[FFmpeg-cvslog] alacenc: Fix missing sign_extend()

[Michael Niedermayer]

ffmpeg | branch: release/1.2 | Michael Niedermayer <michaelni at gmx.at> | Thu Jun 13 00:01:13 2013 +0200| [e22dd7fbd09d9384a08b11bafe3d1bbe0a89bf8b] | committer: Carl Eugen Hoyos

alacenc: Fix missing sign_extend()

Fixes ticket #2497

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
(cherry picked from commit 8aea2f05dc56f7e7d60767dd27ba8e846a05e8ae)

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=e22dd7fbd09d9384a08b11bafe3d1bbe0a89bf8b
---

 libavcodec/alacenc.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/alacenc.c b/libavcodec/alacenc.c
index 4ee558c..83063ab 100644
--- a/libavcodec/alacenc.c
+++ b/libavcodec/alacenc.c
@@ -274,7 +274,7 @@ static void alac_linear_predictor(AlacEncodeContext *s, int ch)
         // generate warm-up samples
         residual[0] = samples[0];
         for (i = 1; i <= lpc.lpc_order; i++)
-            residual[i] = samples[i] - samples[i-1];
+            residual[i] = sign_extend(samples[i] - samples[i-1], s->write_sample_size);
 
         // perform lpc on remaining samples
         for (i = lpc.lpc_order + 1; i < s->frame_size; i++) {