create a photorealistic 3D character.

Creating your virtual clone isn’t as difficult as you’d think.

Epic Games recently introduced Mesh to MetaHuman, a framework for creating photorealistic human characters. It lets creators sculpt an imported mesh to create a convincing character in less than an hour.

“It’s incredibly simple compared to a lot of other tools,” says Stu Richards (a.k.a. Meta Mike), partner success lead at GigLabs and Cofounder of Versed. “I’d compare it to a character creator in a game.”

Photorealistic characters remain the holy grail of 3D graphics. It’s a difficult task due to the “uncanny valley” phenomenon, which theorizes humanlike characters become less appealing as they approach a realistic representation. Characters in big-budget games or animated films take months (if not years) of effort and often rely on detailed scans of real human models captured with expensive, specialized equipment.

Mesh to MetaHuman breaks this barrier to entry. Richards used his iPhone to scan a model of his face and create his own MetaHuman avatar. “After, I think, about 40 photos, it put together all the different angles, and creates a 3D model of my face,” he says. “You take that mesh, bring it into Unreal Engine…and overlay a MetaHuman head onto that mesh.”

“The barrier of entry to getting into the tool itself is almost zero.” —Justin Vu, 3D animator

The mesh begins as an untextured, gray surface, but MetaHuman’s interface provides numerous options that can be changed with a click. Creators can tweak physique, head and facial hair, eyebrows, skin tone, and even the look of pores and opacity of skin to create a convincing virtual clone—or model an idealized avatar.

MetaHuman also rigs the mesh for animation. “You can select different poses and different animations,” says Richards. “But when you bring that back into Unreal, you have a lot of flexibility. You can create your own animation sets, create full-on controller mapping.”

Creators can even use Live Link, an Unreal Engine plug-in, to capture facial expressions in real time on a smartphone or tablet and stream it to a MetaHuman character.

Live Link Face Tutorial with New Metahumans in Unreal Engine 4www.youtube.com

While Mesh to MetaHuman is more approachable than previous workflows, Richards cautions that some familiarity with 3D modeling and animation is required for the best results. Creators can expect minor errors in the mesh captured by a smartphone or tablet that must be fixed in 3D-modeling software. And while MetaHuman’s interface is simple, Unreal Engine 5 remains complex.

“From a user perspective, I think that at this point in time, having something a bit more lightweight, with lower fidelity, and more interoperable, is what’s going to resonate with people,” says Richards. “Especially in the NFT and web3 world.”

Contrary to its name, MetaHuman is not a tool exclusively for metaverse avatars. In fact, that’s not even its primary use case (for now). Rather, MetaHuman is, according to Epic Games, ideal for creators working on smaller projects with a modest budget, such as independent games and short films.

Justin Vu, an animator and 3D generalist specializing in filmmaking with Maya and Unreal Editor, is one such creator. He put MetaHuman to work in a series of promotional shorts from Allstate Insurance Company called The Future of Protection. Vu was able to use MetaHuman despite having little prior experience with Unreal Engine.

“The barrier of entry to getting into the tool itself is almost zero,” says Vu. “So long as you have a computer that runs a modern video game, you can get started.”

It was especially useful during the peak of COVID. The difficulty of shooting live action in the middle of a lockdown and travel restrictions made animation appealing. MetaHuman helped Vu create convincing animated characters in a fraction of the time that might otherwise be required.

“What’s great about Metahuman is that it generates high fidelity models, which can be used with facial recording capture,” says Vu. “It’s very convincing to the average person and does a lot to cross the uncanny valley.”

MetaHuman characters can be imported to Unreal Engine projects, such as the Matrix Awakens demo. Epic Games

Animators can conduct a virtual casting by quickly iterating on characters that differ in age, hairstyle, height, facial structure, and physique. The tool’s automatic animation rigging is especially useful, as Vu says manual rigging of a high-fidelity 3D character can take “a few weeks, if not a few months.” Quick rigging helps animators try poses and expressions before deciding which character to use for a project.

Despite these strengths, Vu shared Richards’s caution that MetaHuman’s approachability has limits. While creating a character is relatively simple, character models and animations require tweaks for best results. He also notes MetaHuman has a limited selection of wardrobe options. This can be changed once a character is imported to Unreal Engine but, again, requires expertise in traditional 3D modeling and animation.

