[FFmpeg-devel] [PATCH 2/2] avcodec/mpeg12dec: avoid adding PANSCAN side data unless present

[Aman Gupta]

From: Aman Gupta <aman at tmm1.net>

---
 libavcodec/mpeg12dec.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c
index 82bb1286ff..2c96dfa638 100644
--- a/libavcodec/mpeg12dec.c
+++ b/libavcodec/mpeg12dec.c
@@ -54,6 +54,7 @@ typedef struct Mpeg1Context {
     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
     int repeat_field;           /* true if we must repeat the field */
     AVPanScan pan_scan;         /* some temporary storage for the panscan */
+    int has_pan_scan;
     AVStereo3D stereo3d;
     int has_stereo3d;
     uint8_t *a53_caption;
@@ -1458,6 +1459,7 @@ static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
 
     s1->pan_scan.width  = 16 * w;
     s1->pan_scan.height = 16 * h;
+    s1->has_pan_scan = 1;
 
     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
@@ -1489,6 +1491,8 @@ static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
         skip_bits(&s->gb, 1); // marker
     }
 
+    s1->has_pan_scan = 1;
+
     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
         av_log(s->avctx, AV_LOG_DEBUG,
                "pde (%"PRId16",%"PRId16") (%"PRId16",%"PRId16") (%"PRId16",%"PRId16")\n",
@@ -1621,12 +1625,16 @@ static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
             }
         }
 
-        pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
-                                          AV_FRAME_DATA_PANSCAN,
-                                          sizeof(s1->pan_scan));
-        if (!pan_scan)
-            return AVERROR(ENOMEM);
-        memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
+        if (s1->has_pan_scan) {
+            pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
+                                            AV_FRAME_DATA_PANSCAN,
+                                            sizeof(s1->pan_scan));
+            if (!pan_scan)
+                return AVERROR(ENOMEM);
+
+            memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
+            s1->has_pan_scan = 0;
+        }
 
         if (s1->a53_caption) {
             AVFrameSideData *sd = av_frame_new_side_data(
-- 
2.14.2