private bool findSPSandPPS()
{
/*
* SPS and PPS parameters are stored in the avcC box
* You may find really useful information about this box
* in the document ISO-IEC 14496-15, part 5.2.4.1.1
* The box's structure is described there
* <pre>
* aligned(8) class AVCDecoderConfigurationRecord {
* unsigned int(8) configurationVersion = 1;
* unsigned int(8) AVCProfileIndication;
* unsigned int(8) profile_compatibility;
* unsigned int(8) AVCLevelIndication;
* bit(6) reserved = ‘111111’b;
* unsigned int(2) lengthSizeMinusOne;
* bit(3) reserved = ‘111’b;
* unsigned int(5) numOfSequenceParameterSets;
* for (i=0; i< numOfSequenceParameterSets; i++) {
* unsigned int(16) sequenceParameterSetLength ;
* bit(8*sequenceParameterSetLength) sequenceParameterSetNALUnit;
* }
* unsigned int(8) numOfPictureParameterSets;
* for (i=0; i< numOfPictureParameterSets; i++) {
* unsigned int(16) pictureParameterSetLength;
* bit(8*pictureParameterSetLength) pictureParameterSetNALUnit;
* }
* }
* </pre>
*/
try {
// TODO: Here we assume that numOfSequenceParameterSets = 1, numOfPictureParameterSets = 1 !
// Here we extract the SPS parameter
fis.SkipBytes(7);
spsLength = 0xFF & fis.ReadByte();
sps = new byte[spsLength];
fis.Read(sps, 0, spsLength);
// Here we extract the PPS parameter
fis.SkipBytes(2);
ppsLength = 0xFF & fis.ReadByte();
pps = new byte[ppsLength];
fis.Read(pps, 0, ppsLength);
} catch (IOException e) {
return(false);
}
return(true);
}
private void parse(System.String path, long len)
{
ByteBuffer byteBuffer;
long sum = 0, newlen = 0;
byte[] buffer = new byte[8];
Java.Lang.String name = null;
if (!path.Equals(""))
{
mBoxes.Add(path, (Long)(mPos - 8));
}
while (sum < len)
{
mFile.Read(buffer, 0, 8);
mPos += 8; sum += 8;
if (validBoxName(buffer))
{
name = new Java.Lang.String(buffer, 4, 4);
if (buffer[3] == 1)
{
// 64 bits atom size
mFile.Read(buffer, 0, 8);
mPos += 8; sum += 8;
byteBuffer = ByteBuffer.Wrap(buffer, 0, 8);
newlen = byteBuffer.GetLong() - 16;
}
else
{
// 32 bits atom size
byteBuffer = ByteBuffer.Wrap(buffer, 0, 4);
newlen = byteBuffer.GetInt() - 8;
}
// 1061109559+8 correspond to "????" in ASCII the HTC Desire S seems to write that sometimes, maybe other phones do
// "wide" atom would produce a newlen == 0, and we shouldn't throw an exception because of that
if (newlen < 0 || newlen == 1061109559)
{
throw new IOException();
}
Log.d(TAG, "Atom -> name: " + name + " position: " + mPos + ", length: " + newlen);
sum += newlen;
parse(path + '/' + name, newlen);
}
else
{
if (len < 8)
{
mFile.Seek(mFile.FilePointer - 8 + len);
sum += len - 8;
}
else
{
int skipped = mFile.SkipBytes((int)(len - 8));
if (skipped < ((int)(len - 8)))
{
throw new IOException();
}
mPos += len - 8;
sum += len - 8;
}
}
}
}
