diff options
Diffstat (limited to 'fitz/filt_predict.c')
| -rw-r--r-- | fitz/filt_predict.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/fitz/filt_predict.c b/fitz/filt_predict.c index e68743d3..b82c1281 100644 --- a/fitz/filt_predict.c +++ b/fitz/filt_predict.c @@ -31,6 +31,7 @@ static inline int getcomponent(unsigned char *line, int x, int bpc) case 2: return (line[x >> 2] >> ( ( 3 - (x & 3) ) << 1 ) ) & 3; case 4: return (line[x >> 1] >> ( ( 1 - (x & 1) ) << 2 ) ) & 15; case 8: return line[x]; + case 16: return (line[x<<1]<<8)+line[(x<<1)+1]; } return 0; } @@ -43,6 +44,7 @@ static inline void putcomponent(unsigned char *buf, int x, int bpc, int value) case 2: buf[x >> 2] |= value << ((3 - (x & 3)) << 1); break; case 4: buf[x >> 1] |= value << ((1 - (x & 1)) << 2); break; case 8: buf[x] = value; break; + case 16: buf[x<<1] = value>>8; buf[(x<<1)+1] = value; break; } } @@ -50,9 +52,9 @@ static inline int paeth(int a, int b, int c) { /* The definitions of ac and bc are correct, not a typo. */ int ac = b - c, bc = a - c, abcc = ac + bc; - int pa = ABS(ac); - int pb = ABS(bc); - int pc = ABS(abcc); + int pa = fz_absi(ac); + int pb = fz_absi(bc); + int pc = fz_absi(abcc); return pa <= pb && pa <= pc ? a : pb <= pc ? b : c; } @@ -61,9 +63,11 @@ fz_predict_tiff(fz_predict *state, unsigned char *out, unsigned char *in, int le { int left[MAXC]; int i, k; + const int mask = (1 << state->bpc)-1; for (k = 0; k < state->colors; k++) left[k] = 0; + memset(out, 0, state->stride); for (i = 0; i < state->columns; i++) { @@ -71,7 +75,7 @@ fz_predict_tiff(fz_predict *state, unsigned char *out, unsigned char *in, int le { int a = getcomponent(in, i * state->colors + k, state->bpc); int b = a + left[k]; - int c = b % (1 << state->bpc); + int c = b & mask; putcomponent(out, i * state->colors + k, state->bpc, c); left[k] = c; } |