def color_spec(state, video_parameters):
"""(11.4.10.1)"""
custom_color_spec_flag = read_bool(state)
# (C.3) Check level allows custom color specs
## Begin not in spec
assert_level_constraint(state, "custom_color_spec_flag", custom_color_spec_flag)
## End not in spec
if custom_color_spec_flag:
index = read_uint(state)
# (11.4.10.1) Index should be a supported value
assert_in_enum(index, PresetColorSpecs, BadPresetColorSpec) ## Not in spec
# (C.3) Check level allows the specified preset
assert_level_constraint(state, "color_spec_index", index) ## Not in spec
preset_color_spec(video_parameters, index)
if index == 0:
color_primaries(state, video_parameters)
color_matrix(state, video_parameters)
transfer_function(state, video_parameters)
## Begin not in spec
else:
# (11.2.2) Color spec must be supported by current version
minimum_required_version = preset_color_spec_version_implication(index)
if state["major_version"] < minimum_required_version:
raise PresetColorSpecNotSupportedByVersion(
index, state["major_version"]
)
log_version_lower_bound(state, minimum_required_version)
def transfer_function(state, video_parameters):
"""(11.4.10.4)"""
custom_transfer_function_flag = read_bool(state)
# (C.3) Check level allows custom transfer functions
## Begin not in spec
assert_level_constraint(
state, "custom_transfer_function_flag", custom_transfer_function_flag
)
## End not in spec
if custom_transfer_function_flag:
index = read_uint(state)
# (11.4.10.3) Index should be a supported value
## Begin not in spec
assert_in_enum(index, PresetTransferFunctions, BadPresetTransferFunction)
## End not in spec
# (C.3) Check level allows the specified preset
## Begin not in spec
assert_level_constraint(state, "transfer_function_index", index)
## End not in spec
# (11.2.2) Preset must be supported by current version
## Begin not in spec
minimum_required_version = preset_transfer_function_version_implication(index)
if state["major_version"] < minimum_required_version:
raise PresetTransferFunctionNotSupportedByVersion(
index, state["major_version"]
)
log_version_lower_bound(state, minimum_required_version)
## End not in spec
preset_transfer_function(video_parameters, index)
def scan_format(state, video_parameters):
"""(11.4.5)"""
custom_scan_format_flag = read_bool(state)
# (C.3) Check level allows custom scan formats
## Begin not in spec
assert_level_constraint(state, "custom_scan_format_flag", custom_scan_format_flag)
## End not in spec
if custom_scan_format_flag:
video_parameters["source_sampling"] = read_uint(state)
# (11.4.5) Mode be a known value
## Begin not in spec
assert_in_enum(
video_parameters["source_sampling"],
SourceSamplingModes,
BadSourceSamplingMode,
)
## End not in spec
# (C.3) Check level allows this value
## Begin not in spec
assert_level_constraint(
state,
"source_sampling",
video_parameters["source_sampling"],
)
def color_diff_sampling_format(state, video_parameters):
"""(11.4.4)"""
custom_color_diff_format_flag = read_bool(state)
# (C.3) Check level allows custom color difference sampling
## Begin not in spec
assert_level_constraint(
state, "custom_color_diff_format_flag", custom_color_diff_format_flag
)
## End not in spec
if custom_color_diff_format_flag:
video_parameters["color_diff_format_index"] = read_uint(state)
# (11.4.4) Index shall be a known value
## Begin not in spec
assert_in_enum(
video_parameters["color_diff_format_index"],
ColorDifferenceSamplingFormats,
BadColorDifferenceSamplingFormat,
)
## End not in spec
# (C.3) Check level allows this value
## Begin not in spec
assert_level_constraint(
state,
"color_diff_format_index",
video_parameters["color_diff_format_index"],
)
def frame_size(state, video_parameters):
"""(11.4.3)"""
custom_dimensions_flag = read_bool(state)
# (C.3) Check level allows this value
## Begin not in spec
assert_level_constraint(state, "custom_dimensions_flag", custom_dimensions_flag)
## End not in spec
if custom_dimensions_flag:
video_parameters["frame_width"] = read_uint(state)
# (C.3) Check level allows this value
## Begin not in spec
assert_level_constraint(state, "frame_width", video_parameters["frame_width"])
## End not in spec
video_parameters["frame_height"] = read_uint(state)
# (C.3) Check level allows this value
## Begin not in spec
assert_level_constraint(state, "frame_height", video_parameters["frame_height"])
