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-rw-r--r--fitz/filt_faxd.c776
1 files changed, 0 insertions, 776 deletions
diff --git a/fitz/filt_faxd.c b/fitz/filt_faxd.c
deleted file mode 100644
index 8ac98f42..00000000
--- a/fitz/filt_faxd.c
+++ /dev/null
@@ -1,776 +0,0 @@
-#include "mupdf/fitz.h"
-
-/* Fax G3/G4 decoder */
-
-/* TODO: uncompressed */
-
-/*
-<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
-};
-
-/* White decoding table. */
-static const cfd_node cf_white_decode[] = {
- {256,12},{272,12},{29,8},{30,8},{45,8},{46,8},{22,7},{22,7},
- {23,7},{23,7},{47,8},{48,8},{13,6},{13,6},{13,6},{13,6},{20,7},
- {20,7},{33,8},{34,8},{35,8},{36,8},{37,8},{38,8},{19,7},{19,7},
- {31,8},{32,8},{1,6},{1,6},{1,6},{1,6},{12,6},{12,6},{12,6},{12,6},
- {53,8},{54,8},{26,7},{26,7},{39,8},{40,8},{41,8},{42,8},{43,8},
- {44,8},{21,7},{21,7},{28,7},{28,7},{61,8},{62,8},{63,8},{0,8},
- {320,8},{384,8},{10,5},{10,5},{10,5},{10,5},{10,5},{10,5},{10,5},
- {10,5},{11,5},{11,5},{11,5},{11,5},{11,5},{11,5},{11,5},{11,5},
- {27,7},{27,7},{59,8},{60,8},{288,9},{290,9},{18,7},{18,7},{24,7},
- {24,7},{49,8},{50,8},{51,8},{52,8},{25,7},{25,7},{55,8},{56,8},
- {57,8},{58,8},{192,6},{192,6},{192,6},{192,6},{1664,6},{1664,6},
- {1664,6},{1664,6},{448,8},{512,8},{292,9},{640,8},{576,8},{294,9},
- {296,9},{298,9},{300,9},{302,9},{256,7},{256,7},{2,4},{2,4},{2,4},
- {2,4},{2,4},{2,4},{2,4},{2,4},{2,4},{2,4},{2,4},{2,4},{2,4},{2,4},
- {2,4},{2,4},{3,4},{3,4},{3,4},{3,4},{3,4},{3,4},{3,4},{3,4},{3,4},
- {3,4},{3,4},{3,4},{3,4},{3,4},{3,4},{3,4},{128,5},{128,5},{128,5},
- {128,5},{128,5},{128,5},{128,5},{128,5},{8,5},{8,5},{8,5},{8,5},
- {8,5},{8,5},{8,5},{8,5},{9,5},{9,5},{9,5},{9,5},{9,5},{9,5},{9,5},
- {9,5},{16,6},{16,6},{16,6},{16,6},{17,6},{17,6},{17,6},{17,6},
- {4,4},{4,4},{4,4},{4,4},{4,4},{4,4},{4,4},{4,4},{4,4},{4,4},{4,4},
- {4,4},{4,4},{4,4},{4,4},{4,4},{5,4},{5,4},{5,4},{5,4},{5,4},{5,4},
- {5,4},{5,4},{5,4},{5,4},{5,4},{5,4},{5,4},{5,4},{5,4},{5,4},
- {14,6},{14,6},{14,6},{14,6},{15,6},{15,6},{15,6},{15,6},{64,5},
- {64,5},{64,5},{64,5},{64,5},{64,5},{64,5},{64,5},{6,4},{6,4},
- {6,4},{6,4},{6,4},{6,4},{6,4},{6,4},{6,4},{6,4},{6,4},{6,4},{6,4},
- {6,4},{6,4},{6,4},{7,4},{7,4},{7,4},{7,4},{7,4},{7,4},{7,4},{7,4},
- {7,4},{7,4},{7,4},{7,4},{7,4},{7,4},{7,4},{7,4},{-2,3},{-2,3},
- {-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},
- {-1,0},{-1,0},{-1,0},{-1,0},{-3,4},{1792,3},{1792,3},{1984,4},
- {2048,4},{2112,4},{2176,4},{2240,4},{2304,4},{1856,3},{1856,3},
- {1920,3},{1920,3},{2368,4},{2432,4},{2496,4},{2560,4},{1472,1},
- {1536,1},{1600,1},{1728,1},{704,1},{768,1},{832,1},{896,1},
