test-kivy-app/kivy_venv/lib/python3.11/site-packages/PIL/EpsImagePlugin.py

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2024-09-15 12:12:16 +00:00
#
# The Python Imaging Library.
# $Id$
#
# EPS file handling
#
# History:
# 1995-09-01 fl Created (0.1)
# 1996-05-18 fl Don't choke on "atend" fields, Ghostscript interface (0.2)
# 1996-08-22 fl Don't choke on floating point BoundingBox values
# 1996-08-23 fl Handle files from Macintosh (0.3)
# 2001-02-17 fl Use 're' instead of 'regex' (Python 2.1) (0.4)
# 2003-09-07 fl Check gs.close status (from Federico Di Gregorio) (0.5)
# 2014-05-07 e Handling of EPS with binary preview and fixed resolution
# resizing
#
# Copyright (c) 1997-2003 by Secret Labs AB.
# Copyright (c) 1995-2003 by Fredrik Lundh
#
# See the README file for information on usage and redistribution.
#
from __future__ import annotations
import io
import os
import re
import subprocess
import sys
import tempfile
from typing import IO
from . import Image, ImageFile
from ._binary import i32le as i32
from ._deprecate import deprecate
# --------------------------------------------------------------------
split = re.compile(r"^%%([^:]*):[ \t]*(.*)[ \t]*$")
field = re.compile(r"^%[%!\w]([^:]*)[ \t]*$")
gs_binary: str | bool | None = None
gs_windows_binary = None
def has_ghostscript() -> bool:
global gs_binary, gs_windows_binary
if gs_binary is None:
if sys.platform.startswith("win"):
if gs_windows_binary is None:
import shutil
for binary in ("gswin32c", "gswin64c", "gs"):
if shutil.which(binary) is not None:
gs_windows_binary = binary
break
else:
gs_windows_binary = False
gs_binary = gs_windows_binary
else:
try:
subprocess.check_call(["gs", "--version"], stdout=subprocess.DEVNULL)
gs_binary = "gs"
except OSError:
gs_binary = False
return gs_binary is not False
def Ghostscript(tile, size, fp, scale=1, transparency=False):
"""Render an image using Ghostscript"""
global gs_binary
if not has_ghostscript():
msg = "Unable to locate Ghostscript on paths"
raise OSError(msg)
# Unpack decoder tile
decoder, tile, offset, data = tile[0]
length, bbox = data
# Hack to support hi-res rendering
scale = int(scale) or 1
width = size[0] * scale
height = size[1] * scale
# resolution is dependent on bbox and size
res_x = 72.0 * width / (bbox[2] - bbox[0])
res_y = 72.0 * height / (bbox[3] - bbox[1])
out_fd, outfile = tempfile.mkstemp()
os.close(out_fd)
infile_temp = None
if hasattr(fp, "name") and os.path.exists(fp.name):
infile = fp.name
else:
in_fd, infile_temp = tempfile.mkstemp()
os.close(in_fd)
infile = infile_temp
# Ignore length and offset!
# Ghostscript can read it
# Copy whole file to read in Ghostscript
with open(infile_temp, "wb") as f:
# fetch length of fp
fp.seek(0, io.SEEK_END)
fsize = fp.tell()
# ensure start position
# go back
fp.seek(0)
lengthfile = fsize
while lengthfile > 0:
s = fp.read(min(lengthfile, 100 * 1024))
if not s:
break
lengthfile -= len(s)
f.write(s)
device = "pngalpha" if transparency else "ppmraw"
# Build Ghostscript command
command = [
gs_binary,
"-q", # quiet mode
f"-g{width:d}x{height:d}", # set output geometry (pixels)
f"-r{res_x:f}x{res_y:f}", # set input DPI (dots per inch)
"-dBATCH", # exit after processing
"-dNOPAUSE", # don't pause between pages
"-dSAFER", # safe mode
f"-sDEVICE={device}",
f"-sOutputFile={outfile}", # output file
# adjust for image origin
"-c",
f"{-bbox[0]} {-bbox[1]} translate",
"-f",
infile, # input file
# showpage (see https://bugs.ghostscript.com/show_bug.cgi?id=698272)
"-c",
"showpage",
]
# push data through Ghostscript
try:
startupinfo = None
if sys.platform.startswith("win"):
startupinfo = subprocess.STARTUPINFO()
startupinfo.dwFlags |= subprocess.STARTF_USESHOWWINDOW
subprocess.check_call(command, startupinfo=startupinfo)
out_im = Image.open(outfile)
out_im.load()
finally:
try:
os.unlink(outfile)
if infile_temp:
os.unlink(infile_temp)
except OSError:
pass
im = out_im.im.copy()
out_im.close()
return im
class PSFile:
"""
Wrapper for bytesio object that treats either CR or LF as end of line.
