For some file formats ExifTool helpfully copies the image width and height to File:ImageHeight, etc. But it does not do this for PNG files (and maybe others that I don't know about).
$exiftool -G *.png | egrep -i "width|height|orien|rotat"
[PNG] Image Width : 120
[PNG] Image Height : 120
$ exiftool -G 20221022_132527883_iOS.heic | egrep -i "width|height"
[File] Image Width : 4032
[File] Image Height : 3024
[EXIF] Exif Image Width : 4032
[EXIF] Exif Image Height : 3024
Yes, very true. Running through my sample files, here are all of the various possiblities for ImageWidth (with the -G0:1 option):
[APP8:SPIFF] Image Width
[ASF] Image Width
[Composite] Image Width
[DjVu] Image Width
[EXIF:ExifIFD] Image Width
[EXIF:IFD0] Image Width
[EXIF:IFD1] Image Width
[EXIF:IFD2] Image Width
[EXIF:IFD3] Image Width
[EXIF:IFD4] Image Width
[EXIF:IFD5] Image Width
[EXIF:IFD6] Image Width
[EXIF:IFD7] Image Width
[EXIF:IFD8] Image Width
[EXIF:IFD9] Image Width
[EXIF:IFD10] Image Width
[EXIF:IFD11] Image Width
[EXIF:IFD12] Image Width
[EXIF:IFD13] Image Width
[EXIF:ProfileIFD] Image Width
[EXIF:ProfileIFD1] Image Width
[EXIF:SRF6] Image Width
[EXIF:SubIFD] Image Width
[EXIF:SubIFD1] Image Width
[EXIF:SubIFD2] Image Width
[EXIF:SubIFD3] Image Width
[EXIF:SubIFD4] Image Width
[EXIF:SubIFD5] Image Width
[File] Image Width
[Flash] Image Width
[FlashPix] Image Width
[GIF] Image Width
[GIMP] Image Width
[H264] Image Width
[Jpeg2000] Image Width
[Lytro] Image Width
[MakerNotes:CanonRaw] Image Width
[MakerNotes:CIFF] Image Width
[MakerNotes:MinoltaRaw] Image Width
[MakerNotes:PhaseOne] Image Width
[MakerNotes:Track1] Image Width
[MakerNotes:Track2] Image Width
[MakerNotes:Track3] Image Width
[Matroska:Track1] Image Width
[MIFF] Image Width
[MNG] Image Width
[MPEG] Image Width
[MXF:Track1] Image Width
[MXF:Track2] Image Width
[MXF:Track3] Image Width
[MXF:Track9] Image Width
[MXF] Image Width
[PhotoCD] Image Width
[Photoshop] Image Width
[PNG] Image Width
[PSP] Image Width
[QuickTime:Track1] Image Width
[QuickTime:Track2] Image Width
[QuickTime:Track3] Image Width
[QuickTime:Track6] Image Width
[Red] Image Width
[RIFF] Image Width
[SigmaRaw] Image Width
[SVG] Image Width
[Theora] Image Width
[XMP:XMP-dc] Image Width
[XMP:XMP-exif] Image Width
[XMP:XMP-GDepth] Image Width
[XMP:XMP-tiff] Image Width
[XMP:XMP-tmp0] Image Width
The "File" group is generally used for file types where the image width/height information isn't part of the metadata. I suppose the JPEG ImageWidth/Height should really be an a "JPEG" group, but I don't think it would be good to move them at this point. Also, I have been using the File group more often recently for these tags because ExifTool now supports so many different formats and the number of groups was getting out of hand.
- Phil