- {960,1},{1024,1},{1088,1},{1152,1},{1216,1},{1280,1},{1344,1},
- {1408,1}
-};
-
-/* Black decoding table. */
-static const cfd_node cf_black_decode[] = {
- {128,12},{160,13},{224,12},{256,12},{10,7},{11,7},{288,12},{12,7},
- {9,6},{9,6},{8,6},{8,6},{7,5},{7,5},{7,5},{7,5},{6,4},{6,4},{6,4},
- {6,4},{6,4},{6,4},{6,4},{6,4},{5,4},{5,4},{5,4},{5,4},{5,4},{5,4},
- {5,4},{5,4},{1,3},{1,3},{1,3},{1,3},{1,3},{1,3},{1,3},{1,3},{1,3},
- {1,3},{1,3},{1,3},{1,3},{1,3},{1,3},{1,3},{4,3},{4,3},{4,3},{4,3},
- {4,3},{4,3},{4,3},{4,3},{4,3},{4,3},{4,3},{4,3},{4,3},{4,3},{4,3},
- {4,3},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},
- {3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},
- {3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},{3,2},
- {2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},
- {2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},
- {2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},{2,2},
- {-2,4},{-2,4},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},
- {-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-3,5},{1792,4},
- {1792,4},{1984,5},{2048,5},{2112,5},{2176,5},{2240,5},{2304,5},
- {1856,4},{1856,4},{1920,4},{1920,4},{2368,5},{2432,5},{2496,5},
- {2560,5},{18,3},{18,3},{18,3},{18,3},{18,3},{18,3},{18,3},{18,3},
- {52,5},{52,5},{640,6},{704,6},{768,6},{832,6},{55,5},{55,5},
- {56,5},{56,5},{1280,6},{1344,6},{1408,6},{1472,6},{59,5},{59,5},
- {60,5},{60,5},{1536,6},{1600,6},{24,4},{24,4},{24,4},{24,4},
- {25,4},{25,4},{25,4},{25,4},{1664,6},{1728,6},{320,5},{320,5},
- {384,5},{384,5},{448,5},{448,5},{512,6},{576,6},{53,5},{53,5},
- {54,5},{54,5},{896,6},{960,6},{1024,6},{1088,6},{1152,6},{1216,6},
- {64,3},{64,3},{64,3},{64,3},{64,3},{64,3},{64,3},{64,3},{13,1},
- {13,1},{13,1},{13,1},{13,1},{13,1},{13,1},{13,1},{13,1},{13,1},
- {13,1},{13,1},{13,1},{13,1},{13,1},{13,1},{23,4},{23,4},{50,5},
- {51,5},{44,5},{45,5},{46,5},{47,5},{57,5},{58,5},{61,5},{256,5},
- {16,3},{16,3},{16,3},{16,3},{17,3},{17,3},{17,3},{17,3},{48,5},
- {49,5},{62,5},{63,5},{30,5},{31,5},{32,5},{33,5},{40,5},{41,5},
- {22,4},{22,4},{14,1},{14,1},{14,1},{14,1},{14,1},{14,1},{14,1},
- {14,1},{14,1},{14,1},{14,1},{14,1},{14,1},{14,1},{14,1},{14,1},
- {15,2},{15,2},{15,2},{15,2},{15,2},{15,2},{15,2},{15,2},{128,5},
- {192,5},{26,5},{27,5},{28,5},{29,5},{19,4},{19,4},{20,4},{20,4},
- {34,5},{35,5},{36,5},{37,5},{38,5},{39,5},{21,4},{21,4},{42,5},
- {43,5},{0,3},{0,3},{0,3},{0,3}
-};
-
-/* 2-D decoding table. */
-static const cfd_node cf_2d_decode[] = {
- {128,11},{144,10},{6,7},{0,7},{5,6},{5,6},{1,6},{1,6},{-4,4},
- {-4,4},{-4,4},{-4,4},{-4,4},{-4,4},{-4,4},{-4,4},{-5,3},{-5,3},
- {-5,3},{-5,3},{-5,3},{-5,3},{-5,3},{-5,3},{-5,3},{-5,3},{-5,3},
