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# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
# The source was png.ksy from here - https://github.com/kaitai-io/kaitai_struct_formats/blob/562154250bea0081fed4e232751b934bc270a0c7/image/gif.ksy
import array
import struct
import zlib
from enum import Enum
from kaitaistruct import KaitaiStruct, KaitaiStream, BytesIO
class Gif(KaitaiStruct):
class BlockType(Enum):
extension = 33
local_image_descriptor = 44
end_of_file = 59
class ExtensionLabel(Enum):
graphic_control = 249
comment = 254
application = 255
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.header = self._root.Header(self._io, self, self._root)
self.logical_screen_descriptor = self._root.LogicalScreenDescriptor(self._io, self, self._root)
if self.logical_screen_descriptor.has_color_table:
self._raw_global_color_table = self._io.read_bytes((self.logical_screen_descriptor.color_table_size * 3))
io = KaitaiStream(BytesIO(self._raw_global_color_table))
self.global_color_table = self._root.ColorTable(io, self, self._root)
self.blocks = []
while not self._io.is_eof():
self.blocks.append(self._root.Block(self._io, self, self._root))
class ImageData(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.lzw_min_code_size = self._io.read_u1()
self.subblocks = self._root.Subblocks(self._io, self, self._root)
class ColorTableEntry(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.red = self._io.read_u1()
self.green = self._io.read_u1()
self.blue = self._io.read_u1()
class LogicalScreenDescriptor(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.screen_width = self._io.read_u2le()
self.screen_height = self._io.read_u2le()
self.flags = self._io.read_u1()
self.bg_color_index = self._io.read_u1()
self.pixel_aspect_ratio = self._io.read_u1()
@property
def has_color_table(self):
if hasattr(self, '_m_has_color_table'):
return self._m_has_color_table if hasattr(self, '_m_has_color_table') else None
self._m_has_color_table = (self.flags & 128) != 0
return self._m_has_color_table if hasattr(self, '_m_has_color_table') else None
@property
def color_table_size(self):
if hasattr(self, '_m_color_table_size'):
return self._m_color_table_size if hasattr(self, '_m_color_table_size') else None
self._m_color_table_size = (2 << (self.flags & 7))
return self._m_color_table_size if hasattr(self, '_m_color_table_size') else None
class LocalImageDescriptor(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.left = self._io.read_u2le()
self.top = self._io.read_u2le()
self.width = self._io.read_u2le()
self.height = self._io.read_u2le()
self.flags = self._io.read_u1()
if self.has_color_table:
self._raw_local_color_table = self._io.read_bytes((self.color_table_size * 3))
io = KaitaiStream(BytesIO(self._raw_local_color_table))
self.local_color_table = self._root.ColorTable(io, self, self._root)
self.image_data = self._root.ImageData(self._io, self, self._root)
@property
def has_color_table(self):
if hasattr(self, '_m_has_color_table'):
return self._m_has_color_table if hasattr(self, '_m_has_color_table') else None
self._m_has_color_table = (self.flags & 128) != 0
return self._m_has_color_table if hasattr(self, '_m_has_color_table') else None
@property
def has_interlace(self):
if hasattr(self, '_m_has_interlace'):
return self._m_has_interlace if hasattr(self, '_m_has_interlace') else None
self._m_has_interlace = (self.flags & 64) != 0
return self._m_has_interlace if hasattr(self, '_m_has_interlace') else None
@property
def has_sorted_color_table(self):
if hasattr(self, '_m_has_sorted_color_table'):
return self._m_has_sorted_color_table if hasattr(self, '_m_has_sorted_color_table') else None
self._m_has_sorted_color_table = (self.flags & 32) != 0
return self._m_has_sorted_color_table if hasattr(self, '_m_has_sorted_color_table') else None
@property
def color_table_size(self):
if hasattr(self, '_m_color_table_size'):
return self._m_color_table_size if hasattr(self, '_m_color_table_size') else None
self._m_color_table_size = (2 << (self.flags & 7))
return self._m_color_table_size if hasattr(self, '_m_color_table_size') else None
class Block(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.block_type = self._root.BlockType(self._io.read_u1())
_on = self.block_type
if _on == self._root.BlockType.extension:
self.body = self._root.Extension(self._io, self, self._root)
elif _on == self._root.BlockType.local_image_descriptor:
self.body = self._root.LocalImageDescriptor(self._io, self, self._root)
class ColorTable(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.entries = []
while not self._io.is_eof():
self.entries.append(self._root.ColorTableEntry(self._io, self, self._root))
class Header(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.magic = self._io.ensure_fixed_contents(struct.pack('3b', 71, 73, 70))
self.version = self._io.read_bytes(3)
class ExtGraphicControl(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.block_size = self._io.ensure_fixed_contents(struct.pack('1b', 4))
self.flags = self._io.read_u1()
self.delay_time = self._io.read_u2le()
self.transparent_idx = self._io.read_u1()
self.terminator = self._io.ensure_fixed_contents(struct.pack('1b', 0))
@property
def transparent_color_flag(self):
if hasattr(self, '_m_transparent_color_flag'):
return self._m_transparent_color_flag if hasattr(self, '_m_transparent_color_flag') else None
self._m_transparent_color_flag = (self.flags & 1) != 0
return self._m_transparent_color_flag if hasattr(self, '_m_transparent_color_flag') else None
@property
def user_input_flag(self):
if hasattr(self, '_m_user_input_flag'):
return self._m_user_input_flag if hasattr(self, '_m_user_input_flag') else None
self._m_user_input_flag = (self.flags & 2) != 0
return self._m_user_input_flag if hasattr(self, '_m_user_input_flag') else None
class Subblock(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.num_bytes = self._io.read_u1()
self.bytes = self._io.read_bytes(self.num_bytes)
class ExtApplication(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.application_id = self._root.Subblock(self._io, self, self._root)
self.subblocks = []
while True:
_ = self._root.Subblock(self._io, self, self._root)
self.subblocks.append(_)
if _.num_bytes == 0:
break
class Subblocks(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.entries = []
while True:
_ = self._root.Subblock(self._io, self, self._root)
self.entries.append(_)
if _.num_bytes == 0:
break
class Extension(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self.label = self._root.ExtensionLabel(self._io.read_u1())
_on = self.label
if _on == self._root.ExtensionLabel.application:
self.body = self._root.ExtApplication(self._io, self, self._root)
elif _on == self._root.ExtensionLabel.comment:
self.body = self._root.Subblocks(self._io, self, self._root)
elif _on == self._root.ExtensionLabel.graphic_control:
self.body = self._root.ExtGraphicControl(self._io, self, self._root)
else:
self.body = self._root.Subblocks(self._io, self, self._root)
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