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Removed box_is_XL parameter. #212

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We only get around a 1% performance increase, which is not worth the
increased complexitiy.
This commit is contained in:
jevans 2014-04-06 10:51:50 -04:00
commit 96db5e1a6a
1 changed files with 46 additions and 164 deletions
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210
glymur/jp2box.py
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@ -160,7 +160,7 @@ class Jp2kBox(object):
fptr.write(struct.pack('>I', end_pos - orig_pos))
fptr.seek(end_pos)
def _parse_this_box(self, fptr, box_id, start, num_bytes, box_is_XL):
def _parse_this_box(self, fptr, box_id, start, num_bytes):
"""Parse the current box.
Parameters
@ -172,10 +172,7 @@ class Jp2kBox(object):
4-letter identifier for the current box.
start, num_bytes : int
Byte offset and length of the current box.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
box : Jp2kBox
@ -195,7 +192,7 @@ class Jp2kBox(object):
return box
try:
box = parser(fptr, start, num_bytes, box_is_XL=box_is_XL)
box = parser(fptr, start, num_bytes)
except ValueError as err:
msg = "Encountered an unrecoverable ValueError while parsing a {0} "
msg += "box at byte offset {1}. The original error message was "
@ -236,7 +233,6 @@ class Jp2kBox(object):
warnings.warn(msg)
return superbox
box_is_XL = False
(box_length, box_id) = struct.unpack('>I4s', read_buffer)
if box_length == 0:
# The length of the box is presumed to last until the end of
@ -247,14 +243,12 @@ class Jp2kBox(object):
# The length of the box is in the XL field, a 64-bit value.
read_buffer = fptr.read(8)
num_bytes, = struct.unpack('>Q', read_buffer)
box_is_XL = True
else:
# The box_length value really is the length of the box!
num_bytes = box_length
box = self._parse_this_box(fptr, box_id, start, num_bytes,
box_is_XL)
box = self._parse_this_box(fptr, box_id, start, num_bytes)
superbox.append(box)
@ -410,7 +404,7 @@ class ColourSpecificationBox(Jp2kBox):
fptr.write(read_buffer)
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse JPEG 2000 color specification box.
Parameters
@ -421,16 +415,12 @@ class ColourSpecificationBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
ColourSpecificationBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
# Read the brand, minor version.
(method, precedence, approximation) = struct.unpack_from('>BBB',
@ -666,7 +656,7 @@ class ChannelDefinitionBox(Jp2kBox):
self.association[j]))
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse component definition box.
Parameters
@ -677,16 +667,12 @@ class ChannelDefinitionBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
ComponentDefinitionBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
# Read the number of components.
@ -740,7 +726,7 @@ class CodestreamHeaderBox(Jp2kBox):
self._write_superbox(fptr, b'jpch')
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse codestream header box.
Parameters
@ -751,10 +737,6 @@ class CodestreamHeaderBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -813,7 +795,7 @@ class ColourGroupBox(Jp2kBox):
self._write_superbox(fptr, b'cgrp')
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse colour group box.
Parameters
@ -824,10 +806,6 @@ class ColourGroupBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -880,7 +858,7 @@ class CompositingLayerHeaderBox(Jp2kBox):
self._write_superbox(fptr, b'jplh')
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse compositing layer header box.
Parameters
@ -891,10 +869,6 @@ class CompositingLayerHeaderBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -975,7 +949,7 @@ class ComponentMappingBox(Jp2kBox):
fptr.write(write_buffer)
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse component mapping box.
Parameters
@ -986,16 +960,12 @@ class ComponentMappingBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
ComponentMappingBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
num_components = int(num_bytes/4)
read_buffer = fptr.read(num_bytes)
@ -1049,7 +1019,7 @@ class ContiguousCodestreamBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset=0, length=0, box_is_XL=False):
def parse(cls, fptr, offset=0, length=0):
"""Parse a codestream box.
Parameters
@ -1060,10 +1030,6 @@ class ContiguousCodestreamBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -1151,7 +1117,7 @@ class DataReferenceBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse data reference box.
Parameters
@ -1162,16 +1128,12 @@ class DataReferenceBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
DataReferenceBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
# Read the number of data references
@ -1281,7 +1243,7 @@ class FileTypeBox(Jp2kBox):
fptr.write(item.encode())
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse JPEG 2000 file type box.
Parameters
@ -1292,16 +1254,12 @@ class FileTypeBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
FileTypeBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
# Extract the brand, minor version.
(brand, minor_version) = struct.unpack_from('>4sI', read_buffer, 0)
@ -1398,7 +1356,7 @@ class FragmentListBox(Jp2kBox):
fptr.write(write_buffer)
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse JPX free box.
Parameters
@ -1409,16 +1367,12 @@ class FragmentListBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
FragmentListBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
num_fragments, = struct.unpack_from('>H', read_buffer, offset=0)
@ -1461,7 +1415,7 @@ class FragmentTableBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse JPX fragment table superbox box.
