public static float CalculateTimeScale(MovieMetadataBox moovBox, TrackBox trackBox)
{
MovieHeaderBox headerBox = moovBox.MovieHeaderBox;
ulong moovDuration = headerBox.Duration;
uint moovTimeScale = headerBox.TimeScale;
MediaHeaderBox mdhdBox = trackBox.MediaBox.MediaHeaderBox;
ulong mediaDuration = mdhdBox.Duration;
float mediaTimeScale = mdhdBox.TimeScale;
// Note that time scales may differ between moov and each media (because sampling rate can differ?)
moovDuration = moovDuration / moovTimeScale;
mediaDuration = (ulong)(mediaDuration / mediaTimeScale);
long diff = Math.Abs((long)moovDuration - (long)mediaDuration);
if ((diff * diff) > (long)((moovDuration * moovDuration) / 100)) // must be within 1%
{
throw new Exception("Media Box Header inconsistent with Track Header");
}
// scale to 10,000,000 ticks per second
mediaTimeScale /= TimeSpan.FromSeconds(1.0).Ticks;
if (mediaTimeScale == 0)
{
throw new Exception("MP4VideoTrack: media time scale is zero");
}
return(mediaTimeScale);
}
public static float CalculateTimeScale(MovieMetadataBox moovBox, TrackBox trackBox)
{
MovieHeaderBox headerBox = moovBox.MovieHeaderBox;
ulong moovDuration = headerBox.Duration;
uint moovTimeScale = headerBox.TimeScale;
MediaHeaderBox mdhdBox = trackBox.MediaBox.MediaHeaderBox;
ulong mediaDuration = mdhdBox.Duration;
float mediaTimeScale = mdhdBox.TimeScale;
// Note that time scales may differ between moov and each media (because sampling rate can differ?)
moovDuration = moovDuration / moovTimeScale;
mediaDuration = (ulong)(mediaDuration / mediaTimeScale);
long diff = Math.Abs((long)moovDuration - (long)mediaDuration);
if ((diff * diff) > (long)((moovDuration * moovDuration) / 100)) // must be within 1%
throw new Exception("Media Box Header inconsistent with Track Header");
// scale to 10,000,000 ticks per second
mediaTimeScale /= TimeSpan.FromSeconds(1.0).Ticks;
if (mediaTimeScale == 0)
throw new Exception("MP4VideoTrack: media time scale is zero");
return mediaTimeScale;
}
public MovieMetadataBox(List <IsochronousTrackInfo> trackInfos, float rate, float volume, uint[] matrix)
: base(BoxTypes.Movie)
{
// initialize movie duration to zero, then increment it for every slice that is written
ulong scaledDuration = (ulong)TimeArithmetic.ConvertToTimeScale(trackInfos[0].MovieTimeScale, trackInfos[0].MovieDurationIn100NanoSecs);
MovieHeaderBox = new MovieHeaderBox(trackInfos[0].MovieTimeScale, scaledDuration, rate, volume, matrix);
this.Size += MovieHeaderBox.Size;
TrackBoxes = new TrackBox[trackInfos.Count]; // may have more than 2 tracks
// MovieExtendsBox should only exist if this is a fragment
if (trackInfos[0].IsFragment)
{
MovieExtendsBox = new MovieExtendsBox(this, trackInfos);
this.Size += MovieExtendsBox.Size;
}
}
/// <summary>
/// FinalizeStream
/// 1. Write out ftyp
/// 2. Finalize stbl box in each trak box (call mmb.FinalizeBox)
/// 3. Calculate size of ftyp + moov + header of mdat boxes
