DuckStation is a PlayStation emulator for Windows, macOS, Linux, and Android. It runs PS1 games with configurable graphics, virtual controllers, memory cards, and session controls. The program is free for noncommercial use under a Creative Commons license.
Games in DuckStation
DuckStation combines a BIOS image with game media to emulate the console. Users supply both inputs; the emulator includes neither games nor a BIOS. A BIOS from a different region than the game can cause compatibility problems.
The desktop library scans folders users choose, with an option to include subfolders. It recognizes game titles and can combine multiple discs into one library entry. DuckStation reads physical CDs and several image types:
- BIN/CUE, CHD, and single-track ECM images.
- MDS/MDF and CloneCD CCD images.
- Unencrypted PBP files.
List and grid views present the collection differently. The grid can show JPG or PNG covers that match a game’s title, filename, or serial number.
Mapping the console controls
DuckStation translates keyboard and gamepad input into PlayStation controller actions. On desktop, users select a virtual controller and apply automatic mapping. Manual mapping links a button or axis to the next key or controller input they press.
Digital and analog controller modes handle different games, while rumble passes back to the host controller. Per-game configurations retain controller choices for individual titles. Multitap emulation accepts up to eight controllers when a game supports that arrangement.
Mouse input can stand in for GunCon or Justifier lightguns. The Android app also offers touchscreen controls, with layout editing and scaling in its pause menu.
Changing the game picture
DuckStation offers hardware and software rendering. With a hardware renderer, the internal resolution control increases the resolution of three-dimensional polygons and lines. Texture filtering smooths textures that the renderer magnifies. True-colour mode disables dithering when it renders colour gradients.
PGXP geometry correction reduces unstable polygon positions and texture warping. Perspective texture correction works alongside geometry correction. These changes can conflict with particular games.
Downsampling reduces the image DuckStation renders before display. Separate aspect-ratio and scaling controls govern its final presentation. Widescreen rendering expands the view in compatible games, although other games can display incorrectly.
Cards and session states
DuckStation handles ordinary game saves through virtual memory cards. Per-game cards switch with the current title, while a shared-card option uses a card image that the user chooses. For multi-disc games, a separate setting lets every disc use one card.
The memory card editor moves saves between cards and imports other card formats.
Save states retain an emulation session for later loading. Users choose a state slot and save or restore it; preview screenshots help distinguish states. The desktop command line can also load a particular state file or a game’s resume state.
Rewind and runahead
DuckStation can periodically retain states while a game runs. Rewind returns to those earlier positions, and its settings control capture frequency and the number of states it retains.
Runahead follows a different process: it simulates ahead, then rolls back and replays to reduce input lag. Enabling runahead disables rewind. Separate pause and speed controls govern playback. DuckStation stretches audio timing when playback differs from normal emulation speed.
Replacing game textures
DuckStation can exchange game textures for images users supply. Users enable its texture cache and dumping, play through the relevant scene, and examine the resulting texture files. They then copy files they select into the replacements directory and edit them.
Replacement filenames identify the original textures, so matching names matter. After users enable replacement loading, the emulator uses those images during gameplay. PNG, JPG, and WebP replacements work with this system. Texture replacement remains experimental and does not work with every game.
The Android beta
DuckStation also offers a separate Android beta with a mobile interface that the developer has rewritten. Its touchscreen editor keeps different arrangements for portrait and landscape play. Settings search allows changes directly within matching results.
The beta’s transfer tools import or export folders and ZIP archives. Users choose data categories and overwrite behaviour before transferring them. Offline achievement tracking works in casual mode. Existing saves, memory cards, and BIOS files survive the change, but the beta does not migrate settings.
