diff options
Diffstat (limited to 'fitz/filt_faxd.c')
| -rw-r--r-- | fitz/filt_faxd.c | 776 |
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); -} |