/// 4. Fix fileoffsets in stbl chunk boxes (NOTE: interleaving means we should have more than one chunk)
/// 5. Write out all of moov box
/// 6. Create and write out mdat header only, with correct byte count
/// 7. Read from mdat sample file and write to destination mdat
/// </summary>
public override void FinalizeStream()
{
// step 0
// flush all remaining slices
if (this.CachingEnabled)
{
foreach (GenericMediaTrack track in this.MediaTracks)
{
if ((track.SampleStreamLocations != null) && (track.SampleStreamLocations.Count > 0))
{
ulong _currMDatOffset = CurrMDatOffset;
track.TrackFormat.PrepareSampleWriting(track.SampleStreamLocations, ref _currMDatOffset);
CurrMDatOffset = _currMDatOffset;
this.WriteSamples(track.SampleStreamLocations.Cast <Slice>(), track.Codec.CodecType);
}
}
}
// set duration of movie (must be set to duration of longest track)
TrackBox trkBox = this.mmb.TrackBoxes.FirstOrDefault(box => box.MediaBox.HandlerReferenceBox.HandlerType.Equals("vide"));
decimal vDuration;
if (trkBox == null)
{
vDuration = 0;
}
else
{
vDuration = (decimal)trkBox.MediaBox.MediaHeaderBox.Duration / trkBox.MediaBox.MediaHeaderBox.TimeScale;
}
trkBox = this.mmb.TrackBoxes.FirstOrDefault(box => box.MediaBox.HandlerReferenceBox.HandlerType.Equals("soun"));
decimal aDuration;
if (trkBox == null)
{
aDuration = 0;
}
else
{
aDuration = (decimal)trkBox.MediaBox.MediaHeaderBox.Duration / trkBox.MediaBox.MediaHeaderBox.TimeScale;
}
if (vDuration < aDuration)
{
this.mmb.MovieHeaderBox.Duration = (ulong)(aDuration * this.mmb.MovieHeaderBox.TimeScale);
}
else
{
this.mmb.MovieHeaderBox.Duration = (ulong)(vDuration * this.mmb.MovieHeaderBox.TimeScale);
}
// step 1
this.ftb.Write(m_writer);
// step 2
this.mmb.FinalizeBox();
// step 3
int headerSize = (int)(this.ftb.Size + this.mmb.Size);
// step 4
foreach (TrackBox tbox in this.mmb.TrackBoxes)
{
tbox.MediaBox.MediaInformationBox.SampleTableBox.ChunkOffSetBox.Fixup(headerSize);
}
// step 5
this.mmb.Write(m_writer);
// step 6
this.MediaDataBoxList = new List <MediaDataBox>(); // there is only one mdat for non-fragmented streams.
MediaDataBox mdat = new MediaDataBox();
// because the mdat is the last box in the file, we can set its size to 0
// if mdat is too large, set its size filed to zero:
// this gets WMP to work, but VLC and QT doesn't like it.
mdat.Size += (ulong)tempMdat.Length;
if (mdat.Size > uint.MaxValue)
{
mdat.Size = 0UL; // += (ulong)tempMdat.Length;
}
this.MediaDataBoxList.Add(mdat);
// step 7
tempMdat.Position = 0L;
mdat.Write(m_writer, tempMdat);
// close file
Close();
}
public MediaBox(TrackBox inParent)
: base(BoxTypes.Media)
{
parent = inParent;
}
public override void Read(BoxReader reader)
{
long testpos = reader.BaseStream.Position;
using (new SizeChecker(this, reader)) {
base.Read(reader);
MovieHeaderBox.Read(reader);
// Don't assume any order in the boxes within this after the header.
