""" Photoshop metadata parser. References: - http://www.scribd.com/doc/32900475/Photoshop-File-Formats """ from hachoir.field import (FieldSet, ParserError, UInt8, UInt16, UInt32, Float32, Enum, SubFile, String, CString, PascalString8, NullBytes, RawBytes) from hachoir.core.text_handler import textHandler, hexadecimal from hachoir.core.tools import alignValue, createDict from hachoir.parser.image.iptc import IPTC from hachoir.parser.common.win32 import PascalStringWin32 BOOL = {0: False, 1: True} class Version(FieldSet): def createFields(self): yield UInt32(self, "version") yield UInt8(self, "has_realm") yield PascalStringWin32(self, "writer_name", charset="UTF-16-BE") yield PascalStringWin32(self, "reader_name", charset="UTF-16-BE") yield UInt32(self, "file_version") size = (self.size - self.current_size) // 8 if size: yield NullBytes(self, "padding", size) class FixedFloat32(FieldSet): def createFields(self): yield UInt16(self, "int_part") yield UInt16(self, "float_part") def createValue(self): return self["int_part"].value + float(self["float_part"].value) / (1 << 16) class ResolutionInfo(FieldSet): def createFields(self): yield FixedFloat32(self, "horiz_res") yield Enum(UInt16(self, "horiz_res_unit"), {1: 'px/in', 2: 'px/cm'}) yield Enum(UInt16(self, "width_unit"), {1: 'inches', 2: 'cm', 3: 'points', 4: 'picas', 5: 'columns'}) yield FixedFloat32(self, "vert_res") yield Enum(UInt16(self, "vert_res_unit"), {1: 'px/in', 2: 'px/cm'}) yield Enum(UInt16(self, "height_unit"), {1: 'inches', 2: 'cm', 3: 'points', 4: 'picas', 5: 'columns'}) class PrintScale(FieldSet): def createFields(self): yield Enum(UInt16(self, "style"), {0: 'centered', 1: 'size to fit', 2: 'user defined'}) yield Float32(self, "x_location") yield Float32(self, "y_location") yield Float32(self, "scale") class PrintFlags(FieldSet): def createFields(self): yield Enum(UInt8(self, "labels"), BOOL) yield Enum(UInt8(self, "crop_marks"), BOOL) yield Enum(UInt8(self, "color_bars"), BOOL) yield Enum(UInt8(self, "reg_marks"), BOOL) yield Enum(UInt8(self, "negative"), BOOL) yield Enum(UInt8(self, "flip"), BOOL) yield Enum(UInt8(self, "interpolate"), BOOL) yield Enum(UInt8(self, "caption"), BOOL) yield Enum(UInt8(self, "print_flags"), BOOL) yield Enum(UInt8(self, "unknown"), BOOL) def createValue(self): return [field.name for field in self if field.value] def createDisplay(self): return ', '.join(self.value) class PrintFlags2(FieldSet): def createFields(self): yield UInt16(self, "version") yield UInt8(self, "center_crop_marks") yield UInt8(self, "reserved") yield UInt32(self, "bleed_width") yield UInt16(self, "bleed_width_scale") class GridGuides(FieldSet): def createFields(self): yield UInt32(self, "version") yield UInt32(self, "horiz_cycle", "Horizontal grid spacing, in quarter inches") yield UInt32(self, "vert_cycle", "Vertical grid spacing, in quarter inches") yield UInt32(self, "guide_count", "Number of guide resource blocks (can be 0)") class Thumbnail(FieldSet): def createFields(self): yield Enum(UInt32(self, "format"), {0: 'Raw RGB', 1: 'JPEG RGB'}) yield UInt32(self, "width", "Width of thumbnail in pixels") yield UInt32(self, "height", "Height of thumbnail in pixels") yield UInt32(self, "widthbytes", "Padded row bytes = (width * bits per pixel + 31) / 32 * 4") yield