def pmt_to_tuple(p): elems = list() for i in range(pmt.pmt_length(p)): elem = pmt.pmt_tuple_ref(p, i) elems.append(pmt_to_python(elem)) return tuple(elems)
def parse_header(p, VERBOSE=False): dump = pmt.PMT_NIL info = dict() if(pmt.pmt_is_dict(p) is False): sys.stderr.write("Header is not a PMT dictionary: invalid or corrupt data file.\n") sys.exit(1) # GET FILE FORMAT VERSION NUMBER if(pmt.pmt_dict_has_key(p, pmt.pmt_string_to_symbol("version"))): r = pmt.pmt_dict_ref(p, pmt.pmt_string_to_symbol("version"), dump) version = pmt.pmt_to_long(r) if(VERBOSE): print "Version Number: {0}".format(version) else: sys.stderr.write("Could not find key 'version': invalid or corrupt data file.\n") sys.exit(1) # EXTRACT SAMPLE RATE if(pmt.pmt_dict_has_key(p, pmt.pmt_string_to_symbol("rx_rate"))): r = pmt.pmt_dict_ref(p, pmt.pmt_string_to_symbol("rx_rate"), dump) samp_rate = pmt.pmt_to_double(r) info["rx_rate"] = samp_rate if(VERBOSE): print "Sample Rate: {0:.2f} sps".format(samp_rate) else: sys.stderr.write("Could not find key 'sr': invalid or corrupt data file.\n") sys.exit(1) # EXTRACT TIME STAMP if(pmt.pmt_dict_has_key(p, pmt.pmt_string_to_symbol("rx_time"))): r = pmt.pmt_dict_ref(p, pmt.pmt_string_to_symbol("rx_time"), dump) pmt_secs = pmt.pmt_tuple_ref(r, 0) pmt_fracs = pmt.pmt_tuple_ref(r, 1) secs = float(pmt.pmt_to_uint64(pmt_secs)) fracs = pmt.pmt_to_double(pmt_fracs) t = secs + fracs info["rx_time"] = t if(VERBOSE): print "Seconds: {0:.6f}".format(t) else: sys.stderr.write("Could not find key 'time': invalid or corrupt data file.\n") sys.exit(1) # EXTRACT ITEM SIZE if(pmt.pmt_dict_has_key(p, pmt.pmt_string_to_symbol("size"))): r = pmt.pmt_dict_ref(p, pmt.pmt_string_to_symbol("size"), dump) dsize = pmt.pmt_to_long(r) info["size"] = dsize if(VERBOSE): print "Item size: {0}".format(dsize) else: sys.stderr.write("Could not find key 'size': invalid or corrupt data file.\n") sys.exit(1) # EXTRACT DATA TYPE if(pmt.pmt_dict_has_key(p, pmt.pmt_string_to_symbol("type"))): r = pmt.pmt_dict_ref(p, pmt.pmt_string_to_symbol("type"), dump) dtype = pmt.pmt_to_long(r) stype = ftype_to_string[dtype] info["type"] = stype if(VERBOSE): print "Data Type: {0} ({1})".format(stype, dtype) else: sys.stderr.write("Could not find key 'type': invalid or corrupt data file.\n") sys.exit(1) # EXTRACT COMPLEX if(pmt.pmt_dict_has_key(p, pmt.pmt_string_to_symbol("cplx"))): r = pmt.pmt_dict_ref(p, pmt.pmt_string_to_symbol("cplx"), dump) cplx = pmt.pmt_to_bool(r) info["cplx"] = cplx if(VERBOSE): print "Complex? {0}".format(cplx) else: sys.stderr.write("Could not find key 'cplx': invalid or corrupt data file.\n") sys.exit(1) # EXTRACT WHERE CURRENT SEGMENT STARTS if(pmt.pmt_dict_has_key(p, pmt.pmt_string_to_symbol("strt"))): r = pmt.pmt_dict_ref(p, pmt.pmt_string_to_symbol("strt"), dump) seg_start = pmt.pmt_to_uint64(r) info["hdr_len"] = seg_start info["extra_len"] = seg_start - HEADER_LENGTH info["has_extra"] = info["extra_len"] > 0 if(VERBOSE): print "Header Length: {0} bytes".format(info["hdr_len"]) print "Extra Length: {0}".format((info["extra_len"])) print "Extra Header? {0}".format(info["has_extra"]) else: sys.stderr.write("Could not find key 'strt': invalid or corrupt data file.\n") sys.exit(1) # EXTRACT SIZE OF DATA if(pmt.pmt_dict_has_key(p, pmt.pmt_string_to_symbol("bytes"))): r = pmt.pmt_dict_ref(p, pmt.pmt_string_to_symbol("bytes"), dump) nbytes = pmt.pmt_to_uint64(r) nitems = nbytes/dsize info["nitems"] = nitems info["nbytes"] = nbytes if(VERBOSE): print "Size of Data: {0} bytes".format(nbytes) print " {0} items".format(nitems) else: sys.stderr.write("Could not find key 'size': invalid or corrupt data file.\n") sys.exit(1) return info