bool nextImpl() override
{
size_t size_decompressed;
size_t size_compressed_without_checksum;
size_compressed = readCompressedData(size_decompressed, size_compressed_without_checksum);
if (!size_compressed)
return false;
memory.resize(size_decompressed + LZ4::ADDITIONAL_BYTES_AT_END_OF_BUFFER);
working_buffer = Buffer(&memory[0], &memory[size_decompressed]);
decompress(working_buffer.begin(), size_decompressed, size_compressed_without_checksum);
return true;
}
void ThreadedDyscoColumn<DataType>::loadBlock(size_t blockIndex)
{
if(blockIndex < nBlocksInFile())
{
readCompressedData(blockIndex, _packedBlockReadBuffer.data(), _blockSize);
const size_t nPolarizations = _shape[0], nChannels = _shape[1],
nRows = nRowsInBlock(),
nMetaFloats = metaDataFloatCount(nRows, nPolarizations, nChannels, _antennaCount);
unsigned char* symbolStart = _packedBlockReadBuffer.data() + nMetaFloats*sizeof(float);
BytePacker::unpack(_bitsPerSymbol, _unpackedSymbolReadBuffer.data(), symbolStart, symbolCount(nRows, nPolarizations, nChannels));
float* metaData = reinterpret_cast<float*>(_packedBlockReadBuffer.data());
initializeDecode(_timeBlockBuffer.get(), metaData, nRows, _antennaCount);
uint64_t startRow = getRowIndex(blockIndex);
_timeBlockBuffer->resize(nRows);
for(size_t blockRow=0; blockRow!=nRows; ++blockRow)
{
int a1 = (*_ant1Col)(startRow + blockRow), a2 = (*_ant2Col)(startRow + blockRow);
decode(_timeBlockBuffer.get(), _unpackedSymbolReadBuffer.data(), blockRow, a1, a2);
}
}
_currentBlock = blockIndex;
_isCurrentBlockChanged = false;
}