/// <summary>
/// 分析amf文件
/// </summary>
public void AnalyzeAmfFile()
{
try
{
//初始化文件读取对象
_reader = new FileStream(_filePath, FileMode.Open, FileAccess.Read);
//读取并分析文件头
_buffer = new byte[_amfHeaderSize];
int res = _reader.Read(_buffer, 0, _amfHeaderSize);
if (res != _amfHeaderSize)
throw new FileFormatException("amf文件格式不正确");
this._headerInfo = AmfMediaDecoder.AnalyzeFileHeader(_buffer);
//读取并分析文件帧信息
UInt32 tagOffset = _headerInfo.DataSize + 76 + 8;
UInt32 tagLength = _headerInfo.FileSize - tagOffset;
_buffer = new byte[tagLength];
_reader.Position = tagOffset;
res = _reader.Read(_buffer, 0, (int)tagLength);
if (res != (int)tagLength)
throw new FileFormatException("amf文件格式不正确");
this._frames = AmfMediaDecoder.AnalyzeFileFrame(_buffer, ref _videoLength);
}
catch (Exception ex)
{
throw new Exception("解析amf文件异常", ex);
}
}
/// <summary>
/// 释放申请的资源
/// </summary>
public void Dispose()
{
try
{
_headerInfo = null;
_frames.Clear();
if (_reader != null)
{
_reader.Close();
_reader = null;
}
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine(ex.ToString());
}
}
/// <summary>
/// 分析amf文件头部
/// </summary>
/// <param name="header">文件头字符数组</param>
/// <returns></returns>
public static AmfHeadInfo AnalyzeFileHeader(Byte[] header)
{
try
{
if (header.Length != 76)
return null;
System.IO.MemoryStream ms = new System.IO.MemoryStream(header);
var temp = new AmfHeadInfo
{
Format = AmfTools.Byte2String(ms.ReadBytesExtend(0, 4)),
FileSize = AmfTools.ConvertToInt32(header, 4) + 8,
AudioFlag = AmfTools.SubArray(header, 8, 4),
AudioHeadSize = AmfTools.ConvertToInt32(header, 12),
AudioCodec = new Char4 { Value = AmfTools.Byte2String(ms.ReadBytesExtend(16, 4)) },//AmfTools.SubArray(header,16,4)},
AudioBitRate = AmfTools.ConvertToInt32(header, 20),
ChannelCount = AmfTools.ConvertToInt32(header, 24),
SamplingRate = AmfTools.ConvertToInt32(header, 28),
SamplingTime = AmfTools.ConvertToInt32(header, 32),
AudioFrameCount = AmfTools.ConvertToInt32(header, 36),
VideoFlag = AmfTools.SubArray(header, 40, 4),
VideoHeadSize = AmfTools.ConvertToInt32(header, 44),
VideoCodec = new Char4 { Value = AmfTools.Byte2String(ms.ReadBytesExtend(48, 4)) },//AmfTools.SubArray(header, 48, 4),
Width = AmfTools.ConvertToInt32(header, 52),
Height = AmfTools.ConvertToInt32(header, 56),
VideoFrameRate = AmfTools.ConvertToInt32(header, 60),
VideoFrameCount = AmfTools.ConvertToInt32(header, 64),
DataBlockFlag = AmfTools.SubArray(header, 68, 4),
DataSize = AmfTools.ConvertToInt32(header, 72)
};
ms.Close();
return temp;
}
catch
{
throw;
}
}
