*
* @param a first value
* @param b value doubled and added to a
- * @return sum with signed saturation
+ * @return sum sat(a + sat(2*b)) with signed saturation
*/
static av_always_inline int av_sat_dadd32_c(int a, int b)
{
return av_sat_add32(a, av_sat_add32(b, b));
}
+/**
+ * Subtract two signed 32-bit values with saturation.
+ *
+ * @param a one value
+ * @param b another value
+ * @return difference with signed saturation
+ */
+static av_always_inline int av_sat_sub32_c(int a, int b)
+{
+ return av_clipl_int32((int64_t)a - b);
+}
+
+/**
+ * Subtract a doubled value from another value with saturation at both stages.
+ *
+ * @param a first value
+ * @param b value doubled and subtracted from a
+ * @return difference sat(a - sat(2*b)) with signed saturation
+ */
+static av_always_inline int av_sat_dsub32_c(int a, int b)
+{
+ return av_sat_sub32(a, av_sat_add32(b, b));
+}
+
/**
* Clip a float value into the amin-amax range.
* @param a value to clip
#ifndef av_sat_dadd32
# define av_sat_dadd32 av_sat_dadd32_c
#endif
+#ifndef av_sat_sub32
+# define av_sat_sub32 av_sat_sub32_c
+#endif
+#ifndef av_sat_dsub32
+# define av_sat_dsub32 av_sat_dsub32_c
+#endif
#ifndef av_clipf
# define av_clipf av_clipf_c
#endif