mirror of
https://github.com/SickGear/SickGear.git
synced 2024-12-27 05:03:37 +00:00
294 lines
9.1 KiB
Python
294 lines
9.1 KiB
Python
"""
|
|
PNG picture file parser.
|
|
|
|
Documents:
|
|
- RFC 2083
|
|
http://www.faqs.org/rfcs/rfc2083.html
|
|
|
|
Author: Victor Stinner
|
|
"""
|
|
|
|
from hachoir.parser import Parser
|
|
from hachoir.field import (FieldSet, Fragment,
|
|
ParserError, MissingField,
|
|
UInt8, UInt16, UInt32,
|
|
String, CString,
|
|
Bytes, RawBytes,
|
|
Bit, NullBits,
|
|
Enum, CompressedField)
|
|
from hachoir.parser.image.common import RGB
|
|
from hachoir.core.text_handler import textHandler, hexadecimal
|
|
from hachoir.core.endian import NETWORK_ENDIAN
|
|
from hachoir.core.tools import humanFilesize
|
|
from datetime import datetime
|
|
|
|
MAX_FILESIZE = 500 * 1024 * 1024 # 500 MB
|
|
|
|
try:
|
|
from zlib import decompressobj
|
|
|
|
class Gunzip:
|
|
|
|
def __init__(self, stream):
|
|
self.gzip = decompressobj()
|
|
|
|
def __call__(self, size, data=None):
|
|
if data is None:
|
|
data = self.gzip.unconsumed_tail
|
|
return self.gzip.decompress(data, size)
|
|
|
|
has_deflate = True
|
|
except ImportError:
|
|
has_deflate = False
|
|
|
|
UNIT_NAME = {1: "Meter"}
|
|
COMPRESSION_NAME = {
|
|
0: "deflate" # with 32K sliding window
|
|
}
|
|
MAX_CHUNK_SIZE = 64 * 1024 * 1024 # Maximum chunk size heuristic (64 MB)
|
|
|
|
|
|
def headerParse(parent):
|
|
yield UInt32(parent, "width", "Width (pixels)")
|
|
yield UInt32(parent, "height", "Height (pixels)")
|
|
yield UInt8(parent, "bit_depth", "Bit depth")
|
|
yield NullBits(parent, "reserved", 5)
|
|
yield Bit(parent, "has_alpha", "Has alpha channel?")
|
|
yield Bit(parent, "color", "Color used?")
|
|
yield Bit(parent, "has_palette", "Has a color palette?")
|
|
yield Enum(UInt8(parent, "compression", "Compression method"), COMPRESSION_NAME)
|
|
yield UInt8(parent, "filter", "Filter method")
|
|
yield UInt8(parent, "interlace", "Interlace method")
|
|
|
|
|
|
def headerDescription(parent):
|
|
return "Header: %ux%u pixels and %u bits/pixel" % \
|
|
(parent["width"].value, parent[
|
|
"height"].value, getBitsPerPixel(parent))
|
|
|
|
|
|
def paletteParse(parent):
|
|
size = parent["size"].value
|
|
if (size % 3) != 0:
|
|
raise ParserError(
|
|
"Palette have invalid size (%s), should be 3*n!" % size)
|
|
nb_colors = size // 3
|
|
for index in range(nb_colors):
|
|
yield RGB(parent, "color[]")
|
|
|
|
|
|
def paletteDescription(parent):
|
|
return "Palette: %u colors" % (parent["size"].value // 3)
|
|
|
|
|
|
def gammaParse(parent):
|
|
yield UInt32(parent, "gamma", "Gamma (x100,000)")
|
|
|
|
|
|
def gammaValue(parent):
|
|
return float(parent["gamma"].value) / 100000
|
|
|
|
|
|
def gammaDescription(parent):
|
|
return "Gamma: %.3f" % parent.value
|
|
|
|
|
|
def textParse(parent):
|
|
yield CString(parent, "keyword", "Keyword", charset="ISO-8859-1")
|
|
length = parent["size"].value - parent["keyword"].size // 8
|
|
if length:
|
|
yield String(parent, "text", length, "Text", charset="ISO-8859-1")
