Source code for PIL.PsdImagePlugin

#
# The Python Imaging Library
# $Id$
#
# Adobe PSD 2.5/3.0 file handling
#
# History:
# 1995-09-01 fl   Created
# 1997-01-03 fl   Read most PSD images
# 1997-01-18 fl   Fixed P and CMYK support
# 2001-10-21 fl   Added seek/tell support (for layers)
#
# Copyright (c) 1997-2001 by Secret Labs AB.
# Copyright (c) 1995-2001 by Fredrik Lundh
#
# See the README file for information on usage and redistribution.
#

__version__ = "0.4"

from . import Image, ImageFile, ImagePalette
from ._binary import i8, i16be as i16, i32be as i32

MODES = {
    # (photoshop mode, bits) -> (pil mode, required channels)
    (0, 1): ("1", 1),
    (0, 8): ("L", 1),
    (1, 8): ("L", 1),
    (2, 8): ("P", 1),
    (3, 8): ("RGB", 3),
    (4, 8): ("CMYK", 4),
    (7, 8): ("L", 1),  # FIXME: multilayer
    (8, 8): ("L", 1),  # duotone
    (9, 8): ("LAB", 3)
}


# --------------------------------------------------------------------.
# read PSD images

def _accept(prefix):
    return prefix[:4] == b"8BPS"


##
# Image plugin for Photoshop images.

[docs]class PsdImageFile(ImageFile.ImageFile): format = "PSD" format_description = "Adobe Photoshop" def _open(self): read = self.fp.read # # header s = read(26) if s[:4] != b"8BPS" or i16(s[4:]) != 1: raise SyntaxError("not a PSD file") psd_bits = i16(s[22:]) psd_channels = i16(s[12:]) psd_mode = i16(s[24:]) mode, channels = MODES[(psd_mode, psd_bits)] if channels > psd_channels: raise IOError("not enough channels") self.mode = mode self._size = i32(s[18:]), i32(s[14:]) # # color mode data size = i32(read(4)) if size: data = read(size) if mode == "P" and size == 768: self.palette = ImagePalette.raw("RGB;L", data) # # image resources self.resources = [] size = i32(read(4)) if size: # load resources end = self.fp.tell() + size while self.fp.tell() < end: signature = read(4) id = i16(read(2)) name = read(i8(read(1))) if not (len(name) & 1): read(1) # padding data = read(i32(read(4))) if (len(data) & 1): read(1) # padding self.resources.append((id, name, data)) if id == 1039: # ICC profile self.info["icc_profile"] = data # # layer and mask information self.layers = [] size = i32(read(4)) if size: end = self.fp.tell() + size size = i32(read(4)) if size: self.layers = _layerinfo(self.fp) self.fp.seek(end) # # image descriptor self.tile = _maketile(self.fp, mode, (0, 0) + self.size, channels) # keep the file open self._fp = self.fp self.frame = 1 self._min_frame = 1 @property def n_frames(self): return len(self.layers) @property def is_animated(self): return len(self.layers) > 1
[docs] def seek(self, layer): if not self._seek_check(layer): return # seek to given layer (1..max) try: name, mode, bbox, tile = self.layers[layer-1] self.mode = mode self.tile = tile self.frame = layer self.fp = self._fp return name, bbox except IndexError: raise EOFError("no such layer")
[docs] def tell(self): # return layer number (0=image, 1..max=layers) return self.frame
[docs] def load_prepare(self): # create image memory if necessary if not self.im or\ self.im.mode != self.mode or self.im.size != self.size: self.im = Image.core.fill(self.mode, self.size, 0) # create palette (optional) if self.mode == "P": Image.Image.load(self)
def _layerinfo(file): # read layerinfo block layers = [] read = file.read for i in range(abs(i16(read(2)))): # bounding box y0 = i32(read(4)) x0 = i32(read(4)) y1 = i32(read(4)) x1 = i32(read(4)) # image info info = [] mode = [] types = list(range(i16(read(2)))) if len(types) > 4: continue for i in types: type = i16(read(2)) if type == 65535: m = "A" else: m = "RGBA"[type] mode.append(m) size = i32(read(4)) info.append((m, size)) # figure out the image mode mode.sort() if mode == ["R"]: mode = "L" elif mode == ["B", "G", "R"]: mode = "RGB" elif mode == ["A", "B", "G", "R"]: mode = "RGBA" else: mode = None # unknown # skip over blend flags and extra information filler = read(12) name = "" size = i32(read(4)) combined = 0 if size: length = i32(read(4)) if length: mask_y = i32(read(4)) mask_x = i32(read(4)) mask_h = i32(read(4)) - mask_y mask_w = i32(read(4)) - mask_x file.seek(length - 16, 1) combined += length + 4 length = i32(read(4)) if length: file.seek(length, 1) combined += length + 4 length = i8(read(1)) if length: # Don't know the proper encoding, # Latin-1 should be a good guess name = read(length).decode('latin-1', 'replace') combined += length + 1 file.seek(size - combined, 1) layers.append((name, mode, (x0, y0, x1, y1))) # get tiles i = 0 for name, mode, bbox in layers: tile = [] for m in mode: t = _maketile(file, m, bbox, 1) if t: tile.extend(t) layers[i] = name, mode, bbox, tile i += 1 return layers def _maketile(file, mode, bbox, channels): tile = None read = file.read compression = i16(read(2)) xsize = bbox[2] - bbox[0] ysize = bbox[3] - bbox[1] offset = file.tell() if compression == 0: # # raw compression tile = [] for channel in range(channels): layer = mode[channel] if mode == "CMYK": layer += ";I" tile.append(("raw", bbox, offset, layer)) offset = offset + xsize*ysize elif compression == 1: # # packbits compression i = 0 tile = [] bytecount = read(channels * ysize * 2) offset = file.tell() for channel in range(channels): layer = mode[channel] if mode == "CMYK": layer += ";I" tile.append( ("packbits", bbox, offset, layer) ) for y in range(ysize): offset = offset + i16(bytecount[i:i+2]) i += 2 file.seek(offset) if offset & 1: read(1) # padding return tile # -------------------------------------------------------------------- # registry Image.register_open(PsdImageFile.format, PsdImageFile, _accept) Image.register_extension(PsdImageFile.format, ".psd")