// Get the Apple Tag.
public override TagLib.Tag FindTag(TagTypes type, bool create)
{
if (type == TagTypes.Apple)
{
if (tag == null && create)
{
tag = new Mpeg4AppleTag(this);
}
return(tag);
}
return(null);
}
// Read the file.
private void Read(ReadStyle propertiesStyle)
{
// Create a dummie outer box, as perscribed by the specs.
Mpeg4FileBox file_box = new Mpeg4FileBox(this);
// Find the movie box and item text. If the movie box doen'type exist, an
// exception will be thrown on the next call, but if there is no movie
// box, the file can'type possibly be valid.
Mpeg4IsoMovieBox moov_box = (Mpeg4IsoMovieBox)file_box.FindChildDeep("moov");
Mpeg4AppleItemListBox ilst_box = (Mpeg4AppleItemListBox)moov_box.FindChildDeep("ilst");
// If we have a ItemListBox, deparent it.
if (ilst_box != null)
{
ilst_box.RemoveFromParent();
}
// Create the tag.
tag = new Mpeg4AppleTag(ilst_box, this);
// If we're not reading properties, we're done.
if (propertiesStyle == ReadStyle.None)
{
return;
}
// Get the movie header box.
Mpeg4IsoMovieHeaderBox mvhd_box = (Mpeg4IsoMovieHeaderBox)moov_box.FindChildDeep("mvhd");
Mpeg4IsoAudioSampleEntry sample_entry = null;
// Find a TrackBox with a sound Handler.
foreach (Mpeg4Box box in moov_box.Children)
{
if (box.BoxType == "trak")
{
// If the handler isn'type sound, it could be metadata or video or
// any number of other things.
Mpeg4IsoHandlerBox hdlr_box = (Mpeg4IsoHandlerBox)box.FindChildDeep("hdlr");
if (hdlr_box == null || hdlr_box.HandlerType != "soun")
{
continue;
}
// This track SHOULD contain at least one sample entry.
sample_entry = (Mpeg4IsoAudioSampleEntry)box.FindChildDeep(typeof(Mpeg4IsoAudioSampleEntry));
break;
}
}
// If we have a MovieHeaderBox, deparent it.
if (mvhd_box != null)
{
mvhd_box.RemoveFromParent();
}
// If we have a SampleEntry, deparent it.
if (sample_entry != null)
{
sample_entry.RemoveFromParent();
}
// Read the properties.
properties = new Mpeg4Properties(mvhd_box, sample_entry, propertiesStyle);
}
