/// <summary>
/// 编码脚本Tag
/// </summary>
/// <param name="spsInfo">解析后的sps信息</param>
/// <param name="hasAudio">是否有音频</param>
/// <param name="frameRate">帧率 默认25d 即每秒25帧</param>
/// <returns></returns>
public byte[] EncoderScriptTag(SPSInfo spsInfo, bool hasAudio = false, double frameRate = 25d)
{
byte[] buffer = FlvArrayPool.Rent(1024);
try
{
FlvMessagePackWriter flvMessagePackWriter = new FlvMessagePackWriter(buffer);
//flv body script tag
//flv body tag header
FlvTags flvTags = new FlvTags
{
Type = TagType.ScriptData,
//flv body tag body
DataTagsData = new Amf3
{
Amf3Metadatas = new List <IAmf3Metadata>
{
new Amf3Metadata_Duration {
Value = 0d
},
new Amf3Metadata_VideoDataRate {
Value = 0d
},
new Amf3Metadata_VideoCodecId {
Value = 7d
},
new Amf3Metadata_FrameRate {
Value = frameRate
},
new Amf3Metadata_Width()
{
Value = spsInfo.width
},
new Amf3Metadata_Height()
{
Value = spsInfo.height
},
}
}
};
if (hasAudio)
{
flvTags.DataTagsData.Amf3Metadatas.Add(new Amf3Metadata_AudioCodecId());
flvTags.DataTagsData.Amf3Metadatas.Add(new Amf3Metadata_AudioSampleRate());
flvTags.DataTagsData.Amf3Metadatas.Add(new Amf3Metadata_AudioSampleSize());
flvTags.DataTagsData.Amf3Metadatas.Add(new Amf3Metadata_AudioStereo());
}
flvMessagePackWriter.WriteFlvTag(flvTags);
flvMessagePackWriter.WriteUInt32((uint)(flvTags.DataSize + 11));
return(flvMessagePackWriter.FlushAndGetArray());
}
finally
{
FlvArrayPool.Return(buffer);
}
}
/// <summary>
/// 编码首帧视频，即videoTag[0]
/// <para>
/// 注意：本方法已写入<see cref="previousTagSize"/>
/// </para>
/// </summary>
/// <param name="sps"></param>
/// <param name="pps"></param>
/// <param name="sei"></param>
/// <returns></returns>
public byte[] EncoderFirstVideoTag(H264NALU sps, H264NALU pps, H264NALU sei)
{
byte[] buffer = FlvArrayPool.Rent(2048);
try
{
FlvMessagePackWriter flvMessagePackWriter = new FlvMessagePackWriter(buffer);
var rawData = h264Decoder.DiscardEmulationPreventionBytes(sps.RawData);
ExpGolombReader h264GolombReader = new ExpGolombReader(rawData);
SPSInfo spsInfo = h264GolombReader.ReadSPS();
//flv body video tag
//flv body tag header
FlvTags flvTags = new FlvTags
{
Type = TagType.Video,
Timestamp = (uint)sps.Timestamp,
TimestampExt = 0,
StreamId = 0,
//flv body tag body
VideoTagsData = new VideoTags()
};
flvTags.VideoTagsData.FrameType = FrameType.KeyFrame;
flvTags.VideoTagsData.VideoData = new AvcVideoPacke
{
AvcPacketType = AvcPacketType.SequenceHeader,
CompositionTime = 0
};
AVCDecoderConfigurationRecord aVCDecoderConfigurationRecord = new AVCDecoderConfigurationRecord
{
AVCProfileIndication = spsInfo.profileIdc,
ProfileCompatibility = (byte)spsInfo.profileCompat,
AVCLevelIndication = spsInfo.levelIdc,
NumOfPictureParameterSets = 1,
PPSBuffer = pps.RawData,
SPSBuffer = sps.RawData
};
flvTags.VideoTagsData.VideoData.AVCDecoderConfiguration = aVCDecoderConfigurationRecord;
flvMessagePackWriter.WriteUInt32(previousTagSize);
flvMessagePackWriter.WriteFlvTag(flvTags);
var data = flvMessagePackWriter.FlushAndGetArray();
previousTagSize = (uint)(flvTags.DataSize + 11);
return(data);
}
finally
{
FlvArrayPool.Return(buffer);
}
}
/// <summary>
///
/// </summary>
private void CreateFlvKeyFrame(ref FlvMessagePackWriter flvMessagePackWriter, string key, byte[] spsRawData, byte[] ppsRawData, SPSInfo spsInfo, uint previousTagSize = 0)
{
int currentMarkPosition = 0;
int nextMarkPosition = 0;
currentMarkPosition = flvMessagePackWriter.GetCurrentPosition();
//flv body script tag
CreateScriptTagFrame(ref flvMessagePackWriter, spsInfo.width, spsInfo.height, previousTagSize);