## End not in spec
# Errata: spec doesn't prevent zero-pixel pictures
#
# (11.4.3) Frames must be at least one pixel wide and tall
## Begin not in spec
if (
video_parameters["frame_width"] == 0
or video_parameters["frame_height"] == 0
):
raise ZeroPixelFrameSize(
video_parameters["frame_width"],
video_parameters["frame_height"],
)
def extended_transform_parameters(state):
"""(12.4.4.1)"""
asym_transform_index_flag = read_bool(state)
# (C.3) Check level allows an asymmetric transform types
## Begin not in spec
assert_level_constraint(state, "asym_transform_index_flag",
asym_transform_index_flag)
## End not in spec
if asym_transform_index_flag:
state["wavelet_index_ho"] = read_uint(state)
# (12.4.4.2) Check wavelet type is supported
## Begin not in spec
assert_in_enum(state["wavelet_index_ho"], WaveletFilters,
BadHOWaveletIndex)
## End not in spec
# (C.3) Check level allows this wavelet type
## Begin not in spec
assert_level_constraint(state, "wavelet_index_ho",
state["wavelet_index_ho"])
## End not in spec
asym_transform_flag = read_bool(state)
# (C.3) Check level allows an asymmetric transform depths
## Begin not in spec
assert_level_constraint(state, "asym_transform_flag", asym_transform_flag)
## End not in spec
if asym_transform_flag:
state["dwt_depth_ho"] = read_uint(state)
# (C.3) Check level allows this wavelet depth
## Begin not in spec
assert_level_constraint(state, "dwt_depth_ho", state["dwt_depth_ho"])
## End not in spec
# (11.2.2) Log increased minimum version requirements if an asymmetric
# transform was used.
## Begin not in spec
minimum_required_version = wavelet_transform_version_implication(
state["wavelet_index"],
state["wavelet_index_ho"],
state["dwt_depth_ho"],
)
log_version_lower_bound(state, minimum_required_version)
def pixel_aspect_ratio(state, video_parameters):
"""(11.4.7)"""
custom_pixel_aspect_ratio_flag = read_bool(state)
# (C.3) Check level allows custom pixel aspect ratio
## Begin not in spec
assert_level_constraint(
state, "custom_pixel_aspect_ratio_flag", custom_pixel_aspect_ratio_flag
)
## End not in spec
if custom_pixel_aspect_ratio_flag:
index = read_uint(state)
# (C.3) Check level allows the specified preset
## Begin not in spec
assert_level_constraint(state, "pixel_aspect_ratio_index", index)
## End not in spec
if index == 0:
video_parameters["pixel_aspect_ratio_numer"] = read_uint(state)
# (C.3) Check level allows the specified numerator
## Begin not in spec
assert_level_constraint(
state,
"pixel_aspect_ratio_numer",
video_parameters["pixel_aspect_ratio_numer"],
)
## End not in spec
video_parameters["pixel_aspect_ratio_denom"] = read_uint(state)
# (C.3) Check level allows the specified denominator
## Begin not in spec
assert_level_constraint(
state,
"pixel_aspect_ratio_denom",
video_parameters["pixel_aspect_ratio_denom"],
)
## End not in spec
# Errata: spec fails to require ratio to be non-zero on either side
#
# (11.4.7) ratio must not contain zeros
## Begin not in spec
if (
video_parameters["pixel_aspect_ratio_numer"] == 0
or video_parameters["pixel_aspect_ratio_denom"] == 0
):
raise PixelAspectRatioContainsZeros(
video_parameters["pixel_aspect_ratio_numer"],
video_parameters["pixel_aspect_ratio_denom"],
)
## End not in spec
else:
# (11.4.7) Pixel aspect ratio preset must be a known value
## Begin not in spec
assert_in_enum(index, PresetPixelAspectRatios, BadPresetPixelAspectRatio)
## End not in spec
preset_pixel_aspect_ratio(video_parameters, index)
def clean_area(state, video_parameters):
"""(11.4.8)"""
custom_clean_area_flag = read_bool(state)
# (C.3) Check level allows custom clean area
## Begin not in spec
assert_level_constraint(state, "custom_clean_area_flag", custom_clean_area_flag)
## End not in spec
if custom_clean_area_flag:
video_parameters["clean_width"] = read_uint(state)
# (C.3) Check level allows this width
## Begin not in spec
assert_level_constraint(state, "clean_width", video_parameters["clean_width"])
## End not in spec
video_parameters["clean_height"] = read_uint(state)
# (C.3) Check level allows this height
## Begin not in spec
assert_level_constraint(state, "clean_height", video_parameters["clean_height"])
## End not in spec
video_parameters["left_offset"] = read_uint(state)
# (C.3) Check level allows this offset
## Begin not in spec
assert_level_constraint(state, "left_offset", video_parameters["left_offset"])
