def test_profile_version_restriction(self):
# A sequence with no pictures but (incorrectly) major_version 1 and
# profile high quality.
seq = bitstream.Sequence(data_units=[
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.sequence_header, ),
sequence_header=bitstream.SequenceHeader(
parse_parameters=bitstream.ParseParameters(
major_version=1,
profile=tables.Profiles.high_quality,
),
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
# Don't waste time on full-sized frames
custom_dimensions_flag=True,
frame_width=4,
frame_height=4,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
clean_width=4,
clean_height=4,
),
),
),
),
bitstream.DataUnit(parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.end_of_sequence, ), ),
])
populate_parse_offsets(seq)
state = bytes_to_state(serialise_to_bytes(seq))
with pytest.raises(decoder.ProfileNotSupportedByVersion):
decoder.parse_stream(state)
def test_whole_picture(parse_code):
# A sanity check which runs picture decoding for whole pictures and makes
# sure nothing crashes
# Serialise a sample stream
sh = bitstream.SequenceHeader(
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
# Don't waste time on full-sized frames
custom_dimensions_flag=True,
frame_width=4,
frame_height=4,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
clean_width=4,
clean_height=4,
),
), )
serialisation_state = State()
sh_bytes = serialise_to_bytes(sh, serialisation_state)
serialisation_state["parse_code"] = parse_code
pic_bytes = serialise_to_bytes(bitstream.PictureParse(),
serialisation_state)
# Check it is parsed without failiures
state = bytes_to_state(sh_bytes + pic_bytes)
state["_num_pictures_in_sequence"] = 0
decoder.sequence_header(state)
state["parse_code"] = parse_code
decoder.picture_parse(state)
def test_parse_code_version_restriction(self):
# A sequence with 1 HQ picture fragment but (incorrectly) major_version 2
seq = bitstream.Sequence(data_units=[
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.sequence_header, ),
sequence_header=bitstream.SequenceHeader(
parse_parameters=bitstream.ParseParameters(major_version=2,
),
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
# Don't waste time on full-sized frames
custom_dimensions_flag=True,
frame_width=4,
frame_height=4,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
clean_width=4,
clean_height=4,
),
),
),
),
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture_fragment,
),
fragment_parse=bitstream.FragmentParse(
fragment_header=bitstream.FragmentHeader(
fragment_slice_count=0, ),
transform_parameters=bitstream.TransformParameters(
slice_parameters=bitstream.SliceParameters(
slices_x=1,
slices_y=1,
), ),
),
),
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture_fragment,
),
fragment_parse=bitstream.FragmentParse(
fragment_header=bitstream.FragmentHeader(
fragment_slice_count=1, ), ),
),
bitstream.DataUnit(parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.end_of_sequence, ), ),
])
populate_parse_offsets(seq)
state = bytes_to_state(serialise_to_bytes(seq))
with pytest.raises(decoder.ParseCodeNotSupportedByVersion):
decoder.parse_stream(state)
def test_picture_dimensions_must_be_multiple_of_frame_dimensions(
self,
frame_width,
frame_height,
exp_luma_width,
exp_luma_height,
exp_color_diff_width,
exp_color_diff_height,
exp_error,
):
state = bytes_to_state(
serialise_to_bytes(
bitstream.SequenceHeader(
picture_coding_mode=tables.PictureCodingModes.
pictures_are_fields,
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
custom_dimensions_flag=True,
frame_width=frame_width,
frame_height=frame_height,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
clean_width=frame_width,
clean_height=frame_height,
),
color_diff_sampling_format=bitstream.
ColorDiffSamplingFormat(
custom_color_diff_format_flag=True,
color_diff_format_index=tables.
ColorDifferenceSamplingFormats.
