IntraReferenceSamples IntraPred::calcReference( MatrixRef<Sample> source, TB &tb, Picture &pic )
{
IntraReferenceAvailability avail( tb.size( ) );
IntraReferenceSamples samples( tb.size( ) );
bool atLeasOneAvailable = false;
Position tbLumaPos = pic.scalePositionToLuma( tb.pos, tb.plane );
Position targetLumaPos = pic.scalePositionToLuma( tb.pos.move( -1, -1 ), tb.plane );
//corner
avail.Corner = checkSampleAvailability( tbLumaPos, targetLumaPos, pic );
if( avail.Corner )
{
samples.Corner = source( tb.pos.x - 1, tb.pos.y - 1 );
atLeasOneAvailable = true;
}
int offsetLimit = 2 * tb.size( );
for( int offset = 0; offset < offsetLimit; ++offset )
{
//left
targetLumaPos = pic.scalePositionToLuma( tb.pos.move( -1, offset ), tb.plane );
avail.Left[ offset ] = checkSampleAvailability( tbLumaPos, targetLumaPos, pic );
if( avail.Left[ offset ] )
{
samples.Left[ offset ] = source( tb.pos.x - 1, tb.pos.y + offset );
atLeasOneAvailable = true;
}
//top
targetLumaPos = pic.scalePositionToLuma( tb.pos.move( offset, -1 ), tb.plane );
avail.Top[ offset ] = checkSampleAvailability( tbLumaPos, targetLumaPos, pic );
if( avail.Top[ offset ] )
{
samples.Top[ offset ] = source( tb.pos.x + offset, tb.pos.y - 1 );
atLeasOneAvailable = true;
}
}
if( !atLeasOneAvailable )
{
Sample defaultSample = pic.pps->sps->getDefaultSampleValue( tb.plane );
samples.Corner = defaultSample;
for( int offset = 0; offset < offsetLimit; ++offset )
{
samples.Left[ offset ] = defaultSample;
samples.Top[ offset ] = defaultSample;
}
}
else
{
fillMissingReferences( samples, avail );
}
return samples;
}
