mpeg4videodec: Fix division by zero in mpeg4_decode_sprite_trajectory()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2011-12-24 20:27:54 +01:00
parent 43abef9fde
commit fc5c49ab32

View File

@ -160,7 +160,7 @@ static inline int mpeg4_is_resync(MpegEncContext *s){
return 0;
}
static void mpeg4_decode_sprite_trajectory(MpegEncContext * s, GetBitContext *gb)
static int mpeg4_decode_sprite_trajectory(MpegEncContext * s, GetBitContext *gb)
{
int i;
int a= 2<<s->sprite_warping_accuracy;
@ -176,6 +176,9 @@ static void mpeg4_decode_sprite_trajectory(MpegEncContext * s, GetBitContext *gb
int h= s->height;
int min_ab;
if(w<=0 || h<=0)
return -1;
for(i=0; i<s->num_sprite_warping_points; i++){
int length;
int x=0, y=0;
@ -348,6 +351,7 @@ static void mpeg4_decode_sprite_trajectory(MpegEncContext * s, GetBitContext *gb
}
s->real_sprite_warping_points= s->num_sprite_warping_points;
}
return 0;
}
/**
@ -411,7 +415,8 @@ int mpeg4_decode_video_packet_header(MpegEncContext *s)
skip_bits(&s->gb, 3); /* intra dc vlc threshold */
//FIXME don't just ignore everything
if(s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
mpeg4_decode_sprite_trajectory(s, &s->gb);
if(mpeg4_decode_sprite_trajectory(s, &s->gb) < 0)
return -1;
av_log(s->avctx, AV_LOG_ERROR, "untested\n");
}
@ -2051,7 +2056,8 @@ static int decode_vop_header(MpegEncContext *s, GetBitContext *gb){
}
if(s->pict_type == AV_PICTURE_TYPE_S && (s->vol_sprite_usage==STATIC_SPRITE || s->vol_sprite_usage==GMC_SPRITE)){
mpeg4_decode_sprite_trajectory(s, gb);
if(mpeg4_decode_sprite_trajectory(s, gb) < 0)
return -1;
if(s->sprite_brightness_change) av_log(s->avctx, AV_LOG_ERROR, "sprite_brightness_change not supported\n");
if(s->vol_sprite_usage==STATIC_SPRITE) av_log(s->avctx, AV_LOG_ERROR, "static sprite not supported\n");
}