void Dump(bool force, MMalBuffer buffer, int len)
{
if (force)
{
_logger.Error("buffer {0}", buffer.ToString());
StringBuilder sb = new StringBuilder();
for (int i = 0; i < buffer.Data.Length && i < len; ++i)
{
if ((i % 4) == 0)
{
sb.Append(" ");
}
sb.AppendFormat("{0:x2}", buffer.Data[i]);
if (((i + 1) % 30) == 0)
{
sb.Append("\r\n");
}
}
_logger.Error(sb.ToString());
}
}
public void Parse(MMalBuffer buffer, MMalBuffer next)
{
if (_logger.IsDebugEnabled)
{
_logger.Debug("buffer.Len {0}, presentation time {1}", buffer.Length, buffer.Timestamp);
}
if (buffer.Data.Length < 4)
{
return;
}
bool pictureEndMarker = false;
MemoryStream ms = new MemoryStream(buffer.Data);
if (NaluIsStartCode(ms) == 0)
{
Dump(true, buffer, 10);
throw new Exception("No Start Code");
}
long nalStart = ms.Position;
while (ms.Position < ms.Length)
{
int nalAndTrailingSize;
int nalSize;
int nalEnd;
pictureEndMarker = false;
nalAndTrailingSize = nalSize = NaluNextStartCode(ms);
if (true)
{
nalSize = NaluPayloadEnd(ms);
}
byte[] nalunit = new byte[nalSize];
ms.Read(nalunit, 0, (int)nalSize);
ms.Seek(nalStart, SeekOrigin.Begin);
byte nalunitType = (byte)(nalunit[0] & 0x1F);
// Now that we have found (& copied) a NAL unit, process it if it's of special interest to us:
if (IsVPS(nalunitType))
{
// Video parameter set
// We haven't yet parsed a frame rate from the stream.
// So parse this NAL unit to check whether frame rate information is present:
// uint num_units_in_tick = 0, time_scale = 0;
// AnalyzeVPS(ref num_units_in_tick, ref time_scale);
}
else if (IsSPS(nalunitType))
{
// Sequence parameter set
// We haven't yet parsed a frame rate from the stream.
// So parse this NAL unit to check whether frame rate information is present:
// uint num_units_in_tick = 0, time_scale = 0;
//AnalyzeSPS(nalunit, ref num_units_in_tick, ref time_scale);
//if (time_scale > 0 && num_units_in_tick > 0)
//{
// fFrameRate = fParsedFrameRate = time_scale / (DeltaTfiDivisor * num_units_in_tick);
//}
}
else if (IsPPS(nalunitType))
{
}
//else if (isSEI(nal_unit_type))
//{ // Supplemental enhancement information (SEI)
// analyze_sei_data(nal_unit_type);
// // Later, perhaps adjust "fPresentationTime" if we saw a "pic_timing" SEI payload??? #####
//}
// Now, check whether this NAL unit ends an 'access unit'.
// (RTP streamers need to know this in order to figure out whether or not to set the "M" bit.)
