Seeing Eye To Eye:

Computer Vision Using WebAssembly

WASM I/O 2025

Ron Evans - @deadprogram

fed: @deadprogram@social.tinygo.org

bsky: @deadprogram.com

Ron Evans (@deadprogram)

Technologist For Hire

hybridgroup.com

Software that makes

your hardware work

Open Source Projects

tinygo.org

GoCV.io

computer vision using WebAssembly?

Industrial computer vision systems

Embedded Linux devices

Edge computing devices

Cloud computing

Agriculture

Transportation

Energy

Security

Manufacturing

Retail

A lot of computer vision applications have similar basic structure

lots of different parts to integrate

hard to run on different kinds of machines

hard to update

some need for customization

wasmvision.com

Get going with computer vision using WebAssembly

Capture video

Process it

Save or stream it

'wasmvision' command line interface

wasmVision engine

wasmVision processors

engine Written in Go

OpenCV

FFmpeg

GStreamer

GoCV

Wazero

All combined into a Single, statically linked binary*

*on Linux without GPU

wasmvision architecture

wasmvision Processors

Can be written using Go (TinyGo)

Rust

C

wasmCV

wasmcv.org

wasm interfaces for computer vision

defined Using wit (wasm interface type)

wit is part of the wasm component model

HOWEVER

wasmvision is not using the wasm component model

using wit to generate client interface wrappers and documentation

wypes

github.com/orsinium-labs/wypes

How Computer Vision Works

Mat

RGB Mat

How OpenCV/GoCV Works

How wit Works

interfaces

basic types

record

resource

world.wit file

See the code

Everything is generated from the .wit files

wasmCV Docs

See the code

wasmVision processors - go

`package wasmcv`

wit-bindgen-go

go.bytecodealliance.org


tinygo build -o blur.wasm -target=wasm-unknown --no-debug ./blur

Blur processor (Go)

See the code

Run Blur processor (Go)

wasmVision processors - rust

`crate wasmcv`

wit-bindgen

github.com/bytecodealliance/wit-bindgen


cargo build --target wasm32-unknown-unknown --release

Blur processor (Rust)

See the code

Run Blur processor (Rust)

wasmVision processors - c

`#include "wasmcv/imports.h"`

wit-bindgen

github.com/bytecodealliance/wit-bindgen


/opt/wasi-sdk/bin/clang --target=wasm32-unknown-unknown -O3 \
        --sysroot="${WASI_LIBC_SYSROOT}/lib/wasi-libc/sysroot" \
        -z stack-size=4096 -Wl,--initial-memory=65536 \
        -I$WASMCV_C_COMPONENTS_PATH -I$WASMVISION_C_COMPONENTS_PATH \
        -o ../blurc.wasm process.c \
        $WASMCV_C_COMPONENTS_PATH/wasmcv/imports.c $WASMCV_C_COMPONENTS_PATH/wasmcv/imports_component_type.o \
        $WASMVISION_C_COMPONENTS_PATH/wasmvision/platform.c $WASMVISION_C_COMPONENTS_PATH/wasmvision/platform_component_type.o \
        -Wl,--export=process \
        -Wl,--export=__data_end -Wl,--export=__heap_base \
        -Wl,--strip-all,--no-entry \
        -Wl,--unresolved-symbols=ignore-all \
        -nostdlib \