from hachoir_metadata.metadata import (registerExtractor,
Metadata, RootMetadata, MultipleMetadata)
from hachoir_parser.image import (
BmpFile, IcoFile, PcxFile, GifFile, PngFile, TiffFile,
XcfFile, TargaFile, WMF_File, PsdFile)
from hachoir_parser.image.png import getBitsPerPixel as pngBitsPerPixel
from hachoir_parser.image.xcf import XcfProperty
from hachoir_core.i18n import _
from hachoir_core.error import HACHOIR_ERRORS
from hachoir_metadata.safe import fault_tolerant
def computeComprRate(meta, compr_size):
"""
Compute image compression rate. Skip size of color palette, focus on
image pixels. Original size is width x height x bpp. Compressed size
is an argument (in bits).
Set "compr_data" with a string like "1.52x".
"""
if not meta.has("width") \
or not meta.has("height") \
or not meta.has("bits_per_pixel"):
return
if not compr_size:
return
orig_size = meta.get('width') * meta.get('height') * meta.get('bits_per_pixel')
meta.compr_rate = float(orig_size) / compr_size
class BmpMetadata(RootMetadata):
def extract(self, image):
if "header" not in image:
return
hdr = image["header"]
self.width = hdr["width"].value
self.height = hdr["height"].value
bpp = hdr["bpp"].value
if bpp:
if bpp <= 8 and "used_colors" in hdr:
self.nb_colors = hdr["used_colors"].value
self.bits_per_pixel = bpp
self.compression = hdr["compression"].display
self.format_version = u"Microsoft Bitmap version %s" % hdr.getFormatVersion()
if "pixels" in image:
computeComprRate(self, image["pixels"].size)
class TiffMetadata(RootMetadata):
key_to_attr = {
"img_width": "width",
"img_height": "width",
# TODO: Enable that (need link to value)
# "description": "comment",
# "doc_name": "title",
# "orientation": "image_orientation",
}
def extract(self, tiff):
if "ifd" in tiff:
self.useIFD(tiff["ifd"])
def useIFD(self, ifd):
for field in ifd:
key = field.name
try:
attrname = self.key_to_attr[field.name]
except KeyError:
continue
if "value" not in field:
continue
value = field["value"].value
setattr(self, attrname, value)
class IcoMetadata(MultipleMetadata):
color_to_bpp = {
2: 1,
16: 4,
256: 8
}
def extract(self, icon):
for index, header in enumerate(icon.array("icon_header")):
image = Metadata(self)
# Read size and colors from header
image.width = header["width"].value
image.height = header["height"].value
bpp = header["bpp"].value
nb_colors = header["nb_color"].value
if nb_colors != 0:
image.nb_colors = nb_colors
if bpp == 0 and nb_colors in self.color_to_bpp:
bpp = self.color_to_bpp[nb_colors]
elif bpp == 0:
bpp = 8
image.bits_per_pixel = bpp
image.setHeader(_("Icon #%u (%sx%s)")
% (1+index, image.get("width", "?"), image.get("height", "?")))
# Read compression from data (if available)
key = "icon_data[%u]/header/codec" % index
if key in icon:
image.compression = icon[key].display
key = "icon_data[%u]/pixels" % index
if key in icon:
computeComprRate(image, icon[key].size)
# Store new image
self.addGroup("image[%u]" % index, image)
class PcxMetadata(RootMetadata):
def extract(self, pcx):
self.width = 1 + pcx["xmax"].value
self.height = 1 + pcx["ymax"].value
self.bits_per_pixel = pcx["bpp"].value
if 1 <= pcx["bpp"].value <= 8:
self.nb_colors = 2 ** pcx["bpp"].value
self.compression = _("Run-length encoding (RLE)")
self.format_version = "PCX: %s" % pcx["version"].display
if "image_data" in pcx:
computeComprRate(self, pcx["image_data"].size)
class XcfMetadata(RootMetadata):
# Map image type to bits/pixel
TYPE_TO_BPP = {0: 24, 1: 8, 2: 8}
def extract(self, xcf):
self.width = xcf["width"].value
self.height = xcf["height"].value
try:
self.bits_per_pixel = self.TYPE_TO_BPP[ xcf["type"].value ]
except KeyError:
pass
self.format_version = xcf["type"].display
self.readProperties(xcf)
@fault_tolerant
def processProperty(self, prop):
type = prop["type"].value
if type == XcfProperty.PROP_PARASITES:
for field in prop["data"]:
if "name" not in field or "data" not in field:
continue
if field["name"].value == "gimp-comment":
self.comment = field["data"].value
