def get_qt_image(self):
reader = QtGui.QImageReader(self.path)
reader.setAutoTransform(False)
qt_im = reader.read()
if not qt_im or qt_im.isNull():
logger.error('Image read: %s: %s', self.path, reader.errorString())
return None
w = qt_im.width()
h = qt_im.height()
if max(w, h) > 1000:
# use Qt's scaling (not high quality) to pre-shrink large
# images
qt_im = qt_im.scaled(1000, 1000, Qt.KeepAspectRatio,
Qt.SmoothTransformation)
w = qt_im.width()
h = qt_im.height()
# pad image to 4:3 (or 3:4) aspect ratio
if w >= h:
new_h = int(0.5 + (float(w * 3) / 4.0))
new_w = int(0.5 + (float(h * 4) / 3.0))
else:
new_h = int(0.5 + (float(w * 4) / 3.0))
new_w = int(0.5 + (float(h * 3) / 4.0))
if new_w > w:
pad = (new_w - w) // 2
qt_im = qt_im.copy(-pad, 0, new_w, h)
elif new_h > h:
pad = (new_h - h) // 2
qt_im = qt_im.copy(0, -pad, w, new_h)
return qt_im
def convert(value):
if value['data'] and not value['image']:
buf = QtCore.QBuffer()
buf.setData(value['data'])
reader = QtGui.QImageReader(buf)
reader.setAutoTransform(False)
value['fmt'] = reader.format().data().decode().upper()
value['image'] = reader.read()
if value['image'].isNull():
logger.error('thumbnail: %s', reader.errorString())
value['image'] = None
# don't keep reference to what might be an entire image file
value['data'] = None
if value['image'] and not value['data']:
buf = QtCore.QBuffer()
buf.open(buf.WriteOnly)
value['fmt'] = 'JPEG'
value['image'].save(buf, value['fmt'])
value['data'] = buf.data().data()
if value['image']:
value['w'] = value['image'].width()
value['h'] = value['image'].height()
else:
value['w'] = 0
value['h'] = 0
return value
def convert(value):
if value['data'] and not value['image']:
buf = QtCore.QBuffer()
buf.setData(value['data'])
reader = QtGui.QImageReader(buf)
reader.setAutoTransform(False)
value['fmt'] = reader.format().data().decode().upper()
value['image'] = reader.read()
if value['image'].isNull():
logger.error('thumbnail: %s', reader.errorString())
value['image'] = None
if value['image']:
value['w'] = value['image'].width()
value['h'] = value['image'].height()
if value['data'] and len(value['data']) >= 60000:
# don't keep unusably large amount of data
value['data'] = None
else:
value['w'] = 0
value['h'] = 0
value['data'] = None
return value
def is_convertible(self, image):
if not image.file_type.startswith('image'):
# can only convert images
return False
return QtGui.QImageReader(image.path).canRead()
