[OPENJP2] change the way to compute *p_tx0, *p_tx1, *p_ty0, *p_ty1 in function

opj_get_encoding_parameters

Signed-off-by: Young_X <YangX92@hotmail.com>

diff --git a/src/lib/openjp2/pi.c b/src/lib/openjp2/pi.c
index 91642ee4eaf21c8dcffec820af5c31d9277dbf2b..4a6ed68e2b24f114a6307b22807112dc5d735084 100644 (file)
--- a/src/lib/openjp2/pi.c
+++ b/src/lib/openjp2/pi.c
@@ -748,6 +748,9 @@ static void opj_get_encoding_parameters(const opj_image_t *p_image,
     /* position in x and y of tile */
     OPJ_UINT32 p, q;
 
+    /* non-corrected (in regard to image offset) tile offset */
+    OPJ_UINT32 l_tx0, l_ty0;
+
     /* preconditions */
     assert(p_cp != 00);
     assert(p_image != 00);
@@ -763,14 +766,14 @@ static void opj_get_encoding_parameters(const opj_image_t *p_image,
     q = p_tileno / p_cp->tw;
 
     /* find extent of tile */
-    *p_tx0 = opj_int_max((OPJ_INT32)(p_cp->tx0 + p * p_cp->tdx),
-                         (OPJ_INT32)p_image->x0);
-    *p_tx1 = opj_int_min((OPJ_INT32)(p_cp->tx0 + (p + 1) * p_cp->tdx),
-                         (OPJ_INT32)p_image->x1);
-    *p_ty0 = opj_int_max((OPJ_INT32)(p_cp->ty0 + q * p_cp->tdy),
-                         (OPJ_INT32)p_image->y0);
-    *p_ty1 = opj_int_min((OPJ_INT32)(p_cp->ty0 + (q + 1) * p_cp->tdy),
-                         (OPJ_INT32)p_image->y1);
+    l_tx0 = p_cp->tx0 + p *
+            p_cp->tdx; /* can't be greater than p_image->x1 so won't overflow */
+    *p_tx0 = (OPJ_INT32)opj_uint_max(l_tx0, p_image->x0);
+    *p_tx1 = (OPJ_INT32)opj_uint_min(opj_uint_adds(l_tx0, p_cp->tdx), p_image->x1);
+    l_ty0 = p_cp->ty0 + q *
+            p_cp->tdy; /* can't be greater than p_image->y1 so won't overflow */
+    *p_ty0 = (OPJ_INT32)opj_uint_max(l_ty0, p_image->y0);
+    *p_ty1 = (OPJ_INT32)opj_uint_min(opj_uint_adds(l_ty0, p_cp->tdy), p_image->y1);
 
     /* max precision is 0 (can only grow) */
     *p_max_prec = 0;