Adobe Photoshop image file
PSB is a file extension for an image file used by Adobe Photoshop. PSB files are a large document format similar to a PSD file but for a larger image size. The largest image size supported by a PSD file is 30,000 by 30,000 pixels.
PSD file support has to be enabled in Photoshop's Preferences pane first, then PSB files can be saved at an image size up to 300,000 by 300,000 pixels. PSB files can be opened by Adobe PhotoShop CS or later. PSB files can be exported as TIFF for compatibility with other software.
MIME type: application/x-photoshop
The PSB file extension is also associated with Pinnacle Sound Bank files.
Learn more about .PSB files:
Visit the Adobe web page.
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