“While the tools are accessible and easy to start up, it really requires the hand of a good animator, a good actor, or good director, to drag it out of uncanny valley and make it convincing,” says Vu.

This sets the stage for competition in the space as alternative tools become more capable. Unity purchased Ziva Dynamics, a VFX studio known for its work creating lifelike characters, in January 2022. Other alternatives, like Animaze and Ready Player Me, lack realism but don’t require experience with 3D modeling or animation for usable results. These tools are popular with Vtubers and fans of metaverse social platforms like VRChat.

MetaHuman leads the effort to cross the uncanny valley—but it’s still anyone’s race.

Correction (18 July 2022): This story was updated to remove reference to a short film Justin Vu worked on, in which he used Unreal Engine but did not use MetaHuman as was originally reported.

Matthew S. Smith is a freelance consumer-tech journalist. An avid gamer, he is a former staff editor at Digital Trends and is particularly fond of wearables, e-bikes, all things smartphone, and CES, which he has attended every year since 2009.

Open Circuits showcases the surprising complexity of passive components

Eric Schlaepfer was trying to fix a broken piece of test equipment when he came across the cause of the problem—a troubled tantalum capacitor. The component had somehow shorted out, and he wanted to know why. So he polished it down for a look inside. He never found the source of the short, but he and his collaborator, Windell H. Oskay, discovered something even better: a breathtaking hidden world inside electronics. What followed were hours and hours of polishing, cleaning, and photography that resulted in Open Circuits: The Inner Beauty of Electronic Components (No Starch Press, 2022), an excerpt of which follows. As the authors write, everything about these components is deliberately designed to meet specific technical needs, but that design leads to “accidental beauty: the emergent aesthetics of things you were never expected to see.” From a book that spans the wide world of electronics, what we at IEEE Spectrumfound surprisingly compelling were the insides of things we don’t spend much time thinking about, passive components. Transistors, LEDs, and other semiconductors may be where the action is, but the simple physics of resistors, capacitors, and inductors have their own sort of splendor. High-Stability Film Resistor All photos by Eric Schlaepfer & Windell H. Oskay This high-stability film resistor, about 4 millimeters in diameter, is made in much the same way as its inexpensive carbon-film cousin, but with exacting precision. A ceramic rod is coated with a fine layer of resistive film (thin metal, metal oxide, or carbon) and then a perfectly uniform helical groove is machined into the film. Instead of coating the resistor with an epoxy, it’s hermetically sealed in a lustrous little glass envelope. This makes the resistor more robust, ideal for specialized cases such as precision reference instrumentation, where long-term stability of the resistor is critical. The glass envelope provides better isolation against moisture and other environmental changes than standard coatings like epoxy. 15-Turn Trimmer Potentiometer It takes 15 rotations of an adjustment screw to move a 15-turn trimmer potentiometer from one end of its resistive range to the other. Circuits that need to be adjusted with fine resolution control use this type of trimmer pot instead of the single-turn variety. The resistive element in this trimmer is a strip of cermet—a composite of ceramic and metal—silk-screened on a white ceramic substrate. Screen-printed metal links each end of the strip to the connecting wires. It’s a flattened, linear version of the horseshoe-shaped resistive element in single-turn trimmers. Turning the adjustment screw moves a plastic slider along a track. The wiper is a spring finger, a spring-loaded metal contact, attached to the slider. It makes contact between a metal strip and the selected point on the strip of resistive film. Ceramic Disc Capacitor Capacitors are fundamental electronic components that store energy in the form of static electricity. They’re used in countless ways, including for bulk energy storage, to smooth out electronic signals, and as computer memory cells. The simplest capacitor consists of two parallel metal plates with a gap between them, but capacitors can take many forms so long as there are two conductive surfaces, called electrodes, separated by an insulator. A ceramic disc capacitor is a low-cost capacitor that is frequently found in appliances and toys. Its insulator is a ceramic disc, and its two parallel plates are extremely thin metal coatings that are evaporated or sputtered onto the disc’s outer surfaces. Connecting wires are attached using solder, and the whole assembly is dipped into a porous coating material that dries hard and protects the capacitor from damage. Film Capacitor Film capacitors are frequently found in high-quality audio equipment, such as headphone amplifiers, record players, graphic equalizers, and radio tuners. Their key feature is that the dielectric material is a plastic film, such as polyester or polypropylene. The metal electrodes of this film capacitor are vacuum-deposited on the surfaces of long strips of plastic film. After the leads are attached, the films are rolled up and dipped into an epoxy that binds the assembly together. Then the completed assembly is dipped in a tough outer coating and marked with its value. Other types of film capacitors are made by stacking flat layers of metallized plastic film, rather than rolling up layers of film. Dipped Tantalum Capacitor At the core of this capacitor is a porous pellet of tantalum metal. The pellet is made from tantalum powder and sintered, or compressed at a high temperature, into a dense, spongelike solid. Just like a kitchen sponge, the resulting pellet has a high surface area per unit volume. The pellet is then anodized, creating an insulating oxide layer with an equally high surface area. This process packs a lot of capacitance into a compact device, using spongelike geometry rather than the stacked or rolled layers that most other capacitors use. The device’s positive terminal, or anode, is connected directly to the tantalum metal. The negative terminal, or cathode, is formed by a thin layer of conductive manganese dioxide coating the pellet. Axial Inductor Inductors are fundamental electronic components that store energy in the form of a magnetic field. They’re used, for example, in some types of power supplies to convert between voltages by alternately storing and releasing energy. This energy-efficient design helps maximize the battery life of cellphones and other portable electronics. Inductors typically consist of a coil of insulated wire wrapped around a core of magnetic material like iron or ferrite, a ceramic filled with iron oxide. Current flowing around the core produces a magnetic field that acts as a sort of flywheel for current, smoothing out changes in the current as it flows through the inductor. This axial inductor has a number of turns of varnished copper wire wrapped around a ferrite form and soldered to copper leads on its two ends. It has several layers of protection: a clear varnish over the windings, a light-green coating around the solder joints, and a striking green outer coating to protect the whole component and provide a surface for the colorful stripes that indicate its inductance value. Power Supply Transformer This transformer has multiple sets of windings and is used in a power supply to create multiple output AC voltages from a single AC input such as a wall outlet. The small wires nearer the center are “high impedance” turns of magnet wire. These windings carry a higher voltage but a lower current. They’re protected by several layers of tape, a copper-foil electrostatic shield, and more tape. The outer “low impedance” windings are made with thicker insulated wire and fewer turns. They handle a lower voltage but a higher current. All of the windings are wrapped around a black plastic bobbin. Two pieces of ferrite ceramic are bonded together to form the magnetic core at the heart of the transformer.