Parameters
@ -1472,10 +1426,6 @@ class FragmentTableBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -1536,7 +1486,7 @@ class FreeBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse JPX free box.
Parameters
@ -1547,10 +1497,6 @@ class FreeBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -1664,7 +1610,7 @@ class ImageHeaderBox(Jp2kBox):
fptr.write(read_buffer)
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse JPEG 2000 image header box.
Parameters
@ -1675,10 +1621,6 @@ class ImageHeaderBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -1736,7 +1678,7 @@ class AssociationBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse association box.
Parameters
@ -1747,10 +1689,6 @@ class AssociationBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -1806,7 +1744,7 @@ class JP2HeaderBox(Jp2kBox):
self._write_superbox(fptr, b'jp2h')
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse JPEG 2000 header box.
Parameters
@ -1817,10 +1755,6 @@ class JP2HeaderBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -1878,7 +1812,7 @@ class JPEG2000SignatureBox(Jp2kBox):
fptr.write(struct.pack('>BBBB', *self.signature))
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse JPEG 2000 signature box.
Parameters
@ -1889,10 +1823,6 @@ class JPEG2000SignatureBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -2000,7 +1930,7 @@ class PaletteBox(Jp2kBox):
fptr.write(write_buffer)
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse palette box.
Parameters
@ -2011,16 +1941,12 @@ class PaletteBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
PaletteBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
nrows, ncols = struct.unpack_from('>HB', read_buffer, offset=0)
@ -2232,7 +2158,7 @@ class ReaderRequirementsBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse reader requirements box.
Parameters
@ -2243,16 +2169,12 @@ class ReaderRequirementsBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
ReaderRequirementsBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
mask_length, = struct.unpack_from('>B', read_buffer, offset=0)
@ -2446,7 +2368,7 @@ class ResolutionBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse Resolution box.
Parameters
@ -2457,10 +2379,6 @@ class ResolutionBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -2514,7 +2432,7 @@ class CaptureResolutionBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse CaptureResolutionBox.
Parameters
@ -2525,10 +2443,6 @@ class CaptureResolutionBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -2581,7 +2495,7 @@ class DisplayResolutionBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse display resolution box.
Parameters
@ -2592,10 +2506,6 @@ class DisplayResolutionBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -2653,7 +2563,7 @@ class LabelBox(Jp2kBox):
fptr.write(self.label.encode())
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse Label box.
Parameters
@ -2664,16 +2574,12 @@ class LabelBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
LabelBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
label = read_buffer.decode('utf-8')
return cls(label, length=length, offset=offset)
@ -2728,7 +2634,7 @@ class NumberListBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse number list box.
Parameters
@ -2739,16 +2645,12 @@ class NumberListBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
LabelBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
raw_data = fptr.read(num_bytes)
num_associations = int(len(raw_data) / 4)
lst = struct.unpack('>' + 'I' * num_associations, raw_data)
@ -2836,7 +2738,7 @@ class XMLBox(Jp2kBox):
fptr.write(read_buffer)
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse XML box.
Parameters
@ -2847,16 +2749,12 @@ class XMLBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
XMLBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
try:
text = read_buffer.decode('utf-8')
@ -2940,7 +2838,7 @@ class UUIDListBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse UUIDList box.
Parameters
@ -2951,16 +2849,12 @@ class UUIDListBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
UUIDListBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
num_uuids, = struct.unpack_from('>H', read_buffer)
@ -3004,7 +2898,7 @@ class UUIDInfoBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse UUIDInfo super box.
Parameters
@ -3015,10 +2909,6 @@ class UUIDInfoBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
@ -3101,7 +2991,7 @@ class DataEntryURLBox(Jp2kBox):
return msg
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse data entry URL box.
Parameters
@ -3112,16 +3002,12 @@ class DataEntryURLBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
DataEntryURLbox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
data = struct.unpack_from('>BBBB', read_buffer)
version = data[0]
@ -3278,7 +3164,7 @@ class UUIDBox(Jp2kBox):
fptr.write(self.raw_data)
@classmethod
def parse(cls, fptr, offset, length, box_is_XL=False):
def parse(cls, fptr, offset, length):
"""Parse UUID box.
Parameters
@ -3289,16 +3175,12 @@ class UUIDBox(Jp2kBox):
Start position of box in bytes.
length : int
Length of the box in bytes.
box_is_XL : bool
True if the box has an XL field. In this case, the start of the
box is 16 bytes behind the start of the box payload instead of being
8 bytes behind.
Returns
-------
UUIDBox instance
"""
num_bytes = length - 16 if box_is_XL else length - 8
num_bytes = offset + length - fptr.tell()
read_buffer = fptr.read(num_bytes)
the_uuid = uuid.UUID(bytes=read_buffer[0:16])
return cls(the_uuid, read_buffer[16:], length=length, offset=offset)