- {-5,3},{-5,3},{-5,3},{-5,3},{-5,3},{4,3},{4,3},{4,3},{4,3},{4,3},
- {4,3},{4,3},{4,3},{4,3},{4,3},{4,3},{4,3},{4,3},{4,3},{4,3},{4,3},
- {2,3},{2,3},{2,3},{2,3},{2,3},{2,3},{2,3},{2,3},{2,3},{2,3},{2,3},
- {2,3},{2,3},{2,3},{2,3},{2,3},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},
- {3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},
- {3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},
- {3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},
- {3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},
- {3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},{3,1},
- {3,1},{3,1},{3,1},{-2,4},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},
- {-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},
- {-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-1,0},{-3,3}
-};
-
-/* Uncompressed decoding table. */
-static const cfd_node cf_uncompressed_decode[] = {
- {64,12},{5,6},{4,5},{4,5},{3,4},{3,4},{3,4},{3,4},{2,3},{2,3},
- {2,3},{2,3},{2,3},{2,3},{2,3},{2,3},{1,2},{1,2},{1,2},{1,2},{1,2},
- {1,2},{1,2},{1,2},{1,2},{1,2},{1,2},{1,2},{1,2},{1,2},{1,2},{1,2},
- {0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},
- {0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},
- {0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},{0,1},
- {-1,0},{-1,0},{8,6},{9,6},{6,5},{6,5},{7,5},{7,5},{4,4},{4,4},
- {4,4},{4,4},{5,4},{5,4},{5,4},{5,4},{2,3},{2,3},{2,3},{2,3},{2,3},
- {2,3},{2,3},{2,3},{3,3},{3,3},{3,3},{3,3},{3,3},{3,3},{3,3},{3,3},
- {0,2},{0,2},{0,2},{0,2},{0,2},{0,2},{0,2},{0,2},{0,2},{0,2},{0,2},
- {0,2},{0,2},{0,2},{0,2},{0,2},{1,2},{1,2},{1,2},{1,2},{1,2},{1,2},
- {1,2},{1,2},{1,2},{1,2},{1,2},{1,2},{1,2},{1,2},{1,2},{1,2}
-};
-
-/* bit magic */
-
-static inline int getbit(const unsigned char *buf, int x)
-{
- return ( buf[x >> 3] >> ( 7 - (x & 7) ) ) & 1;
-}
-
-static const unsigned char mask[8] = {
- 0x7F, 0x3F, 0x1F, 0x0F, 0x07, 0x03, 0x01, 0
-};
-
-static const unsigned char clz[256] = {
- 8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,
- 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
- 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
- 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
-};
-
-static inline int
-find_changing(const unsigned char *line, int x, int w)
-{
- int a, b, m, W;
-
- if (!line)
- return w;
-
- /* We assume w > 0, -1 <= x < w */
- if (x < 0)
- {
- x = 0;
- m = 0xFF;
- }
- else
- {
- /* Mask out the bits we've already used (including the one
- * we started from) */
- m = mask[x & 7];
- }
- /* We have 'w' pixels (bits) in line. The last pixel that can be
- * safely accessed is the (w-1)th bit of line.