|
|
|
|
|
|
def textDescription(parent):
|
|
if "text" in parent:
|
|
return 'Text: %s' % parent["text"].display
|
|
else:
|
|
return 'Text'
|
|
|
|
|
|
def timestampParse(parent):
|
|
yield UInt16(parent, "year", "Year")
|
|
yield UInt8(parent, "month", "Month")
|
|
yield UInt8(parent, "day", "Day")
|
|
yield UInt8(parent, "hour", "Hour")
|
|
yield UInt8(parent, "minute", "Minute")
|
|
yield UInt8(parent, "second", "Second")
|
|
|
|
|
|
def timestampValue(parent):
|
|
value = datetime(
|
|
parent["year"].value, parent["month"].value, parent["day"].value,
|
|
parent["hour"].value, parent["minute"].value, parent["second"].value)
|
|
return value
|
|
|
|
|
|
def physicalParse(parent):
|
|
yield UInt32(parent, "pixel_per_unit_x", "Pixel per unit, X axis")
|
|
yield UInt32(parent, "pixel_per_unit_y", "Pixel per unit, Y axis")
|
|
yield Enum(UInt8(parent, "unit", "Unit type"), UNIT_NAME)
|
|
|
|
|
|
def physicalDescription(parent):
|
|
x = parent["pixel_per_unit_x"].value
|
|
y = parent["pixel_per_unit_y"].value
|
|
desc = "Physical: %ux%u pixels" % (x, y)
|
|
if parent["unit"].value == 1:
|
|
desc += " per meter"
|
|
return desc
|
|
|
|
|
|
def parseBackgroundColor(parent):
|
|
yield UInt16(parent, "red")
|
|
yield UInt16(parent, "green")
|
|
yield UInt16(parent, "blue")
|
|
|
|
|
|
def backgroundColorDesc(parent):
|
|
rgb = parent["red"].value, parent["green"].value, parent["blue"].value
|
|
name = RGB.color_name.get(rgb)
|
|
if not name:
|
|
name = "#%02X%02X%02X" % rgb
|
|
return "Background color: %s" % name
|
|
|
|
|
|
class ImageData(Fragment):
|
|
|
|
def __init__(self, parent, name="compressed_data"):
|
|
Fragment.__init__(self, parent, name, None, 8 * parent["size"].value)
|
|
data = parent.name.split('[')
|
|
data, next = "../%s[%%u]" % data[0], int(data[1][:-1]) + 1
|
|
first = parent.getField(data % 0)
|
|
if first is parent:
|
|
first = None
|
|
if has_deflate:
|
|
CompressedField(self, Gunzip)
|
|
else:
|
|
first = first[name]
|
|
try:
|
|
_next = parent[data % next]
|
|
|
|
def next():
|
|
return _next[name]
|
|
except MissingField:
|
|
next = None
|
|
self.setLinks(first, next)
|
|
|
|
|
|
def parseTransparency(parent):
|
|
for i in range(parent["size"].value):
|
|
yield UInt8(parent, "alpha_value[]", "Alpha value for palette entry %i" % i)
|
|
|
|
|
|
def getBitsPerPixel(header):
|
|
nr_component = 1
|
|
if header["has_alpha"].value:
|
|
nr_component += 1
|
|
if header["color"].value and not header["has_palette"].value:
|
|
nr_component += 2
|
|
return nr_component * header["bit_depth"].value
|
|
|
|
|
|
class Chunk(FieldSet):
|
|
TAG_INFO = {
|
|
"tIME": ("time", timestampParse, "Timestamp", timestampValue),
|
|
"pHYs": ("physical", physicalParse, physicalDescription, None),
|
|
"IHDR": ("header", headerParse, headerDescription, None),
|
|
"PLTE": ("palette", paletteParse, paletteDescription, None),
|
|
"gAMA": ("gamma", gammaParse, gammaDescription, gammaValue),
|
|
"tEXt": ("text[]", textParse, textDescription, None),