color_4_2_0, # noqa: E501
),
),
)))
if exp_error:
with pytest.raises(
decoder.PictureDimensionsNotMultipleOfFrameDimensions
) as exc_info:
decoder.sequence_header(state)
assert exc_info.value.luma_width == exp_luma_width
assert exc_info.value.luma_height == exp_luma_height
assert exc_info.value.color_diff_width == exp_color_diff_width
assert exc_info.value.color_diff_height == exp_color_diff_height
assert exc_info.value.frame_width == frame_width
assert exc_info.value.frame_height == frame_height
else:
decoder.sequence_header(state)
assert state["luma_width"] == exp_luma_width
assert state["luma_height"] == exp_luma_height
assert state["color_diff_width"] == exp_color_diff_width
assert state["color_diff_height"] == exp_color_diff_height
def test_minimal_major_version_requirement(
self,
num_pictures,
major_version,
expected_major_version,
exp_fail,
):
# A sequence with 1 (or zero) HQ pictures
seq = bitstream.Sequence(data_units=[
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.sequence_header, ),
sequence_header=bitstream.SequenceHeader(
parse_parameters=bitstream.ParseParameters(
major_version=major_version, ),
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
# Don't waste time on full-sized frames
custom_dimensions_flag=True,
frame_width=4,
frame_height=4,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
clean_width=4,
clean_height=4,
),
),
),
),
] + [
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture, ),
picture_parse=bitstream.PictureParse(
picture_header=bitstream.PictureHeader(picture_number=n,
), ),
) for n in range(num_pictures)
] + [
bitstream.DataUnit(parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.end_of_sequence, ), ),
])
populate_parse_offsets(seq)
state = bytes_to_state(serialise_to_bytes(seq))
if exp_fail:
with pytest.raises(decoder.MajorVersionTooHigh):
decoder.parse_stream(state)
else:
decoder.parse_stream(state)
assert state["_expected_major_version"] == expected_major_version
def test_odd_number_of_fields_disallowed(self, picture_coding_mode,
num_pictures, exp_fail):
# A sequence with num_pictures HQ pictures
seq = bitstream.Sequence(data_units=[
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.sequence_header, ),
sequence_header=bitstream.SequenceHeader(
picture_coding_mode=picture_coding_mode,
parse_parameters=bitstream.ParseParameters(
major_version=2),
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
# Don't waste time on full-sized frames
custom_dimensions_flag=True,
frame_width=4,
frame_height=4,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
clean_width=4,
clean_height=4,
),
),
),
),
] + [
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture, ),
picture_parse=bitstream.PictureParse(
picture_header=bitstream.PictureHeader(picture_number=n,
), ),
) for n in range(num_pictures)
] + [
bitstream.DataUnit(parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.end_of_sequence, ), ),
])
populate_parse_offsets(seq)
state = bytes_to_state(serialise_to_bytes(seq))
if exp_fail:
with pytest.raises(
decoder.OddNumberOfFieldsInSequence) as exc_info:
decoder.parse_stream(state)
assert exc_info.value.num_fields_in_sequence == num_pictures
else:
decoder.parse_stream(state)
def valid_bitstream(self, filename):
"""
Creates a valid bitstream in the file whose name is returned by this
fixture. This bitstream consists of two small pictures.
A minimal bitstream with a pair of 4x4 pixel 4:2:0 8-bit pictures with
picture numbers 100 and 101.
"""
with open(filename, "wb") as f:
w = bitstream.BitstreamWriter(f)
seq = bitstream.Sequence(
data_units=[
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.sequence_header,
next_parse_offset=19,
),
sequence_header=bitstream.SequenceHeader(
parse_parameters=bitstream.ParseParameters(
major_version=2,
),
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
custom_dimensions_flag=True,
frame_width=4,
frame_height=4,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
left_offset=0,
top_offset=0,
clean_width=4,
clean_height=4,
),
color_diff_sampling_format=bitstream.ColorDiffSamplingFormat( # noqa: E501
custom_color_diff_format_flag=True,
color_diff_format_index=tables.ColorDifferenceSamplingFormats.color_4_2_0, # noqa: E501
),
),
picture_coding_mode=tables.PictureCodingModes.pictures_are_frames, # noqa: E501
),
),
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture,
next_parse_offset=24,
previous_parse_offset=19,
),
picture_parse=bitstream.PictureParse(
picture_header=bitstream.PictureHeader(
picture_number=100,
),
