right shift the values by 8 in GAQ remap "B" table. data now fits in int8_t.

Originally committed as revision 14958 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/ac3dec_data.c

@@ -87,18 +87,19 @@ const int16_t ff_eac3_gaq_remap_2_4_a[9][2] = {
 /**
  * Table E3.6, Gk=2 & Gk=4, B
  * Large mantissa inverse quantization, negative mantissa remapping offsets
+ * Table values from the spec are right-shifted by 8 to simplify calculations.
  * ff_eac3_gaq_remap_3_4_b[hebap-8][Gk=2,4]
  */
-const int16_t ff_eac3_gaq_remap_2_4_b[9][2] = {
+const int8_t ff_eac3_gaq_remap_2_4_b[9][2] = {
-    {  -5461, -1170},
+    { -22,  -5 },
-    { -11703, -4915},
+    { -46, -20 },
-    { -14199, -6606},
+    { -56, -26 },
-    { -15327, -7412},
+    { -60, -29 },
-    { -15864, -7805},
+    { -62, -31 },
-    { -16126, -7999},
+    { -63, -32 },
-    { -16255, -8096},
+    { -64, -32 },
-    { -16320, -8144},
+    { -64, -32 },
-    { -16352, -8168}
+    { -64, -32 },
 };
 
 static const int16_t vq_hebap1[4][6] = {

libavcodec/ac3dec_data.h

@@ -29,7 +29,7 @@ extern const uint8_t ff_eac3_hebap_tab[64];
 extern const uint8_t ff_eac3_bits_vs_hebap[20];
 extern const int16_t ff_eac3_gaq_remap_1[12];
 extern const int16_t ff_eac3_gaq_remap_2_4_a[9][2];
-extern const int16_t ff_eac3_gaq_remap_2_4_b[9][2];
+extern const int8_t  ff_eac3_gaq_remap_2_4_b[9][2];
 
 extern const int16_t (*ff_eac3_vq_hebap[8])[6];
 extern const uint8_t ff_eac3_frm_expstr[32][6];