long-image-split-square
/
gm convert -list format.txt

$ gm convert -list format
   Format L  Mode  Description
--------------------------------------------------------------------------------
      3FR S  r--  Hasselblad Photo RAW
     8BIM P  rw-  Photoshop resource format
 8BIMTEXT P  rw-  Photoshop resource text format
8BIMWTEXT P  rw-  Photoshop resource wide text format
     APP1 P  rw-  Raw application information
 APP1JPEG P  rw-  Raw JPEG binary data
      ART S  rw-  PFS: 1st Publisher
      ARW S  r--  Sony Alpha DSLR RAW
      AVS U  rw+  AVS X image
        B S  rw+  Raw blue samples
  BIGTIFF P  rw+  Tagged Image File Format (64-bit offsets)
      BMP P  rw-  Microsoft Windows bitmap image
     BMP2 P  -w-  Microsoft Windows bitmap image v2
     BMP3 P  -w-  Microsoft Windows bitmap image v3
      BRF S  -w-  BRF ASCII Braille format
        C S  rw+  Raw cyan samples
    CACHE U  ---  Magick Persistent Cache image format
     CALS S  rw-  Continuous Acquisition and Life-cycle Support Type 1 image
            Specified in MIL-R-28002 and MIL-PRF-28002
  CAPTION P  r--  Image caption
      CIN S  rw-  Cineon Image File
     CMYK S  rw+  Raw cyan, magenta, yellow, and black samples
    CMYKA S  rw+  Raw cyan, magenta, yellow, black, and opacity samples
      CR2 S  r--  Canon Photo RAW
      CRW S  r--  Canon Photo RAW
      CUR S  r--  Microsoft Cursor Icon
      CUT S  r--  DR Halo
      DCM S  r--  Digital Imaging and Communications in Medicine image
            See http://medical.nema.org/ for information on DICOM.
      DCR S  r--  Kodak Photo RAW
      DCX S  rw+  ZSoft IBM PC multi-page Paintbrush
      DNG S  r--  Adobe Digital Negative
      DPX P  rw-  SMPTE 268M-2003 (DPX 2.0)
            See http://www.smtpe.org/ for information on DPX.
     EPDF P  rw-  Encapsulated Portable Document Format
      EPI P  rw-  Adobe Encapsulated PostScript Interchange format
      EPS P  rw-  Adobe Encapsulated PostScript
     EPS2 P  -w-  Adobe Level II Encapsulated PostScript
     EPS3 P  -w+  Adobe Level III Encapsulated PostScript
     EPSF P  rw-  Adobe Encapsulated PostScript
     EPSI P  rw-  Adobe Encapsulated PostScript Interchange format
      EPT P  rw-  Adobe Encapsulated PostScript with MS-DOS TIFF preview
     EPT2 P  rw-  Adobe Level II Encapsulated PostScript with MS-DOS TIFF preview
     EPT3 P  rw-  Adobe Level III Encapsulated PostScript with MS-DOS TIFF preview
      ERF S  r--  Epson RAW Format
     EXIF P  rw-  Exif digital camera binary data
      FAX P  rw+  Group 3 FAX (Not TIFF Group3 FAX!)
     FILE S  r--  Uniform Resource Locator (file://)
     FITS S  rw-  Flexible Image Transport System
  FRACTAL S  r--  Plasma fractal image
      FTP U  r--  Uniform Resource Locator (ftp://)
        G S  rw+  Raw green samples
      GIF P  rw+  CompuServe graphics interchange format (version 89a)
    GIF87 P  rw-  CompuServe graphics interchange format (version 87a)
 GRADIENT P  r--  Gradual passing from one shade to another
     GRAY S  rw+  Raw gray samples
    GRAYA S  rw+  Raw gray samples + alpha
HISTOGRAM P  -w-  Histogram of the image
      HRZ S  r--  HRZ: Slow scan TV
     HTML S  -w-  Hypertext Markup Language and a client-side image map
     HTTP U  r--  Uniform Resource Locator (http://)
      ICB S  rw+  Truevision Targa image
      ICC P  rw-  ICC Color Profile
      ICM P  rw-  ICC Color Profile
      ICO S  r--  Microsoft Icon
     ICON S  r--  Microsoft Icon
 IDENTITY P  r--  Hald CLUT identity image
    IMAGE P  r--  GraphicsMagick Embedded Image
     INFO S  -w+  Image descriptive information and statistics
     IPTC P  rw-  IPTC Newsphoto
 IPTCTEXT P  rw-  IPTC Newsphoto text format
IPTCWTEXT P  rw-  IPTC Newsphoto text format
   ISOBRL S  -w-  ISO/TR 11548-1 format
  ISOBRL6 S  -w-  ISO/TR 11548-1 format 6dot
      J2C S  rw-  JPEG-2000 Code Stream Syntax
      JNG S  rw-  JPEG Network Graphics (libpng 1.6.37, zlib 1.2.11)
            See http://www.libpng.org/pub/mng/ for information on JNG.
