From: Michael Niedermayer <michaelni@gmx.at>
Date: Tue, 23 Sep 2008 23:16:48 +0000 (+0000)
Subject: Merge the 2 lpc loops.
X-Git-Tag: v0.5~2436
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=645a6be1e763441ee38ecc1b55b8d0408ef8f04f;p=platform%2Fupstream%2Flibav.git

Merge the 2 lpc loops.
This changes the output by (stddev:    0.21 PSNR:109.51, file:ddinterview28.ra),
the changes are due to float rounding inaccuracies and do not happen if doubles
are used.

Originally committed as revision 15394 to svn://svn.ffmpeg.org/ffmpeg/trunk
---

diff --git a/libavcodec/ra288.c b/libavcodec/ra288.c
index c56718a..f7e1af5 100644
--- a/libavcodec/ra288.c
+++ b/libavcodec/ra288.c
@@ -103,16 +103,14 @@ static void decode(RA288Context *ractx, float gain, int cb_coef)
     gain_block[9] = 10 * log10(sum) - 32;
 
     for (i=0; i < 5; i++) {
-        block[i] = 0;
+        block[i] = buffer[i];
         for (j=0; j < 36; j++)
             block[i] -= block[i-1-j]*ractx->sp_lpc[j];
-        for (j=0; j < i; j++)
-            buffer[i] -= buffer[i-1-j]*ractx->sp_lpc[j];
     }
 
     /* output */
     for (i=0; i < 5; i++)
-        block[i] = av_clipf(block[i] + buffer[i], -4095, 4095);
+        block[i] = av_clipf(block[i], -4095, 4095);
 }
 
 static void convolve(float *tgt, const float *src, int len, int n)