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author | Tor Andersson <tor@ghostscript.com> | 2005-03-30 08:30:22 +0200 |
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committer | Tor Andersson <tor@ghostscript.com> | 2005-03-30 08:30:22 +0200 |
commit | ee154f16bd09a43359967f7e7b86c3677c09461d (patch) | |
tree | 08896cfa9ff55e05bfe7855965c620d45115d4d5 /stream/filt_faxd.h | |
parent | 460ad7040d67a4a93a153f98095ff952a2b15d37 (diff) | |
download | mupdf-ee154f16bd09a43359967f7e7b86c3677c09461d.tar.xz |
rename part 1 -- files
Diffstat (limited to 'stream/filt_faxd.h')
-rw-r--r-- | stream/filt_faxd.h | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/stream/filt_faxd.h b/stream/filt_faxd.h new file mode 100644 index 00000000..9f3fb470 --- /dev/null +++ b/stream/filt_faxd.h @@ -0,0 +1,61 @@ +/* Fax G3/G4 tables */ + +/* +<raph> the first 2^(initialbits) entries map bit patterns to decodes +<raph> let's say initial_bits is 8 for the sake of example +<raph> and that the code is 1001 +<raph> that means that entries 0x90 .. 0x9f have the entry { val, 4 } +<raph> because those are all the bytes that start with the code +<raph> and the 4 is the length of the code +... if (n_bits > initial_bits) ... +<raph> anyway, in that case, it basically points to a mini table +<raph> the n_bits is the maximum length of all codes beginning with that byte +<raph> so 2^(n_bits - initial_bits) is the size of the mini-table +<raph> peter came up with this, and it makes sense +*/ + +typedef struct cfd_node_s cfd_node; + +struct cfd_node_s +{ + short val; + short nbits; +}; + +enum +{ + cfd_white_initial_bits = 8, + cfd_black_initial_bits = 7, + cfd_2d_initial_bits = 7, + cfd_uncompressed_initial_bits = 6 /* must be 6 */ +}; + +/* non-run codes in tables */ +enum +{ + ERROR = -1, + ZEROS = -2, /* EOL follows, possibly with more padding first */ + UNCOMPRESSED = -3 +}; + +/* semantic codes for cf_2d_decode */ +enum +{ + P = -4, + H = -5, + VR3 = 0, + VR2 = 1, + VR1 = 2, + V0 = 3, + VL1 = 4, + VL2 = 5, + VL3 = 6 +}; + +/* Decoding tables */ + +extern const cfd_node cf_white_decode[]; +extern const cfd_node cf_black_decode[]; +extern const cfd_node cf_2d_decode[]; +extern const cfd_node cf_uncompressed_decode[]; + |