This class is no longer used internally, but kept for backwards compatibility.
"""
def __init__(self, fp):
deprecate(
"PSFile",
11,
action="If you need the functionality of this class "
"you will need to implement it yourself.",
)
self.fp = fp
self.char = None
def seek(self, offset, whence=io.SEEK_SET):
self.char = None
self.fp.seek(offset, whence)
def readline(self) -> str:
s = [self.char or b""]
self.char = None
c = self.fp.read(1)
while (c not in b"\r\n") and len(c):
s.append(c)
c = self.fp.read(1)
self.char = self.fp.read(1)
# line endings can be 1 or 2 of \r \n, in either order
if self.char in b"\r\n":
self.char = None
return b"".join(s).decode("latin-1")
def _accept(prefix: bytes) -> bool:
return prefix[:4] == b"%!PS" or (len(prefix) >= 4 and i32(prefix) == 0xC6D3D0C5)
##
# Image plugin for Encapsulated PostScript. This plugin supports only
# a few variants of this format.
class EpsImageFile(ImageFile.ImageFile):
"""EPS File Parser for the Python Imaging Library"""
format = "EPS"
format_description = "Encapsulated Postscript"
mode_map = {1: "L", 2: "LAB", 3: "RGB", 4: "CMYK"}
def _open(self) -> None:
(length, offset) = self._find_offset(self.fp)
# go to offset - start of "%!PS"
self.fp.seek(offset)
self._mode = "RGB"
self._size = None
byte_arr = bytearray(255)
bytes_mv = memoryview(byte_arr)
bytes_read = 0
reading_header_comments = True
reading_trailer_comments = False
trailer_reached = False
def check_required_header_comments() -> None:
"""
The EPS specification requires that some headers exist.
This should be checked when the header comments formally end,
when image data starts, or when the file ends, whichever comes first.
"""
if "PS-Adobe" not in self.info:
msg = 'EPS header missing "%!PS-Adobe" comment'
raise SyntaxError(msg)
if "BoundingBox" not in self.info:
msg = 'EPS header missing "%%BoundingBox" comment'
raise SyntaxError(msg)
def _read_comment(s: str) -> bool:
nonlocal reading_trailer_comments
try:
m = split.match(s)
except re.error as e:
msg = "not an EPS file"
raise SyntaxError(msg) from e
if not m:
return False
k, v = m.group(1, 2)
self.info[k] = v
if k == "BoundingBox":
if v == "(atend)":
reading_trailer_comments = True
elif not self._size or (trailer_reached and reading_trailer_comments):
try:
# Note: The DSC spec says that BoundingBox
# fields should be integers, but some drivers
# put floating point values there anyway.
box = [int(float(i)) for i in v.split()]
self._size = box[2] - box[0], box[3] - box[1]
self.tile = [("eps", (0, 0) + self.size, offset, (length, box))]
except Exception:
pass
return True
while True:
byte = self.fp.read(1)
if byte == b"":
# if we didn't read a byte we must be at the end of the file
if bytes_read == 0:
if reading_header_comments:
check_required_header_comments()
break
elif byte in b"\r\n":
# if we read a line ending character, ignore it and parse what
# we have already read. if we haven't read any other characters,
# continue reading
if bytes_read == 0:
continue
else:
# ASCII/hexadecimal lines in an EPS file must not exceed
# 255 characters, not including line ending characters
if bytes_read >= 255:
# only enforce this for lines starting with a "%",
# otherwise assume it's binary data
if byte_arr[0] == ord("%"):
msg = "not an EPS file"
raise SyntaxError(msg)
else:
if reading_header_comments:
check_required_header_comments()
reading_header_comments = False
# reset bytes_read so we can keep reading
# data until the end of the line
bytes_read = 0
byte_arr[bytes_read] = byte[0]
bytes_read += 1
continue
if reading_header_comments:
# Load EPS header
# if this line doesn't start with a "%",
# or does start with "%%EndComments",
# then we've reached the end of the header/comments
if byte_arr[0] != ord("%") or bytes_mv[:13] == b"%%EndComments":
check_required_header_comments()
reading_header_comments = False
continue
s = str(bytes_mv[:bytes_read], "latin-1")
if not _read_comment(s):
m = field.match(s)
if m:
k = m.group(1)
if k[:8] == "PS-Adobe":
self.info["PS-Adobe"] = k[9:]
else:
self.info[k] = ""
