Module fpdf.image_parsing
Expand source code Browse git
import base64, hashlib, io, zlib
from dataclasses import dataclass
from io import BytesIO
from math import ceil
from urllib.request import urlopen
from pathlib import Path
import logging
try:
from PIL import Image, TiffImagePlugin
from PIL import ImageCms
try:
from PIL.Image import Resampling
RESAMPLE = Resampling.LANCZOS
except ImportError: # For Pillow < 9.1.0
# pylint: disable=no-member, useless-suppression
RESAMPLE = Image.ANTIALIAS
except ImportError:
Image = None
from .errors import FPDFException
from .image_datastructures import ImageCache, RasterImageInfo, VectorImageInfo
from .svg import SVGObject
@dataclass
class ImageSettings:
# Passed to zlib.compress() - In range 0-9 - Default is currently equivalent to 6:
compression_level: int = -1
LOGGER = logging.getLogger(__name__)
SUPPORTED_IMAGE_FILTERS = ("AUTO", "FlateDecode", "DCTDecode", "JPXDecode")
SETTINGS = ImageSettings()
# fmt: off
TIFFBitRevTable = [
0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, 0x10, 0x90,
0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0, 0x08, 0x88, 0x48, 0xC8,
0x28, 0xA8, 0x68, 0xE8, 0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8,
0x78, 0xF8, 0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4,
0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4, 0x0C, 0x8C,
0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC, 0x1C, 0x9C, 0x5C, 0xDC,
0x3C, 0xBC, 0x7C, 0xFC, 0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2,
0x62, 0xE2, 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2,
0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA, 0x1A, 0x9A,
0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA, 0x06, 0x86, 0x46, 0xC6,
0x26, 0xA6, 0x66, 0xE6, 0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6,
0x76, 0xF6, 0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE,
0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE, 0x01, 0x81,
0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1, 0x11, 0x91, 0x51, 0xD1,
0x31, 0xB1, 0x71, 0xF1, 0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9,
0x69, 0xE9, 0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9,
0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5, 0x15, 0x95,
0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5, 0x0D, 0x8D, 0x4D, 0xCD,
0x2D, 0xAD, 0x6D, 0xED, 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD,
0x7D, 0xFD, 0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3,
0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3, 0x0B, 0x8B,
0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB, 0x1B, 0x9B, 0x5B, 0xDB,
0x3B, 0xBB, 0x7B, 0xFB, 0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7,
0x67, 0xE7, 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, 0x1F, 0x9F,
0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF,
]
# fmt: on
def preload_image(image_cache: ImageCache, name, dims=None):
"""
Read an image and load it into memory.
For raster images: following this call, the image is inserted in `image_cache.images`,
and following calls to `FPDF.image()` will re-use the same cached values, without re-reading the image.
For vector images: the data is loaded and the metadata extracted.
Args:
image_cache: an `ImageCache` instance, usually the `.image_cache` attribute of a `FPDF` instance.
name: either a string representing a file path to an image, an URL to an image,
an io.BytesIO, or a instance of `PIL.Image.Image`.
dims (Tuple[float]): optional dimensions as a tuple (width, height) to resize the image
(raster only) before storing it in the PDF.
Returns: A tuple, consisting of 3 values: the name, the image data,
and an instance of a subclass of `ImageInfo`.
"""
# Identify and load SVG data:
if str(name).endswith(".svg"):
return get_svg_info(name, load_image(str(name)), image_cache=image_cache)
if isinstance(name, bytes) and _is_svg(name.strip()):
return get_svg_info(name, io.BytesIO(name), image_cache=image_cache)
if isinstance(name, io.BytesIO) and _is_svg(name.getvalue().strip()):
return get_svg_info("vector_image", name, image_cache=image_cache)
# Load raster data.
if isinstance(name, str):
img = None
elif isinstance(name, Image.Image):
bytes_ = name.tobytes()
img_hash = hashlib.new("md5", usedforsecurity=False) # nosec B324
img_hash.update(bytes_)
name, img = img_hash.hexdigest(), name
elif isinstance(name, (bytes, io.BytesIO)):
bytes_ = name.getvalue() if isinstance(name, io.BytesIO) else name
bytes_ = bytes_.strip()
img_hash = hashlib.new("md5", usedforsecurity=False) # nosec B324
img_hash.update(bytes_)
name, img = img_hash.hexdigest(), name
else:
name, img = str(name), name
info = image_cache.images.get(name)
if info:
info["usages"] += 1
else:
info = get_img_info(name, img, image_cache.image_filter, dims)
info["i"] = len(image_cache.images) + 1
info["usages"] = 1
info["iccp_i"] = None
iccp = info.get("iccp")
if iccp:
LOGGER.debug(
"ICC profile found for image %s - It will be inserted in the PDF document",
name,
)
if iccp in image_cache.icc_profiles:
info["iccp_i"] = image_cache.icc_profiles[iccp]
else:
iccp_i = len(image_cache.icc_profiles)
image_cache.icc_profiles[iccp] = iccp_i
info["iccp_i"] = iccp_i
info["iccp"] = None
image_cache.images[name] = info
return name, img, info
def _is_svg(bytes_):
return bytes_.startswith(b"<?xml ") or bytes_.startswith(b"<svg ")
def load_image(filename):
"""
This method is used to load external resources, such as images.