- * By taking W = w>>3, we know that the first W bytes of line are
- * full, with w&7 stray bits following. */
- W = w>>3;
- x >>= 3;
- a = line[x]; /* Safe as x < w => x <= w-1 => x>>3 <= (w-1)>>3 */
- b = a ^ (a>>1);
- b &= m;
- if (x >= W)
- {
- /* Within the last byte already */
- x = (x<<3) + clz[b];
- if (x > w)
- x = w;
- return x;
- }
- while (b == 0)
- {
- if (++x >= W)
- goto nearend;
- b = a & 1;
- a = line[x];
- b = (b<<7) ^ a ^ (a>>1);
- }
- return (x<<3) + clz[b];
-nearend:
- /* We have less than a byte to go. If no stray bits, exit now. */
- if ((x<<3) == w)
- return w;
- b = a&1;
- a = line[x];
- b = (b<<7) ^ a ^ (a>>1);
- x = (x<<3) + clz[b];
- if (x > w)
- x = w;
- return x;
-}
-
-static inline int
-find_changing_color(const unsigned char *line, int x, int w, int color)
-{
- if (!line || x >= w)
- return w;
-
- x = find_changing(line, (x > 0 || !color) ? x : -1, w);
-
- if (x < w && getbit(line, x) != color)
- x = find_changing(line, x, w);
-
- return x;
-}
-
-static const unsigned char lm[8] = {
- 0xFF, 0x7F, 0x3F, 0x1F, 0x0F, 0x07, 0x03, 0x01
-};
-
-static const unsigned char rm[8] = {
- 0x00, 0x80, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC, 0xFE
-};
-
-static inline void setbits(unsigned char *line, int x0, int x1)
-{
- int a0, a1, b0, b1, a;
-
- if (x1 <= x0)
- return;
-
- a0 = x0 >> 3;
- a1 = x1 >> 3;
-
- b0 = x0 & 7;
- b1 = x1 & 7;
-
- if (a0 == a1)
- {
- if (b1)
- line[a0] |= lm[b0] & rm[b1];
- }
- else
- {
- line[a0] |= lm[b0];
- for (a = a0 + 1; a < a1; a++)
- line[a] = 0xFF;
- if (b1)
- line[a1] |= rm[b1];
- }
-}
-
-typedef struct fz_faxd_s fz_faxd;
-
-enum
-{
- STATE_NORMAL, /* neutral state, waiting for any code */
- STATE_MAKEUP, /* got a 1d makeup code, waiting for terminating code */
- STATE_EOL, /* at eol, needs output buffer space */
- STATE_H1, STATE_H2, /* in H part 1 and 2 (both makeup and terminating codes) */
- STATE_DONE /* all done */
-};
-
-struct fz_faxd_s
-{
- fz_context *ctx;
- fz_stream *chain;
-
- int k;
- int end_of_line;
- int encoded_byte_align;
- int columns;
- int rows;
- int end_of_block;
- int black_is_1;
-
- int stride;
- int ridx;
-
- int bidx;
- unsigned int word;
-
- int stage;
-
- int a, c, dim, eolc;
- unsigned char *ref;
- unsigned char *dst;
- unsigned char *rp, *wp;
-};
-
-static inline void eat_bits(fz_faxd *fax, int nbits)
-{
- fax->word <<= nbits;
- fax->bidx += nbits;
-}
-
-static int
-fill_bits(fz_faxd *fax)
-{
- while (fax->bidx >= 8)
- {
- int c = fz_read_byte(fax->chain);
- if (c == EOF)
- return EOF;
- fax->bidx -= 8;
- fax->word |= c << fax->bidx;
- }
- return 0;
-}
-
-static int
-get_code(fz_faxd *fax, const cfd_node *table, int initialbits)
-{
- unsigned int word = fax->word;