elif type == XcfProperty.PROP_COMPRESSION:
self.compression = prop["data/compression"].display
def readProperties(self, xcf):
for prop in xcf.array("property"):
self.processProperty(prop)
class PngMetadata(RootMetadata):
TEXT_TO_ATTR = {
"software": "producer",
}
def extract(self, png):
if "header" in png:
self.useHeader(png["header"])
if "time" in png:
try:
self.creation_date = png["time"].value
except HACHOIR_ERRORS:
pass
for comment in png.array("text"):
if "text" not in comment:
continue
keyword = comment["keyword"].value
text = comment["text"].value
try:
key = self.TEXT_TO_ATTR[keyword.lower()]
setattr(self, key, text)
except KeyError:
if keyword.lower() != "comment":
self.comment = "%s=%s" % (keyword, text)
else:
self.comment = text
compr_size = sum( data.size for data in png.array("data") )
computeComprRate(self, compr_size)
@fault_tolerant
def useHeader(self, header):
self.width = header["width"].value
self.height = header["height"].value
# Read number of colors and pixel format
if "/palette/size" in header:
nb_colors = header["/palette/size"].value // 3
else:
nb_colors = None
if not header["has_palette"].value:
if header["has_alpha"].value:
self.pixel_format = _("RGBA")
else:
self.pixel_format = _("RGB")
elif "/transparency" in header:
self.pixel_format = _("Color index with transparency")
if nb_colors:
nb_colors -= 1
else:
self.pixel_format = _("Color index")
self.bits_per_pixel = pngBitsPerPixel(header)
if nb_colors:
self.nb_colors = nb_colors
# Read compression, timestamp, etc.
self.compression = header["compression"].display
class GifMetadata(RootMetadata):
def extract(self, gif):
self.useScreen(gif["/screen"])
if self.has("bits_per_pixel"):
self.nb_colors = (1 << self.get('bits_per_pixel'))
self.compression = _("LZW")
self.format_version = "GIF version %s" % gif["header"].value[-3:]
if "comments" in gif:
for comment in gif.array("comments/comment"):
self.comment = comment.value
if "graphic_ctl/has_transp" in gif and gif["graphic_ctl/has_transp"].value:
self.pixel_format = _("Color index with transparency")
else:
self.pixel_format = _("Color index")
@fault_tolerant
def useScreen(self, screen):
self.width = screen["width"].value
self.height = screen["height"].value
self.bits_per_pixel = (1 + screen["bpp"].value)
class TargaMetadata(RootMetadata):
def extract(self, tga):
self.width = tga["width"].value
self.height = tga["height"].value
self.bits_per_pixel = tga["bpp"].value
if tga["nb_color"].value:
self.nb_colors = tga["nb_color"].value
self.compression = tga["codec"].display
if "pixels" in tga:
computeComprRate(self, tga["pixels"].size)
class WmfMetadata(RootMetadata):
def extract(self, wmf):
if wmf.isAPM():
if "amf_header/rect" in wmf:
rect = wmf["amf_header/rect"]
self.width = (rect["right"].value - rect["left"].value)
self.height = (rect["bottom"].value - rect["top"].value)
self.bits_per_pixel = 24
elif wmf.isEMF():
emf = wmf["emf_header"]
if "description" in emf:
desc = emf["description"].value
if "\0" in desc:
self.producer, self.title = desc.split("\0", 1)
else:
self.producer = desc
if emf["nb_colors"].value:
self.nb_colors = emf["nb_colors"].value
self.bits_per_pixel = 8
else:
self.bits_per_pixel = 24
self.width = emf["width_px"].value
self.height = emf["height_px"].value
class PsdMetadata(RootMetadata):
@fault_tolerant
def extract(self, psd):
self.width = psd["width"].value
self.height = psd["height"].value
self.bits_per_pixel = psd["depth"].value * psd["nb_channels"].value
self.pixel_format = psd["color_mode"].display
self.compression = psd["compression"].display
registerExtractor(IcoFile, IcoMetadata)
registerExtractor(GifFile, GifMetadata)
registerExtractor(XcfFile, XcfMetadata)
registerExtractor(TargaFile, TargaMetadata)
registerExtractor(PcxFile, PcxMetadata)
registerExtractor(BmpFile, BmpMetadata)
registerExtractor(PngFile, PngMetadata)
registerExtractor(TiffFile, TiffMetadata)
registerExtractor(WMF_File, WmfMetadata)
registerExtractor(PsdFile, PsdMetadata)
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