),
),
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture,
next_parse_offset=24,
previous_parse_offset=24,
),
picture_parse=bitstream.PictureParse(
picture_header=bitstream.PictureHeader(
picture_number=101,
),
),
),
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.end_of_sequence,
previous_parse_offset=24,
)
),
]
)
with bitstream.Serialiser(w, seq, bitstream.vc2_default_values) as ser:
bitstream.parse_sequence(ser, State())
w.flush()
return filename
def test_whole_picture(parse_code, fragment_slice_counts):
# A sanity check which runs fragmented picture decoding for whole pictures
# and makes sure nothing crashes
# Serialise a sample stream
sh = bitstream.SequenceHeader(
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
# Don't waste time on full-sized frames
custom_dimensions_flag=True,
frame_width=8,
frame_height=8,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
clean_width=8,
clean_height=8,
),
), )
serialisation_state = State()
sh_bytes = serialise_to_bytes(sh, serialisation_state)
serialisation_state["parse_code"] = parse_code
frag_bytes = b""
# Add the first (header) fragment in the picture
frag_bytes += serialise_to_bytes(
bitstream.FragmentParse(
fragment_header=bitstream.FragmentHeader(fragment_slice_count=0, ),
transform_parameters=bitstream.TransformParameters(
slice_parameters=bitstream.SliceParameters(
slices_x=3,
slices_y=2,
)),
),
serialisation_state,
)
# Add the slice-containing fragments
num_slices = 0
for fragment_slice_count in fragment_slice_counts:
x = num_slices % 3
y = num_slices // 3
num_slices += fragment_slice_count
frag_bytes += serialise_to_bytes(
bitstream.FragmentParse(fragment_header=bitstream.FragmentHeader(
fragment_slice_count=fragment_slice_count,
fragment_x_offset=x,
fragment_y_offset=y,
), ),
serialisation_state,
)
# Check it is parsed without failiures
state = bytes_to_state(sh_bytes + frag_bytes)
state["_num_pictures_in_sequence"] = 0
state["_fragment_slices_remaining"] = 0
decoder.sequence_header(state)
# Parse header fragment
decoder.byte_align(state)
state["parse_code"] = parse_code
decoder.fragment_parse(state)
# Parse slice-containing fragments
num_slices = 0
for fragment_slice_count in fragment_slice_counts:
assert state["fragmented_picture_done"] is False
decoder.byte_align(state)
state["parse_code"] = parse_code
decoder.fragment_parse(state)
num_slices += fragment_slice_count
assert state["fragment_slices_received"] == num_slices
assert state["_fragment_slices_remaining"] == 6 - num_slices
assert state["fragmented_picture_done"] is True
def test_level_constraints():
# Simply check that all constrainted level values get asserted. We check
# this by making sure assert_level_constraint has added the relevant values
# to # state["_level_constrained_values"].
state = bytes_to_state(
serialise_to_bytes(
bitstream.SequenceHeader(
base_video_format=tables.BaseVideoFormats.custom_format,
picture_coding_mode=tables.PictureCodingModes.
pictures_are_frames,
parse_parameters=bitstream.ParseParameters(
level=tables.Levels.unconstrained,
profile=tables.Profiles.high_quality,
major_version=3,
minor_version=0,
),
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
custom_dimensions_flag=True,
frame_width=1280,
frame_height=1080,
),
color_diff_sampling_format=bitstream.
ColorDiffSamplingFormat(
custom_color_diff_format_flag=True,
color_diff_format_index=tables.
ColorDifferenceSamplingFormats.color_4_4_4,
),
scan_format=bitstream.ScanFormat(
custom_scan_format_flag=True,
source_sampling=tables.SourceSamplingModes.progressive,
),
frame_rate=bitstream.FrameRate(
custom_frame_rate_flag=True,
index=0,
frame_rate_numer=25,
frame_rate_denom=1,
),
pixel_aspect_ratio=bitstream.PixelAspectRatio(
custom_pixel_aspect_ratio_flag=True,
index=0,
pixel_aspect_ratio_numer=1,
pixel_aspect_ratio_denom=1,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
clean_width=1,
clean_height=2,
left_offset=3,
top_offset=4,
),
signal_range=bitstream.SignalRange(
custom_signal_range_flag=True,
index=0,
luma_offset=1,
luma_excursion=2,
color_diff_offset=3,
color_diff_excursion=4,
),
color_spec=bitstream.ColorSpec(
custom_color_spec_flag=True,
index=0,
color_primaries=bitstream.ColorPrimaries(
custom_color_primaries_flag=True,
index=tables.PresetColorPrimaries.uhdtv,
),
color_matrix=bitstream.ColorMatrix(
custom_color_matrix_flag=True,
index=tables.PresetColorMatrices.uhdtv,
),
transfer_function=bitstream.TransferFunction(
custom_transfer_function_flag=True,
index=tables.PresetTransferFunctions.
