If you were to load a PDF file with an embedded JBIG2 image stream: /Type /XObject /Subtype /Image /Width 2550 /Height 3305 /BitsPerComponent 1/ColorSpace /DeviceGray /Filter /Filter/DecodeParms << /jbig2Globals 13 0 R >> /Length 10 0 R /Name /X >>/X >> /X /X/X/JBIG/G2/X; /XX: X/XObject: XObject; XObject/Image; X/Image: X Object; X Object/Image/X:XObject; Y/X Object: X, XObject, X Object, X; X”]
Source: https://blog.talosintelligence.com/2009/02/have-nice-weekend-pdf-love.html