def test_padding_and_aux_data_default_data(self, parse_code):
# No data given (default (empty) data should be assumed)
stream = Stream(
sequences=[
Sequence(
data_units=[DataUnit(parse_info=ParseInfo(parse_code=parse_code))]
)
]
)
assert autofill_parse_offsets(stream) == ([], [(0, 0)])
parse_info = stream["sequences"][0]["data_units"][0]["parse_info"]
assert parse_info["next_parse_offset"] == 13
assert parse_info["previous_parse_offset"] == 0
def test_padding_and_aux_data(self, parse_code):
stream = Stream(
sequences=[
Sequence(
data_units=[
# Next parse offset not given (should be treated as auto)
DataUnit(parse_info=ParseInfo(parse_code=parse_code)),
# Next parse offset is explicitly AUTO
DataUnit(
parse_info=ParseInfo(
parse_code=parse_code,
next_parse_offset=AUTO,
),
),
# Next parse offset is given (should not be modified)
DataUnit(
parse_info=ParseInfo(
parse_code=parse_code,
next_parse_offset=100,
),
),
]
)
]
)
for seq in stream["sequences"]:
for data_unit in seq["data_units"]:
if parse_code == tables.ParseCodes.padding_data:
data_unit["padding"] = Padding(bytes=b"1234")
elif parse_code == tables.ParseCodes.auxiliary_data:
data_unit["auxiliary_data"] = AuxiliaryData(bytes=b"1234")
assert autofill_parse_offsets(stream) == ([], [(0, 0), (0, 1), (0, 2)])
next_parse_offsets = [
data_unit["parse_info"]["next_parse_offset"]
for seq in stream["sequences"]
for data_unit in seq["data_units"]
]
assert next_parse_offsets == [13 + 4, 13 + 4, 100]
previous_parse_offsets = [
data_unit["parse_info"]["previous_parse_offset"]
for seq in stream["sequences"]
for data_unit in seq["data_units"]
]
assert previous_parse_offsets == [0, 0, 0]
def test_values_to_be_set_later_are_set_to_zero(self, parse_code, explicit_auto):
stream = Stream(
sequences=[
Sequence(
data_units=[
# An automatically set data unit
DataUnit(
parse_info=ParseInfo(
parse_code=parse_code,
)
),
# One which is explicitly set (and should not be overridden)
DataUnit(
parse_info=ParseInfo(
parse_code=parse_code,
next_parse_offset=100,
previous_parse_offset=200,
)
),
]
)
]
)
if explicit_auto:
parse_info = stream["sequences"][0]["data_units"][0]["parse_info"]
parse_info["next_parse_offset"] = AUTO
parse_info["previous_parse_offset"] = AUTO
assert autofill_parse_offsets(stream) == ([(0, 0)], [(0, 0)])
parse_info_0 = stream["sequences"][0]["data_units"][0]["parse_info"]
assert parse_info_0["next_parse_offset"] == 0
assert parse_info_0["previous_parse_offset"] == 0
parse_info_1 = stream["sequences"][0]["data_units"][1]["parse_info"]
assert parse_info_1["next_parse_offset"] == 100
assert parse_info_1["previous_parse_offset"] == 200
def test_finalizer_works(self):
f = BytesIO()
w = BitstreamWriter(f)
# Sequence with every data unit type and fully automatic numbers
stream = Stream(
sequences=[
Sequence(
data_units=[
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.sequence_header
),
sequence_header=SequenceHeader(
parse_parameters=ParseParameters(major_version=3),
video_parameters=SourceParameters(
# Tiny custom frame-size used to reduce test suite
# runtime
frame_size=FrameSize(
custom_dimensions_flag=True,
frame_width=4,
frame_height=4,
)
),
),
),
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture
),
picture_parse=PictureParse(
picture_header=PictureHeader(picture_number=0)
),
),
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.low_delay_picture
),
picture_parse=PictureParse(
picture_header=PictureHeader(picture_number=0)
),
),
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture_fragment
),
fragment_parse=FragmentParse(
fragment_header=FragmentHeader(picture_number=0)
),
),
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture_fragment
),
fragment_parse=FragmentParse(
fragment_header=FragmentHeader(picture_number=0)
),
),
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.padding_data
),
padding=Padding(bytes=b"123"),
),
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.auxiliary_data
),
auxiliary_data=AuxiliaryData(bytes=b"123"),
),
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.end_of_sequence
),
),
]
)
]
)
(
next_parse_offsets_to_autofill,
previous_parse_offsets_to_autofill,
) = autofill_parse_offsets(stream)
with Serialiser(w, stream, vc2_default_values_with_auto) as serdes:
vc2.parse_stream(serdes, State())
w.flush()
offset_before = w.tell()
autofill_parse_offsets_finalize(
w,
serdes.context,
next_parse_offsets_to_autofill,
previous_parse_offsets_to_autofill,
)
assert w.tell() == offset_before
f.seek(0)
r = BitstreamReader(f)
with Deserialiser(r) as serdes:
vc2.parse_stream(serdes, State())
parse_infos = [
data_unit["parse_info"]
for sequence in serdes.context["sequences"]
for data_unit in sequence["data_units"]
]
# Check for start/end offsets being zero
assert parse_infos[0]["previous_parse_offset"] == 0
assert parse_infos[-1]["next_parse_offset"] == 0
# Check for consistency and plusibility of offsets
for pi1, pi2 in zip(parse_infos, parse_infos[1:]):
assert pi1["next_parse_offset"] > 13
assert pi2["previous_parse_offset"] > 13
assert pi1["next_parse_offset"] == pi2["previous_parse_offset"]
def test_doesnt_crash_on_empty_stream(self, stream):
stream_orig = deepcopy(stream)
assert autofill_parse_offsets(stream) == ([], [])
assert stream == stream_orig
def test_works_on_multiple_sequences(self):
f = BytesIO()
w = BitstreamWriter(f)
# Sequence with every data unit type and fully automatic numbers
stream = Stream(
sequences=[
Sequence(
data_units=[
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.padding_data
)
),
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.padding_data
)
),
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.end_of_sequence
)
),
]
),
Sequence(
data_units=[
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.padding_data
)
),
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.padding_data
)
),
DataUnit(
parse_info=ParseInfo(
parse_code=tables.ParseCodes.end_of_sequence
)
),
]
),
]
)
(
next_parse_offsets_to_autofill,
previous_parse_offsets_to_autofill,
) = autofill_parse_offsets(stream)
print(stream)
with Serialiser(w, stream, vc2_default_values_with_auto) as serdes:
vc2.parse_stream(serdes, State())
w.flush()
autofill_parse_offsets_finalize(
w,
serdes.context,
next_parse_offsets_to_autofill,
previous_parse_offsets_to_autofill,
)
f.seek(0)
r = BitstreamReader(f)
with Deserialiser(r) as serdes:
vc2.parse_stream(serdes, State())
parse_infos = [
[data_unit["parse_info"] for data_unit in sequence["data_units"]]
for sequence in serdes.context["sequences"]
]
# Check for start/end offsets being zero
for sequence_pis in parse_infos:
assert sequence_pis[0]["previous_parse_offset"] == 0
assert sequence_pis[-1]["next_parse_offset"] == 0
# Check for offset correctness
for pi1, pi2 in zip(sequence_pis, sequence_pis[1:]):
assert pi1["next_parse_offset"] == 13
assert pi2["previous_parse_offset"] == 13