diff --git a/src/lib/openjp2/dwt.c b/src/lib/openjp2/dwt.c index 4164ba09..824a9fc4 100644 --- a/src/lib/openjp2/dwt.c +++ b/src/lib/openjp2/dwt.c @@ -385,7 +385,8 @@ static void opj_idwt53_h_cas0(OPJ_INT32* tmp, s0n = s1n - ((d1c + d1n + 2) >> 2); tmp[i ] = s0c; - tmp[i + 1] = d1c + ((s0c + s0n) >> 1); + tmp[i + 1] = opj_int_add_no_overflow(d1c, opj_int_add_no_overflow(s0c, + s0n) >> 1); } tmp[i] = s0n; @@ -450,7 +451,7 @@ static void opj_idwt53_h_cas1(OPJ_INT32* tmp, dn = in_odd[j] - ((s1 + s2 + 2) >> 2); tmp[i ] = dc; - tmp[i + 1] = s1 + ((dn + dc) >> 1); + tmp[i + 1] = opj_int_add_no_overflow(s1, opj_int_add_no_overflow(dn, dc) >> 1); dc = dn; s1 = s2; @@ -796,7 +797,8 @@ static void opj_idwt3_v_cas0(OPJ_INT32* tmp, s1n = tiledp_col[(OPJ_SIZE_T)(j + 1) * stride]; d1n = tiledp_col[(OPJ_SIZE_T)(sn + j + 1) * stride]; - s0n = s1n - ((d1c + d1n + 2) >> 2); + s0n = opj_int_sub_no_overflow(s1n, + opj_int_add_no_overflow(opj_int_add_no_overflow(d1c, d1n), 2) >> 2); tmp[i ] = s0c; tmp[i + 1] = d1c + ((s0c + s0n) >> 1); @@ -2343,10 +2345,13 @@ static void opj_dwt_decode_partial_1(OPJ_INT32 *a, OPJ_INT32 dn, OPJ_INT32 sn, OPJ_S(0) /= 2; } else { for (i = win_l_x0; i < win_l_x1; i++) { - OPJ_D(i) -= (OPJ_SS_(i) + OPJ_SS_(i + 1) + 2) >> 2; + OPJ_D(i) = opj_int_sub_no_overflow(OPJ_D(i), + opj_int_add_no_overflow(opj_int_add_no_overflow(OPJ_SS_(i), OPJ_SS_(i + 1)), + 2) >> 2); } for (i = win_h_x0; i < win_h_x1; i++) { - OPJ_S(i) += (OPJ_DD_(i) + OPJ_DD_(i - 1)) >> 1; + OPJ_S(i) = opj_int_add_no_overflow(OPJ_S(i), + opj_int_add_no_overflow(OPJ_DD_(i), OPJ_DD_(i - 1)) >> 1); } } } @@ -2484,12 +2489,17 @@ static void opj_dwt_decode_partial_1_parallel(OPJ_INT32 *a, } else { for (i = win_l_x0; i < win_l_x1; i++) { for (off = 0; off < 4; off++) { - OPJ_D_off(i, off) -= (OPJ_SS__off(i, off) + OPJ_SS__off(i + 1, off) + 2) >> 2; + OPJ_D_off(i, off) = opj_int_sub_no_overflow( + OPJ_D_off(i, off), + opj_int_add_no_overflow( + opj_int_add_no_overflow(OPJ_SS__off(i, off), OPJ_SS__off(i + 1, off)), 2) >> 2); } } for (i = win_h_x0; i < win_h_x1; i++) { for (off = 0; off < 4; off++) { - OPJ_S_off(i, off) += (OPJ_DD__off(i, off) + OPJ_DD__off(i - 1, off)) >> 1; + OPJ_S_off(i, off) = opj_int_add_no_overflow( + OPJ_S_off(i, off), + opj_int_add_no_overflow(OPJ_DD__off(i, off), OPJ_DD__off(i - 1, off)) >> 1); } } } diff --git a/src/lib/openjp2/opj_intmath.h b/src/lib/openjp2/opj_intmath.h index afe69d90..f8cc6139 100644 --- a/src/lib/openjp2/opj_intmath.h +++ b/src/lib/openjp2/opj_intmath.h @@ -276,6 +276,44 @@ static INLINE OPJ_INT32 opj_int_fix_mul_t1(OPJ_INT32 a, OPJ_INT32 b) return (OPJ_INT32)(temp >> (13 + 11 - T1_NMSEDEC_FRACBITS)) ; } +/** +Addtion two signed integers with a wrap-around behaviour. +Assumes complement-to-two signed integers. +@param a +@param b +@return Returns a + b +*/ +static INLINE OPJ_INT32 opj_int_add_no_overflow(OPJ_INT32 a, OPJ_INT32 b) +{ + void* pa = &a; + void* pb = &b; + OPJ_UINT32* upa = (OPJ_UINT32*)pa; + OPJ_UINT32* upb = (OPJ_UINT32*)pb; + OPJ_UINT32 ures = *upa + *upb; + void* pures = &ures; + OPJ_INT32* ipres = (OPJ_INT32*)pures; + return *ipres; +} + +/** +Subtract two signed integers with a wrap-around behaviour. +Assumes complement-to-two signed integers. +@param a +@param b +@return Returns a - b +*/ +static INLINE OPJ_INT32 opj_int_sub_no_overflow(OPJ_INT32 a, OPJ_INT32 b) +{ + void* pa = &a; + void* pb = &b; + OPJ_UINT32* upa = (OPJ_UINT32*)pa; + OPJ_UINT32* upb = (OPJ_UINT32*)pb; + OPJ_UINT32 ures = *upa - *upb; + void* pures = &ures; + OPJ_INT32* ipres = (OPJ_INT32*)pures; + return *ipres; +} + /* ----------------------------------------------------------------------- */ /*@}*/