bool thisNALUnitEndsAccessUnit = false;
if (IsEOF(nalunitType))
{
// There is no next NAL unit, so we assume that this one ends the current 'access unit':
thisNALUnitEndsAccessUnit = true;
}
else if (UsuallyBeginsAccessUnit(nalunitType))
{
// These NAL units usually *begin* an access unit, so assume that they don't end one here:
thisNALUnitEndsAccessUnit = false;
}
else
{
// We need to check the *next* NAL unit to figure out whether
// the current NAL unit ends an 'access unit':
byte nextNalunitType = 0;
nalEnd = (int)ms.Position; // gf_bs_get_position(bs);
Debug.Assert(nalStart <= nalEnd);
Debug.Assert(nalEnd <= nalStart + nalAndTrailingSize);
if (nalEnd != nalStart + nalAndTrailingSize)
{
ms.Seek(nalStart + nalAndTrailingSize, SeekOrigin.Begin);
}
if (ms.Position == ms.Length)
{
if (next.Data.Length > 5)
{
nextNalunitType = (byte)(next.Data[4] & 0x1F);
}
}
else
{
ms.Seek(nalStart + nalAndTrailingSize, SeekOrigin.Begin);
/*consume next start code*/
nalStart = NaluNextStartCode(ms);
if (nalStart != 0)
{
Console.WriteLine("[avc-h264] invalid nal_size ({0})? Skipping {1} bytes to reach next start code\n", nalSize, nalStart);
//gf_bs_skip_bytes(bs, nal_start);
}
nalStart = NaluIsStartCode(ms);
if (nalStart == 0)
{
_logger.Error("avc-h264 error: no start code found");
break;
}
nalStart = ms.Position; // gf_bs_get_position(bs);
nalAndTrailingSize = nalSize = NaluNextStartCode(ms);
if (true)
{
nalSize = NaluPayloadEnd(ms);
}
byte[] nextNalunit = new byte[nalSize];
ms.Read(nextNalunit, 0, (int)nalSize);
nextNalunitType = (byte)(next.Data[4] & 0x1F);
ms.Seek(nalStart, SeekOrigin.Begin);
}
if (IsVCL(nextNalunitType))
{
// The high-order bit of the byte after the "nal_unit_header" tells us whether it's
// the start of a new 'access unit' (and thus the current NAL unit ends an 'access unit'):
byte byteAfter_nal_unit_header = 0x80;
if (next.Data.Length >= 5)
{
byteAfter_nal_unit_header = next.Data[5];
}
thisNALUnitEndsAccessUnit = (byteAfter_nal_unit_header & 0x80) != 0;
if (_logger.IsDebugEnabled)
{
_logger.Debug("End of NalUnit {0}", thisNALUnitEndsAccessUnit);
}
}
else if (UsuallyBeginsAccessUnit(nextNalunitType))
{
// The next NAL unit's type is one that usually appears at the start of an 'access unit',
// so we assume that the current NAL unit ends an 'access unit':
thisNALUnitEndsAccessUnit = true;
}
else
{
// The next NAL unit definitely doesn't start a new 'access unit',
// which means that the current NAL unit doesn't end one:
thisNALUnitEndsAccessUnit = false;
}
}
if (thisNALUnitEndsAccessUnit)
{
if (_logger.IsDebugEnabled)
{
_logger.Debug(" * ****This NAL unit ends the current access unit * ****\n");
}
pictureEndMarker = true;
}
if (_logger.IsDebugEnabled)
{
_logger.Debug("EndNalAccessUnit {0}, presentation {1}", thisNALUnitEndsAccessUnit, buffer.Timestamp);
}
// TODO
//byte[] tmp = new byte[nalSize + 4];
//tmp[3] = 1;
//Array.Copy(nalunit, 0, tmp, 4, nalunit.Length);
//Dump(tmp, numNalunit);
//numNalunit++;
_fragmenter.OnNewNalUnit(nalunit, thisNALUnitEndsAccessUnit, pictureEndMarker);
nalEnd = (int)ms.Position;
Debug.Assert(nalStart <= nalEnd);
Debug.Assert(nalEnd <= nalStart + nalAndTrailingSize);
if (nalEnd != nalStart + nalAndTrailingSize)
{
ms.Seek(nalStart + nalAndTrailingSize, SeekOrigin.Begin);
}
if (nalSize == 0)
{
break;
}
if (ms.Position == ms.Length)
{
break;
}
/*consume next start code*/
nalStart = NaluNextStartCode(ms);
if (nalStart != 0)
{
_logger.Error("[avc-h264] invalid nal_size ({0})? Skipping {1} bytes to reach next start code", nalSize, nalStart);
}
nalStart = NaluIsStartCode(ms);
if (nalStart == 0)
{
_logger.Error("[avc-h264] error: no start code found");
break;
}
nalStart = ms.Position;
} // while
}
