diff options
Diffstat (limited to 'pixman/pixman-filter.c')
| -rw-r--r-- | pixman/pixman-filter.c | 31 |
1 files changed, 22 insertions, 9 deletions
diff --git a/pixman/pixman-filter.c b/pixman/pixman-filter.c index 5f3b752..fa94532 100644 --- a/pixman/pixman-filter.c +++ b/pixman/pixman-filter.c @@ -237,11 +237,14 @@ create_1d_filter (int width, pixman_kernel_t sample, double scale, int n_phases, - pixman_fixed_t *p) + pixman_fixed_t *pstart, + pixman_fixed_t *pend + ) { + pixman_fixed_t *p = pstart; double step; int i; - + if(width <= 0) return; step = 1.0 / n_phases; for (i = 0; i < n_phases; ++i) @@ -258,7 +261,7 @@ create_1d_filter (int width, x1 = ceil (frac - width / 2.0 - 0.5); x2 = x1 + width; - + assert( p >= pstart && p + (x2 - x1) <= pend ); /* assert validity of the following loop */ total = 0; for (x = x1; x < x2; ++x) { @@ -287,8 +290,10 @@ create_1d_filter (int width, /* Normalize, with error diffusion */ p -= width; - total = 65536.0 / total; - new_total = 0; + assert(p >= pstart && p + (x2 - x1) <= pend); /* assert validity of the following loop */ + + total = 65536.0 / total; + new_total = 0; e = 0.0; for (x = x1; x < x2; ++x) { @@ -304,6 +309,8 @@ create_1d_filter (int width, * at the first sample, since that is the only one that * hasn't had any error diffused into it. */ + + assert(p - width >= pstart && p - width < pend); /* assert... */ *(p - width) += pixman_fixed_1 - new_total; } } @@ -465,10 +472,16 @@ pixman_filter_create_separable_convolution (int *n_values, params[2] = pixman_int_to_fixed (subsample_bits_x); params[3] = pixman_int_to_fixed (subsample_bits_y); - create_1d_filter (width, reconstruct_x, sample_x, sx, subsample_x, - params + 4); - create_1d_filter (height, reconstruct_y, sample_y, sy, subsample_y, - params + 4 + width * subsample_x); + { + pixman_fixed_t + *xparams = params+4, + *yparams = xparams + width*subsample_x, + *endparams = params + *n_values; + create_1d_filter(width, reconstruct_x, sample_x, sx, subsample_x, + xparams, yparams); + create_1d_filter(height, reconstruct_y, sample_y, sy, subsample_y, + yparams, endparams); + } #ifdef PIXMAN_GNUPLOT gnuplot_filter(width, subsample_x, params + 4); |