/// <summary>
/// Reads the chapter information from the specified file.
/// </summary>
/// <param name="fileHandle">The handle to the file from which to read the chapter information.</param>
/// <returns>A new instance of a <see cref="ChapterList"/> object containing the information
/// about the chapters for the file.</returns>
internal static ChapterList ReadFromFile(IntPtr fileHandle)
{
ChapterList list = new ChapterList();
IntPtr chapterListPointer = IntPtr.Zero;
int chapterCount = 0;
NativeMethods.MP4ChapterType chapterType = NativeMethods.MP4GetChapters(fileHandle, ref chapterListPointer, ref chapterCount, NativeMethods.MP4ChapterType.Qt);
if (chapterType != NativeMethods.MP4ChapterType.None && chapterCount != 0)
{
IntPtr currentChapterPointer = chapterListPointer;
for (int i = 0; i < chapterCount; i++)
{
NativeMethods.MP4Chapter currentChapter = currentChapterPointer.ReadStructure <NativeMethods.MP4Chapter>();
TimeSpan duration = TimeSpan.FromMilliseconds(currentChapter.duration);
string title = Encoding.UTF8.GetString(currentChapter.title);
if ((currentChapter.title[0] == 0xFE && currentChapter.title[1] == 0xFF) ||
(currentChapter.title[0] == 0xFF && currentChapter.title[1] == 0xFE))
{
title = Encoding.Unicode.GetString(currentChapter.title);
}
title = title.Substring(0, title.IndexOf('\0'));
list.AddInternal(new Chapter()
{
Duration = duration, Title = title
});
currentChapterPointer = IntPtr.Add(currentChapterPointer, Marshal.SizeOf(currentChapter));
}
}
else
{
int timeScale = NativeMethods.MP4GetTimeScale(fileHandle);
long duration = NativeMethods.MP4GetDuration(fileHandle);
list.AddInternal(new Chapter()
{
Duration = TimeSpan.FromSeconds(duration / timeScale), Title = "Chapter 1"
});
}
if (chapterListPointer != IntPtr.Zero)
{
NativeMethods.MP4Free(chapterListPointer);
}
return(list);
}
/// <summary>
/// Loads the metadata for this file.
/// </summary>
public void Load()
{
IntPtr fileHandle = NativeMethods.MP4Read(this.fileName);
if (fileHandle != IntPtr.Zero)
{
try
{
this.metadataTags = MetadataTags.ReadFromFile(fileHandle);
this.chapters = ChapterList.ReadFromFile(fileHandle);
}
finally
{
NativeMethods.MP4Close(fileHandle);
}
}
}
