'Aseprite' is a pixel art software available for PC on Steam and the official website. It was initially published during 2001, although received a stable release on June 6th, 2014. The program was developed by David Capello, which allows the user to create 2D digital art and animations using a pixel-based style.

Official Description

Aseprite is a pixel-art tool to create 2D animations, sprites, and any kind of graphics for games.

Features:

• Compose sprites using layers & frames as separated concepts
• Create images in RGBA or Indexed color modes
• Open/Save GIF animations, sequence of PNG files, etc.
• A timeline where you can copy/move layers, frames, or specific images
• Animation tools: Real-time animation preview, onion skinning, tag frames
• Pixel art tools: shading, pixel perfect strokes, RotSprite rotation, tiled mode, filled contour
• Export/import sprite sheets
• A command line interface to automate conversion and sprite sheets generation
• Updates for the whole v1.x series up to v1.9.