Hiper-C is a language that is used in some OKI printers. It has a sort of binary CGM structure.

Hiper-C seems to be Oki's interpretation of Zenographics' ZjStream - Zenographics SuperPrint Zj Stream protocol. Have a look at the okidecoder program from the foo2hiperc package.

$ foo2hiperc-wrapper ~/testpage.ps | hipercdecode -h
     0: \033%-12345X@PJL
     f: @PJL RDYMSG DISPLAY = "Unknown"
    30: @PJL SET OKIJOBACCOUNTJOB USERID="Unknown" JOBNAME="Unknown"
    6e: @PJL SET OKIAUXJOBINFO DATA="DocumentName=Unknown"
    a2: @PJL SET OKIAUXJOBINFO DATA="ComputerName=dual.rkkda.org"
    dd: @PJL SET OKIAUXJOBINFO DATA="ReceptionTime=00:00:00 2013/03/23"
   11e: @PJL SET OKIAUTOTRAYSWITCH=ON
   13d: @PJL SET OKIPAPERSIZECHECK=ENABLE
   160: @PJL SET RESOLUTION=600
   179: @PJL SET PAPER=LETTER
   190: @PJL SET OKITRAYSEQUENCE=PAPERFEEDTRAY
   1b8: @PJL SET OKIPAPERFEED=TRAY1
   1d5: @PJL SET OKIMEDIATYPE = PLAIN
   1f4: @PJL SET LPARM:PCL OKIPRINTMARGIN=INCH1D6
   21f: @PJL SET COPIES=1
   232: @PJL SET QTY=1
   242: @PJL SET HIPERCEFFECTIVEBLOCKSIZE=4207500
   26d: @PJL ENTER LANGUAGE=HIPERC
   288: RECTYPE 0 (len=52,0x34 cnt=1), Page 1
   290:         BLKNUM 0, nbie=1, pn=3 [black] uc=0,17, wid=4992 ud=0,0
   2a4:         BLKNUM 1 (len=20), uncompressed=1, bie:
                DL = 48, D = 48, P = 49, - = 48, XY = 4992 x 6400
                L0 = 256, MX = 0, MY = 0
                Order   = 0 
                Options = 0 
                1 stripes, 0 layers, 49 planes
   2bc: RECTYPE 1 (len=159764,0x27014 cnt=1)
   2c4:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
   2cc:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
 272d0: RECTYPE 1 (len=159764,0x27014 cnt=2)
 272d8:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
 272e0:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
 4e2e4: RECTYPE 1 (len=159764,0x27014 cnt=3)
 4e2ec:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
 4e2f4:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
 752f8: RECTYPE 1 (len=159764,0x27014 cnt=4)
 75300:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
 75308:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
 9c30c: RECTYPE 1 (len=159764,0x27014 cnt=5)
 9c314:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
 9c31c:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
 c3320: RECTYPE 1 (len=159764,0x27014 cnt=6)
 c3328:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
 c3330:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
 ea334: RECTYPE 1 (len=159764,0x27014 cnt=7)
 ea33c:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
 ea344:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
111348: RECTYPE 1 (len=159764,0x27014 cnt=8)
111350:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
111358:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
13835c: RECTYPE 1 (len=159764,0x27014 cnt=9)
138364:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
13836c:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
15f370: RECTYPE 1 (len=159764,0x27014 cnt=10)
15f378:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
15f380:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
186384: RECTYPE 1 (len=159764,0x27014 cnt=11)
18638c:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
186394:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
1ad398: RECTYPE 1 (len=159764,0x27014 cnt=12)
1ad3a0:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
1ad3a8:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
1d43ac: RECTYPE 1 (len=159764,0x27014 cnt=13)
1d43b4:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
1d43bc:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
1fb3c0: RECTYPE 1 (len=159764,0x27014 cnt=14)
1fb3c8:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
1fb3d0:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
2223d4: RECTYPE 1 (len=159764,0x27014 cnt=15)
2223dc:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
2223e4:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
2493e8: RECTYPE 1 (len=159764,0x27014 cnt=16)
2493f0:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
2493f8:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
2703fc: RECTYPE 1 (len=159764,0x27014 cnt=17)
270404:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
27040c:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
297410: RECTYPE 1 (len=159764,0x27014 cnt=18)
297418:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
297420:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
2be424: RECTYPE 1 (len=159764,0x27014 cnt=19)
2be42c:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
2be434:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
2e5438: RECTYPE 1 (len=159764,0x27014 cnt=20)
2e5440:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
2e5448:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
30c44c: RECTYPE 1 (len=159764,0x27014 cnt=21)
30c454:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
30c45c:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
333460: RECTYPE 1 (len=159764,0x27014 cnt=22)
333468:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
333470:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
35a474: RECTYPE 1 (len=159764,0x27014 cnt=23)
35a47c:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
35a484:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
381488: RECTYPE 1 (len=159764,0x27014 cnt=24)
381490:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
381498:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
3a849c: RECTYPE 1 (len=159764,0x27014 cnt=25)
3a84a4:         BLKNUM 0 (len=4), plane=3, uc=0,0,0
3a84ac:         BLKNUM 1 (len=159744), Data=00 00 00 00 00 00 00 00 00 00 00 ...
3cf4b0: RECTYPE 255 (len=8,0x8 cnt=26)
3cf4b8: \033%-12345X@PJL
3cf4c7: @PJL EOJ NAME = "End "
3cf4de: \033%-12345X