UInt32(self, "uncompressed_size", "Total size = widthbytes * height * planes") yield UInt32(self, "compressed_size", "Size after compression. Used for consistency check") yield UInt16(self, "bits_per_pixel") yield UInt16(self, "num_planes") yield SubFile(self, "thumbnail", self['compressed_size'].value, "Thumbnail (JPEG file)", mime_type="image/jpeg") class Photoshop8BIM(FieldSet): TAG_INFO = { 0x03ed: ("res_info", ResolutionInfo, "Resolution information"), 0x03f3: ("print_flag", PrintFlags, "Print flags: labels, crop marks, colour bars, etc."), 0x03f5: ("col_half_info", None, "Colour half-toning information"), 0x03f8: ("color_trans_func", None, "Colour transfer function"), 0x0404: ("iptc", IPTC, "IPTC/NAA"), 0x0406: ("jpeg_qual", None, "JPEG quality"), 0x0408: ("grid_guide", GridGuides, "Grid guides informations"), 0x0409: ("thumb_res", Thumbnail, "Thumbnail resource (PS 4.0)"), 0x0410: ("watermark", UInt8, "Watermark"), 0x040a: ("copyright_flag", UInt8, "Copyright flag"), 0x040b: ("url", None, "URL"), 0x040c: ("thumb_res2", Thumbnail, "Thumbnail resource (PS 5.0)"), 0x040d: ("glob_angle", UInt32, "Global lighting angle for effects"), 0x0411: ("icc_tagged", None, "ICC untagged (1 means intentionally untagged)"), 0x0414: ("base_layer_id", UInt32, "Base value for new layers ID's"), 0x0416: ("indexed_colors", UInt16, "Number of colors in table that are actually defined"), 0x0417: ("transparency_index", UInt16, "Index of transparent color"), 0x0419: ("glob_altitude", UInt32, "Global altitude"), 0x041a: ("slices", None, "Slices"), 0x041e: ("url_list", None, "Unicode URLs"), 0x0421: ("version", Version, "Version information"), 0x0425: ("caption_digest", None, "16-byte MD5 caption digest"), 0x0426: ("printscale", PrintScale, "Printer scaling"), 0x2710: ("print_flag2", PrintFlags2, "Print flags (2)"), } TAG_NAME = createDict(TAG_INFO, 0) CONTENT_HANDLER = createDict(TAG_INFO, 1) TAG_DESC = createDict(TAG_INFO, 2) def __init__(self, *args, **kw): FieldSet.__init__(self, *args, **kw) try: self._name, self.handler, self._description = self.TAG_INFO[ self["tag"].value] except KeyError: self.handler = None size = self["size"] self._size = size.address + size.size + alignValue(size.value, 2) * 8 def createFields(self): yield String(self, "signature", 4, "8BIM signature", charset="ASCII") if self["signature"].value != "8BIM": raise ParserError( "Stream doesn't look like 8BIM item (wrong signature)!") yield textHandler(UInt16(self, "tag"), hexadecimal) if self.stream.readBytes(self.absolute_address + self.current_size, 4) != b"\0\0\0\0": yield PascalString8(self, "name") size = 2 + (self["name"].size // 8) % 2 yield NullBytes(self, "name_padding", size) else: yield String(self, "name", 4, strip="\0") yield UInt16(self, "size") size = alignValue(self["size"].value, 2) if not size: return if self.handler: if issubclass(self.handler, FieldSet): yield self.handler(self, "content", size=size * 8) else: yield self.handler(self, "content") else: yield RawBytes(self, "content", size) class PhotoshopMetadata(FieldSet): def createFields(self): yield CString(self, "signature", "Photoshop version") if self["signature"].value == "Photoshop 3.0": while not self.eof: yield Photoshop8BIM(self, "item[]") else: size = (self._size - self.current_size) // 8 yield RawBytes(self, "rawdata", size)