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# http://pyrocko.org - GPLv3
#
# The Pyrocko Developers, 21st Century
# ---|P------/S----------~Lg----------
from __future__ import division, absolute_import
from struct import unpack
import os
import re
import logging
from pyrocko import trace
from pyrocko.util import reuse, ensuredirs
from .io_common import FileLoadError, FileSaveError
logger = logging.getLogger('pyrocko.io.mseed')
class CodeTooLong(FileSaveError):
pass
def iload(filename, load_data=True):
from pyrocko import mseed_ext
have_zero_rate_traces = False
try:
traces = []
for tr in mseed_ext.get_traces(filename, load_data):
network, station, location, channel = tr[1:5]
tmin = float(tr[5])/float(mseed_ext.HPTMODULUS)
tmax = float(tr[6])/float(mseed_ext.HPTMODULUS)
try:
deltat = reuse(1.0/float(tr[7]))
except ZeroDivisionError:
have_zero_rate_traces = True
continue
ydata = tr[8]
traces.append(trace.Trace(
network, station, location, channel, tmin, tmax,
deltat, ydata))
for tr in traces:
yield tr
except (OSError, mseed_ext.MSeedError) as e:
raise FileLoadError(str(e)+' (file: %s)' % filename)
if have_zero_rate_traces:
logger.warning(
'Ignoring traces with sampling rate of zero in file %s '
'(maybe LOG traces)' % filename)
def as_tuple(tr):
from pyrocko import mseed_ext
itmin = int(round(tr.tmin*mseed_ext.HPTMODULUS))
itmax = int(round(tr.tmax*mseed_ext.HPTMODULUS))
srate = 1.0/tr.deltat
return (tr.network, tr.station, tr.location, tr.channel,
itmin, itmax, srate, tr.get_ydata())
def save(traces, filename_template, additional={}, overwrite=True,
record_length=4096):
from pyrocko import mseed_ext
assert record_length in (2**exp for exp in range(8, 20))
fn_tr = {}
for tr in traces:
for code, maxlen, val in zip(
['network', 'station', 'location', 'channel'],
[2, 5, 2, 3],
tr.nslc_id):
if len(val) > maxlen:
raise CodeTooLong(
'%s code too long to be stored in MSeed file: %s' %
(code, val))
fn = tr.fill_template(filename_template, **additional)
if not overwrite and os.path.exists(fn):
raise FileSaveError('File exists: %s' % fn)
if fn not in fn_tr:
fn_tr[fn] = []
fn_tr[fn].append(tr)
for fn, traces_thisfile in fn_tr.items():
trtups = []
traces_thisfile.sort(key=lambda a: a.full_id)
for tr in traces_thisfile:
trtups.append(as_tuple(tr))
ensuredirs(fn)
try:
mseed_ext.store_traces(trtups, fn, record_length)
except mseed_ext.MSeedError as e:
raise FileSaveError(
str(e) + ' (while storing traces to file \'%s\')' % fn)
return list(fn_tr.keys())
tcs = {}
def detect(first512):
if len(first512) < 256:
return False
rec = first512
try:
sequence_number = int(rec[:6])
except Exception:
return False
if sequence_number < 0:
return False
type_code = rec[6:7]
if type_code in b'DRQM':
bads = []
for sex in '<>':
bad = False
fmt = sex + '6s1s1s5s2s3s2s10sH2h4Bl2H'
vals = unpack(fmt, rec[:48])
fmt_btime = sex + 'HHBBBBH'
tvals = unpack(fmt_btime, vals[7])
if tvals[1] < 1 or tvals[1] > 367 or tvals[2] > 23 or \
tvals[3] > 59 or tvals[4] > 60 or tvals[6] > 9999:
bad = True
bads.append(bad)
if all(bads):
return False
else:
if type_code not in b'VAST':
return False
continuation_code = rec[7:8]
if continuation_code != b' ':
return False
blockette_type = rec[8:8+3].decode()
if not re.match(r'^\d\d\d$', blockette_type):
return False
try:
blockette_length = int(rec[11:11+4])
except Exception:
return False
if blockette_length < 7:
return False
return True
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