// (The order depends on the brand.)
int tbcount = 0;
TrackBox[] tmpTBs = new TrackBox[10];
while (reader.BaseStream.Position < (long)(this.Size + this.Offset))
{
long pos = reader.BaseStream.Position;
Box tmpBox = new Box(BoxTypes.Any);
tmpBox.Read(reader);
reader.BaseStream.Position = pos;
if (tmpBox.Type == BoxTypes.Track)
{
TrackBox tb = new TrackBox(this, MovieHeaderBox.TimeScale);
tb.Read(reader);
tmpTBs[tbcount] = tb;
tbcount++;
}
else if (tmpBox.Type == BoxTypes.MovieExtends)
{
MovieExtendsBox = new MovieExtendsBox(this);
MovieExtendsBox.Read(reader);
}
else if (tmpBox.Type == BoxTypes.ObjectDescriptor) // iods
{
_objectDescriptor = new ObjectDescriptorBox();
_objectDescriptor.Read(reader);
}
else if (tmpBox.Type == BoxTypes.UserData) // udta
{
_userData = new UserDataBox();
_userData.Read(reader);
}
// some cases below for things we currently ignore, thus we skip over them...
else
{
byte[] buffer = new byte[tmpBox.Size];
reader.Read(buffer, 0, (int)tmpBox.Size);
//reader.BaseStream.Position = (long)(tmpBox.Size + tmpBox.Offset); // ignore for now
Debug.WriteLine(string.Format("Unknown box type {0} in MovieMetadataBox (this), skipped", tmpBox.Type.ToString()));
}
}
TrackBoxes = new TrackBox[tbcount];
for (int i = 0; i < tbcount; i++)
{
TrackBoxes[i] = tmpTBs[i];
}
}
}
public void AddTrackBox(TrackBox tbox)
{
TrackBoxes[MovieHeaderBox.NextTrackID - 1] = tbox;
tbox.TrackHeaderBox.TrackID = MovieHeaderBox.NextTrackID;
MovieHeaderBox.NextTrackID++;
}
public override void Read(BoxReader reader)
{
long testpos = reader.BaseStream.Position;
using (new SizeChecker(this, reader)) {
base.Read(reader);
MovieHeaderBox.Read(reader);
// Don't assume any order in the boxes within this after the header.
// (The order depends on the brand.)
int tbcount = 0;
TrackBox[] tmpTBs = new TrackBox[10];
while (reader.BaseStream.Position < (long)(this.Size + this.Offset)) {
long pos = reader.BaseStream.Position;
Box tmpBox = new Box(BoxTypes.Any);
tmpBox.Read(reader);
reader.BaseStream.Position = pos;
if (tmpBox.Type == BoxTypes.Track)
{
TrackBox tb = new TrackBox(this, MovieHeaderBox.TimeScale);
tb.Read(reader);
tmpTBs[tbcount] = tb;
tbcount++;
}
else if (tmpBox.Type == BoxTypes.MovieExtends)
{
MovieExtendsBox = new MovieExtendsBox(this);
MovieExtendsBox.Read(reader);
}
else if (tmpBox.Type == BoxTypes.ObjectDescriptor) // iods
{
_objectDescriptor = new ObjectDescriptorBox();
_objectDescriptor.Read(reader);
}
else if (tmpBox.Type == BoxTypes.UserData) // udta
{
_userData = new UserDataBox();
_userData.Read(reader);
}
// some cases below for things we currently ignore, thus we skip over them...
else
{
byte[] buffer = new byte[tmpBox.Size];
reader.Read(buffer, 0, (int)tmpBox.Size);
//reader.BaseStream.Position = (long)(tmpBox.Size + tmpBox.Offset); // ignore for now
Debug.WriteLine(string.Format("Unknown box type {0} in MovieMetadataBox (this), skipped", tmpBox.Type.ToString()));
}
}
TrackBoxes = new TrackBox[tbcount];
for (int i = 0; i < tbcount; i++)
{
TrackBoxes[i] = tmpTBs[i];
}
}
}
public void AddTrackBox(TrackBox tbox)
{
TrackBoxes[MovieHeaderBox.NextTrackID - 1] = tbox;
tbox.TrackHeaderBox.TrackID = MovieHeaderBox.NextTrackID;
MovieHeaderBox.NextTrackID++;
}
public MediaBox(TrackBox inParent)
: base(BoxTypes.Media)
{
parent = inParent;
}