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Merged
Teque5 merged 1 commit into from
Jan 6, 2026
+52 −27
Merged

fix capture byte boundaries for archives #124

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2 changes: 1 addition & 1 deletion sigmf/__init__.py
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Original file line number Diff line number Diff line change
Expand Up @@ -5,7 +5,7 @@
# SPDX-License-Identifier: LGPL-3.0-or-later

# version of this python module
__version__ = "1.4.0"
__version__ = "1.5.0"
# matching version of the SigMF specification
__specification__ = "1.2.6"

Expand Down
32 changes: 23 additions & 9 deletions sigmf/sigmffile.py
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Original file line number Diff line number Diff line change
Expand Up @@ -182,7 +182,9 @@ class SigMFFile(SigMFMetafile):
]
VALID_KEYS = {GLOBAL_KEY: VALID_GLOBAL_KEYS, CAPTURE_KEY: VALID_CAPTURE_KEYS, ANNOTATION_KEY: VALID_ANNOTATION_KEYS}

def __init__(self, metadata=None, data_file=None, global_info=None, skip_checksum=False, map_readonly=True, autoscale=True):
def __init__(
self, metadata=None, data_file=None, global_info=None, skip_checksum=False, map_readonly=True, autoscale=True
):
"""
API for SigMF I/O

Expand Down Expand Up @@ -339,7 +341,7 @@ def __getitem__(self, sli):
if self.is_complex_data:
data = data.view(np.complex64)
# for single-channel complex data, flatten the last dimension
if data.ndim > 1 and self.get_num_channels() == 1:
if data.ndim > 1 and self.num_channels == 1:
data = data.flatten()
return data[0] if isinstance(sli, int) else data
else:
Expand Down Expand Up @@ -509,7 +511,7 @@ def get_capture_start(self, index):
raise SigMFAccessError("Capture {} does not have required {} key".format(index, self.START_INDEX_KEY))
return start

def get_capture_byte_boundarys(self, index):
def get_capture_byte_boundaries(self, index):
"""
Returns a tuple of the file byte range in a dataset of a given SigMF
capture of the form [start, stop). This function works on either
Expand All @@ -531,7 +533,13 @@ def get_capture_byte_boundarys(self, index):

end_byte = start_byte
if index == len(self.get_captures()) - 1: # last captures...data is the rest of the file
end_byte = self.data_file.stat().st_size - self.get_global_field(self.TRAILING_BYTES_KEY, 0)
if self.data_file is not None:
file_size = self.data_file.stat().st_size
elif self.data_buffer is not None:
file_size = len(self.data_buffer.getbuffer())
else:
raise SigMFFileError("Neither data_file nor data_buffer is available")
end_byte = file_size - self.get_global_field(self.TRAILING_BYTES_KEY, 0)
else:
end_byte += (
(self.get_capture_start(index + 1) - self.get_capture_start(index))
Expand All @@ -540,6 +548,15 @@ def get_capture_byte_boundarys(self, index):
)
return (start_byte, end_byte)

def get_capture_byte_boundarys(self, index):
warnings.warn(
"get_capture_byte_boundarys() is deprecated and will be removed in a future version of sigmf. "
"Use get_capture_byte_boundaries() instead.",
DeprecationWarning,
stacklevel=2,
)
return self.get_capture_byte_boundaries(index)

def add_annotation(self, start_index, length=None, metadata=None):
"""
Insert annotation at start_index with length (if != None).
Expand Down Expand Up @@ -789,7 +806,7 @@ def read_samples_in_capture(self, index=0):
data : ndarray
Samples are returned as an array of float or complex, with number of dimensions equal to NUM_CHANNELS_KEY.
"""
cb = self.get_capture_byte_boundarys(index)
cb = self.get_capture_byte_boundaries(index)
if (cb[1] - cb[0]) % (self.get_sample_size() * self.num_channels):
warnings.warn(
f"Capture `{index}` in `{self.data_file}` does not contain "
Expand Down Expand Up @@ -826,10 +843,7 @@ def read_samples(self, start_index=0, count=-1):
else:
raise SigMFFileError("No signal data file has been associated with the metadata.")
first_byte = start_index * self.get_sample_size() * self.num_channels

if not self._is_conforming_dataset():
warnings.warn(f"Recording dataset appears non-compliant, resulting data may be erroneous")
return self._read_datafile(first_byte, count * self.get_num_channels())
return self._read_datafile(first_byte, count * self.num_channels)

def _read_datafile(self, first_byte, nitems):
"""
Expand Down
45 changes: 28 additions & 17 deletions tests/test_sigmffile.py
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Original file line number Diff line number Diff line change
Expand Up @@ -254,8 +254,8 @@ def test_000(self) -> None:
meta = self.prepare(TEST_U8_DATA0, TEST_U8_META0, np.uint8, autoscale=False)
self.assertEqual(256, meta._count_samples())
self.assertTrue(meta._is_conforming_dataset())
self.assertTrue((0, 0), meta.get_capture_byte_boundarys(0))
self.assertTrue((0, 256), meta.get_capture_byte_boundarys(1))
self.assertTrue((0, 0), meta.get_capture_byte_boundaries(0))
self.assertTrue((0, 256), meta.get_capture_byte_boundaries(1))
self.assertTrue(np.array_equal(TEST_U8_DATA0, meta.read_samples()))
self.assertTrue(np.array_equal(np.array([]), meta.read_samples_in_capture(0)))
self.assertTrue(np.array_equal(TEST_U8_DATA0, meta.read_samples_in_capture(1)))
Expand All @@ -265,8 +265,8 @@ def test_001(self) -> None:
meta = self.prepare(TEST_U8_DATA1, TEST_U8_META1, np.uint8, autoscale=False)
self.assertEqual(192, meta._count_samples())
self.assertFalse(meta._is_conforming_dataset())
self.assertTrue((32, 160), meta.get_capture_byte_boundarys(0))
self.assertTrue((160, 224), meta.get_capture_byte_boundarys(1))
self.assertTrue((32, 160), meta.get_capture_byte_boundaries(0))
self.assertTrue((160, 224), meta.get_capture_byte_boundaries(1))
self.assertTrue(np.array_equal(np.arange(128), meta.read_samples_in_capture(0)))
self.assertTrue(np.array_equal(np.arange(128, 192), meta.read_samples_in_capture(1)))

