Merge commit '708e84cda1bdbffb92847f3d6ccf6fbeb26d9948'

[ffmpeg] / libavcodec / aacdec_fixed.c

diff --git a/libavcodec/aacdec_fixed.c b/libavcodec/aacdec_fixed.c
index 27547667abc5a2ff8c55d70b39c4e346084c22cf..f6a533010f2ac3efff4addc9522a4d93d32d7259 100644 (file)
--- a/libavcodec/aacdec_fixed.c
+++ b/libavcodec/aacdec_fixed.c
@@ -181,14 +181,15 @@ static void subband_scale(int *dst, int *src, int scale, int offset, int len)
             out = (int)(((int64_t)src[i] * c) >> 32);
             dst[i] = ((int)(out+round) >> s) * ssign;
         }
-    }
-    else {
+    } else if (s > -32) {
         s = s + 32;
         round = 1U << (s-1);
         for (i=0; i<len; i++) {
             out = (int)((int64_t)((int64_t)src[i] * c + round) >> s);
-            dst[i] = out * ssign;
+            dst[i] = out * (unsigned)ssign;
         }
+    } else {
+        av_log(NULL, AV_LOG_ERROR, "Overflow in subband_scale()\n");
     }
 }
 
@@ -211,8 +212,8 @@ static void noise_scale(int *coefs, int scale, int band_energy, int len)
         for (i=0; i<len; i++) {
             coefs[i] = 0;
         }
-    } else if (s > 0) {
-        round = 1 << (s-1);
+    } else if (s >= 0) {
+        round = s ? 1 << (s-1) : 0;
         for (i=0; i<len; i++) {
             out = (int)(((int64_t)coefs[i] * c) >> 32);
             coefs[i] = ((int)(out+round) >> s) * ssign;
@@ -304,8 +305,12 @@ static av_always_inline void predict(PredictorState *ps, int *coef,
     if (output_enable) {
         int shift = 28 - pv.exp;
 
-        if (shift < 31)
-            *coef += (pv.mant + (1 << (shift - 1))) >> shift;
+        if (shift < 31) {
+            if (shift > 0) {
+                *coef += (pv.mant + (1 << (shift - 1))) >> shift;
+            } else
+                *coef += pv.mant << -shift;
+        }
     }
 
     e0 = av_int2sf(*coef, 2);
@@ -370,7 +375,9 @@ static void apply_dependent_coupling_fixed(AACContext *ac,
                     shift = (gain-1024) >> 3;
                 }
 
-                if (shift < 0) {
+                if (shift < -31) {
+                    // Nothing to do
+                } else if (shift < 0) {
                     shift = -shift;
                     round = 1 << (shift - 1);
 
@@ -387,7 +394,7 @@ static void apply_dependent_coupling_fixed(AACContext *ac,
                         for (k = offsets[i]; k < offsets[i + 1]; k++) {
                             tmp = (int)(((int64_t)src[group * 128 + k] * c + \
                                         (int64_t)0x1000000000) >> 37);
-                            dest[group * 128 + k] += tmp << shift;
+                            dest[group * 128 + k] += tmp * (1 << shift);
                         }
                     }
                 }
@@ -429,7 +436,7 @@ static void apply_independent_coupling_fixed(AACContext *ac,
     else {
       for (i = 0; i < len; i++) {
           tmp = (int)(((int64_t)src[i] * c + (int64_t)0x1000000000) >> 37);
-          dest[i] += tmp << shift;
+          dest[i] += tmp * (1 << shift);
       }
     }
 }