- int tidx = word >> (32 - initialbits);
- int val = table[tidx].val;
- int nbits = table[tidx].nbits;
-
- if (nbits > initialbits)
- {
- int mask = (1 << (32 - initialbits)) - 1;
- tidx = val + ((word & mask) >> (32 - nbits));
- val = table[tidx].val;
- nbits = initialbits + table[tidx].nbits;
- }
-
- eat_bits(fax, nbits);
-
- return val;
-}
-
-/* decode one 1d code */
-static void
-dec1d(fz_context *ctx, fz_faxd *fax)
-{
- int code;
-
- if (fax->a == -1)
- fax->a = 0;
-
- if (fax->c)
- code = get_code(fax, cf_black_decode, cfd_black_initial_bits);
- else
- code = get_code(fax, cf_white_decode, cfd_white_initial_bits);
-
- if (code == UNCOMPRESSED)
- fz_throw(ctx, FZ_ERROR_GENERIC, "uncompressed data in faxd");
-
- if (code < 0)
- fz_throw(ctx, FZ_ERROR_GENERIC, "negative code in 1d faxd");
-
- if (fax->a + code > fax->columns)
- fz_throw(ctx, FZ_ERROR_GENERIC, "overflow in 1d faxd");
-
- if (fax->c)
- setbits(fax->dst, fax->a, fax->a + code);
-
- fax->a += code;
-
- if (code < 64)
- {
- fax->c = !fax->c;
- fax->stage = STATE_NORMAL;
- }
- else
- fax->stage = STATE_MAKEUP;
-}
-
-/* decode one 2d code */
-static void
-dec2d(fz_context *ctx, fz_faxd *fax)
-{
- int code, b1, b2;
-
- if (fax->stage == STATE_H1 || fax->stage == STATE_H2)
- {
- if (fax->a == -1)
- fax->a = 0;
-
- if (fax->c)
- code = get_code(fax, cf_black_decode, cfd_black_initial_bits);
- else
- code = get_code(fax, cf_white_decode, cfd_white_initial_bits);
-
- if (code == UNCOMPRESSED)
- fz_throw(ctx, FZ_ERROR_GENERIC, "uncompressed data in faxd");
-
- if (code < 0)
- fz_throw(ctx, FZ_ERROR_GENERIC, "negative code in 2d faxd");
-
- if (fax->a + code > fax->columns)
- fz_throw(ctx, FZ_ERROR_GENERIC, "overflow in 2d faxd");
-
- if (fax->c)
- setbits(fax->dst, fax->a, fax->a + code);
-
- fax->a += code;
-
- if (code < 64)
- {
- fax->c = !fax->c;
- if (fax->stage == STATE_H1)
- fax->stage = STATE_H2;
- else if (fax->stage == STATE_H2)
- fax->stage = STATE_NORMAL;
- }
-
- return;
- }
-
- code = get_code(fax, cf_2d_decode, cfd_2d_initial_bits);
-
- switch (code)
- {
- case H:
- fax->stage = STATE_H1;
- break;
-
- case P:
- b1 = find_changing_color(fax->ref, fax->a, fax->columns, !fax->c);
- if (b1 >= fax->columns)
- b2 = fax->columns;
- else
- b2 = find_changing(fax->ref, b1, fax->columns);
- if (fax->c) setbits(fax->dst, fax->a, b2);
- fax->a = b2;
- break;
-
- case V0:
- b1 = find_changing_color(fax->ref, fax->a, fax->columns, !fax->c);
- if (fax->c) setbits(fax->dst, fax->a, b1);
- fax->a = b1;
- fax->c = !fax->c;
- break;
-
- case VR1:
- b1 = 1 + find_changing_color(fax->ref, fax->a, fax->columns, !fax->c);
- if (b1 >= fax->columns) b1 = fax->columns;
- if (fax->c) setbits(fax->dst, fax->a, b1);
- fax->a = b1;
- fax->c = !fax->c;