Expand All @@ -275,8 +275,8 @@ def test_002(self) -> None:
meta = self.prepare(TEST_U8_DATA2, TEST_U8_META2, np.uint8, autoscale=False)
self.assertEqual(192, meta._count_samples())
self.assertFalse(meta._is_conforming_dataset())
self.assertTrue((32, 160), meta.get_capture_byte_boundarys(0))
self.assertTrue((160, 224), meta.get_capture_byte_boundarys(1))
self.assertTrue((32, 160), meta.get_capture_byte_boundaries(0))
self.assertTrue((160, 224), meta.get_capture_byte_boundaries(1))
self.assertTrue(np.array_equal(np.arange(128), meta.read_samples_in_capture(0)))
self.assertTrue(np.array_equal(np.arange(128, 192), meta.read_samples_in_capture(1)))

Expand All @@ -285,9 +285,9 @@ def test_003(self) -> None:
meta = self.prepare(TEST_U8_DATA3, TEST_U8_META3, np.uint8, autoscale=False)
self.assertEqual(192, meta._count_samples())
self.assertFalse(meta._is_conforming_dataset())
self.assertTrue((32, 64), meta.get_capture_byte_boundarys(0))
self.assertTrue((64, 160), meta.get_capture_byte_boundarys(1))
self.assertTrue((160, 224), meta.get_capture_byte_boundarys(2))
self.assertTrue((32, 64), meta.get_capture_byte_boundaries(0))
self.assertTrue((64, 160), meta.get_capture_byte_boundaries(1))
self.assertTrue((160, 224), meta.get_capture_byte_boundaries(2))
self.assertTrue(np.array_equal(np.arange(32), meta.read_samples_in_capture(0)))
self.assertTrue(np.array_equal(np.arange(32, 128), meta.read_samples_in_capture(1)))
self.assertTrue(np.array_equal(np.arange(128, 192), meta.read_samples_in_capture(2)))
Expand All @@ -297,8 +297,8 @@ def test_004(self) -> None:
meta = self.prepare(TEST_U8_DATA4, TEST_U8_META4, np.uint8, autoscale=False)
self.assertEqual(96, meta._count_samples())
self.assertFalse(meta._is_conforming_dataset())
self.assertTrue((32, 96), meta.get_capture_byte_boundarys(0))
self.assertTrue((96, 160), meta.get_capture_byte_boundarys(1))
self.assertTrue((32, 96), meta.get_capture_byte_boundaries(0))
self.assertTrue((96, 160), meta.get_capture_byte_boundaries(1))
self.assertTrue(np.array_equal(np.arange(64).repeat(2).reshape(-1, 2), meta.read_samples_in_capture(0)))
self.assertTrue(np.array_equal(np.arange(64, 96).repeat(2).reshape(-1, 2), meta.read_samples_in_capture(1)))

Expand All @@ -317,13 +317,24 @@ def test_slicing_rf32(self) -> None:

def test_slicing_multiple_channels(self) -> None:
"""slice multiple channels"""
meta_raw = self.prepare(TEST_U8_DATA4, TEST_U8_META4, np.uint8, autoscale=False)
meta_scaled = self.prepare(TEST_U8_DATA4, TEST_U8_META4, np.uint8, autoscale=False) # use raw data for this test

meta = self.prepare(TEST_U8_DATA4, TEST_U8_META4, np.uint8, autoscale=False)
channelized = np.array(TEST_U8_DATA4).reshape((-1, 2))
self.assertTrue(np.array_equal(meta_scaled[:][:], channelized))
self.assertTrue(np.array_equal(meta_raw[10:20, 0], meta_raw.read_samples()[10:20, 0]))
self.assertTrue(np.array_equal(meta_scaled[0], channelized[0]))
self.assertTrue(np.array_equal(meta_scaled[1, :], channelized[1]))
self.assertTrue(np.array_equal(meta[:][:], channelized))
self.assertTrue(np.array_equal(meta[10:20, 0], meta.read_samples()[10:20, 0]))
self.assertTrue(np.array_equal(meta[0], channelized[0]))
self.assertTrue(np.array_equal(meta[1, :], channelized[1]))

def test_boundaries(self) -> None:
"""capture byte boundaries from pairs & archives"""
# get a meta pair and archive
meta = self.prepare(TEST_U8_DATA3, TEST_U8_META3, np.uint8)
arc_path = self.temp_dir / "arc.sigmf"
meta.tofile(arc_path, toarchive=True)
arc = sigmf.fromfile(arc_path)
for bdx in range(3):
self.assertEqual(meta.get_capture_byte_boundaries(bdx), arc.get_capture_byte_boundaries(bdx))
self.assertTrue(np.array_equal(meta.read_samples_in_capture(bdx), arc.read_samples_in_capture(bdx)))


def simulate_capture(sigmf_md, n, capture_len):
Expand Down