"""
Low-level API that translates binary data to Python structure.
All the data structure in this subpackage inherits from one of the object
defined in :py:mod:`psd_tools.psd.base` module.
"""
from __future__ import absolute_import, unicode_literals
import logging
import attr
from .base import BaseElement
from .color_mode_data import ColorModeData
from .header import FileHeader
from .image_data import ImageData
from .image_resources import ImageResources
from .layer_and_mask import LayerAndMaskInformation
logger = logging.getLogger(__name__)
[docs]
@attr.s(repr=False, slots=True)
class PSD(BaseElement):
"""
Low-level PSD file structure that resembles the specification_.
.. _specification: https://www.adobe.com/devnet-apps/photoshop/fileformatashtml/
Example::
from psd_tools.psd import PSD
with open(input_file, 'rb') as f:
psd = PSD.read(f)
with open(output_file, 'wb') as f:
psd.write(f)
.. py:attribute:: header
See :py:class:`.FileHeader`.
.. py:attribute:: color_mode_data
See :py:class:`.ColorModeData`.
.. py:attribute:: image_resources
See :py:class:`.ImageResources`.
.. py:attribute:: layer_and_mask_information
See :py:class:`.LayerAndMaskInformation`.
.. py:attribute:: image_data
See :py:class:`.ImageData`.
"""
header = attr.ib(factory=FileHeader)
color_mode_data = attr.ib(factory=ColorModeData)
image_resources = attr.ib(factory=ImageResources)
layer_and_mask_information = attr.ib(factory=LayerAndMaskInformation)
image_data = attr.ib(factory=ImageData)
@classmethod
def read(cls, fp, encoding="macroman", **kwargs):
header = FileHeader.read(fp)
logger.debug("read %s" % header)
return cls(
header,
ColorModeData.read(fp),
ImageResources.read(fp, encoding),
LayerAndMaskInformation.read(fp, encoding, header.version),
ImageData.read(fp),
)
def write(self, fp, encoding="macroman", **kwargs):
logger.debug("writing %s" % self.header)
written = self.header.write(fp)
written += self.color_mode_data.write(fp)
written += self.image_resources.write(fp, encoding)
written += self.layer_and_mask_information.write(
fp, encoding, self.header.version, **kwargs
)
written += self.image_data.write(fp)
return written
def _iter_layers(self):
"""
Iterate over (layer_record, channel_data) pairs.
"""
layer_info = self._get_layer_info()
if layer_info is not None:
records = layer_info.layer_records
channel_data = layer_info.channel_image_data
if records is not None and channel_data is not None:
for record, channels in zip(records, channel_data):
yield record, channels
def _get_layer_info(self):
from psd_tools.constants import Tag
tagged_blocks = self.layer_and_mask_information.tagged_blocks
if tagged_blocks is not None:
for key in (Tag.LAYER_16, Tag.LAYER_32):
if key in tagged_blocks:
return tagged_blocks.get_data(key)
return self.layer_and_mask_information.layer_info