public static async Task <MetadataItemsBox> CreateAsync(IBinaryStream stream, Box box)
{
if (!box.IsContainer)
{
throw new FormatException();
}
var metadataItemsBox = new MetadataItemsBox();
foreach (var subbox in box.Boxes)
{
switch (subbox.Name)
{
case "covr":
var data = subbox.Boxes.FirstOrDefault(a => a.Name == "data");
if (data != null)
{
metadataItemsBox.Cover = (await MetadataValueBox.CreateAsync(stream, data).ConfigureAwait(false)).DataLocation;
}
break;
default:
break;
}
}
return(metadataItemsBox);
}
public static async Task <ParseResult <Mpeg4File> > ParseAsync(IBinaryStream stream, ParseOptions options)
{
try
{
stream.Position = 4;
if (await stream.ReadStringAsync(4) != "ftyp")
{
return(ParseResult <Mpeg4File> .CreateUnknownFormat());
}
var file = new Mpeg4File();
stream.Position = 0;
var streamLength = await stream.GetLengthAsync().ConfigureAwait(false);
while (stream.Position < streamLength)
{
file.Boxes.Add(await Mpeg4File.ReadBoxAsync(stream, await stream.GetLengthAsync().ConfigureAwait(false)));
}
if (options == ParseOptions.Metadata)
{
var mediaData = file.Contains("mdat") ? file["mdat"] : null;
var metadataItems = file.Contains("moov.udta.meta.ilst") ? await MetadataItemsBox.CreateAsync(stream, file["moov.udta.meta.ilst"]).ConfigureAwait(false) : null;
var mediaHeader = file.Contains("moov.trak.mdia.mdhd") ? await MediaHeaderBox.CreateAsync(stream, file["moov.trak.mdia.mdhd"]).ConfigureAwait(false) : null;
file.Metadata = new Mpeg4Metadata(metadataItems?.Cover, mediaHeader?.Duration, mediaHeader?.TimeScale, mediaData?.Length);
}
return(ParseResult <Mpeg4File> .Create(file));
}
catch (Exception exception)
{
return(ParseResult <Mpeg4File> .Create(exception));
}
}