/// <summary>
/// Creates a box by reading it from a file given its header,
/// parent header, handler, and index in its parent.
/// </summary>
/// <param name="file">
/// A <see cref="TagLib.File" /> object containing the file
/// to read from.
/// </param>
/// <param name="header">
/// A <see cref="BoxHeader" /> object containing the header
/// of the box to create.
/// </param>
/// <param name="parent">
/// A <see cref="BoxHeader" /> object containing the header
/// of the parent box.
/// </param>
/// <param name="handler">
/// A <see cref="IsoHandlerBox" /> object containing the
/// handler that applies to the new box.
/// </param>
/// <param name="index">
/// A <see cref="int" /> value containing the index of the
/// new box in its parent.
/// </param>
/// <returns>
/// A newly created <see cref="Box" /> object.
/// </returns>
private static Box CreateBox(TagLib.File file,
BoxHeader header,
BoxHeader parent,
IsoHandlerBox handler,
int index)
{
// The first few children of an "stsd" are sample
// entries.
if (parent.BoxType == BoxType.Stsd &&
parent.Box is IsoSampleDescriptionBox box &&
index < box.EntryCount)
{
if (handler != null && handler.HandlerType == BoxType.Soun)
{
return(new IsoAudioSampleEntry(header, file, handler));
}
if (handler != null && handler.HandlerType == BoxType.Vide)
{
return(new IsoVisualSampleEntry(header, file, handler));
}
if (handler != null && handler.HandlerType == BoxType.Alis)
{
if (header.BoxType == BoxType.Text)
{
return(new TextBox(header, file, handler));
}
// This could be anything, so just parse it
return(new UnknownBox(header, file, handler));
}
return(new IsoSampleEntry(header,
file, handler));
}
// Standard items...
var type = header.BoxType;
if (type == BoxType.Mvhd)
{
return(new IsoMovieHeaderBox(header, file,
handler));
}
if (type == BoxType.Stbl)
{
return(new IsoSampleTableBox(header, file,
handler));
}
if (type == BoxType.Stsd)
{
return(new IsoSampleDescriptionBox(header,
file, handler));
}
if (type == BoxType.Stco)
{
return(new IsoChunkOffsetBox(header, file,
handler));
}
if (type == BoxType.Co64)
{
return(new IsoChunkLargeOffsetBox(header, file,
handler));
}
if (type == BoxType.Hdlr)
{
return(new IsoHandlerBox(header, file,
handler));
}
if (type == BoxType.Udta)
{
return(new IsoUserDataBox(header, file,
handler));
}
if (type == BoxType.Meta)
{
return(new IsoMetaBox(header, file, handler));
}
if (type == BoxType.Ilst)
{
return(new AppleItemListBox(header, file,
handler));
}
if (type == BoxType.Data)
{
return(new AppleDataBox(header, file, handler));
}
if (type == BoxType.Esds)
{
return(new AppleElementaryStreamDescriptor(
header, file, handler));
}
if (type == BoxType.Free || type == BoxType.Skip)
{
return(new IsoFreeSpaceBox(header, file,
handler));
}
if (type == BoxType.Mean || type == BoxType.Name)
{
return(new AppleAdditionalInfoBox(header, file,
handler));
}
// If we still don't have a tag, and we're inside an
// ItemListBox, load the box as an AnnotationBox
// (Apple tag item).
if (parent.BoxType == BoxType.Ilst)
{
return(new AppleAnnotationBox(header, file,
handler));
}
// Nothing good. Go generic.
return(new UnknownBox(header, file, handler));
}
/// <summary>
/// Creates a box by reading it from a file given its header
/// and handler.
/// </summary>
/// <param name="file">
/// A <see cref="TagLib.File" /> object containing the file
/// to read from.
/// </param>
/// <param name="header">
/// A <see cref="BoxHeader" /> object containing the header
/// of the box to create.
/// </param>
/// <returns>
/// A newly created <see cref="Box" /> object.
/// </returns>
public static Box CreateBox(TagLib.File file, BoxHeader header)
{
return(CreateBox(file, header, null));
}
/// <summary>
/// Creates a box by reading it from a file given its header
/// and handler.
/// </summary>
/// <param name="file">
/// A <see cref="TagLib.File" /> object containing the file
/// to read from.
/// </param>
/// <param name="header">
/// A <see cref="BoxHeader" /> object containing the header
/// of the box to create.
/// </param>
/// <param name="handler">
/// A <see cref="IsoHandlerBox" /> object containing the
/// handler that applies to the new box.
/// </param>
/// <returns>
/// A newly created <see cref="Box" /> object.
/// </returns>
public static Box CreateBox(TagLib.File file, BoxHeader header,
IsoHandlerBox handler)
{
return(CreateBox(file, header, BoxHeader.Empty,
handler, -1));
}
/// <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>
/// <param name="parents">
/// A <see cref="T:List" /> of <see cref="BoxHeader" /> parents.
/// </param>
private void ParseTagAndProperties(long start, long end,
IsoHandlerBox handler, List <BoxHeader> parents)
{
BoxHeader header;
for (var position = start;
position < end;
position += header.TotalBoxSize)
{
header = new BoxHeader(file, position);
var type = header.BoxType;
if (type == BoxType.Moov)
{
ParseTagAndProperties(header.HeaderSize + position,
header.TotalBoxSize + position,
handler,
AddParent(parents, header));
}
else if (type == BoxType.Mdia ||
type == BoxType.Minf ||
type == BoxType.Stbl ||
type == BoxType.Trak)
{
ParseTagAndProperties(
header.HeaderSize + position,
header.TotalBoxSize + position,
handler,
AddParent(parents, header));
}
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 (MovieHeaderBox == null &&
type == BoxType.Mvhd)
{
MovieHeaderBox = BoxFactory.CreateBox(file,
header, handler) as
IsoMovieHeaderBox;
}
else if (type == BoxType.Udta)
{
var udtaBox = BoxFactory.CreateBox(file,
header, handler) as
IsoUserDataBox;
// Since we can have multiple udta boxes, save the parent for each one
var new_parents = AddParent(
parents, header);
udtaBox.ParentTree = new_parents.ToArray();
udta_boxes.Add(udtaBox);
}
else if (type == BoxType.Mdat)
{
mdat_start = position;
MdatEndPosition = position + header.TotalBoxSize;
}
if (header.TotalBoxSize == 0)
{
break;
}
}
}
/// <summary>
/// Constructs and initializes a new instance of <see
/// cref="Box" /> with a specified header.
/// </summary>
/// <param name="header">
/// A <see cref="BoxHeader" /> object describing the new
/// instance.
/// </param>
protected Box(BoxHeader header) : this(header, null)
{
}
/// <summary>
/// Constructs and initializes a new instance of <see
/// cref="Box" /> with a specified header and handler.
/// </summary>
/// <param name="header">
/// A <see cref="BoxHeader" /> object describing the new
/// instance.
/// </param>
/// <param name="handler">
/// A <see cref="IsoHandlerBox" /> object containing the
/// handler that applies to the new instance, or <see
/// langword="null" /> if no handler applies.
/// </param>
protected Box(BoxHeader header, IsoHandlerBox handler)
{
this.header = header;
data_position = header.Position + header.HeaderSize;
Handler = handler;
}
