dmtxread -l | no explanation what the countless formats mean

[morciej]

dmtxwrite -l shows this encouraging list of formats, but there are no pointers or explanations of what they mean.
Where are they documented? If they are listed somewhere, maybe it should be made more obvious where to find them?

    3FR        DDS         GV     MAGICK        PCL        PWP        TTC
    3G2      DFONT          H        MAP        PCT RADIAL-GRADIENT        TTF
    3GP       DJVU       HALD       MASK        PCX        RAF        TXT
    AAI        DNG        HDR        MAT        PDB        RAS       UBRL
     AI        DOT  HISTOGRAM      MATTE        PDF        RAW      UBRL6
    ART        DPX        HRZ        MEF       PDFA        RGB        UIL
    ARW       DXT1        HTM       MIFF        PEF       RGBA       UYVY
    AVI       DXT5       HTML        MKV        PES       RGBO        VDA
    AVS       EPDF       HTTP        MNG        PFA        RGF      VICAR
    BGR        EPI      HTTPS       MONO        PFB        RLA        VID
   BGRA        EPS        ICB        MOV        PFM        RLE       VIFF
   BGRO       EPS2        ICO        MP4        PGM        RMF       VIPS
    BIE       EPS3       ICON        MPC        PGX        RW2        VST
    BMP       EPSF        IIQ       MPEG      PICON        SCR       WBMP
   BMP2       EPSI       INFO        MPG       PICT        SCT       WEBP
   BMP3        EPT     INLINE        MRW        PIX        SFW        WMF
    BRF       EPT2        IPL        MSL      PJPEG        SGI        WMV
    CAL       EPT3     ISOBRL       MSVG     PLASMA      SHTML        WMZ
   CALS        ERF    ISOBRL6        MTV        PNG        SIX        WPG
 CANVAS        EXR        JBG        MVG      PNG00      SIXEL          X
CAPTION        FAX       JBIG        NEF      PNG24 SPARSE-COLOR        X3F
    CIN       FILE        JNG        NRW      PNG32        SR2        XBM
    CIP       FITS        JNX       NULL      PNG48        SRF         XC
   CLIP    FRACTAL        JPE        ORF      PNG64    STEGANO        XCF
   CMYK        FTP       JPEG        OTB       PNG8        SUN        XPM
  CMYKA        FTS        JPG        OTF        PNM        SVG        XPS
    CR2         G3        JPS        PAL        PPM       SVGZ         XV
    CRW         G4       JSON       PALM    PREVIEW       TEXT        XWD
    CUR        GIF        K25        PAM         PS        TGA      YCbCr
    CUT      GIF87        KDC      PANGO        PS2  THUMBNAIL     YCbCrA
   DATA   GRADIENT      LABEL    PATTERN        PS3       TIFF        YUV
    DCM       GRAY        M2V        PBM        PSB     TIFF64           
    DCR      GRAYA        M4V        PCD        PSD       TILE           
    DCX     GROUP4        MAC       PCDS       PTIF        TIM