/*************************************************************************** * Copyright 2005 Raphaƫl Slinckx ****************************************************************************/ /* THIS FILE IS LICENSED UNDER THE MIT LICENSE AS OUTLINED IMMEDIATELY BELOW: * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. */ using System; using System.IO; using Entagged.Audioformats.Exceptions; namespace Entagged.Audioformats.Flac.Util { public class FlacInfoReader { public EncodingInfo Read(Stream raf) { //Read the infos-------------------------------------------------------- if (raf.Length == 0) { //Empty File throw new CannotReadException("Error: File empty"); } raf.Seek(0, SeekOrigin.Begin); //FLAC Header string byte[] b = new byte[4]; raf.Read(b, 0, b.Length); string flac = new string(System.Text.Encoding.ASCII.GetChars(b)); if (flac != "fLaC") { throw new CannotReadException("fLaC Header not found"); } MetadataBlockDataStreamInfo mbdsi = null; bool isLastBlock = false; while (!isLastBlock) { b = new byte[4]; raf.Read(b, 0, b.Length); MetadataBlockHeader mbh = new MetadataBlockHeader(b); if (mbh.BlockType == MetadataBlockHeader.BlockTypes.StreamInfo) { b = new byte[mbh.DataLength]; raf.Read(b, 0, b.Length); mbdsi = new MetadataBlockDataStreamInfo(b); if (!mbdsi.Valid) { throw new CannotReadException("FLAC StreamInfo not valid"); } break; } raf.Seek(raf.Position + mbh.DataLength, SeekOrigin.Begin); isLastBlock = mbh.IsLastBlock; mbh = null; //Free memory } EncodingInfo info = new EncodingInfo(); info.Duration = new TimeSpan(mbdsi.Length * TimeSpan.TicksPerSecond); info.ChannelNumber = mbdsi.ChannelNumber; info.SamplingRate = mbdsi.SamplingRate; info.EncodingType = mbdsi.EncodingType; info.ExtraEncodingInfos = ""; info.Bitrate = ComputeBitrate(mbdsi.Length, raf.Length); return info; } private int ComputeBitrate(int length, long size) { return (int) ((size / 1000) * 8 / length); } } }