|
|
"tRNS": ("transparency", parseTransparency, "Transparency Info", None),
|
|
|
|
"bKGD": ("background", parseBackgroundColor, backgroundColorDesc, None),
|
|
"IDAT": ("data[]", lambda parent: (ImageData(parent),), "Image data", None),
|
|
"iTXt": ("utf8_text[]", None, "International text (encoded in UTF-8)", None),
|
|
"zTXt": ("comp_text[]", None, "Compressed text", None),
|
|
"IEND": ("end", None, "End", None)
|
|
}
|
|
|
|
def createValueFunc(self):
|
|
return self.value_func(self)
|
|
|
|
def __init__(self, parent, name, description=None):
|
|
FieldSet.__init__(self, parent, name, description)
|
|
self._size = (self["size"].value + 3 * 4) * 8
|
|
if MAX_CHUNK_SIZE < (self._size // 8):
|
|
raise ParserError("PNG: Chunk is too big (%s)"
|
|
% humanFilesize(self._size // 8))
|
|
tag = self["tag"].value
|
|
self.desc_func = None
|
|
self.value_func = None
|
|
if tag in self.TAG_INFO:
|
|
self._name, self.parse_func, desc, value_func = self.TAG_INFO[tag]
|
|
if value_func:
|
|
self.value_func = value_func
|
|
self.createValue = self.createValueFunc
|
|
if desc:
|
|
if isinstance(desc, str):
|
|
self._description = desc
|
|
else:
|
|
self.desc_func = desc
|
|
else:
|
|
self._description = ""
|
|
self.parse_func = None
|
|
|
|
def createFields(self):
|
|
yield UInt32(self, "size", "Size")
|
|
yield String(self, "tag", 4, "Tag", charset="ASCII")
|
|
|
|
size = self["size"].value
|
|
if size != 0:
|
|
if self.parse_func:
|
|
yield from self.parse_func(self)
|
|
else:
|
|
yield RawBytes(self, "content", size, "Data")
|
|
yield textHandler(UInt32(self, "crc32", "CRC32"), hexadecimal)
|
|
|
|
def createDescription(self):
|
|
if self.desc_func:
|
|
return self.desc_func(self)
|
|
else:
|
|
return "Chunk: %s" % self["tag"].display
|
|
|
|
|
|
class PngFile(Parser):
|
|
PARSER_TAGS = {
|
|
"id": "png",
|
|
"category": "image",
|
|
"file_ext": ("png",),
|
|
"mime": ("image/png", "image/x-png"),
|
|
"min_size": 8 * 8, # just the identifier
|
|
"magic": [(b'\x89PNG\r\n\x1A\n', 0)],
|
|
"description": "Portable Network Graphics (PNG) picture"
|
|
}
|
|
endian = NETWORK_ENDIAN
|
|
|
|
def validate(self):
|
|
if self["id"].value != b'\x89PNG\r\n\x1A\n':
|
|
return "Invalid signature"
|
|
if self[1].name != "header":
|
|
return "First chunk is not header"
|
|
return True
|
|
|
|
def createFields(self):
|
|
yield Bytes(self, "id", 8, r"PNG identifier ('\x89PNG\r\n\x1A\n')")
|
|
while not self.eof:
|
|
yield Chunk(self, "chunk[]")
|
|
|
|
def createDescription(self):
|
|
header = self["header"]
|
|
desc = "PNG picture: %ux%ux%u" % (
|
|
header["width"].value, header["height"].value, getBitsPerPixel(header))
|
|
if header["has_alpha"].value:
|
|
desc += " (alpha layer)"
|
|
return desc
|
|
|
|
def createContentSize(self):
|
|
field = self["header"]
|
|
start = field.absolute_address + field.size
|
|
end = MAX_FILESIZE * 8
|
|
pos = self.stream.searchBytes(
|
|
b"\0\0\0\0IEND\xae\x42\x60\x82", start, end)
|
|
if pos is not None:
|
|
return pos + 12 * 8
|
|
return None
|