It is automatically called when resource added to document by `fpdf.FPDF.image()`.
It always return a BytesIO buffer.
"""
# if a bytesio instance is passed in, use it as is.
if isinstance(filename, BytesIO):
return filename
if isinstance(filename, Path):
filename = str(filename)
# by default loading from network is allowed for all images
if filename.startswith(("http://", "https://")):
# disabling bandit & semgrep rules as permitted schemes are whitelisted:
# nosemgrep: python.lang.security.audit.dynamic-urllib-use-detected.dynamic-urllib-use-detected
with urlopen(filename) as url_file: # nosec B310
return BytesIO(url_file.read())
elif filename.startswith("data:"):
return _decode_base64_image(filename)
with open(filename, "rb") as local_file:
return BytesIO(local_file.read())
def _decode_base64_image(base64Image):
"Decode the base 64 image string into an io byte stream."
frags = base64Image.split("base64,")
if len(frags) != 2:
raise NotImplementedError("Unsupported non-base64 image data")
imageData = frags[1]
decodedData = base64.b64decode(imageData)
return BytesIO(decodedData)
def is_iccp_valid(iccp, filename):
"Checks the validity of an ICC profile"
try:
profile = ImageCms.getOpenProfile(BytesIO(iccp))
except ImageCms.PyCMSError:
LOGGER.info("Invalid ICC Profile in file %s", filename)
return False
color_space = profile.profile.xcolor_space.strip()
if color_space not in ("GRAY", "RGB"):
LOGGER.info(
"Unsupported color space %s in ICC Profile of file %s - cf. issue #711",
color_space,
filename,
)
return False
return True
def get_svg_info(filename, img, image_cache):
svg = SVGObject(img.getvalue(), image_cache=image_cache)
if svg.viewbox:
_, _, w, h = svg.viewbox
else:
w = h = 0.0
if svg.width:
w = svg.width
if svg.height:
h = svg.height
info = VectorImageInfo(data=svg, w=w, h=h)
return filename, svg, info
def get_img_info(filename, img=None, image_filter="AUTO", dims=None):
"""
Args:
filename: in a format that can be passed to load_image
img: optional `bytes`, `BytesIO` or `PIL.Image.Image` instance
image_filter (str): one of the SUPPORTED_IMAGE_FILTERS
"""
if Image is None:
raise EnvironmentError("Pillow not available - fpdf2 cannot insert images")
is_pil_img = True
keep_bytes_io_open = False
# Flag to check whether a cmyk image is jpeg or not, if set to True the decode array
# is inverted in output.py
jpeg_inverted = False
img_raw_data = None
if not img or isinstance(img, (Path, str)):
img_raw_data = load_image(filename)
img = Image.open(img_raw_data)
is_pil_img = False
elif not isinstance(img, Image.Image):
keep_bytes_io_open = isinstance(img, BytesIO)
img_raw_data = BytesIO(img) if isinstance(img, bytes) else img
img = Image.open(img_raw_data)
is_pil_img = False
img_altered = False
if dims:
img = img.resize(dims, resample=RESAMPLE)
img_altered = True
if image_filter == "AUTO":
# Very simple logic for now:
if img.format == "JPEG":
image_filter = "DCTDecode"
elif img.mode == "1" and hasattr(Image.core, "libtiff_support_custom_tags"):
# The 2nd condition prevents from running in a bug sometimes,
# cf. test_transcode_monochrome_and_libtiff_support_custom_tags()
image_filter = "CCITTFaxDecode"
else:
image_filter = "FlateDecode"
if img.mode in ("P", "PA") and image_filter != "FlateDecode":
