vf_unsharp: fix out-of-buffer read

In apply_unsharp(), when y is >= height, prevent out-of-buffer reading
from src, read from the last buffer line in src2 instead.

The check was implemented in the original unsharp libmpcodecs code and
lost in the port.

This also fixes output discrepancy between the two filters.
This commit is contained in:
Stefano Sabatini 2011-08-12 08:42:35 +02:00
parent 6e89bdfecf
commit 63b61d55f9

View File

@ -73,6 +73,7 @@ static void apply_unsharp( uint8_t *dst, int dst_stride,
int32_t res;
int x, y, z;
const uint8_t *src2;
if (!fp->amount) {
if (dst_stride == src_stride)
@ -87,9 +88,12 @@ static void apply_unsharp( uint8_t *dst, int dst_stride,
memset(sc[y], 0, sizeof(sc[y][0]) * (width + 2 * fp->steps_x));
for (y = -fp->steps_y; y < height + fp->steps_y; y++) {
if (y < height)
src2 = src;
memset(sr, 0, sizeof(sr[0]) * (2 * fp->steps_x - 1));
for (x = -fp->steps_x; x < width + fp->steps_x; x++) {
tmp1 = x <= 0 ? src[0] : x >= width ? src[width-1] : src[x];
tmp1 = x <= 0 ? src2[0] : x >= width ? src2[width-1] : src2[x];
for (z = 0; z < fp->steps_x * 2; z += 2) {
tmp2 = sr[z + 0] + tmp1; sr[z + 0] = tmp1;
tmp1 = sr[z + 1] + tmp2; sr[z + 1] = tmp2;