[FFmpeg-cvslog] indeo5: Fix null pointer dereferences of ref_mb

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Thu Dec 29 02:34:43 2011 +0100| [f41a6c8f3aeb51332bb359038cb504d3fb562a52] | committer: Michael Niedermayer

indeo5: Fix null pointer dereferences of ref_mb

Reviewed-by: Derek Buitenhuis <derek.buitenhuis at gmail.com>
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=f41a6c8f3aeb51332bb359038cb504d3fb562a52
---

 libavcodec/indeo5.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/libavcodec/indeo5.c b/libavcodec/indeo5.c
index cd6e689..fc534dd 100644
--- a/libavcodec/indeo5.c
+++ b/libavcodec/indeo5.c
@@ -482,7 +482,7 @@ static int decode_mb_info(IVI5DecContext *ctx, IVIBandDesc *band,
                 }
 
                 mb->mv_x = mb->mv_y = 0; /* no motion vector coded */
-                if (band->inherit_mv){
+                if (band->inherit_mv && ref_mb){
                     /* motion vector inheritance */
                     if (mv_scale) {
                         mb->mv_x = ivi_scale_mv(ref_mb->mv_x, mv_scale);
@@ -493,7 +493,7 @@ static int decode_mb_info(IVI5DecContext *ctx, IVIBandDesc *band,
                     }
                 }
             } else {
-                if (band->inherit_mv) {
+                if (band->inherit_mv && ref_mb) {
                     mb->type = ref_mb->type; /* copy mb_type from corresponding reference mb */
                 } else if (ctx->frame_type == FRAMETYPE_INTRA) {
                     mb->type = 0; /* mb_type is always INTRA for intra-frames */
@@ -519,7 +519,7 @@ static int decode_mb_info(IVI5DecContext *ctx, IVIBandDesc *band,
                 if (!mb->type) {
                     mb->mv_x = mb->mv_y = 0; /* there is no motion vector in intra-macroblocks */
                 } else {
-                    if (band->inherit_mv){
+                    if (band->inherit_mv && ref_mb){
                         /* motion vector inheritance */
                         if (mv_scale) {
                             mb->mv_x = ivi_scale_mv(ref_mb->mv_x, mv_scale);