- break;
-
- case VR2:
- b1 = 2 + find_changing_color(fax->ref, fax->a, fax->columns, !fax->c);
- if (b1 >= fax->columns) b1 = fax->columns;
- if (fax->c) setbits(fax->dst, fax->a, b1);
- fax->a = b1;
- fax->c = !fax->c;
- break;
-
- case VR3:
- b1 = 3 + find_changing_color(fax->ref, fax->a, fax->columns, !fax->c);
- if (b1 >= fax->columns) b1 = fax->columns;
- if (fax->c) setbits(fax->dst, fax->a, b1);
- fax->a = b1;
- fax->c = !fax->c;
- break;
-
- case VL1:
- b1 = -1 + find_changing_color(fax->ref, fax->a, fax->columns, !fax->c);
- if (b1 < 0) b1 = 0;
- if (fax->c) setbits(fax->dst, fax->a, b1);
- fax->a = b1;
- fax->c = !fax->c;
- break;
-
- case VL2:
- b1 = -2 + find_changing_color(fax->ref, fax->a, fax->columns, !fax->c);
- if (b1 < 0) b1 = 0;
- if (fax->c) setbits(fax->dst, fax->a, b1);
- fax->a = b1;
- fax->c = !fax->c;
- break;
-
- case VL3:
- b1 = -3 + find_changing_color(fax->ref, fax->a, fax->columns, !fax->c);
- if (b1 < 0) b1 = 0;
- if (fax->c) setbits(fax->dst, fax->a, b1);
- fax->a = b1;
- fax->c = !fax->c;
- break;
-
- case UNCOMPRESSED:
- fz_throw(ctx, FZ_ERROR_GENERIC, "uncompressed data in faxd");
-
- case ERROR:
- fz_throw(ctx, FZ_ERROR_GENERIC, "invalid code in 2d faxd");
-
- default:
- fz_throw(ctx, FZ_ERROR_GENERIC, "invalid code in 2d faxd (%d)", code);
- }
-}
-
-static int
-read_faxd(fz_stream *stm, unsigned char *buf, int len)
-{
- fz_faxd *fax = stm->state;
- unsigned char *p = buf;
- unsigned char *ep = buf + len;
- unsigned char *tmp;
-
- if (fax->stage == STATE_DONE)
- return 0;
-
- if (fax->stage == STATE_EOL)
- goto eol;
-
-loop:
-
- if (fill_bits(fax))
- {
- if (fax->bidx > 31)
- {
- if (fax->a > 0)
- goto eol;
- goto rtc;
- }
- }
-
- if ((fax->word >> (32 - 12)) == 0)
- {
- eat_bits(fax, 1);
- goto loop;
- }
-
- if ((fax->word >> (32 - 12)) == 1)
- {
- eat_bits(fax, 12);
- fax->eolc ++;
-
- if (fax->k > 0)
- {
- if (fax->a == -1)
- fax->a = 0;
- if ((fax->word >> (32 - 1)) == 1)
- fax->dim = 1;
- else
- fax->dim = 2;
- eat_bits(fax, 1);
- }
- }
- else if (fax->k > 0 && fax->a == -1)
- {
- fax->a = 0;
- if ((fax->word >> (32 - 1)) == 1)
- fax->dim = 1;
- else
- fax->dim = 2;
- eat_bits(fax, 1);
- }
- else if (fax->dim == 1)
- {
- fax->eolc = 0;
- dec1d(stm->ctx, fax);
- }
- else if (fax->dim == 2)
- {
- fax->eolc = 0;
- dec2d(stm->ctx, fax);
- }
-
- /* no eol check after makeup codes nor in the middle of an H code */
- if (fax->stage == STATE_MAKEUP || fax->stage == STATE_H1 || fax->stage == STATE_H2)
- goto loop;
-
- /* check for eol conditions */
- if (fax->eolc || fax->a >= fax->columns)
- {
- if (fax->a > 0)
- goto eol;
- if (fax->eolc == (fax->k < 0 ? 2 : 6))
- goto rtc;
- }
-
- goto loop;
-
-eol:
- fax->stage = STATE_EOL;
-
