AC3 encoding volume fix, by Justin Ruggles jruggle earthlink net.

Originally committed as revision 5281 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/ac3enc.c

@@ -1377,7 +1377,7 @@ static int AC3_encode_frame(AVCodecContext *avctx,
             v = 14 - log2_tab(input_samples, N);
             if (v < 0)
                 v = 0;
-            exp_samples[i][ch] = v - 8;
+            exp_samples[i][ch] = v - 9;
             lshift_tab(input_samples, N, v);
 
             /* do the MDCT */

tests/ffmpeg.regression.ref

@@ -150,7 +150,7 @@ stddev: 10.99 PSNR:27.30 bytes:7602176
 6956f2c5185c4edbae648c614992a14b *./data/out.wav
 stddev:9330.70 PSNR:16.92 bytes:527360
 stddev:4396.13 PSNR:23.46 bytes:526336
-4292b4f8e930e386e9c00799197615e5 *./data/a-ac3.rm
+aefe11ab5067621a1c674859d6413891 *./data/a-ac3.rm
 98203 ./data/a-ac3.rm
 9e6e66847a568ef4f1f229b0939d2aae *./data/a-g726.wav
 24268 ./data/a-g726.wav

tests/libav.regression.ref

@@ -5,7 +5,7 @@ ffmpeg regression test
 6f4dca897d9a009009798e434fe5f651 *./data/b-libav.asf
  342967 ./data/b-libav.asf
 ./data/b-libav.asf CRC=0x41af1ed9
-4509d6cc5523484d4557b2e5f06f5157 *./data/b-libav.rm
+5275686385346789108ec4fdf06ecef8 *./data/b-libav.rm
 360269 ./data/b-libav.rm
 90784a1b9589095f20fc6bcc0cc23cc4 *./data/b-libav.mpg
  387072 ./data/b-libav.mpg

tests/rotozoom.regression.ref

@@ -150,7 +150,7 @@ stddev:  3.44 PSNR:37.38 bytes:7602176
 6956f2c5185c4edbae648c614992a14b *./data/out.wav
 stddev:9330.70 PSNR:16.92 bytes:527360
 stddev:4396.13 PSNR:23.46 bytes:526336
-4292b4f8e930e386e9c00799197615e5 *./data/a-ac3.rm
+aefe11ab5067621a1c674859d6413891 *./data/a-ac3.rm
 98203 ./data/a-ac3.rm
 9e6e66847a568ef4f1f229b0939d2aae *./data/a-g726.wav
 24268 ./data/a-g726.wav