SequenceExtension::SequenceExtension( BitReader &hdr )
{
init();
hdr.reset();
ahabassert( hdr.readbits( 32 ) == 0x000001b5 );
ahabassert( hdr.readbits( 4 ) == 1 );
escape_bit = hdr.readbits( 1 );
profile = hdr.readbits( 3 );
level = hdr.readbits( 4 );
progressive_sequence = hdr.readbits( 1 );
chroma_format = hdr.readbits( 2 );
horizontal_size_extension = hdr.readbits( 2 );
vertical_size_extension = hdr.readbits( 2 );
bit_rate_extension = hdr.readbits( 12 );
mpegassert( hdr.readbits( 1 ) == 1 );
vbv_buffer_size_extension = hdr.readbits( 8 );
low_delay = hdr.readbits( 1 );
frame_rate_extension_n = hdr.readbits( 2 );
frame_rate_extension_d = hdr.readbits( 5 );
/* Check conformance limits */
if ( escape_bit ) {
throw ConformanceLimitExceeded();
}
/* Simple profile or Main profile */
if ( (profile != 5) && (profile != 4) ) {
throw ConformanceLimitExceeded();
}
/* 4:2:0 only */
if ( chroma_format != 1 ) {
throw ConformanceLimitExceeded();
}
}
bool init ( BitReader br )
{
br.reset();
if ( br.getByte() != 0x64
|| br.getByte() != 0x58
|| br.getByte() != 0x20
|| br.getByte() != 0x25 )
{
return false;
}
// * dca.c dca_exss_parse_header
br.skip(8); // user data
_ssIndex = br.getInt(2);
bool blownUp(br.getBool());
_headerSize = br.getInt(blownUp ? 12 : 8);
//hdLen = ((hdHdr[6] & 0xf) << 11) + (hdHdr[7] << 3) + ((hdHdr[8] >> 5) & 7) + 1;
_hdSize = br.getInt(blownUp ? 20: 16) + 1;
return true;
}
PictureCodingExtension::PictureCodingExtension( BitReader &hdr )
{
init();
hdr.reset();
ahabassert( hdr.readbits( 32 ) == 0x000001b5 );
ahabassert( hdr.readbits( 4 ) == 8 );
f_code_fh = hdr.readbits( 4 );
f_code_fv = hdr.readbits( 4 );
f_code_bh = hdr.readbits( 4 );
f_code_bv = hdr.readbits( 4 );
intra_dc_precision = hdr.readbits( 2 );
picture_structure = hdr.readbits( 2 );
top_field_first = hdr.readbits( 1 );
frame_pred_frame_dct = hdr.readbits( 1 );
concealment_motion_vectors = hdr.readbits( 1 );
q_scale_type = hdr.readbits( 1 );
intra_vlc_format = hdr.readbits( 1 );
alternate_scan = hdr.readbits( 1 );
repeat_first_field = hdr.readbits( 1 );
chroma_420_type = hdr.readbits( 1 );
progressive_frame = hdr.readbits( 1 );
if ( picture_structure != 3 ) {
fprintf( stderr, "Ahab does not support field pictures.\n" );
throw ConformanceLimitExceeded();
}
mpegassert( ((f_code_fh >= 1) && (f_code_fh <= 9)) || (f_code_fh == 15) );
mpegassert( ((f_code_fv >= 1) && (f_code_fv <= 9)) || (f_code_fv == 15) );
mpegassert( ((f_code_bh >= 1) && (f_code_bh <= 9)) || (f_code_bh == 15) );
mpegassert( ((f_code_bv >= 1) && (f_code_bv <= 9)) || (f_code_bv == 15) );
}
QuantMatrixExtension::QuantMatrixExtension( BitReader &hdr )
{
init();
hdr.reset();
ahabassert( hdr.readbits( 32 ) == 0x000001b5 );
ahabassert( hdr.readbits( 4 ) == 3 );
load_intra_quantiser_matrix = hdr.readbits( 1 );
for ( int i = 0; i < 64; i++ ) {
intra_quantiser_matrix[ mpeg2_normal_scan[ i ] ] =
load_intra_quantiser_matrix
? hdr.readbits( 8 )
: default_intra_quantiser_matrix[ i ];
mpegassert( intra_quantiser_matrix[ mpeg2_normal_scan[ i ] ] != 0 );
}
load_non_intra_quantiser_matrix = hdr.readbits( 1 );
for ( int i = 0; i < 64; i++ ) {
non_intra_quantiser_matrix[ mpeg2_normal_scan[ i ] ] =
load_non_intra_quantiser_matrix ? hdr.readbits( 8 ) : 16;
mpegassert( intra_quantiser_matrix[ mpeg2_normal_scan[ i ] ] != 0 );
}
}
bool init ( BitReader br )
{
br.reset();
// 16 bit formats
if ( br.getByte() == 0x7f
&& br.getByte() == 0xfe
&& br.getByte() == 0x80
&& br.getByte() == 0x01 )
{
_is14Bit = false;
}
else
{
// 14 bit formats
br.reset();
if (br.getByte() == 0x1f
&& br.getByte() == 0xff
&& br.getByte() == 0xe8
&& br.getByte() == 0x00
&& br.getByte() == 0x07
&& br.getByte(4) == 0xf)
{
_is14Bit = true;
/*
* The original code was this, not sure I can parse the 14bit the same as the
* 16 bit, but I can look at that later if there are problems
sampleBlocks = ((be2uint16(hdr16[2]) << 4) & 0x70)
| ((be2uint16(hdr16[3]) >> 10) & 0x0f);
++sampleBlocks;
amode = (be2uint16(hdr16[4]) >> 4) & 0x3f;
sfreq = (be2uint16(hdr16[4]) >> 0) & 0x0f;
lfe = (be2uint16(hdr16[6]) >> 11) & 0x03;
*/
}
else
{
return false; // invalid frame data
}
}
_isNormalFrame = br.getBool(); // 1
_shortSamples = br.getInt(5); // 6
_isCrcPresent = br.getBool(); // 7
_sampleBlocks = br.getInt(7) + 1; // 14
_frameSize = br.getInt(14) + 1; // 28
_channelLayout = br.getInt(6);
_sampleIndex = br.getInt(4);
_bitRate = br.getInt(5);
_downMix = br.getBool();
_dynamicRange = br.getBool();
_timeStamp = br.getBool();
_auxiliaryData = br.getBool();
_hdcd = br.getBool();
_externalDescription = br.getInt(3);
_externalCoding = br.getBool();
_aspf = br.getBool();
_lfe = br.getInt(2);
_predictorHistory = br.getBool();
if ( _isCrcPresent )
_crc = br.getInt(16);
_multirateInter = br.getBool();
_version = br.getInt(4);
_copyHistory = br.getInt(2);
_sourcePcmResolution = br.getInt(3);
_frontSum = br.getBool();
_surroundSum = br.getBool();
_dialogNormalization = br.getInt(4);
return true;
}
