/// <summary>
/// Parses boxes for a specified range, looking for tags and
/// properties.
/// </summary>
/// <param name="start">
/// A <see cref="long" /> value specifying the seek position
/// at which to start reading.
/// </param>
/// <param name="end">
/// A <see cref="long" /> value specifying the seek position
/// at which to stop reading.
/// </param>
/// <param name="handler">
/// A <see cref="IsoHandlerBox" /> object that applied to the
/// range being searched.
/// </param>
private void ParseTagAndProperties (long start, long end,
IsoHandlerBox handler)
{
BoxHeader header;
for (long position = start; position < end;
position += header.TotalBoxSize) {
header = new BoxHeader (file, position);
ByteVector type = header.BoxType;
if (type == BoxType.Moov ||
type == BoxType.Mdia ||
type == BoxType.Minf ||
type == BoxType.Stbl ||
type == BoxType.Trak) {
ParseTagAndProperties (
header.HeaderSize + position,
header.TotalBoxSize + position,
handler);
} else if (type == BoxType.Stsd) {
stsd_boxes.Add (BoxFactory.CreateBox (
file, header, handler));
} else if (type == BoxType.Hdlr) {
handler = BoxFactory.CreateBox (file,
header, handler) as
IsoHandlerBox;
} else if (mvhd_box == null &&
type == BoxType.Mvhd) {
mvhd_box = BoxFactory.CreateBox (file,
header, handler) as
IsoMovieHeaderBox;
} else if (udta_box == null &&
type == BoxType.Udta) {
udta_box = BoxFactory.CreateBox (file,
header, handler) as
IsoUserDataBox;
} else if (type == BoxType.Mdat) {
mdat_start = position;
mdat_end = position + header.TotalBoxSize;
}
if (header.TotalBoxSize == 0)
break;
}
}
/// <summary>
/// Resets all internal fields.
/// </summary>
private void ResetFields ()
{
mvhd_box = null;
udta_box = null;
moov_tree = null;
udta_tree = null;
stco_boxes.Clear ();
stsd_boxes.Clear ();
mdat_start = -1;
mdat_end = -1;
}
/// <summary>
/// Reads the file with a specified read style.
/// </summary>
/// <param name="propertiesStyle">
/// A <see cref="ReadStyle" /> value specifying at what level
/// of accuracy to read the media properties, or <see
/// cref="ReadStyle.None" /> to ignore the properties.
/// </param>
private void Read(ReadStyle propertiesStyle)
{
// TODO: Support Id3v2 boxes!!!
tag = new CombinedTag();
Mode = AccessMode.Read;
try {
FileParser parser = new FileParser(this);
if (propertiesStyle == ReadStyle.None)
{
parser.ParseTag();
}
else
{
parser.ParseTagAndProperties();
}
InvariantStartPosition = parser.MdatStartPosition;
InvariantEndPosition = parser.MdatEndPosition;
udta_box = parser.UserDataBox;
if (udta_box != null && udta_box.GetChild(BoxType.Meta)
!= null && udta_box.GetChild(BoxType.Meta
).GetChild(BoxType.Ilst) != null)
{
TagTypesOnDisk |= TagTypes.Apple;
}
if (udta_box == null)
{
udta_box = new IsoUserDataBox();
}
apple_tag = new AppleTag(udta_box);
tag.SetTags(apple_tag);
// If we're not reading properties, we're done.
if (propertiesStyle == ReadStyle.None)
{
Mode = AccessMode.Closed;
return;
}
// Get the movie header box.
IsoMovieHeaderBox mvhd_box = parser.MovieHeaderBox;
if (mvhd_box == null)
{
Mode = AccessMode.Closed;
throw new CorruptFileException(
"mvhd box not found.");
}
IsoAudioSampleEntry audio_sample_entry =
parser.AudioSampleEntry;
IsoVisualSampleEntry visual_sample_entry =
parser.VisualSampleEntry;
// Read the properties.
properties = new Properties(mvhd_box.Duration,
audio_sample_entry, visual_sample_entry);
} finally {
Mode = AccessMode.Closed;
}
}
