Lavaflow is a Zenographics implementation of PCL - HP Page Description Language. It only supports raster graphics output.

$ foo2lava-wrapper ~/testpage.ps | lavadecode -h
     0: \033%-12345X@PJL JOB NAME="stdin"
    1f: \033%-12345X@PJL JOB USERNAME=""
    3d: \033%-12345X@PJL JOB TIMESTAMP="03/23/2013"
    66: \033%-12345X@PJL JOB OSINFO="Linux/3.6.11-4.fc16.i686"
    9a: \033%-12345X@PJL ENTER LANGUAGE=LAVAFLOW
    c0: \033E                   RESET
    c2: \033&l0S                DUPLEX: [off]
    c7: \033&l0G
    cc: \033&u1200D             X RESOLUTION: [1200]
    d4: \033&l1X                COPIES: [1]
    d9: \033&x1X                TRANSMIT ONCE COPIES: [1]
    de: \033&l0O                ORIENTATION: [port]
    e3: \033*r1U                NBIE: [1]
    e8: \033*g8W                BW/COLOR: [8]
                                fmt=2 np=1
                                BLACK:  X=1200, Y=600, unk=0, #=4(2)
    f5: \033*b1234M             COMPRESSION: [1234] (JBIG)
    fd: \033&l2A                PAGE SIZE: [letter]
   102: \033&l255H              PAPER SOURCE: [auto]
   109: \033&l0M                MEDIA TYPE: [plain]
   10e: \033&l0E                TOP MARGIN: [0]
   113: \033*r9792S             X RASTER: [9792,0x2640]
   11b: \033*r6400T             Y RASTER: [6400,0x1900]
   123: \033&l0U
   128: \033&l0Z
   12d: \033*p200X              X OFFSET: [200]
   134: \033*p200Y              Y OFFSET: [200]
   13b: \033*r1A                [Page 1]
   140: \033*b20V               [black]
                                DL = 0, D = 0, P = 1, - = 0, XY = 9792 x 6400
                                L0 = 128, MX = 0, MY = 0
                                Order   = 3  ILEAVE SMID
                                Options = 92  LRLTWO TPDON TPBON DPON
                                50 stripes, 0 layers, 1 planes
   15a: \033*b65536V            JBIG data (first) [65536,0x10000]
                         ff 02 c2 79 54 3e be e1 a0 de 08 9a b1 d2 c2 59
                        ... ae 88 ef a7 c7 96 d3 96 a6 d7 2c 06 38 75 22 44
 10163: \033*b26432W            JBIG data (end) [26432,0x6740]
                         0e 89 66 ce 01 41 41 41 41 41 41 41 41 41 41 41
                        ... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 168ac: \033*x3887138K          BLACK DOTS: [3887138]
 168b7: \033*x58781662W         BLACK WHITEDOTS: [58781662]
 168c3: \033*rC                 END PAGE
 168c7: \033&l0H                PAPER SOURCE: [eject]
 168cc: \033E                   RESET
 168ce: \033%-12345X

• PCL - HP Page Description Language
• foo2lava - a linux printer driver for LAVAFLOW protocol