## End not in spec
video_parameters["top_offset"] = read_uint(state)
# (C.3) Check level allows this offset
## Begin not in spec
assert_level_constraint(state, "top_offset", video_parameters["top_offset"])
## End not in spec
# (11.4.8) The clean area is restricted to being within the existing
# picture area
## Begin not in spec
if not (
video_parameters["clean_width"] + video_parameters["left_offset"]
<= video_parameters["frame_width"]
and video_parameters["clean_height"] + video_parameters["top_offset"]
<= video_parameters["frame_height"]
):
raise CleanAreaOutOfRange(
video_parameters["clean_width"],
video_parameters["clean_height"],
video_parameters["left_offset"],
video_parameters["top_offset"],
video_parameters["frame_width"],
video_parameters["frame_height"],
)
def signal_range(state, video_parameters):
"""(11.4.9)"""
custom_signal_range_flag = read_bool(state)
# (C.3) Check level allows custom signal range
## Begin not in spec
assert_level_constraint(state, "custom_signal_range_flag", custom_signal_range_flag)
## End not in spec
if custom_signal_range_flag:
index = read_uint(state)
# (C.3) Check level allows the specified preset
## Begin not in spec
assert_level_constraint(state, "custom_signal_range_index", index)
## End not in spec
if index == 0:
video_parameters["luma_offset"] = read_uint(state)
# (C.3) Check level allows this offset
## Begin not in spec
assert_level_constraint(
state, "luma_offset", video_parameters["luma_offset"]
)
## End not in spec
video_parameters["luma_excursion"] = read_uint(state)
# (C.3) Check level allows this excursion
## Begin not in spec
assert_level_constraint(
state, "luma_excursion", video_parameters["luma_excursion"]
)
## End not in spec
# (11.4.9) Check luma_excursion is valid
#
# Errata: Spec fails to constrain excursions. Excursions *must* be
# >= 1 or the pseudocode behaviour will be undefined.
## Begin not in spec
if video_parameters["luma_excursion"] < 1:
raise BadCustomSignalExcursion(
"luma", video_parameters["luma_excursion"]
)
## End not in spec
video_parameters["color_diff_offset"] = read_uint(state)
# (C.3) Check level allows this offset
## Begin not in spec
assert_level_constraint(
state, "color_diff_offset", video_parameters["color_diff_offset"]
)
## End not in spec
video_parameters["color_diff_excursion"] = read_uint(state)
# (C.3) Check level allows this excursion
## Begin not in spec
assert_level_constraint(
state, "color_diff_excursion", video_parameters["color_diff_excursion"]
)
## End not in spec
# (11.4.9) Check color_diff_excursion is valid
#
# Errata: Spec fails to constrain excursions. Excursions *must* be
# >= 1 or the pseudocode behaviour will be undefined.
## Begin not in spec
if video_parameters["color_diff_excursion"] < 1:
raise BadCustomSignalExcursion(
"color_diff", video_parameters["color_diff_excursion"]
)
## End not in spec
else:
# (11.4.9) Signal range preset must be a known value
## Begin not in spec
assert_in_enum(index, PresetSignalRanges, BadPresetSignalRange)
## End not in spec
# (11.2.2) Signal range preset must be supported by current version
## Begin not in spec
minimum_required_version = preset_signal_range_version_implication(index)
if state["major_version"] < minimum_required_version:
raise PresetSignalRangeNotSupportedByVersion(
index, state["major_version"]
)
log_version_lower_bound(state, minimum_required_version)
## End not in spec
preset_signal_range(video_parameters, index)
def frame_rate(state, video_parameters):
"""(11.4.6)"""
custom_frame_rate_flag = read_bool(state)
# (C.3) Check level allows custom frame rates
## Begin not in spec
assert_level_constraint(state, "custom_frame_rate_flag", custom_frame_rate_flag)
## End not in spec
if custom_frame_rate_flag:
index = read_uint(state)
# (C.3) Check level allows the specified preset
assert_level_constraint(state, "frame_rate_index", index) ## Not in spec
if index == 0:
video_parameters["frame_rate_numer"] = read_uint(state)
# (C.3) Check level allows the specified numerator
## Begin not in spec
assert_level_constraint(
state,
"frame_rate_numer",
video_parameters["frame_rate_numer"],
)
## End not in spec
video_parameters["frame_rate_denom"] = read_uint(state)
# (C.3) Check level allows the specified denominator
## Begin not in spec
assert_level_constraint(
state,
"frame_rate_denom",
video_parameters["frame_rate_denom"],
)
