The SEQ format is associated with bitmap images created on Atari ST computers. Such devices were very popular during the 1980s and 1990s, being one of the first types of computers to gain a wide audience among home users. Similar formats include PIC and PAC. SEQ files are currently considered old and obsolete, so opening them is probably difficult.
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 GBR PCT MIF PLT PCL SVG WPG CIN DCX DIS HRU MTV PRC RAD PIC RLA QRT SGI XBM XPM SWF CAL PSD JXR BPG APNG DDS SVGZ CG4 FLIF