new time conversion of timestamp fields

DateTime.go

@@ -0,0 +1,21 @@
+// Copyright 2024 Martin Riedl
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package gomp4
+
+import "time"
+
+func since1904ToTime(sec int64) time.Time {
+	return time.Date(1904, time.January, 1, 0, 0, 0, 0, time.UTC).Add(time.Second * time.Duration(sec))
+}

MovieHeaderBox.go

@@ -16,6 +16,7 @@ package gomp4
 
 import (
 	"encoding/binary"
+	"time"
 )
 
 // MovieHeaderBox Movie Header Box struct
@@ -32,16 +33,16 @@ type MovieHeaderBox struct {
 	*FullBox
 	// is an integer that declares the creation time of the presentation (in seconds
 	// since midnight, Jan. 1, 1904, in UTC time)
-	CreationTimeV0 uint32
+	CreationTimeV0 time.Time
 	// is an integer that declares the creation time of the presentation (in seconds
 	// since midnight, Jan. 1, 1904, in UTC time)
-	CreationTimeV1 uint64
+	CreationTimeV1 time.Time
 	// is an integer that declares the most recent time the presentation was
 	// modified (in seconds since midnight, Jan. 1, 1904, in UTC time)
-	ModificationTimeV0 uint32
+	ModificationTimeV0 time.Time
 	// is an integer that declares the most recent time the presentation was
 	// modified (in seconds since midnight, Jan. 1, 1904, in UTC time)
-	ModificationTimeV1 uint64
+	ModificationTimeV1 time.Time
 	// is an integer that specifies the time‐scale for the entire presentation; this is the
 	// number of time units that pass in one second. For example, a time coordinate system that
 	// measures time in sixtieths of a second has a time scale of 60.
@@ -81,14 +82,14 @@ func ParseMovieHeaderBox(filePosition uint64, headerSize uint32, content []byte)
 
 	position := 4
 	if box.Version == 1 {
-		box.CreationTimeV1 = binary.BigEndian.Uint64(content[4:12])
+		box.CreationTimeV1 = since1904ToTime(int64(binary.BigEndian.Uint64(content[4:12])))
-		box.ModificationTimeV1 = binary.BigEndian.Uint64(content[12:20])
+		box.ModificationTimeV1 = since1904ToTime(int64(binary.BigEndian.Uint64(content[12:20])))
 		box.Timescale = binary.BigEndian.Uint32(content[20:24])
 		box.DurationV1 = binary.BigEndian.Uint64(content[24:32])
 		position += 28
 	} else { // version == 0
-		box.CreationTimeV0 = binary.BigEndian.Uint32(content[4:8])
+		box.CreationTimeV0 = since1904ToTime(int64(binary.BigEndian.Uint32(content[4:8])))
-		box.ModificationTimeV0 = binary.BigEndian.Uint32(content[8:12])
+		box.ModificationTimeV0 = since1904ToTime(int64(binary.BigEndian.Uint32(content[8:12])))
 		box.Timescale = binary.BigEndian.Uint32(content[12:16])
 		box.DurationV0 = binary.BigEndian.Uint32(content[16:20])
 		position += 16