## End not in spec
# Errata: spec doesn't prevent divide-by-zero in custom frame rate
# fractions.
#
# (11.4.6) frame_rate_denom must not be zero (i.e. a divide by zero)
## Begin not in spec
if video_parameters["frame_rate_denom"] == 0:
raise FrameRateHasZeroDenominator(video_parameters["frame_rate_numer"])
## End not in spec
# Errata: spec doesn't prevent 0 fps
#
# (11.4.6) frame_rate_numer must not be zero (i.e. 0 fps)
## Begin not in spec
if video_parameters["frame_rate_numer"] == 0:
raise FrameRateHasZeroNumerator(video_parameters["frame_rate_denom"])
## End not in spec
else:
# (11.4.6) Frame rate preset must be a known value
## Begin not in spec
assert_in_enum(index, PresetFrameRates, BadPresetFrameRateIndex)
## End not in spec
# (11.2.2) Frame rate preset must be supported by current version
## Begin not in spec
minimum_required_version = preset_frame_rate_version_implication(index)
if state["major_version"] < minimum_required_version:
raise PresetFrameRateNotSupportedByVersion(
index, state["major_version"]
)
log_version_lower_bound(state, minimum_required_version)
## End not in spec
preset_frame_rate(video_parameters, index)
def quant_matrix(state):
"""(12.4.5.3)"""
custom_quant_matrix = read_bool(state)
# (C.3) Check level allows use of custom quantisation matrices
## Begin not in spec
assert_level_constraint(state, "custom_quant_matrix", custom_quant_matrix)
## End not in spec
if custom_quant_matrix:
# (C.3) Check that quantisation matrix values are in the level-defined
# range
## Begin not in spec
allowed_values = allowed_values_for(
LEVEL_CONSTRAINTS,
"quant_matrix_values",
state["_level_constrained_values"],
)
def check(quant_matrix_value):
assert_in(
quant_matrix_value,
allowed_values,
QuantisationMatrixValueNotAllowedInLevel,
state["_level_constrained_values"],
)
## End not in spec
# NB: For historical reasons, we use a dict not an array in this
# implementation.
### state["quant_matrix"] = new_array(state["dwt_depth_ho"] + state["dwt_depth"] + 1)
state["quant_matrix"] = {} ## Not in spec
if state["dwt_depth_ho"] == 0:
state["quant_matrix"][0] = {}
state["quant_matrix"][0]["LL"] = read_uint(state)
check(state["quant_matrix"][0]["LL"]) ## Not in spec
else:
state["quant_matrix"][0] = {}
state["quant_matrix"][0]["L"] = read_uint(state)
check(state["quant_matrix"][0]["L"]) ## Not in spec
for level in range(1, state["dwt_depth_ho"] + 1):
state["quant_matrix"][level] = {}
state["quant_matrix"][level]["H"] = read_uint(state)
check(state["quant_matrix"][level]["H"]) ## Not in spec
for level in range(state["dwt_depth_ho"] + 1,
state["dwt_depth_ho"] + state["dwt_depth"] + 1):
state["quant_matrix"][level] = {}
state["quant_matrix"][level]["HL"] = read_uint(state)
check(state["quant_matrix"][level]["HL"]) ## Not in spec
state["quant_matrix"][level]["LH"] = read_uint(state)
check(state["quant_matrix"][level]["LH"]) ## Not in spec
state["quant_matrix"][level]["HH"] = read_uint(state)
check(state["quant_matrix"][level]["HH"]) ## Not in spec
else:
# (12.4.5.3) If no custom quantisation matrix has been specified, a
# default table must be available
## Begin not in spec
configuration = (
state["wavelet_index"],
state["wavelet_index_ho"],
state["dwt_depth"],
state["dwt_depth_ho"],
)
if configuration not in QUANTISATION_MATRICES:
raise NoQuantisationMatrixAvailable(*configuration)
## End not in spec
set_quant_matrix(state)