      JNX S  r--  JNX: Garmin tile storage format
      JP2 S  rw-  JPEG-2000 JP2 File Format Syntax
      JPC S  rw-  JPEG-2000 Code Stream Syntax
     JPEG P  rw-  Joint Photographic Experts Group JFIF format (IJG JPEG 80)
      JPG P  rw-  Joint Photographic Experts Group JFIF format (IJG JPEG 80)
        K S  rw+  Raw black samples
      K25 S  r--  Kodak Photo RAW
      KDC S  r--  Kodak Photo RAW
    LABEL P  r--  Image label
        M S  rw+  Raw magenta samples
      M2V S  -w+  MPEG Video Stream
      MAC S  r--  Mac Paint
      MAP U  rw-  Colormap intensities and indices
      MAT S  rw+  MATLAB Level 4.0-7.0 image formats
    MATTE S  -w+  MATTE raw opacity format
      MEF S  r--  Mamiya Photo RAW
     MIFF P  rw+  Magick Image File Format (GraphicsMagick 1.3.34, Zlib 1.2.11, BZlib)
      MNG S  rw+  Multiple-image Network Graphics (libpng 1.6.37, zlib 1.2.11)
            See http://www.libpng.org/pub/mng/ for information on MNG.
     MONO S  rw-  Bi-level bitmap in least-significant-byte first order
      MPC U  rw+  Magick Persistent Cache image format
     MPEG S  -w+  MPEG Video Stream
      MPG S  -w+  MPEG Video Stream
      MRW S  r--  Minolta Photo RAW
      MSL S  rw+  Magick Scripting Language
      MTV U  rw+  MTV Raytracing image format
      MVG S  rw-  Magick Vector Graphics
      NEF S  r--  Nikon Electronic Format
     NULL P  rw-  Constant image of uniform color
        O S  rw+  Raw opacity samples
      ORF S  r--  Olympus Photo RAW
      OTB S  rw-  On-the-air bitmap
       P7 S  rw+  Xv thumbnail format
      PAL S  rw-  16bit/pixel interleaved YUV
     PALM U  r--  Palm pixmap
      PAM P  rw+  Portable Arbitrary Map format
      PBM P  rw+  Portable bitmap format (black/white)
      PCD S  rw-  Photo CD
     PCDS S  rw-  Photo CD
      PCL S  -w+  Page Control Language
      PCT S  rw-  Apple Macintosh QuickDraw/PICT
      PCX S  rw-  ZSoft IBM PC Paintbrush
      PDB U  rw+  Palm Database ImageViewer Format
      PDF P  rw+  Portable Document Format
      PEF S  r--  Pentax Electronic File
      PFA P  r--  Postscript Type 1 font (ASCII) (FreeType 2.10.1)
      PFB P  r--  Postscript Type 1 font (binary) (FreeType 2.10.1)
      PGM P  rw+  Portable graymap format (gray scale)
      PGX S  rw-  JPEG-2000 VM Format
    PICON S  rw-  Personal Icon
     PICT S  rw-  Apple Macintosh QuickDraw/PICT
      PIX S  r--  Alias/Wavefront RLE image format
   PLASMA S  r--  Plasma fractal image
      PNG P  rw-  Portable Network Graphics (libpng 1.6.37, zlib 1.2.11)
            See http://www.libpng.org/ for information on PNG..
