diff options
Diffstat (limited to 'src/Jellyfin.MediaEncoding.Keyframes/Matroska/Extensions/EbmlReaderExtensions.cs')
| -rw-r--r-- | src/Jellyfin.MediaEncoding.Keyframes/Matroska/Extensions/EbmlReaderExtensions.cs | 257 |
1 files changed, 128 insertions, 129 deletions
diff --git a/src/Jellyfin.MediaEncoding.Keyframes/Matroska/Extensions/EbmlReaderExtensions.cs b/src/Jellyfin.MediaEncoding.Keyframes/Matroska/Extensions/EbmlReaderExtensions.cs index 75d5aafe0..e068cac84 100644 --- a/src/Jellyfin.MediaEncoding.Keyframes/Matroska/Extensions/EbmlReaderExtensions.cs +++ b/src/Jellyfin.MediaEncoding.Keyframes/Matroska/Extensions/EbmlReaderExtensions.cs @@ -3,176 +3,175 @@ using System.Buffers.Binary; using Jellyfin.MediaEncoding.Keyframes.Matroska.Models; using NEbml.Core; -namespace Jellyfin.MediaEncoding.Keyframes.Matroska.Extensions +namespace Jellyfin.MediaEncoding.Keyframes.Matroska.Extensions; + +/// <summary> +/// Extension methods for the <see cref="EbmlReader"/> class. +/// </summary> +internal static class EbmlReaderExtensions { /// <summary> - /// Extension methods for the <see cref="EbmlReader"/> class. + /// Traverses the current container to find the element with <paramref name="identifier"/> identifier. /// </summary> - internal static class EbmlReaderExtensions + /// <param name="reader">An instance of <see cref="EbmlReader"/>.</param> + /// <param name="identifier">The element identifier.</param> + /// <returns>A value indicating whether the element was found.</returns> + internal static bool FindElement(this EbmlReader reader, ulong identifier) { - /// <summary> - /// Traverses the current container to find the element with <paramref name="identifier"/> identifier. - /// </summary> - /// <param name="reader">An instance of <see cref="EbmlReader"/>.</param> - /// <param name="identifier">The element identifier.</param> - /// <returns>A value indicating whether the element was found.</returns> - internal static bool FindElement(this EbmlReader reader, ulong identifier) + while (reader.ReadNext()) { - while (reader.ReadNext()) + if (reader.ElementId.EncodedValue == identifier) { - if (reader.ElementId.EncodedValue == identifier) - { - return true; - } + return true; } - - return false; } - /// <summary> - /// Reads the current position in the file as an unsigned integer converted from binary. - /// </summary> - /// <param name="reader">An instance of <see cref="EbmlReader"/>.</param> - /// <returns>The unsigned integer.</returns> - internal static uint ReadUIntFromBinary(this EbmlReader reader) + return false; + } + + /// <summary> + /// Reads the current position in the file as an unsigned integer converted from binary. + /// </summary> + /// <param name="reader">An instance of <see cref="EbmlReader"/>.</param> + /// <returns>The unsigned integer.</returns> + internal static uint ReadUIntFromBinary(this EbmlReader reader) + { + var buffer = new byte[4]; + reader.ReadBinary(buffer, 0, 4); + return BinaryPrimitives.ReadUInt32BigEndian(buffer); + } + + /// <summary> + /// Reads from the start of the file to retrieve the SeekHead segment. + /// </summary> + /// <param name="reader">An instance of <see cref="EbmlReader"/>.</param> + /// <returns>Instance of <see cref="SeekHead"/>.</returns> + internal static SeekHead ReadSeekHead(this EbmlReader reader) + { + reader = reader ?? throw new ArgumentNullException(nameof(reader)); + + if (reader.ElementPosition != 0) { - var buffer = new byte[4]; - reader.ReadBinary(buffer, 0, 4); - return BinaryPrimitives.ReadUInt32BigEndian(buffer); + throw new InvalidOperationException("File position must be at 0"); } - /// <summary> - /// Reads from the start of the file to retrieve the SeekHead segment. - /// </summary> - /// <param name="reader">An instance of <see cref="EbmlReader"/>.</param> - /// <returns>Instance of <see cref="SeekHead"/>.</returns> - internal static SeekHead ReadSeekHead(this EbmlReader reader) + // Skip the header + if (!reader.FindElement(MatroskaConstants.SegmentContainer)) { - reader = reader ?? throw new ArgumentNullException(nameof(reader)); - - if (reader.ElementPosition != 0) - { - throw new InvalidOperationException("File position must be at 0"); - } - - // Skip the header - if (!reader.FindElement(MatroskaConstants.SegmentContainer)) - { - throw new InvalidOperationException("Expected a segment container"); - } + throw new InvalidOperationException("Expected a segment container"); + } - reader.EnterContainer(); + reader.EnterContainer(); - long? tracksPosition = null; - long? cuesPosition = null; - long? infoPosition = null; - // The first element should be a SeekHead otherwise we'll have to search manually - if (!reader.FindElement(MatroskaConstants.SeekHead)) - { - throw new InvalidOperationException("Expected a SeekHead"); - } + long? tracksPosition = null; + long? cuesPosition = null; + long? infoPosition = null; + // The first element should be a SeekHead otherwise we'll have to search manually + if (!reader.FindElement(MatroskaConstants.SeekHead)) + { + throw new InvalidOperationException("Expected a SeekHead"); + } + reader.EnterContainer(); + while (reader.FindElement(MatroskaConstants.Seek)) + { reader.EnterContainer(); - while (reader.FindElement(MatroskaConstants.Seek)) + reader.ReadNext(); + var type = (ulong)reader.ReadUIntFromBinary(); + switch (type) { - reader.EnterContainer(); - reader.ReadNext(); - var type = (ulong)reader.ReadUIntFromBinary(); - switch (type) - { - case