The TUB format is associated with Corel PaintShop Pro, which is one of the most popular programs used for advanced image editing and drawing. TUB files are also known as "picture tubes" and represent basic images with no background that can be used for creating more complex images. TUBs are probably impossible to open outside PaintShop, so in case you don't have it installed, the best option is to have them converted to more accessible formats.
The quick and simple way to handle your files is to get a quality piece of software, such as reaConverter. This software is extremely efficient in managing a wide range of batch conversions. As you will soon realize, reaConverter will help you avoid spending countless hours trying to figure out how to convert multiple TUB files as once.
JPEG JPG PNG GIF TIFF TIF BMP ICO EMF WMF AI PDF EPS PS EPI WEBP WEBPLL JP2 PCX TGA DWG DWF DXF DGN WMZ CGM DRW SHP GBR PCT MIF PLT PCL SVG WPG CIN DCX DIS HRU MTV PRC RAD PIC RLA QRT SGI XBM XPM SWF CAL FAX FITS PSD PGM JXR BPG APNG DDS SVGZ CG4 FLIF AVIF