img = img.convert("RGBA")
if img.mode not in ("1", "L", "LA", "RGB", "RGBA", "P", "PA", "CMYK"):
img = img.convert("RGBA")
img_altered = True
w, h = img.size
info = RasterImageInfo()
iccp = None
if "icc_profile" in img.info:
if is_iccp_valid(img.info["icc_profile"], filename):
iccp = img.info["icc_profile"]
if img_raw_data is not None and not img_altered:
# if we can use the original image bytes directly we do (JPEG and group4 TIFF only):
if img.format == "JPEG" and image_filter == "DCTDecode":
if img.mode in ("RGB", "RGBA"):
dpn, bpc, colspace = 3, 8, "DeviceRGB"
elif img.mode == "CMYK":
dpn, bpc, colspace = 4, 8, "DeviceCMYK"
jpeg_inverted = True
if img.mode == "L":
dpn, bpc, colspace = 1, 8, "DeviceGray"
img_raw_data.seek(0)
info.update(
{
"data": img_raw_data.read(),
"w": w,
"h": h,
"cs": colspace,
"iccp": iccp,
"dpn": dpn,
"bpc": bpc,
"f": image_filter,
"inverted": jpeg_inverted,
"dp": f"/Predictor 15 /Colors {dpn} /Columns {w}",
}
)
return info
# We can directly copy the data out of a CCITT Group 4 encoded TIFF, if it
# only contains a single strip
if (
img.format == "TIFF"
and image_filter == "CCITTFaxDecode"
and img.info["compression"] == "group4"
and len(img.tag_v2[TiffImagePlugin.STRIPOFFSETS]) == 1
and len(img.tag_v2[TiffImagePlugin.STRIPBYTECOUNTS]) == 1
):
photo = img.tag_v2[TiffImagePlugin.PHOTOMETRIC_INTERPRETATION]
inverted = False
if photo == 0:
inverted = True
elif photo != 1:
raise ValueError(
f"unsupported photometric interpretation for g4 tiff: {photo}"
)
offset, length = ccitt_payload_location_from_pil(img)
img_raw_data.seek(offset)
ccittrawdata = img_raw_data.read(length)
fillorder = img.tag_v2.get(TiffImagePlugin.FILLORDER)
if fillorder is None or fillorder == 1:
# no FillOrder or msb-to-lsb: nothing to do
pass
elif fillorder == 2:
# lsb-to-msb: reverse bits of each byte
ccittrawdata = bytearray(ccittrawdata)
for i, n in enumerate(ccittrawdata):
ccittrawdata[i] = TIFFBitRevTable[n]
ccittrawdata = bytes(ccittrawdata)
else:
raise ValueError(f"unsupported FillOrder: {fillorder}")
dpn, bpc, colspace = 1, 1, "DeviceGray"
info.update(
{
"data": ccittrawdata,
"w": w,
"h": h,
"iccp": None,
"dpn": dpn,
"cs": colspace,
"bpc": bpc,
"f": image_filter,
"inverted": jpeg_inverted,
"dp": f"/BlackIs1 {str(not inverted).lower()} /Columns {w} /K -1 /Rows {h}",
}
)
return info
# garbage collection
img_raw_data = None
if img.mode == "1":
dpn, bpc, colspace = 1, 1, "DeviceGray"
info["data"] = _to_data(img, image_filter)
elif img.mode == "L":
dpn, bpc, colspace = 1, 8, "DeviceGray"
info["data"] = _to_data(img, image_filter)
elif img.mode == "LA":
dpn, bpc, colspace = 1, 8, "DeviceGray"
alpha_channel = slice(1, None, 2)
info["data"] = _to_data(img, image_filter, remove_slice=alpha_channel)
if _has_alpha(img, alpha_channel) and image_filter not in (
"DCTDecode",
"JPXDecode",
):
info["smask"] = _to_data(img, image_filter, select_slice=alpha_channel)
elif img.mode == "P":
dpn, bpc, colspace = 1, 8, "Indexed"
info["data"] = _to_data(img, image_filter)
info["pal"] = img.palette.palette
# check if the P image has transparency
if img.info.get("transparency", None) is not None and image_filter not in (
"DCTDecode",
"JPXDecode",
):
# convert to RGBA to get the alpha channel for creating the smask
info["smask"] = _to_data(