hybrid_log_gamma,
),
),
),
)))
decoder.sequence_header(state)
assert state["_level_constrained_values"] == {
# sequence_header
"base_video_format": tables.BaseVideoFormats.custom_format,
"picture_coding_mode": tables.PictureCodingModes.pictures_are_frames,
# parse_parameters
"level": tables.Levels.unconstrained,
"profile": tables.Profiles.high_quality,
"major_version": 3,
"minor_version": 0,
# frame_size
"custom_dimensions_flag": True,
"frame_width": 1280,
"frame_height": 1080,
# color_diff_sampling_format
"custom_color_diff_format_flag": True,
"color_diff_format_index":
tables.ColorDifferenceSamplingFormats.color_4_4_4,
# scan_format
"custom_scan_format_flag": True,
"source_sampling": tables.SourceSamplingModes.progressive,
# frame_rate
"custom_frame_rate_flag": True,
"frame_rate_index": 0,
"frame_rate_numer": 25,
"frame_rate_denom": 1,
# pixel_aspect_ratio
"custom_pixel_aspect_ratio_flag": True,
"pixel_aspect_ratio_index": 0,
"pixel_aspect_ratio_numer": 1,
"pixel_aspect_ratio_denom": 1,
# clean_area
"custom_clean_area_flag": True,
"clean_width": 1,
"clean_height": 2,
"left_offset": 3,
"top_offset": 4,
# signal_range
"custom_signal_range_flag": True,
"custom_signal_range_index": 0,
"luma_offset": 1,
"luma_excursion": 2,
"color_diff_offset": 3,
"color_diff_excursion": 4,
# color_spec
"custom_color_spec_flag": True,
"color_spec_index": 0,
# color_primaries
"custom_color_primaries_flag": True,
"color_primaries_index": tables.PresetColorPrimaries.uhdtv,
# color_matrix
"custom_color_matrix_flag": True,
"color_matrix_index": tables.PresetColorMatrices.uhdtv,
# transfer_function
"custom_transfer_function_flag": True,
"transfer_function_index":
tables.PresetTransferFunctions.hybrid_log_gamma,
}
def test_output_picture(self):
# This test adds a callback for output_picture and makes sure that both
# fragments and pictures call it correctly (and that sanity-checks very
# loosely that decoding etc. is happening). Finally, it also checks
# that two concatenated sequences are read one after another.
# A sequence with a HQ picture followed by a HQ fragment (both all
# zeros)
seq1 = bitstream.Sequence(data_units=[
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.sequence_header, ),
sequence_header=bitstream.SequenceHeader(
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
# Don't waste time on full-sized frames
custom_dimensions_flag=True,
frame_width=4,
frame_height=2,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
clean_width=4,
clean_height=2,
),
color_diff_sampling_format=bitstream.
ColorDiffSamplingFormat(
custom_color_diff_format_flag=True,
color_diff_format_index=tables.
ColorDifferenceSamplingFormats.
color_4_2_2, # noqa: E501
),
# Output values will be treated as 8-bit (and thus all
# decode to 128)
signal_range=bitstream.SignalRange(
custom_signal_range_flag=True,
index=tables.PresetSignalRanges.
video_8bit_full_range,
),
),
picture_coding_mode=tables.PictureCodingModes.
pictures_are_frames,
),
),
# A HQ picture
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture, ),
picture_parse=bitstream.PictureParse(
picture_header=bitstream.PictureHeader(picture_number=10,
), ),
),
# A fragmented HQ picture (sent over two fragments to ensure the
# callback only fires after a whole picture arrives)
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture_fragment,
),
fragment_parse=bitstream.FragmentParse(
fragment_header=bitstream.FragmentHeader(
picture_number=11,
fragment_slice_count=0,
),
transform_parameters=bitstream.TransformParameters(
slice_parameters=bitstream.SliceParameters(
slices_x=2,
slices_y=1,
), ),
),
),
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture_fragment,
),
fragment_parse=bitstream.FragmentParse(
fragment_header=bitstream.FragmentHeader(
picture_number=11,
fragment_slice_count=1,
fragment_x_offset=0,
fragment_y_offset=0,
), ),
),
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture_fragment,
),
fragment_parse=bitstream.FragmentParse(
fragment_header=bitstream.FragmentHeader(
picture_number=11,
fragment_slice_count=1,
fragment_x_offset=1,
fragment_y_offset=0,
), ),
),
bitstream.DataUnit(parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.end_of_sequence, ), ),
])
# Another (HQ) picture in a separate sequence
seq2 = bitstream.Sequence(data_units=[
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.sequence_header, ),
sequence_header=bitstream.SequenceHeader(
parse_parameters=bitstream.ParseParameters(
major_version=2),
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
# Don't waste time on full-sized frames
custom_dimensions_flag=True,
frame_width=4,
frame_height=2,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
clean_width=4,
clean_height=2,
),
color_diff_sampling_format=bitstream.
ColorDiffSamplingFormat(
custom_color_diff_format_flag=True,
color_diff_format_index=tables.
