new media box and media header box

Box.go

@@ -32,6 +32,10 @@ const (
 	BoxTypeTrackBox = "trak"
 	// BoxTypeTrackHeaderBox Track Header Box
 	BoxTypeTrackHeaderBox = "tkhd"
+	// BoxTypeMediaBox Media Box
+	BoxTypeMediaBox = "mdia"
+	// BoxTypeMediaHeaderBox Media Header Box
+	BoxTypeMediaHeaderBox = "mdhd"
 	// BoxTypeMovieFragment Movie Fragment Box
 	BoxTypeMovieFragment = "moof"
 	// BoxTypeMovieFragmentHeader Movie Fragment Header Box

MediaBox.go

@@ -0,0 +1,41 @@
+// 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
+
+// MediaBox media box struct
+//
+// 8.4.1 Media Box
+//
+// Box Type: ‘mdia’
+// Container: Track Box (‘trak’)
+// Mandatory: Yes
+// Quantity: Exactly one
+//
+// The media declaration container contains all the objects that declare information about the media data
+// within a track.
+type MediaBox struct {
+	*Box
+	ChildBoxes []interface{}
+}
+
+// ParseMediaBox creates a new media box struct based on bytes
+func ParseMediaBox(filePosition uint64, headerSize uint32, content []byte) (*MediaBox, error) {
+	box := &MediaBox{Box: &Box{filePosition, headerSize}}
+
+	// parse child boxes
+	var err error
+	box.ChildBoxes, err = box.parseChildBoxes(filePosition, content)
+	return box, err
+}

MediaHeaderBox.go

@@ -0,0 +1,85 @@
+// 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 (
+	"encoding/binary"
+	"time"
+)
+
+// MediaHeaderBox media header box struct
+//
+// 8.4.2 Media Header Box
+//
+// Box Type: ‘mdhd’
+// Container: Media Box (‘mdia’)
+// Mandatory: Yes
+// Quantity: Exactly one
+//
+// The media header declares overall information that is media‐independent, and relevant to
+// characteristics of the media in a track.
+type MediaHeaderBox struct {
+	*FullBox
+	// is an integer that declares the creation time of the media in this track (in
+	// seconds since midnight, Jan. 1, 1904, in UTC time).
+	CreationTimeV0 time.Time
+	// is an integer that declares the creation time of the media in this track (in
+	// seconds since midnight, Jan. 1, 1904, in UTC time).
+	CreationTimeV1 time.Time
+	// is an integer that declares the most recent time the media in this track was
+	// modified (in seconds since midnight, Jan. 1, 1904, in UTC time).
+	ModificationTimeV0 time.Time
+	// is an integer that declares the most recent time the media in this track was
+	// modified (in seconds since midnight, Jan. 1, 1904, in UTC time).
+	ModificationTimeV1 time.Time
+	// is an integer that specifies the time‐scale for this media; 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.
+	Timescale uint32
+	// is an integer that declares the duration of this media (in the scale of the timescale). If the
+	// duration cannot be determined then duration is set to all 1s.
+	DurationV0 uint32
+	// is an integer that declares the duration of this media (in the scale of the timescale). If the
+	// duration cannot be determined then duration is set to all 1s.
+	DurationV1 uint64
+
+	// TODO: parse language language
+}
+
+// ParseMediaHeaderBox creates a new Track Header Box struct
+func ParseMediaHeaderBox(filePosition uint64, headerSize uint32, content []byte) *MediaHeaderBox {
+	box := &MediaHeaderBox{
+		FullBox: newFullBox(&Box{filePosition, headerSize}, content[0:4]),
+	}
+
+	position := 4
+	if box.Version == 1 {
+		box.CreationTimeV1 = since1904ToTime(int64(binary.BigEndian.Uint64(content[position : position+8])))
+		box.ModificationTimeV1 = since1904ToTime(int64(binary.BigEndian.Uint64(content[position+8 : position+16])))
+		box.Timescale = binary.BigEndian.Uint32(content[position+16 : position+20])
+		box.DurationV1 = binary.BigEndian.Uint64(content[position+20 : position+28])
+		position += 28
+	} else { // version == 0
+		box.CreationTimeV0 = since1904ToTime(int64(binary.BigEndian.Uint32(content[position : position+4])))
+		box.ModificationTimeV0 = since1904ToTime(int64(binary.BigEndian.Uint32(content[position+4 : position+8])))
+		box.Timescale = binary.BigEndian.Uint32(content[position+8 : position+12])
+		box.DurationV0 = binary.BigEndian.Uint32(content[position+12 : position+16])
+		position += 16
+	}
+
+	// TODO: parse language language
+
+	return box
+}

Parser.go

@@ -116,6 +116,10 @@ func parseNextBox(reader io.Reader, filePosition uint64) (box interface{}, endPo
 		box, err = ParseTrackBox(filePosition, boxHeaderSize, boxContentBytes)
 	case BoxTypeTrackHeaderBox:
 		box = ParseTrackHeaderBox(filePosition, boxHeaderSize, boxContentBytes)
+	case BoxTypeMediaBox:
+		box, err = ParseMediaBox(filePosition, boxHeaderSize, boxContentBytes)
+	case BoxTypeMediaHeaderBox:
+		box = ParseMediaHeaderBox(filePosition, boxHeaderSize, boxContentBytes)
 	case BoxTypeMovieFragment:
 		box, err = ParseMovieFragmentBox(filePosition, boxHeaderSize, boxContentBytes)
 	case BoxTypeMovieFragmentHeader:

README.md

@@ -27,8 +27,8 @@ Implementation progress
 | 8.3.2 Track Header Box                             | tkhd           |   100% |
 | 8.3.3 Track Reference Box                          | tref           |      - |
 | 8.3.4 Track Group Box                              | trgr           |      - |
-| 8.4.1 Media Box                                    | mdia           |      - |
-| 8.4.2 Media Header Box                             | mdhd           |      - |
+| 8.4.1 Media Box                                    | mdia           |   100% |
+| 8.4.2 Media Header Box                             | mdhd           |    80% |
 | 8.4.3 Handler Reference Box                        | hdlr           |      - |
 | 8.4.4 Media Information Box                        | minf           |      - |
 | 8.4.5.2 Null Media Header Box                      | nmhd           |      - |