Eric Schlaepfer was trying to fix a broken piece of test equipment when he came across the cause of the problem—a troubled tantalum capacitor. The component had somehow shorted out, and he wanted to know why. So he polished it down for a look inside. He never found the source of the short, but he and his collaborator, Windell H. Oskay, discovered something even better: a breathtaking hidden world inside electronics. What followed were hours and hours of polishing, cleaning, and photography that resulted in Open Circuits: The Inner Beauty of Electronic Components (No Starch Press, 2022), an excerpt of which follows. As the authors write, everything about these components is deliberately designed to meet specific technical needs, but that design leads to “accidental beauty: the emergent aesthetics of things you were never expected to see.”

From a book that spans the wide world of electronics, what we at IEEE Spectrumfound surprisingly compelling were the insides of things we don’t spend much time thinking about, passive components. Transistors, LEDs, and other semiconductors may be where the action is, but the simple physics of resistors, capacitors, and inductors have their own sort of splendor.

All photos by Eric Schlaepfer & Windell H. Oskay

This high-stability film resistor, about 4 millimeters in diameter, is made in much the same way as its inexpensive carbon-film cousin, but with exacting precision. A ceramic rod is coated with a fine layer of resistive film (thin metal, metal oxide, or carbon) and then a perfectly uniform helical groove is machined into the film.