elif s[0] == "%":
# handle non-DSC PostScript comments that some
# tools mistakenly put in the Comments section
pass
else:
msg = "bad EPS header"
raise OSError(msg)
elif bytes_mv[:11] == b"%ImageData:":
# Check for an "ImageData" descriptor
# https://www.adobe.com/devnet-apps/photoshop/fileformatashtml/#50577413_pgfId-1035096
# Values:
# columns
# rows
# bit depth (1 or 8)
# mode (1: L, 2: LAB, 3: RGB, 4: CMYK)
# number of padding channels
# block size (number of bytes per row per channel)
# binary/ascii (1: binary, 2: ascii)
# data start identifier (the image data follows after a single line
# consisting only of this quoted value)
image_data_values = byte_arr[11:bytes_read].split(None, 7)
columns, rows, bit_depth, mode_id = (
int(value) for value in image_data_values[:4]
)
if bit_depth == 1:
self._mode = "1"
elif bit_depth == 8:
try:
self._mode = self.mode_map[mode_id]
except ValueError:
break
else:
break
self._size = columns, rows
return
elif bytes_mv[:5] == b"%%EOF":
break
elif trailer_reached and reading_trailer_comments:
# Load EPS trailer
s = str(bytes_mv[:bytes_read], "latin-1")
_read_comment(s)
elif bytes_mv[:9] == b"%%Trailer":
trailer_reached = True
bytes_read = 0
if not self._size:
msg = "cannot determine EPS bounding box"
raise OSError(msg)
def _find_offset(self, fp):
s = fp.read(4)
if s == b"%!PS":
# for HEAD without binary preview
fp.seek(0, io.SEEK_END)
length = fp.tell()
offset = 0
elif i32(s) == 0xC6D3D0C5:
# FIX for: Some EPS file not handled correctly / issue #302
# EPS can contain binary data
# or start directly with latin coding
# more info see:
# https://web.archive.org/web/20160528181353/http://partners.adobe.com/public/developer/en/ps/5002.EPSF_Spec.pdf
s = fp.read(8)
offset = i32(s)
length = i32(s, 4)
else:
msg = "not an EPS file"
raise SyntaxError(msg)
return length, offset
def load(self, scale=1, transparency=False):
# Load EPS via Ghostscript
if self.tile:
self.im = Ghostscript(self.tile, self.size, self.fp, scale, transparency)
self._mode = self.im.mode
self._size = self.im.size
self.tile = []
return Image.Image.load(self)
def load_seek(self, pos: int) -> None:
# we can't incrementally load, so force ImageFile.parser to
# use our custom load method by defining this method.
pass
# --------------------------------------------------------------------
def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes, eps: int = 1) -> None:
"""EPS Writer for the Python Imaging Library."""
# make sure image data is available
im.load()
# determine PostScript image mode
if im.mode == "L":
operator = (8, 1, b"image")
elif im.mode == "RGB":
operator = (8, 3, b"false 3 colorimage")
elif im.mode == "CMYK":
operator = (8, 4, b"false 4 colorimage")
else:
msg = "image mode is not supported"
raise ValueError(msg)
if eps:
# write EPS header
fp.write(b"%!PS-Adobe-3.0 EPSF-3.0\n")
fp.write(b"%%Creator: PIL 0.1 EpsEncode\n")
# fp.write("%%CreationDate: %s"...)
fp.write(b"%%%%BoundingBox: 0 0 %d %d\n" % im.size)
fp.write(b"%%Pages: 1\n")
fp.write(b"%%EndComments\n")
fp.write(b"%%Page: 1 1\n")
fp.write(b"%%ImageData: %d %d " % im.size)
fp.write(b'%d %d 0 1 1 "%s"\n' % operator)
# image header
fp.write(b"gsave\n")
fp.write(b"10 dict begin\n")
fp.write(b"/buf %d string def\n" % (im.size[0] * operator[1]))
fp.write(b"%d %d scale\n" % im.size)
fp.write(b"%d %d 8\n" % im.size) # <= bits
fp.write(b"[%d 0 0 -%d 0 %d]\n" % (im.size[0], im.size[1], im.size[1]))
fp.write(b"{ currentfile buf readhexstring pop } bind\n")
fp.write(operator[2] + b"\n")
if hasattr(fp, "flush"):
fp.flush()
ImageFile._save(im, fp, [("eps", (0, 0) + im.size, 0, None)])
fp.write(b"\n%%%%EndBinary\n")
fp.write(b"grestore end\n")
if hasattr(fp, "flush"):
fp.flush()
# --------------------------------------------------------------------
Image.register_open(EpsImageFile.format, EpsImageFile, _accept)
Image.register_save(EpsImageFile.format, _save)
Image.register_extensions(EpsImageFile.format, [".ps", ".eps"])
Image.register_mime(EpsImageFile.format, "application/postscript")