[libav-devel] [PATCH 2/2] flvenc: Don't copy metadata entries that are written by the muxer itself

[Martin Storsjö]

This avoids duplicate, stale metadata entries if transcoding
from one flv file to another.
---
 libavformat/flvenc.c |   20 ++++++++++++++++++++
 1 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/libavformat/flvenc.c b/libavformat/flvenc.c
index 23d19cd..d9f692f 100644
--- a/libavformat/flvenc.c
+++ b/libavformat/flvenc.c
@@ -181,6 +181,7 @@ static int flv_write_header(AVFormatContext *s)
     double framerate = 0.0;
     int64_t metadata_size_pos, data_size, metadata_count_pos;
     AVDictionaryEntry *tag = NULL;
+    AVDictionary *entries = NULL;
 
     for(i=0; i<s->nb_streams; i++){
         AVCodecContext *enc = s->streams[i]->codec;
@@ -241,6 +242,9 @@ static int flv_write_header(AVFormatContext *s)
     metadata_count = 5*!!video_enc + 5*!!audio_enc + 2; // +2 for duration and 
file size
     avio_wb32(pb, metadata_count);
 
+    av_dict_set(&entries, "duration", "", 0);
+    av_dict_set(&entries, "filesize", "", 0);
+
     put_amf_string(pb, "duration");
     flv->duration_offset= avio_tell(pb);
     put_amf_double(pb, s->duration / AV_TIME_BASE); // fill in the guessed 
duration, it'll be corrected later if incorrect
@@ -260,6 +264,12 @@ static int flv_write_header(AVFormatContext *s)
 
         put_amf_string(pb, "videocodecid");
         put_amf_double(pb, video_enc->codec_tag);
+
+        av_dict_set(&entries, "width", "", 0);
+        av_dict_set(&entries, "height", "", 0);
+        av_dict_set(&entries, "videodatarate", "", 0);
+        av_dict_set(&entries, "framerate", "", 0);
+        av_dict_set(&entries, "videocodecid", "", 0);
     }
 
     if(audio_enc){
@@ -277,14 +287,24 @@ static int flv_write_header(AVFormatContext *s)
 
         put_amf_string(pb, "audiocodecid");
         put_amf_double(pb, audio_enc->codec_tag);
+
+        av_dict_set(&entries, "audiodatarate", "", 0);
+        av_dict_set(&entries, "audiosamplerate", "", 0);
+        av_dict_set(&entries, "audiosamplesize", "", 0);
+        av_dict_set(&entries, "stereo", "", 0);
+        av_dict_set(&entries, "audiocodecid", "", 0);
     }
 
     while ((tag = av_dict_get(s->metadata, "", tag, AV_DICT_IGNORE_SUFFIX))) {
+        AVDictionaryEntry* entry = av_dict_get(entries, tag->key, NULL, 0);
+        if (entry)
+            continue; // Don't duplicate entries that we already write 
ourselves
         put_amf_string(pb, tag->key);
         avio_w8(pb, AMF_DATA_TYPE_STRING);
         put_amf_string(pb, tag->value);
         metadata_count++;
     }
+    av_dict_free(&entries);
 
     put_amf_string(pb, "filesize");
     flv->filesize_offset= avio_tell(pb);
-- 
1.7.3.1

_______________________________________________
libav-devel mailing list
libav-devel@libav.org
https://lists.libav.org/mailman/listinfo/libav-devel