caf muxer: write metadata

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Changelog

@@ -17,6 +17,7 @@ version <next>:
 - support for building DLLs using MSVC
 - LVF demuxer
 - ffescape tool
+- metadata (info chunk) support in CAF muxer
 
 
 version 1.0:

libavformat/cafenc.c

@@ -25,6 +25,7 @@
 #include "isom.h"
 #include "avio_internal.h"
 #include "libavutil/intfloat.h"
+#include "libavutil/dict.h"
 
 typedef struct {
     int64_t data;
@@ -102,7 +103,9 @@ static int caf_write_header(AVFormatContext *s)
     AVIOContext *pb = s->pb;
     AVCodecContext *enc = s->streams[0]->codec;
     CAFContext *caf = s->priv_data;
+    AVDictionaryEntry *t = NULL;
     unsigned int codec_tag = ff_codec_get_tag(ff_codec_caf_tags, enc->codec_id);
+    int64_t chunk_size = 0;
 
     switch (enc->codec_id) {
     case AV_CODEC_ID_AAC:
@@ -180,6 +183,20 @@ static int caf_write_header(AVFormatContext *s)
         avio_write(pb, enc->extradata, enc->extradata_size);
     }
 
+    if (av_dict_count(s->metadata)) {
+        ffio_wfourcc(pb, "info"); //< Information chunk
+        while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
+            chunk_size += strlen(t->key) + strlen(t->value) + 2;
+        }
+        avio_wb64(pb, chunk_size + 4);
+        avio_wb32(pb, av_dict_count(s->metadata));
+        t = NULL;
+        while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
+            avio_put_str(pb, t->key);
+            avio_put_str(pb, t->value);
+        }
+    }
+
     ffio_wfourcc(pb, "data"); //< Audio Data chunk
     caf->data = avio_tell(pb);
     avio_wb64(pb, -1);        //< mChunkSize

libavformat/version.h

@@ -30,7 +30,7 @@
 #include "libavutil/avutil.h"
 
 #define LIBAVFORMAT_VERSION_MAJOR 54
-#define LIBAVFORMAT_VERSION_MINOR 34
+#define LIBAVFORMAT_VERSION_MINOR 35
 #define LIBAVFORMAT_VERSION_MICRO 100
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \

tests/ref/lavf/caf

-71e1abdfc59613fe05fca2939f02e02d *./tests/data/lavf/lavf.caf
-90204 ./tests/data/lavf/lavf.caf
+6c97bfc8e455d5fb8b3b45806857a953 *./tests/data/lavf/lavf.caf
+90235 ./tests/data/lavf/lavf.caf
 ./tests/data/lavf/lavf.caf CRC=0xf1ae5536