Image Viewer in C

A minimal PPM (P6) image viewer written in C using SDL2.
The program reads a PPM image from stdin and renders it pixel-by-pixel using an SDL_Surface.

This project is focused on learning low-level image rendering and SDL basics.

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Tutorial : Video Tutorial Available(by Daniel Hirsch)

Supported Format

• PPM (P6 – binary)
• 8-bit RGB
• No scaling or color correction

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How It Works

1. Reads and ignores the PPM magic number (P6)
2. Reads image width and height
3. Reads raw RGB bytes (R G B per pixel)
4. Draws each pixel directly onto an SDL window surface

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Build

Make sure SDL2 is installed.

gcc image.c -o image `sdl2-config --cflags --libs`

Run

./image < image.ppm

Notes

1. The SDL window size matches the PPM image dimensions. Rendering is done on the CPU, one pixel at a time
2. Pixels are drawn using SDL_FillRect with a 1×1 SDL_Rect
3. Correct (x, y) mapping is required to avoid image rotation
4. An event loop is required to keep the window responsive