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| -rw-r--r-- | src/icc.py | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/src/icc.py b/src/icc.py new file mode 100644 index 0000000..705d135 --- /dev/null +++ b/src/icc.py @@ -0,0 +1,95 @@ +#!/usr/bin/env python3 + +# Copyright © 2014 Mattias Andrée (maandree@member.fsf.org) +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. +# +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + + +def load_icc(pathname): + ''' + Load ICC profile from a file + + @param pathname The ICC profile file + @return Function to invoke, parameterless, to apply the ICC profile to the colour curves + ''' + MLUT_TAG = 0x6d4c5554 + VCGT_TAG = 0x76636774 + + def make_f(R_curve, G_curve, B_curve): + pass ## TODO + + int_ = lambda bs : sum([bs[len(bs) - 1 - i] << (8 * i) for i in range(len(bs))]) + def read(n): + if len(content) < n: + raise Except("Premature end of file: %s" % pathname) + rc, content[:] = content[:n], content[n:] + return rc + + content = None + with open(pathname, 'rb') as file: + content = file.read() + content = list(content) + read(128) + + n_tags, ptr = int_(read(4)), 128 + 4 + for i_tag in range(n_tags): + tag_name = int_(read(4)) + tag_offset = int_(read(4)) + tag_size = int_(read(4)) + ptr += 3 * 4 + if tag_name == MLUT_TAG: + read(tag_offset - ptr) + R_curve, G_curve, B_curve = [], [], [] + for i in range(256): R_curve.append(int_(read(2))) + for i in range(256): G_curve.append(int_(read(2))) + for i in range(256): B_curve.append(int_(read(2))) + return make_f(R_curve, G_curve, B_curve) + elif tag_name == VCGT_TAG: + read(tag_offset - ptr) + tag_name = int_(read(4)) + if not tag_name == VCGT_TAG: + break + read(4) + gamma_type = int_(read(4)) + if gamma_type == 0: + n_channels = int_(read(2)) + n_entries = int_(read(2)) + entry_size = int_(read(2)) + if tag_size == 1584: + n_channels, n_entries, entry_size = 3, 256, 2 + if not n_channels == 3: # assuming sRGB + break + int__ = lambda m : float(int(int_(read(m)) * 8 ** (2 - m))) + for i in range(n_entries): R_curve.append(int__(entry_size)) + for i in range(n_entries): G_curve.append(int__(entry_size)) + for i in range(n_entries): B_curve.append(int__(entry_size)) + return make_f(R_curve, G_curve, B_curve) + elif gamma_type == 1: + r_gamma = int_(read(4)) / 65535 + r_min = int_(read(4)) / 65535 + r_max = int_(read(4)) / 65535 + g_gamma = int_(read(4)) / 65535 + g_min = int_(read(4)) / 65535 + g_max = int_(read(4)) / 65535 + b_gamma = int_(read(4)) / 65535 + b_min = int_(read(4)) / 65535 + b_max = int_(read(4)) / 65535 + def f(): + gamma(r_gamma, g_gamma, b_gamma) + rgb_limits(r_min, r_max, g_min, g_max, b_min, b_max) + return f + break + + raise Exception("Unsupported ICC profile file") + |