img.convert("RGBA"), image_filter, select_slice=slice(3, None, 4)
)
elif img.mode == "PA":
dpn, bpc, colspace = 1, 8, "Indexed"
info["pal"] = img.palette.palette
alpha_channel = slice(1, None, 2)
info["data"] = _to_data(img, image_filter, remove_slice=alpha_channel)
if _has_alpha(img, alpha_channel) and image_filter not in (
"DCTDecode",
"JPXDecode",
):
info["smask"] = _to_data(img, image_filter, select_slice=alpha_channel)
elif img.mode == "CMYK":
dpn, bpc, colspace = 4, 8, "DeviceCMYK"
info["data"] = _to_data(img, image_filter)
elif img.mode == "RGB":
dpn, bpc, colspace = 3, 8, "DeviceRGB"
info["data"] = _to_data(img, image_filter)
else: # RGBA image
dpn, bpc, colspace = 3, 8, "DeviceRGB"
alpha_channel = slice(3, None, 4)
info["data"] = _to_data(img, image_filter, remove_slice=alpha_channel)
if _has_alpha(img, alpha_channel) and image_filter not in (
"DCTDecode",
"JPXDecode",
):
info["smask"] = _to_data(img, image_filter, select_slice=alpha_channel)
dp = f"/Predictor 15 /Colors {dpn} /Columns {w}"
if img.mode == "1":
dp = f"/BlackIs1 true /Columns {w} /K -1 /Rows {h}"
if not is_pil_img:
if keep_bytes_io_open:
img.fp = None # cf. issue #881
else:
img.close()
info.update(
{
"w": w,
"h": h,
"cs": colspace,
"iccp": iccp,
"bpc": bpc,
"dpn": dpn,
"f": image_filter,
"inverted": jpeg_inverted,
"dp": dp,
}
)
return info
class temp_attr:
"""
temporary change the attribute of an object using a context manager
"""
def __init__(self, obj, field, value):
self.obj = obj
self.field = field
self.value = value
def __enter__(self):
self.exists = False
if hasattr(self.obj, self.field):
self.exists = True
self.old_value = getattr(self.obj, self.field)
setattr(self.obj, self.field, self.value)
def __exit__(self, exctype, excinst, exctb):
if self.exists:
setattr(self.obj, self.field, self.old_value)
else:
delattr(self.obj, self.field)
def ccitt_payload_location_from_pil(img):
"""
returns the byte offset and length of the CCITT payload in the original TIFF data
"""
# assert(img.info["compression"] == "group4")
# Read the TIFF tags to find the offset(s) of the compressed data strips.
strip_offsets = img.tag_v2[TiffImagePlugin.STRIPOFFSETS]
strip_bytes = img.tag_v2[TiffImagePlugin.STRIPBYTECOUNTS]
# PIL always seems to create a single strip even for very large TIFFs when
# it saves images, so assume we only have to read a single strip.
# A test ~10 GPixel image was still encoded as a single strip. Just to be
# safe check throw an error if there is more than one offset.
if len(strip_offsets) != 1 or len(strip_bytes) != 1:
raise NotImplementedError(
"Transcoding multiple strips not supported by the PDF format"
)
(offset,), (length,) = strip_offsets, strip_bytes
return offset, length
def transcode_monochrome(img):
"""
Convert the open PIL.Image imgdata to compressed CCITT Group4 data.
"""
# Convert the image to Group 4 in memory. If libtiff is not installed and
# Pillow is not compiled against it, .save() will raise an exception.
newimgio = BytesIO()
# we create a whole new PIL image or otherwise it might happen with some
# input images, that libtiff fails an assert and the whole process is
# killed by a SIGABRT:
img2 = Image.frombytes(img.mode, img.size, img.tobytes())