nextMarkPosition = flvMessagePackWriter.GetCurrentPosition();
//flv body video tag
uint scriptTagFramePreviousTagSize = (uint)(nextMarkPosition - currentMarkPosition - PreviousTagSizeFixedLength);
AVCDecoderConfigurationRecord aVCDecoderConfigurationRecord = new AVCDecoderConfigurationRecord();
aVCDecoderConfigurationRecord.AVCProfileIndication = spsInfo.profileIdc;
aVCDecoderConfigurationRecord.ProfileCompatibility = (byte)spsInfo.profileCompat;
aVCDecoderConfigurationRecord.AVCLevelIndication = spsInfo.levelIdc;
aVCDecoderConfigurationRecord.NumOfPictureParameterSets = 1;
aVCDecoderConfigurationRecord.PPSBuffer = ppsRawData;
aVCDecoderConfigurationRecord.SPSBuffer = spsRawData;
currentMarkPosition = flvMessagePackWriter.GetCurrentPosition();
CreateVideoTag0Frame(ref flvMessagePackWriter, scriptTagFramePreviousTagSize, aVCDecoderConfigurationRecord);
nextMarkPosition = flvMessagePackWriter.GetCurrentPosition();
//flv body video tag 0
uint videoTag0PreviousTagSize = (uint)(nextMarkPosition - currentMarkPosition - PreviousTagSizeFixedLength);
//cache PreviousTagSize
FlvFrameInfoDict.AddOrUpdate(key, new FlvFrameInfo {
PreviousTagSize = videoTag0PreviousTagSize
}, (a, b) => {
b.PreviousTagSize = videoTag0PreviousTagSize;
return(b);
});
}
public byte[] CreateFlvFrame(List <H264NALU> nALUs, int minimumLength = 65535)
{
byte[] buffer = FlvArrayPool.Rent(minimumLength);
try
{
FlvMessagePackWriter flvMessagePackWriter = new FlvMessagePackWriter(buffer);
int currentMarkPosition = 0;
int nextMarkPosition = 0;
H264NALU sps = null, pps = null;
SPSInfo spsInfo = new SPSInfo();
foreach (var naln in nALUs)
{
string key = naln.GetKey();
if (sps != null && pps != null)
{
if (VideoSPSDict.TryGetValue(key, out var spsInfoCache))
{
if (spsInfoCache.height != spsInfo.height && spsInfoCache.width != spsInfo.width)
{
if (FlvFrameInfoDict.TryGetValue(key, out FlvFrameInfo flvFrameInfo))
{
CreateFlvKeyFrame(ref flvMessagePackWriter, key, sps.RawData, pps.RawData, spsInfo, flvFrameInfo.PreviousTagSize);
FlvFirstFrameCache.TryRemove(key, out _);
FlvFirstFrameCache.TryAdd(key, flvMessagePackWriter.FlushAndGetArray());
VideoSPSDict.TryUpdate(key, spsInfo, spsInfo);
flvFrameInfo.LastFrameInterval = 0;
FlvFrameInfoDict.TryUpdate(key, flvFrameInfo, flvFrameInfo);
}
}
sps = null;
pps = null;
}
else
{
CreateFlvKeyFrame(ref flvMessagePackWriter, key, sps.RawData, pps.RawData, spsInfo, 0);
FlvFirstFrameCache.TryAdd(key, flvMessagePackWriter.FlushAndGetArray());
VideoSPSDict.TryAdd(key, spsInfo);
sps = null;
pps = null;
}
}
//7 8 6 5 1 1 1 1 7 8 6 5 1 1 1 1 1 7 8 6 5 1 1 1 1 1
switch (naln.NALUHeader.NalUnitType)
{
case 5: // IDR
case 1: // I/P/B
if (FlvFrameInfoDict.TryGetValue(key, out FlvFrameInfo flvFrameInfo))
{
currentMarkPosition = flvMessagePackWriter.GetCurrentPosition();
CreateVideoTagOtherFrame(ref flvMessagePackWriter, flvFrameInfo, naln);
nextMarkPosition = flvMessagePackWriter.GetCurrentPosition();
uint tmpPreviousTagSize = (uint)(nextMarkPosition - currentMarkPosition - PreviousTagSizeFixedLength);
flvFrameInfo.PreviousTagSize = tmpPreviousTagSize;
flvFrameInfo.LastFrameInterval += naln.LastFrameInterval;
FlvFrameInfoDict.TryUpdate(key, flvFrameInfo, flvFrameInfo);
}
break;
case 7: // sps
sps = naln;
var rawData = H264Decoder.DiscardEmulationPreventionBytes(naln.RawData);
ExpGolombReader h264GolombReader = new ExpGolombReader(rawData);
spsInfo = h264GolombReader.ReadSPS();
break;
case 8: // pps
pps = naln;
break;
case 6: //SEI
break;
default:
break;
}
}
return(flvMessagePackWriter.FlushAndGetArray());
}
finally
{
FlvArrayPool.Return(buffer);
}
}