    PNG00 P  rw-  PNG that inherits type and depth from original (libpng 1.6.37, zlib 1.
2.11)
    PNG24 P  rw-  24-bit RGB PNG, opaque only (libpng 1.6.37, zlib 1.2.11)
    PNG32 P  rw-  32-bit RGBA PNG, semitransparency OK (libpng 1.6.37, zlib 1.2.11)
    PNG48 P  rw-  opaque or binary transparent 48-bit RGB (libpng 1.6.37, zlib 1.2.11)
    PNG64 P  rw-  opaque or transparent 64-bit RGBA (libpng 1.6.37, zlib 1.2.11)
     PNG8 P  rw-  8-bit indexed PNG, binary transparency only (libpng 1.6.37, zlib 1.2.1
1)
      PNM P  rw+  Portable anymap
      PPM P  rw+  Portable pixmap format (color)
  PREVIEW S  -w-  Show a preview an image enhancement, effect, or f/x
       PS P  rw+  Adobe PostScript
      PS2 P  -w+  Adobe Level II PostScript
      PS3 P  -w+  Adobe Level III PostScript
     PTIF S  rw+  Pyramid encoded TIFF
      PWP U  r--  Seattle Film Works
        R S  rw+  Raw red samples
      RAF S  r--  Fuji Photo RAW
      RAS S  rw+  SUN Rasterfile
      RGB S  rw+  Raw red, green, and blue samples
     RGBA S  rw+  Raw red, green, blue, and matte samples
      RLA U  r--  Alias/Wavefront image
      RLE U  r--  Utah Run length encoded image
      SCT U  r--  Scitex HandShake
      SFW U  r--  Seattle Film Works
      SGI S  rw-  Irix RGB image
    SHTML S  -w-  Hypertext Markup Language and a client-side image map
      SR2 S  r--  Sony Photo RAW
      SRF S  r--  Sony Photo RAW
  STEGANO S  r--  Steganographic image
      SUN S  rw+  SUN Rasterfile
      SVG S  r--  Scalable Vector Graphics (XML 2.9.10)
     SVGZ S  r--  Scalable Vector Graphics (ZIP compressed) (XML 2.9.10)
     TEXT S  rw+  ASCII Text
      TGA S  rw+  Truevision Targa image
     TIFF P  rw+  Tagged Image File Format (LIBTIFF, Version 4.1.0)
     TILE P  r--  Tile image with a texture
            Use the syntax "-size WIDTHxHEIGHT TILE:imagename" to tile the
            specified tile image over a canvas image of size WIDTHxHEIGHT.
      TIM S  r--  PSX TIM
    TOPOL S  r--  TOPOL X Image
      TTF P  r--  TrueType font (FreeType 2.10.1)
      TXT S  rw+  ASCII Text
     UBRL S  -w-  Unicode Text format
    UBRL6 S  -w-  Unicode Text format 6dot
      UIL U  -w-  X-Motif UIL table
     UYVY S  rw-  16bit/pixel interleaved YUV
      VDA S  rw+  Truevision Targa image
    VICAR S  rw-  VICAR rasterfile format
      VID S  rw+  Visual Image Directory
     VIFF S  rw+  Khoros Visualization image
      VST S  rw+  Truevision Targa image
     WBMP S  rw-  Wireless Bitmap (level 0) image
      WPG U  r--  Word Perfect Graphics
      X3F S  r--  Foveon X3 (Sigma/Polaroid) RAW
      XBM S  rw-  X Windows system bitmap (black/white)
       XC P  r--  Constant image uniform color
      XCF S  r--  GIMP image
      XMP P  rw-  Adobe XML metadata
      XPM S  rw-  X Windows system pixmap (color)
       XV S  rw+  Khoros Visualization image
        Y S  rw+  Raw yellow samples
      YUV S  rw-  CCIR 601 4:1:1 or 4:2:2 (8-bit only)

 Meaning of 'L': P=Primary, S=Stable, U=Unstable
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