Instead of coating the resistor with an epoxy, it’s hermetically sealed in a lustrous little glass envelope. This makes the resistor more robust, ideal for specialized cases such as precision reference instrumentation, where long-term stability of the resistor is critical. The glass envelope provides better isolation against moisture and other environmental changes than standard coatings like epoxy.

It takes 15 rotations of an adjustment screw to move a 15-turn trimmer potentiometer from one end of its resistive range to the other. Circuits that need to be adjusted with fine resolution control use this type of trimmer pot instead of the single-turn variety.

The resistive element in this trimmer is a strip of cermet—a composite of ceramic and metal—silk-screened on a white ceramic substrate. Screen-printed metal links each end of the strip to the connecting wires. It’s a flattened, linear version of the horseshoe-shaped resistive element in single-turn trimmers.

Turning the adjustment screw moves a plastic slider along a track. The wiper is a spring finger, a spring-loaded metal contact, attached to the slider. It makes contact between a metal strip and the selected point on the strip of resistive film.

Capacitors are fundamental electronic components that store energy in the form of static electricity. They’re used in countless ways, including for bulk energy storage, to smooth out electronic signals, and as computer memory cells. The simplest capacitor consists of two parallel metal plates with a gap between them, but capacitors can take many forms so long as there are two conductive surfaces, called electrodes, separated by an insulator.

A ceramic disc capacitor is a low-cost capacitor that is frequently found in appliances and toys. Its insulator is a ceramic disc, and its two parallel plates are extremely thin metal coatings that are evaporated or sputtered onto the disc’s outer surfaces. Connecting wires are attached using solder, and the whole assembly is dipped into a porous coating material that dries hard and protects the capacitor from damage.

Film capacitors are frequently found in high-quality audio equipment, such as headphone amplifiers, record players, graphic equalizers, and radio tuners. Their key feature is that the dielectric material is a plastic film, such as polyester or polypropylene.

The metal electrodes of this film capacitor are vacuum-deposited on the surfaces of long strips of plastic film. After the leads are attached, the films are rolled up and dipped into an epoxy that binds the assembly together. Then the completed assembly is dipped in a tough outer coating and marked with its value.

Other types of film capacitors are made by stacking flat layers of metallized plastic film, rather than rolling up layers of film.

At the core of this capacitor is a porous pellet of tantalum metal. The pellet is made from tantalum powder and sintered, or compressed at a high temperature, into a dense, spongelike solid.

Just like a kitchen sponge, the resulting pellet has a high surface area per unit volume. The pellet is then anodized, creating an insulating oxide layer with an equally high surface area. This process packs a lot of capacitance into a compact device, using spongelike geometry rather than the stacked or rolled layers that most other capacitors use.

The device’s positive terminal, or anode, is connected directly to the tantalum metal. The negative terminal, or cathode, is formed by a thin layer of conductive manganese dioxide coating the pellet.

Inductors are fundamental electronic components that store energy in the form of a magnetic field. They’re used, for example, in some types of power supplies to convert between voltages by alternately storing and releasing energy. This energy-efficient design helps maximize the battery life of cellphones and other portable electronics.

Inductors typically consist of a coil of insulated wire wrapped around a core of magnetic material like iron or ferrite, a ceramic filled with iron oxide. Current flowing around the core produces a magnetic field that acts as a sort of flywheel for current, smoothing out changes in the current as it flows through the inductor.

This axial inductor has a number of turns of varnished copper wire wrapped around a ferrite form and soldered to copper leads on its two ends. It has several layers of protection: a clear varnish over the windings, a light-green coating around the solder joints, and a striking green outer coating to protect the whole component and provide a surface for the colorful stripes that indicate its inductance value.

This transformer has multiple sets of windings and is used in a power supply to create multiple output AC voltages from a single AC input such as a wall outlet.

The small wires nearer the center are “high impedance” turns of magnet wire. These windings carry a higher voltage but a lower current. They’re protected by several layers of tape, a copper-foil electrostatic shield, and more tape.

The outer “low impedance” windings are made with thicker insulated wire and fewer turns. They handle a lower voltage but a higher current.

All of the windings are wrapped around a black plastic bobbin. Two pieces of ferrite ceramic are bonded together to form the magnetic core at the heart of the transformer.

This article appears in the February 2023 print issue.