# Since version 8.3.0 Pillow limits strips to 64 KB. Since PDF only
# supports single strip CCITT Group4 payloads, we have to coerce it back
# into putting everything into a single strip. Thanks to Andrew Murray for
# the hack.
#
# Since version 8.4.0 Pillow allows us to modify the strip size explicitly
tmp_strip_size = (img.size[0] + 7) // 8 * img.size[1]
if hasattr(TiffImagePlugin, "STRIP_SIZE"):
# we are using Pillow 8.4.0 or later
with temp_attr(TiffImagePlugin, "STRIP_SIZE", tmp_strip_size):
img2.save(newimgio, format="TIFF", compression="group4")
else:
# only needed for Pillow 8.3.x but works for versions before that as
# well
pillow__getitem__ = TiffImagePlugin.ImageFileDirectory_v2.__getitem__
def __getitem__(self, tag):
overrides = {
TiffImagePlugin.ROWSPERSTRIP: img.size[1],
TiffImagePlugin.STRIPBYTECOUNTS: [tmp_strip_size],
TiffImagePlugin.STRIPOFFSETS: [0],
}
return overrides.get(tag, pillow__getitem__(self, tag))
with temp_attr(
TiffImagePlugin.ImageFileDirectory_v2, "__getitem__", __getitem__
):
img2.save(newimgio, format="TIFF", compression="group4")
# Open new image in memory
newimgio.seek(0)
newimg = Image.open(newimgio)
offset, length = ccitt_payload_location_from_pil(newimg)
newimgio.seek(offset)
return newimgio.read(length)
def _to_data(img, image_filter, **kwargs):
if image_filter == "FlateDecode":
return _to_zdata(img, **kwargs)
if image_filter == "CCITTFaxDecode":
return transcode_monochrome(img)
if img.mode == "LA":
img = img.convert("L")
if img.mode == "RGBA":
img = img.convert("RGB")
if image_filter == "DCTDecode":
compressed_bytes = BytesIO()
img.save(compressed_bytes, format="JPEG")
return compressed_bytes.getvalue()
if image_filter == "JPXDecode":
compressed_bytes = BytesIO()
img.save(compressed_bytes, format="JPEG2000")
return compressed_bytes.getvalue()
raise FPDFException(f'Unsupported image filter: "{image_filter}"')
def _to_zdata(img, remove_slice=None, select_slice=None):
data = bytearray(img.tobytes())
if remove_slice:
del data[remove_slice]
if select_slice:
data = data[select_slice]
# Left-padding every row with a single zero:
if img.mode == "1":
row_size = ceil(img.size[0] / 8)
else:
channels_count = len(data) // (img.size[0] * img.size[1])
row_size = img.size[0] * channels_count
data_with_padding = bytearray()
for i in range(0, len(data), row_size):
data_with_padding.extend(b"\0")
data_with_padding.extend(data[i : i + row_size])
return zlib.compress(data_with_padding, level=SETTINGS.compression_level)
def _has_alpha(img, alpha_channel):
alpha = bytearray(img.tobytes())[alpha_channel]
return any(c != 255 for c in alpha)
Functions
def ccitt_payload_location_from_pil(img)
-
returns the byte offset and length of the CCITT payload in the original TIFF data
Expand source code Browse git
def ccitt_payload_location_from_pil(img): """ returns the byte offset and length of the CCITT payload in the original TIFF data """ # assert(img.info["compression"] == "group4") # Read the TIFF tags to find the offset(s) of the compressed data strips. strip_offsets = img.tag_v2[TiffImagePlugin.STRIPOFFSETS] strip_bytes = img.tag_v2[TiffImagePlugin.STRIPBYTECOUNTS] # PIL always seems to create a single strip even for very large TIFFs when # it saves images, so assume we only have to read a single strip. # A test ~10 GPixel image was still encoded as a single strip. Just to be # safe check throw an error if there is more than one offset. if len(strip_offsets) != 1 or len(strip_bytes) != 1: raise NotImplementedError( "Transcoding multiple strips not supported by the PDF format" ) (offset,), (length,) = strip_offsets, strip_bytes return offset, length
def get_img_info(filename, img=None, image_filter='AUTO', dims=None)
-
Args
filename
- in a format that can be passed to load_image
img
- optional
bytes
,BytesIO
orPIL.Image.Image
instance image_filter
:str
- one of the SUPPORTED_IMAGE_FILTERS
Expand source code Browse git
def get_img_info(filename, img=None, image_filter="AUTO", dims=None): """ Args: filename: in a format that can be passed to load_image img: optional `bytes`, `BytesIO` or `PIL.Image.Image` instance image_filter (str): one of the SUPPORTED_IMAGE_FILTERS """ if Image is None: raise EnvironmentError("Pillow not available - fpdf2 cannot insert images") is_pil_img = True keep_bytes_io_open = False # Flag to check whether a cmyk image is jpeg or not, if set to True the decode array # is inverted in output.py jpeg_inverted = False img_raw_data = None if not img or isinstance(img, (Path, str)): img_raw_data = load_image(filename) img = Image.open(img_raw_data) is_pil_img = False elif not isinstance(img, Image.Image): keep_bytes_io_open = isinstance(img, BytesIO) img_raw_data = BytesIO(img) if isinstance(img, bytes) else img img = Image.open(img_raw_data) is_pil_img = False img_altered = False if dims: img = img.resize(dims, resample=RESAMPLE) img_altered = True if image_filter == "AUTO": # Very simple logic for now: if img.format == "JPEG": image_filter = "DCTDecode" elif img.mode == "1" and hasattr(Image.core, "libtiff_support_custom_tags"): # The 2nd condition prevents from running in a bug sometimes, # cf. test_transcode_monochrome_and_libtiff_support_custom_tags() image_filter = "CCITTFaxDecode" else: image_filter = "FlateDecode" if img.mode in ("P", "PA") and image_filter != "FlateDecode": img = img.convert("RGBA") if img.mode not in ("1", "L", "LA", "RGB", "RGBA", "P", "PA", "CMYK"): img = img.convert("RGBA") img_altered = True w, h = img.size info = RasterImageInfo() iccp = None if "icc_profile" in img.info: if is_iccp_valid(img.info["icc_profile"], filename): iccp = img.info["icc_profile"] if img_raw_data is not None and not img_altered: # if we can use the original image bytes directly we do (JPEG and group4 TIFF only): if img.format == "JPEG" and image_filter == "DCTDecode": if img.mode in ("RGB", "RGBA"): dpn, bpc, colspace = 3, 8, "DeviceRGB" elif img.mode == "CMYK": dpn, bpc, colspace = 4, 8, "DeviceCMYK" jpeg_inverted = True if img.mode == "L": dpn, bpc, colspace = 1, 8, "DeviceGray" img_raw_data.seek(0) info.update( { "data": img_raw_data.read(), "w": w, "h": h, "cs": colspace, "iccp": iccp, "dpn": dpn, "bpc": bpc, "f": image_filter, "inverted": jpeg_inverted, "dp": f"/Predictor 15 /Colors {dpn} /Columns {w}", } ) return info # We can directly copy the data out of a CCITT Group 4 encoded TIFF, if it # only contains a single strip if ( img.format == "TIFF" and image_filter == "CCITTFaxDecode" and img.info["compression"] == "group4" and len(img.tag_v2[TiffImagePlugin.STRIPOFFSETS]) == 1 and len(img.tag_v2[TiffImagePlugin.STRIPBYTECOUNTS]) == 1 ): photo = img.tag_v2[TiffImagePlugin.PHOTOMETRIC_INTERPRETATION] inverted = False if photo == 0: inverted = True elif photo != 1: raise ValueError( f"unsupported photometric interpretation for g4 tiff: {photo}" ) offset, length = ccitt_payload_location_from_pil(img) img_raw_data.seek(offset) ccittrawdata = img_raw_data.read(length) fillorder = img.tag_v2.get(TiffImagePlugin.FILLORDER) if fillorder is None or fillorder == 1: # no FillOrder or msb-to-lsb: nothing to do pass elif fillorder == 2: # lsb-to-msb: reverse bits of each byte ccittrawdata = bytearray(ccittrawdata) for i, n in enumerate(ccittrawdata): ccittrawdata[i] = TIFFBitRevTable[n] ccittrawdata = bytes(ccittrawdata) else: raise ValueError(f"unsupported FillOrder: {fillorder}") dpn, bpc, colspace = 1, 1, "DeviceGray" info.update( { "data": ccittrawdata, "w": w, "h": h, "iccp": None, "dpn": dpn, "cs": colspace, "bpc": bpc, "f": image_filter, "inverted": jpeg_inverted, "dp": f"/BlackIs1 {str(not inverted).lower()} /Columns {w} /K -1 /Rows {h}", } ) return info # garbage collection img_raw_data = None if img.mode == "1": dpn, bpc, colspace = 1, 1, "DeviceGray" info["data"] = _to_data(img, image_filter) elif img.mode == "L": dpn, bpc, colspace = 1, 8, "DeviceGray" info["data"] = _to_data(img, image_filter) elif img.mode == "LA": dpn, bpc, colspace = 1, 8, "DeviceGray" alpha_channel = slice(1, None, 2) info["data"] = _to_data(img, image_filter, remove_slice=alpha_channel) if _has_alpha(img, alpha_channel) and image_filter not in ( "DCTDecode", "JPXDecode", ): info["smask"] = _to_data(img, image_filter, select_slice=alpha_channel) elif img.mode == "P": dpn, bpc, colspace = 1, 8, "Indexed" info["data"] = _to_data(img, image_filter) info["pal"] = img.palette.palette # check if the P image has transparency if img.info.get("transparency", None) is not None and image_filter not in ( "DCTDecode", "JPXDecode", ): # convert to RGBA to get the alpha channel for creating the smask info["smask"] = _to_data( img.convert("RGBA"), image_filter, select_slice=slice(3, None, 4) ) elif img.mode == "PA": dpn, bpc, colspace = 1, 8, "Indexed" info["pal"] = img.palette.palette alpha_channel = slice(1, None, 2) info["data"] = _to_data(img, image_filter, remove_slice=alpha_channel) if _has_alpha(img, alpha_channel) and image_filter not in ( "DCTDecode", "JPXDecode", ): info["smask"] = _to_data(img, image_filter, select_slice=alpha_channel) elif img.mode == "CMYK": dpn, bpc, colspace = 4, 8, "DeviceCMYK" info["data"] = _to_data(img, image_filter) elif img.mode == "RGB": dpn, bpc, colspace = 3, 8, "DeviceRGB" info["data"] = _to_data(img, image_filter) else: # RGBA image dpn, bpc, colspace = 3, 8, "DeviceRGB" alpha_channel = slice(3, None, 4) info["data"] = _to_data(img, image_filter, remove_slice=alpha_channel) if _has_alpha(img, alpha_channel) and image_filter not in ( "DCTDecode", "JPXDecode", ): info["smask"] = _to_data(img, image_filter, select_slice=alpha_channel) dp = f"/Predictor 15 /Colors {dpn} /Columns {w}" if img.mode == "1": dp = f"/BlackIs1 true /Columns {w} /K -1 /Rows {h}" if not is_pil_img: if keep_bytes_io_open: img.fp = None # cf. issue #881 else: img.close() info.update( { "w": w, "h": h, "cs": colspace, "iccp": iccp, "bpc": bpc, "dpn": dpn, "f": image_filter, "inverted": jpeg_inverted, "dp": dp, } ) return info
def get_svg_info(filename, img, image_cache)
-
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def get_svg_info(filename, img, image_cache): svg = SVGObject(img.getvalue(), image_cache=image_cache) if svg.viewbox: _, _, w, h = svg.viewbox else: w = h = 0.0 if svg.width: w = svg.width if svg.height: h = svg.height info = VectorImageInfo(data=svg, w=w, h=h) return filename, svg, info
def is_iccp_valid(iccp, filename)
-
Checks the validity of an ICC profile
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def is_iccp_valid(iccp, filename): "Checks the validity of an ICC profile" try: profile = ImageCms.getOpenProfile(BytesIO(iccp)) except ImageCms.PyCMSError: LOGGER.info("Invalid ICC Profile in file %s", filename) return False color_space = profile.profile.xcolor_space.strip() if color_space not in ("GRAY", "RGB"): LOGGER.info( "Unsupported color space %s in ICC Profile of file %s - cf. issue #711", color_space, filename, ) return False return True
def load_image(filename)
-
This method is used to load external resources, such as images. It is automatically called when resource added to document by
fpdf.FPDF.image()
. It always return a BytesIO buffer.Expand source code Browse git
def load_image(filename): """ This method is used to load external resources, such as images. It is automatically called when resource added to document by `fpdf.FPDF.image()`. It always return a BytesIO buffer. """ # if a bytesio instance is passed in, use it as is. if isinstance(filename, BytesIO): return filename if isinstance(filename, Path): filename = str(filename) # by default loading from network is allowed for all images if filename.startswith(("http://", "https://")): # disabling bandit & semgrep rules as permitted schemes are whitelisted: # nosemgrep: python.lang.security.audit.dynamic-urllib-use-detected.dynamic-urllib-use-detected with urlopen(filename) as url_file: # nosec B310 return BytesIO(url_file.read()) elif filename.startswith("data:"): return _decode_base64_image(filename) with open(filename, "rb") as local_file: return BytesIO(local_file.read())
def preload_image(image_cache: ImageCache, name, dims=None)
-
Read an image and load it into memory.
For raster images: following this call, the image is inserted in
image_cache.images
, and following calls toFPDF.image()
will re-use the same cached values, without re-reading the image.For vector images: the data is loaded and the metadata extracted.
Args
image_cache
- an
ImageCache
instance, usually the.image_cache
attribute of aFPDF
instance. name
- either a string representing a file path to an image, an URL to an image,
an io.BytesIO, or a instance of
PIL.Image.Image
. dims
:Tuple[float]
- optional dimensions as a tuple (width, height) to resize the image (raster only) before storing it in the PDF.
Returns: A tuple, consisting of 3 values: the name, the image data, and an instance of a subclass of
ImageInfo
.Expand source code Browse git
def preload_image(image_cache: ImageCache, name, dims=None): """ Read an image and load it into memory. For raster images: following this call, the image is inserted in `image_cache.images`, and following calls to `FPDF.image()` will re-use the same cached values, without re-reading the image. For vector images: the data is loaded and the metadata extracted. Args: image_cache: an `ImageCache` instance, usually the `.image_cache` attribute of a `FPDF` instance. name: either a string representing a file path to an image, an URL to an image, an io.BytesIO, or a instance of `PIL.Image.Image`. dims (Tuple[float]): optional dimensions as a tuple (width, height) to resize the image (raster only) before storing it in the PDF. Returns: A tuple, consisting of 3 values: the name, the image data, and an instance of a subclass of `ImageInfo`. """ # Identify and load SVG data: if str(name).endswith(".svg"): return get_svg_info(name, load_image(str(name)), image_cache=image_cache) if isinstance(name, bytes) and _is_svg(name.strip()): return get_svg_info(name, io.BytesIO(name), image_cache=image_cache) if isinstance(name, io.BytesIO) and _is_svg(name.getvalue().strip()): return get_svg_info("vector_image", name, image_cache=image_cache) # Load raster data. if isinstance(name, str): img = None elif isinstance(name, Image.Image): bytes_ = name.tobytes() img_hash = hashlib.new("md5", usedforsecurity=False) # nosec B324 img_hash.update(bytes_) name, img = img_hash.hexdigest(), name elif isinstance(name, (bytes, io.BytesIO)): bytes_ = name.getvalue() if isinstance(name, io.BytesIO) else name bytes_ = bytes_.strip() img_hash = hashlib.new("md5", usedforsecurity=False) # nosec B324 img_hash.update(bytes_) name, img = img_hash.hexdigest(), name else: name, img = str(name), name info = image_cache.images.get(name) if info: info["usages"] += 1 else: info = get_img_info(name, img, image_cache.image_filter, dims) info["i"] = len(image_cache.images) + 1 info["usages"] = 1 info["iccp_i"] = None iccp = info.get("iccp") if iccp: LOGGER.debug( "ICC profile found for image %s - It will be inserted in the PDF document", name, ) if iccp in image_cache.icc_profiles: info["iccp_i"] = image_cache.icc_profiles[iccp] else: iccp_i = len(image_cache.icc_profiles) image_cache.icc_profiles[iccp] = iccp_i info["iccp_i"] = iccp_i info["iccp"] = None image_cache.images[name] = info return name, img, info
def transcode_monochrome(img)
-
Convert the open PIL.Image imgdata to compressed CCITT Group4 data.
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def transcode_monochrome(img): """ Convert the open PIL.Image imgdata to compressed CCITT Group4 data. """ # Convert the image to Group 4 in memory. If libtiff is not installed and # Pillow is not compiled against it, .save() will raise an exception. newimgio = BytesIO() # we create a whole new PIL image or otherwise it might happen with some # input images, that libtiff fails an assert and the whole process is # killed by a SIGABRT: img2 = Image.frombytes(img.mode, img.size, img.tobytes()) # Since version 8.3.0 Pillow limits strips to 64 KB. Since PDF only # supports single strip CCITT Group4 payloads, we have to coerce it back # into putting everything into a single strip. Thanks to Andrew Murray for # the hack. # # Since version 8.4.0 Pillow allows us to modify the strip size explicitly tmp_strip_size = (img.size[0] + 7) // 8 * img.size[1] if hasattr(TiffImagePlugin, "STRIP_SIZE"): # we are using Pillow 8.4.0 or later with temp_attr(TiffImagePlugin, "STRIP_SIZE", tmp_strip_size): img2.save(newimgio, format="TIFF", compression="group4") else: # only needed for Pillow 8.3.x but works for versions before that as # well pillow__getitem__ = TiffImagePlugin.ImageFileDirectory_v2.__getitem__ def __getitem__(self, tag): overrides = { TiffImagePlugin.ROWSPERSTRIP: img.size[1], TiffImagePlugin.STRIPBYTECOUNTS: [tmp_strip_size], TiffImagePlugin.STRIPOFFSETS: [0], } return overrides.get(tag, pillow__getitem__(self, tag)) with temp_attr( TiffImagePlugin.ImageFileDirectory_v2, "__getitem__", __getitem__ ): img2.save(newimgio, format="TIFF", compression="group4") # Open new image in memory newimgio.seek(0) newimg = Image.open(newimgio) offset, length = ccitt_payload_location_from_pil(newimg) newimgio.seek(offset) return newimgio.read(length)
Classes
class ImageSettings (compression_level: int = -1)
-
ImageSettings(compression_level: int = -1)
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@dataclass class ImageSettings: # Passed to zlib.compress() - In range 0-9 - Default is currently equivalent to 6: compression_level: int = -1
Class variables
var compression_level : int
class temp_attr (obj, field, value)
-
temporary change the attribute of an object using a context manager
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class temp_attr: """ temporary change the attribute of an object using a context manager """ def __init__(self, obj, field, value): self.obj = obj self.field = field self.value = value def __enter__(self): self.exists = False if hasattr(self.obj, self.field): self.exists = True self.old_value = getattr(self.obj, self.field) setattr(self.obj, self.field, self.value) def __exit__(self, exctype, excinst, exctb): if self.exists: setattr(self.obj, self.field, self.old_value) else: delattr(self.obj, self.field)