ColorDifferenceSamplingFormats.
color_4_2_2, # noqa: E501
),
# Output values will be treated as 8-bit (and thus all
# decode to 128)
signal_range=bitstream.SignalRange(
custom_signal_range_flag=True,
index=tables.PresetSignalRanges.
video_8bit_full_range,
),
),
picture_coding_mode=tables.PictureCodingModes.
pictures_are_frames,
),
),
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture, ),
picture_parse=bitstream.PictureParse(
picture_header=bitstream.PictureHeader(
picture_number=12), ),
),
bitstream.DataUnit(parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.end_of_sequence, ), ),
])
populate_parse_offsets(seq1)
populate_parse_offsets(seq2)
state = bytes_to_state(
serialise_to_bytes(seq1) + serialise_to_bytes(seq2))
state["_output_picture_callback"] = Mock()
decoder.parse_stream(state)
assert state["_output_picture_callback"].call_count == 3
for i, (args, kwargs) in enumerate(
state["_output_picture_callback"].call_args_list):
assert kwargs == {}
# Should get a 4x2 mid-gray frame with 4:2:2 color difference sampling
assert args[0] == {
"pic_num": 10 + i,
"Y": [[128, 128, 128, 128], [128, 128, 128, 128]],
"C1": [[128, 128], [128, 128]],
"C2": [[128, 128], [128, 128]],
}
# Just sanity check the second argument looks like a set of video parameters
assert args[1]["frame_width"] == 4
assert args[1]["frame_height"] == 2
assert args[1]["luma_offset"] == 0
assert args[1]["luma_offset"] == 0
assert args[1]["luma_excursion"] == 255
assert args[1]["color_diff_offset"] == 128
assert args[1]["color_diff_excursion"] == 255
# And the picture coding mode too...
assert args[2] == tables.PictureCodingModes.pictures_are_frames
def test_picture_and_incomplete_fragment_interleaving_disallowed(
self, num_slices_to_send, exp_fail):
# A sequence with a 3x2 slice picture fragment with num_slices_to_send slices in
# it followed by an HQ picture
seq = bitstream.Sequence(data_units=[
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.sequence_header, ),
sequence_header=bitstream.SequenceHeader(
video_parameters=bitstream.SourceParameters(
frame_size=bitstream.FrameSize(
# Don't waste time on full-sized pictures
custom_dimensions_flag=True,
frame_width=8,
frame_height=8,
),
clean_area=bitstream.CleanArea(
custom_clean_area_flag=True,
clean_width=8,
clean_height=8,
),
), ),
),
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture_fragment,
),
fragment_parse=bitstream.FragmentParse(
fragment_header=bitstream.FragmentHeader(
picture_number=0,
fragment_slice_count=0,
),
transform_parameters=bitstream.TransformParameters(
slice_parameters=bitstream.SliceParameters(
slices_x=3,
slices_y=2,
), ),
),
),
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture_fragment,
),
fragment_parse=bitstream.FragmentParse(
fragment_header=bitstream.FragmentHeader(
picture_number=0,
fragment_slice_count=num_slices_to_send,
), ),
),
bitstream.DataUnit(
parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.high_quality_picture, ),
picture_parse=bitstream.PictureParse(
picture_header=bitstream.PictureHeader(picture_number=1,
), ),
),
bitstream.DataUnit(parse_info=bitstream.ParseInfo(
parse_code=tables.ParseCodes.end_of_sequence, ), ),
])
# Don't include second (non-header) fragment if sending no slices
if num_slices_to_send == 0:
del seq["data_units"][2]
populate_parse_offsets(seq)
state = bytes_to_state(serialise_to_bytes(seq))
if exp_fail:
with pytest.raises(decoder.PictureInterleavedWithFragmentedPicture
) as exc_info:
decoder.parse_stream(state)
first_fragment_offset = (
seq["data_units"][0]["parse_info"]["next_parse_offset"] +
tables.PARSE_INFO_HEADER_BYTES)
assert exc_info.value.initial_fragment_offset == (
first_fragment_offset, 7)
picture_offset = (
sum(seq["data_units"][i]["parse_info"]["next_parse_offset"]
for i in range(len(seq["data_units"]) - 2)) +
tables.PARSE_INFO_HEADER_BYTES)
assert exc_info.value.this_offset == (picture_offset, 7)
assert exc_info.value.fragment_slices_received == num_slices_to_send
assert exc_info.value.fragment_slices_remaining == 6 - num_slices_to_send
else:
decoder.parse_stream(state)