CompressionCodecFactory compressionCodecs = new CompressionCodecFactory(conf);
final CompressionCodec codec = compressionCodecs.getCodec(path);
if (codec != null)
stream = new DataInputStream(codec.createInputStream(stream));
PcapReader reader = initPcapReader(stream, conf);
return new PcapRecordReader(reader, start, length, baseStream, stream, reporter);
}