- if (fax->black_is_1)
- {
- while (fax->rp < fax->wp && p < ep)
- *p++ = *fax->rp++;
- }
- else
- {
- while (fax->rp < fax->wp && p < ep)
- *p++ = *fax->rp++ ^ 0xff;
- }
-
- if (fax->rp < fax->wp)
- return p - buf;
-
- tmp = fax->ref;
- fax->ref = fax->dst;
- fax->dst = tmp;
- memset(fax->dst, 0, fax->stride);
-
- fax->rp = fax->dst;
- fax->wp = fax->dst + fax->stride;
-
- fax->stage = STATE_NORMAL;
- fax->c = 0;
- fax->a = -1;
- fax->ridx ++;
-
- if (!fax->end_of_block && fax->rows)
- {
- if (fax->ridx >= fax->rows)
- goto rtc;
- }
-
- /* we have not read dim from eol, make a guess */
- if (fax->k > 0 && !fax->eolc && fax->a == -1)
- {
- if (fax->ridx % fax->k == 0)
- fax->dim = 1;
- else
- fax->dim = 2;
- }
-
- /* if end_of_line & encoded_byte_align, EOLs are *not* optional */
- if (fax->encoded_byte_align)
- {
- if (fax->end_of_line)
- eat_bits(fax, (12 - fax->bidx) & 7);
- else
- eat_bits(fax, (8 - fax->bidx) & 7);
- }
-
- /* no more space in output, don't decode the next row yet */
- if (p == buf + len)
- return p - buf;
-
- goto loop;
-
-rtc:
- fax->stage = STATE_DONE;
- return p - buf;
-}
-
-static void
-close_faxd(fz_context *ctx, void *state_)
-{
- fz_faxd *fax = (fz_faxd *)state_;
- int i;
-
- /* if we read any extra bytes, try to put them back */
- i = (32 - fax->bidx) / 8;
- while (i--)
- fz_unread_byte(fax->chain);
-
- fz_close(fax->chain);
- fz_free(ctx, fax->ref);
- fz_free(ctx, fax->dst);
- fz_free(ctx, fax);
-}
-
-/* Default: columns = 1728, end_of_block = 1, the rest = 0 */
-fz_stream *
-fz_open_faxd(fz_stream *chain,
- int k, int end_of_line, int encoded_byte_align,
- int columns, int rows, int end_of_block, int black_is_1)
-{
- fz_context *ctx = chain->ctx;
- fz_faxd *fax = NULL;
-
- fz_var(fax);
-
- fz_try(ctx)
- {
- fax = fz_malloc_struct(ctx, fz_faxd);
- fax->chain = chain;
-
- fax->ref = NULL;
- fax->dst = NULL;
-
- fax->k = k;
- fax->end_of_line = end_of_line;
- fax->encoded_byte_align = encoded_byte_align;
- fax->columns = columns;
- fax->rows = rows;
- fax->end_of_block = end_of_block;
- fax->black_is_1 = black_is_1;
-
- fax->stride = ((fax->columns - 1) >> 3) + 1;
- fax->ridx = 0;
- fax->bidx = 32;
- fax->word = 0;
-
- fax->stage = STATE_NORMAL;
- fax->a = -1;
- fax->c = 0;
- fax->dim = fax->k < 0 ? 2 : 1;
- fax->eolc = 0;
-
- fax->ref = fz_malloc(ctx, fax->stride);
- fax->dst = fz_malloc(ctx, fax->stride);
- fax->rp = fax->dst;
- fax->wp = fax->dst + fax->stride;
-
- memset(fax->ref, 0, fax->stride);
- memset(fax->dst, 0, fax->stride);
- }
- fz_catch(ctx)
- {
- if (fax)
- {
- fz_free(ctx, fax->dst);
- fz_free(ctx, fax->ref);
- }
- fz_free(ctx, fax);
- fz_close(chain);
- fz_rethrow(ctx);
- }
-
- return fz_new_stream(ctx, fax, read_faxd, close_faxd);
-}