MatroskaConstants.Tracks: - reader.ReadNext(); - tracksPosition = (long)reader.ReadUInt(); - break; - case MatroskaConstants.Cues: - reader.ReadNext(); - cuesPosition = (long)reader.ReadUInt(); - break; - case MatroskaConstants.Info: - reader.ReadNext(); - infoPosition = (long)reader.ReadUInt(); - break; - } - - reader.LeaveContainer(); - - if (tracksPosition.HasValue && cuesPosition.HasValue && infoPosition.HasValue) - { + case MatroskaConstants.Tracks: + reader.ReadNext(); + tracksPosition = (long)reader.ReadUInt(); + break; + case MatroskaConstants.Cues: + reader.ReadNext(); + cuesPosition = (long)reader.ReadUInt(); + break; + case MatroskaConstants.Info: + reader.ReadNext(); + infoPosition = (long)reader.ReadUInt(); break; - } } reader.LeaveContainer(); - if (!tracksPosition.HasValue || !cuesPosition.HasValue || !infoPosition.HasValue) + if (tracksPosition.HasValue && cuesPosition.HasValue && infoPosition.HasValue) { - throw new InvalidOperationException("SeekHead is missing or does not contain Info, Tracks and Cues positions"); + break; } - - return new SeekHead(infoPosition.Value, tracksPosition.Value, cuesPosition.Value); } - /// <summary> - /// Reads from SegmentContainer to retrieve the Info segment. - /// </summary> - /// <param name="reader">An instance of <see cref="EbmlReader"/>.</param> - /// <param name="position">The position of the info segment relative to the Segment container.</param> - /// <returns>Instance of <see cref="Info"/>.</returns> - internal static Info ReadInfo(this EbmlReader reader, long position) + reader.LeaveContainer(); + + if (!tracksPosition.HasValue || !cuesPosition.HasValue || !infoPosition.HasValue) { - reader.ReadAt(position); + throw new InvalidOperationException("SeekHead is missing or does not contain Info, Tracks and Cues positions"); + } - double? duration = null; - reader.EnterContainer(); - // Mandatory element - reader.FindElement(MatroskaConstants.TimestampScale); - var timestampScale = reader.ReadUInt(); + return new SeekHead(infoPosition.Value, tracksPosition.Value, cuesPosition.Value); + } - if (reader.FindElement(MatroskaConstants.Duration)) - { - duration = reader.ReadFloat(); - } + /// <summary> + /// Reads from SegmentContainer to retrieve the Info segment. + /// </summary> + /// <param name="reader">An instance of <see cref="EbmlReader"/>.</param> + /// <param name="position">The position of the info segment relative to the Segment container.</param> + /// <returns>Instance of <see cref="Info"/>.</returns> + internal static Info ReadInfo(this EbmlReader reader, long position) + { + reader.ReadAt(position); - reader.LeaveContainer(); + double? duration = null; + reader.EnterContainer(); + // Mandatory element + reader.FindElement(MatroskaConstants.TimestampScale); + var timestampScale = reader.ReadUInt(); - return new Info((long)timestampScale, duration); + if (reader.FindElement(MatroskaConstants.Duration)) + { + duration = reader.ReadFloat(); } - /// <summary> - /// Enters the Tracks segment and reads all tracks to find the specified type. - /// </summary> - /// <param name="reader">Instance of <see cref="EbmlReader"/>.</param> - /// <param name="tracksPosition">The relative position of the tracks segment.</param> - /// <param name="type">The track type identifier.</param> - /// <returns>The first track number with the specified type.</returns> - /// <exception cref="InvalidOperationException">Stream type is not found.</exception> - internal static ulong FindFirstTrackNumberByType(this EbmlReader reader, long tracksPosition, ulong type) - { - reader.ReadAt(tracksPosition); + reader.LeaveContainer(); + return new Info((long)timestampScale, duration); + } + + /// <summary> + /// Enters the Tracks segment and reads all tracks to find the specified type. + /// </summary> + /// <param name="reader">Instance of <see cref="EbmlReader"/>.</param> + /// <param name="tracksPosition">The relative position of the tracks segment.</param> + /// <param name="type">The track type identifier.</param> + /// <returns>The first track number with the specified type.</returns> + /// <exception cref="InvalidOperationException">Stream type is not found.</exception> + internal static ulong FindFirstTrackNumberByType(this EbmlReader reader, long tracksPosition, ulong type) + { + reader.ReadAt(tracksPosition); + + reader.EnterContainer(); + while (reader.FindElement(MatroskaConstants.TrackEntry)) + { reader.EnterContainer(); - while (reader.FindElement(MatroskaConstants.TrackEntry)) - { - reader.EnterContainer(); - // Mandatory element - reader.FindElement(MatroskaConstants.TrackNumber); - var trackNumber = reader.ReadUInt(); + // Mandatory element + reader.FindElement(MatroskaConstants.TrackNumber); + var trackNumber = reader.ReadUInt(); - // Mandatory element - reader.FindElement(MatroskaConstants.TrackType); - var trackType = reader.ReadUInt(); + // Mandatory element + reader.FindElement(MatroskaConstants.TrackType); + var trackType = reader.ReadUInt(); + reader.LeaveContainer(); + if (trackType == MatroskaConstants.TrackTypeVideo) + { reader.LeaveContainer(); - if (trackType == MatroskaConstants.TrackTypeVideo) - { - reader.LeaveContainer(); - return trackNumber; - } + return trackNumber; } + } - reader.LeaveContainer(); + reader.LeaveContainer(); - throw new InvalidOperationException($"No stream with type {type} found"); - } + throw new InvalidOperationException($"No stream with type {type} found"); } } |