avformat: fix decoded creation_time timestamps

Use proper ISO 8601 timestamps which also signal that they are in UTC.

This changes the format of creation_time and modification_date metadata values
from 2016-06-01 22:30:00 to 2016-01-01T22:30:00.000000Z

Fixes ticket #5673.

Signed-off-by: Marton Balint <cus@passwd.hu>

libavformat/matroskadec.c

@@ -1691,13 +1691,8 @@ static int matroska_aac_sri(int samplerate)
 
 static void matroska_metadata_creation_time(AVDictionary **metadata, int64_t date_utc)
 {
-    char buffer[32];
     /* Convert to seconds and adjust by number of seconds between 2001-01-01 and Epoch */
-    time_t creation_time = date_utc / 1000000000 + 978307200;
-    struct tm tmpbuf, *ptm = gmtime_r(&creation_time, &tmpbuf);
-    if (!ptm) return;
-    if (strftime(buffer, sizeof(buffer), "%Y-%m-%d %H:%M:%S", ptm))
-        av_dict_set(metadata, "creation_time", buffer, 0);
+    avpriv_dict_set_timestamp(metadata, "creation_time", date_utc / 1000 + 978307200000000LL);
 }
 
 static int matroska_parse_flac(AVFormatContext *s,

libavformat/mov.c

@@ -1156,17 +1156,10 @@ static int mov_read_moof(MOVContext *c, AVIOContext *pb, MOVAtom atom)
 
 static void mov_metadata_creation_time(AVDictionary **metadata, int64_t time)
 {
-    char buffer[32];
     if (time) {
-        struct tm *ptm, tmbuf;
-        time_t timet;
         if(time >= 2082844800)
             time -= 2082844800;  /* seconds between 1904-01-01 and Epoch */
-        timet = time;
-        ptm = gmtime_r(&timet, &tmbuf);
-        if (!ptm) return;
-        if (strftime(buffer, sizeof(buffer), "%Y-%m-%d %H:%M:%S", ptm))
-            av_dict_set(metadata, "creation_time", buffer, 0);
+        avpriv_dict_set_timestamp(metadata, "creation_time", time * 1000000);
     }
 }
 

libavformat/mxfdec.c

@@ -50,6 +50,7 @@
 #include "libavutil/mathematics.h"
 #include "libavcodec/bytestream.h"
 #include "libavutil/intreadwrite.h"
+#include "libavutil/parseutils.h"
 #include "libavutil/timecode.h"
 #include "avformat.h"
 #include "internal.h"
@@ -2159,7 +2160,7 @@ fail_and_free:
     return ret;
 }
 
-static int mxf_timestamp_to_str(uint64_t timestamp, char **str)
+static int64_t mxf_timestamp_to_int64(uint64_t timestamp)
 {
     struct tm time = { 0 };
     time.tm_year = (timestamp >> 48) - 1900;
@@ -2178,13 +2179,7 @@ static int mxf_timestamp_to_str(uint64_t timestamp, char **str)
     time.tm_min  = av_clip(time.tm_min,  0, 59);
     time.tm_sec  = av_clip(time.tm_sec,  0, 59);
 
-    *str = av_mallocz(32);
-    if (!*str)
-        return AVERROR(ENOMEM);
-    if (!strftime(*str, 32, "%Y-%m-%d %H:%M:%S", &time))
-        (*str)[0] = '\0';
-
-    return 0;
+    return (int64_t)av_timegm(&time) * 1000000;
 }
 
 #define SET_STR_METADATA(pb, name, str) do { \
@@ -2202,9 +2197,8 @@ static int mxf_timestamp_to_str(uint64_t timestamp, char **str)
 
 #define SET_TS_METADATA(pb, name, var, str) do { \
     var = avio_rb64(pb); \
-    if ((ret = mxf_timestamp_to_str(var, &str)) < 0) \
+    if ((ret = avpriv_dict_set_timestamp(&s->metadata, name, mxf_timestamp_to_int64(var)) < 0)) \
         return ret; \
-    av_dict_set(&s->metadata, name, str, AV_DICT_DONT_STRDUP_VAL); \
 } while (0)
 
 static int mxf_read_identification_metadata(void *arg, AVIOContext *pb, int tag, int size, UID _uid, int64_t klv_offset)

libavformat/version.h

@@ -33,7 +33,7 @@
 // Also please add any ticket numbers that you believe might be affected here
 #define LIBAVFORMAT_VERSION_MAJOR  57
 #define LIBAVFORMAT_VERSION_MINOR  48
-#define LIBAVFORMAT_VERSION_MICRO 100
+#define LIBAVFORMAT_VERSION_MICRO 101
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
                                                LIBAVFORMAT_VERSION_MINOR, \