X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fh264_parser.c;h=bca00717c4eb7f70316faf195622c2c3b286cf56;hb=94eb600f354c486fd3a9b50e052e809452673fcf;hp=3ed7d77061cae4c10fdfe01b43e85da858d3bb32;hpb=e8487d71be4dfaa3b9be519936ac74917d956d8a;p=ffmpeg

diff --git a/libavcodec/h264_parser.c b/libavcodec/h264_parser.c
index 3ed7d77061c..bca00717c4e 100644
--- a/libavcodec/h264_parser.c
+++ b/libavcodec/h264_parser.c
@@ -61,6 +61,7 @@ typedef struct H264ParseContext {
     int parse_history_count;
     int parse_last_mb;
     int64_t reference_dts;
+    int last_frame_num, last_picture_structure;
 } H264ParseContext;
 
 
@@ -528,7 +529,19 @@ static inline int parse_nal_units(AVCodecParserContext *s,
                     s->picture_structure = AV_PICTURE_STRUCTURE_TOP_FIELD;
                 else
                     s->picture_structure = AV_PICTURE_STRUCTURE_BOTTOM_FIELD;
-                s->field_order = AV_FIELD_UNKNOWN;
+                if (p->poc.frame_num == p->last_frame_num &&
+                    p->last_picture_structure != AV_PICTURE_STRUCTURE_UNKNOWN &&
+                    p->last_picture_structure != AV_PICTURE_STRUCTURE_FRAME &&
+                    p->last_picture_structure != s->picture_structure) {
+                    if (p->last_picture_structure == AV_PICTURE_STRUCTURE_TOP_FIELD)
+                        s->field_order = AV_FIELD_TT;
+                    else
+                        s->field_order = AV_FIELD_BB;
+                } else {
+                    s->field_order = AV_FIELD_UNKNOWN;
+                }
+                p->last_picture_structure = s->picture_structure;
+                p->last_frame_num = p->poc.frame_num;
             }
 
             av_freep(&nal.rbsp_buffer);
@@ -677,6 +690,7 @@ static av_cold int init(AVCodecParserContext *s)
     H264ParseContext *p = s->priv_data;
 
     p->reference_dts = AV_NOPTS_VALUE;
+    p->last_frame_num = INT_MAX;
     ff_h264dsp_init(&p->h264dsp, 8, 1);
     return 0;
 }