fix random dithering of zero-bit mantissas
authorJustin Ruggles <justin.ruggles@gmail.com>
Sat, 15 Sep 2007 00:43:40 +0000 (00:43 +0000)
committerJustin Ruggles <justin.ruggles@gmail.com>
Sat, 15 Sep 2007 00:43:40 +0000 (00:43 +0000)
Originally committed as revision 10495 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/ac3dec.c

index 66b498b..e59b416 100644 (file)
@@ -518,7 +518,7 @@ static int get_transform_coeffs_ch(AC3DecodeContext *ctx, int ch_index, mant_gro
         tbap = bap[i];
         switch (tbap) {
             case 0:
-                coeffs[i] = ((av_random(&ctx->dith_state) & 0xFFFF) * LEVEL_MINUS_3DB) / 32768.0f;
+                coeffs[i] = ((av_random(&ctx->dith_state) & 0xFFFF) / 65535.0f) - 0.5f;
                 break;
 
             case 1: