Source code for PIL.ImImagePlugin

#
# The Python Imaging Library.
# $Id$
#
# IFUNC IM file handling for PIL
#
# history:
# 1995-09-01 fl   Created.
# 1997-01-03 fl   Save palette images
# 1997-01-08 fl   Added sequence support
# 1997-01-23 fl   Added P and RGB save support
# 1997-05-31 fl   Read floating point images
# 1997-06-22 fl   Save floating point images
# 1997-08-27 fl   Read and save 1-bit images
# 1998-06-25 fl   Added support for RGB+LUT images
# 1998-07-02 fl   Added support for YCC images
# 1998-07-15 fl   Renamed offset attribute to avoid name clash
# 1998-12-29 fl   Added I;16 support
# 2001-02-17 fl   Use 're' instead of 'regex' (Python 2.1) (0.7)
# 2003-09-26 fl   Added LA/PA support
#
# Copyright (c) 1997-2003 by Secret Labs AB.
# Copyright (c) 1995-2001 by Fredrik Lundh.
#
# See the README file for information on usage and redistribution.
#


import re
from . import Image, ImageFile, ImagePalette
from ._binary import i8

__version__ = "0.7"


# --------------------------------------------------------------------
# Standard tags

COMMENT = "Comment"
DATE = "Date"
EQUIPMENT = "Digitalization equipment"
FRAMES = "File size (no of images)"
LUT = "Lut"
NAME = "Name"
SCALE = "Scale (x,y)"
SIZE = "Image size (x*y)"
MODE = "Image type"

TAGS = {COMMENT: 0, DATE: 0, EQUIPMENT: 0, FRAMES: 0, LUT: 0, NAME: 0,
        SCALE: 0, SIZE: 0, MODE: 0}

OPEN = {
    # ifunc93/p3cfunc formats
    "0 1 image": ("1", "1"),
    "L 1 image": ("1", "1"),
    "Greyscale image": ("L", "L"),
    "Grayscale image": ("L", "L"),
    "RGB image": ("RGB", "RGB;L"),
    "RLB image": ("RGB", "RLB"),
    "RYB image": ("RGB", "RLB"),
    "B1 image": ("1", "1"),
    "B2 image": ("P", "P;2"),
    "B4 image": ("P", "P;4"),
    "X 24 image": ("RGB", "RGB"),
    "L 32 S image": ("I", "I;32"),
    "L 32 F image": ("F", "F;32"),
    # old p3cfunc formats
    "RGB3 image": ("RGB", "RGB;T"),
    "RYB3 image": ("RGB", "RYB;T"),
    # extensions
    "LA image": ("LA", "LA;L"),
    "RGBA image": ("RGBA", "RGBA;L"),
    "RGBX image": ("RGBX", "RGBX;L"),
    "CMYK image": ("CMYK", "CMYK;L"),
    "YCC image": ("YCbCr", "YCbCr;L"),
}

# ifunc95 extensions
for i in ["8", "8S", "16", "16S", "32", "32F"]:
    OPEN["L %s image" % i] = ("F", "F;%s" % i)
    OPEN["L*%s image" % i] = ("F", "F;%s" % i)
for i in ["16", "16L", "16B"]:
    OPEN["L %s image" % i] = ("I;%s" % i, "I;%s" % i)
    OPEN["L*%s image" % i] = ("I;%s" % i, "I;%s" % i)
for i in ["32S"]:
    OPEN["L %s image" % i] = ("I", "I;%s" % i)
    OPEN["L*%s image" % i] = ("I", "I;%s" % i)
for i in range(2, 33):
    OPEN["L*%s image" % i] = ("F", "F;%s" % i)


# --------------------------------------------------------------------
# Read IM directory

split = re.compile(br"^([A-Za-z][^:]*):[ \t]*(.*)[ \t]*$")


[docs]def number(s): try: return int(s) except ValueError: return float(s)
## # Image plugin for the IFUNC IM file format.
[docs]class ImImageFile(ImageFile.ImageFile): format = "IM" format_description = "IFUNC Image Memory" _close_exclusive_fp_after_loading = False def _open(self): # Quick rejection: if there's not an LF among the first # 100 bytes, this is (probably) not a text header. if b"\n" not in self.fp.read(100): raise SyntaxError("not an IM file") self.fp.seek(0) n = 0 # Default values self.info[MODE] = "L" self.info[SIZE] = (512, 512) self.info[FRAMES] = 1 self.rawmode = "L" while True: s = self.fp.read(1) # Some versions of IFUNC uses \n\r instead of \r\n... if s == b"\r": continue if not s or s == b'\0' or s == b'\x1A': break # FIXME: this may read whole file if not a text file s = s + self.fp.readline() if len(s) > 100: raise SyntaxError("not an IM file") if s[-2:] == b'\r\n': s = s[:-2] elif s[-1:] == b'\n': s = s[:-1] try: m = split.match(s) except re.error as v: raise SyntaxError("not an IM file") if m: k, v = m.group(1, 2) # Don't know if this is the correct encoding, # but a decent guess (I guess) k = k.decode('latin-1', 'replace') v = v.decode('latin-1', 'replace') # Convert value as appropriate if k in [FRAMES, SCALE, SIZE]: v = v.replace("*", ",") v = tuple(map(number, v.split(","))) if len(v) == 1: v = v[0] elif k == MODE and v in OPEN: v, self.rawmode = OPEN[v] # Add to dictionary. Note that COMMENT tags are # combined into a list of strings. if k == COMMENT: if k in self.info: self.info[k].append(v) else: self.info[k] = [v] else: self.info[k] = v if k in TAGS: n += 1 else: raise SyntaxError("Syntax error in IM header: " + s.decode('ascii', 'replace')) if not n: raise SyntaxError("Not an IM file") # Basic attributes self._size = self.info[SIZE] self.mode = self.info[MODE] # Skip forward to start of image data while s and s[0:1] != b'\x1A': s = self.fp.read(1) if not s: raise SyntaxError("File truncated") if LUT in self.info: # convert lookup table to palette or lut attribute palette = self.fp.read(768) greyscale = 1 # greyscale palette linear = 1 # linear greyscale palette for i in range(256): if palette[i] == palette[i+256] == palette[i+512]: if i8(palette[i]) != i: linear = 0 else: greyscale = 0 if self.mode == "L" or self.mode == "LA": if greyscale: if not linear: self.lut = [i8(c) for c in palette[:256]] else: if self.mode == "L": self.mode = self.rawmode = "P" elif self.mode == "LA": self.mode = self.rawmode = "PA" self.palette = ImagePalette.raw("RGB;L", palette) elif self.mode == "RGB": if not greyscale or not linear: self.lut = [i8(c) for c in palette] self.frame = 0 self.__offset = offs = self.fp.tell() self.__fp = self.fp # FIXME: hack if self.rawmode[:2] == "F;": # ifunc95 formats try: # use bit decoder (if necessary) bits = int(self.rawmode[2:]) if bits not in [8, 16, 32]: self.tile = [("bit", (0, 0)+self.size, offs, (bits, 8, 3, 0, -1))] return except ValueError: pass if self.rawmode in ["RGB;T", "RYB;T"]: # Old LabEye/3PC files. Would be very surprised if anyone # ever stumbled upon such a file ;-) size = self.size[0] * self.size[1] self.tile = [("raw", (0, 0)+self.size, offs, ("G", 0, -1)), ("raw", (0, 0)+self.size, offs+size, ("R", 0, -1)), ("raw", (0, 0)+self.size, offs+2*size, ("B", 0, -1))] else: # LabEye/IFUNC files self.tile = [("raw", (0, 0)+self.size, offs, (self.rawmode, 0, -1))] @property def n_frames(self): return self.info[FRAMES] @property def is_animated(self): return self.info[FRAMES] > 1
[docs] def seek(self, frame): if not self._seek_check(frame): return self.frame = frame if self.mode == "1": bits = 1 else: bits = 8 * len(self.mode) size = ((self.size[0] * bits + 7) // 8) * self.size[1] offs = self.__offset + frame * size self.fp = self.__fp self.tile = [("raw", (0, 0)+self.size, offs, (self.rawmode, 0, -1))]
[docs] def tell(self): return self.frame
# # -------------------------------------------------------------------- # Save IM files SAVE = { # mode: (im type, raw mode) "1": ("0 1", "1"), "L": ("Greyscale", "L"), "LA": ("LA", "LA;L"), "P": ("Greyscale", "P"), "PA": ("LA", "PA;L"), "I": ("L 32S", "I;32S"), "I;16": ("L 16", "I;16"), "I;16L": ("L 16L", "I;16L"), "I;16B": ("L 16B", "I;16B"), "F": ("L 32F", "F;32F"), "RGB": ("RGB", "RGB;L"), "RGBA": ("RGBA", "RGBA;L"), "RGBX": ("RGBX", "RGBX;L"), "CMYK": ("CMYK", "CMYK;L"), "YCbCr": ("YCC", "YCbCr;L") } def _save(im, fp, filename): try: image_type, rawmode = SAVE[im.mode] except KeyError: raise ValueError("Cannot save %s images as IM" % im.mode) frames = im.encoderinfo.get("frames", 1) fp.write(("Image type: %s image\r\n" % image_type).encode('ascii')) if filename: fp.write(("Name: %s\r\n" % filename).encode('ascii')) fp.write(("Image size (x*y): %d*%d\r\n" % im.size).encode('ascii')) fp.write(("File size (no of images): %d\r\n" % frames).encode('ascii')) if im.mode == "P": fp.write(b"Lut: 1\r\n") fp.write(b"\000" * (511-fp.tell()) + b"\032") if im.mode == "P": fp.write(im.im.getpalette("RGB", "RGB;L")) # 768 bytes ImageFile._save(im, fp, [("raw", (0, 0)+im.size, 0, (rawmode, 0, -1))]) # # -------------------------------------------------------------------- # Registry Image.register_open(ImImageFile.format, ImImageFile) Image.register_save(ImImageFile.format, _save) Image.register_extension(ImImageFile.format, ".im")