How a GPU Turns One Pixel
Into a Full Image
A zero-to-hero visual journey through NVIDIA GPU architecture. Watch data flow from your CPU through Streaming Multiprocessors, CUDA threads, and memory hierarchies — all the way to your screen.
From JPEG on Disk
to Pixels on Screen
Every image you see passes through 5 distinct hardware and software stages. Click each step to understand exactly what happens.
CPU Loads the Image
Host → System RAM
Your CPU reads the image file from disk (JPEG/PNG), decodes it into raw pixel data (RGBA bytes), and stores it in system RAM. Each pixel is 4 bytes — Red, Green, Blue, Alpha.
uint8_t pixels[1920 * 1080 * 4]; // ~8MB
stbi_load("photo.jpg", pixels, ...);Speed vs. Size:
The Memory Pyramid
GPUs have 5 levels of memory, each trading speed for capacity. Understanding this pyramid is the key to writing fast GPU code.
Registers
Per Thread
Fastest storage. Each CUDA thread gets its own private registers — like a calculator's display. Disappears when the thread ends.
float r = pixel.r; // stored in registerExplore Every Transistor.
Understand Every Cycle.
Two interactive learning paths — pick your depth level and start exploring the hardware that powers modern computing.