def get_video_frame(self):
if not cv2:
return
video = cv2.VideoCapture(self.path)
if not video.isOpened():
return
OK, cv_image = video.read()
if not OK:
return
height, width, channel = cv_image.shape
fmt = QtGui.QImage.Format_RGB888
# need to pad to 4 pixel multiple
new_width = width - (width % -4)
if channel == 4:
# assume BGRA
fmt = QtGui.QImage.Format_ARGB32
np_image = np.empty((height, new_width, channel), dtype=np.uint8)
np_image[:, :width, 0] = cv_image[:, :, 3]
np_image[:, :width, 1] = cv_image[:, :, 2]
np_image[:, :width, 2] = cv_image[:, :, 1]
np_image[:, :width, 3] = cv_image[:, :, 0]
elif channel == 3:
# assume BGR
np_image = np.empty((height, new_width, channel), dtype=np.uint8)
np_image[:, :width, 0] = cv_image[:, :, 2]
np_image[:, :width, 1] = cv_image[:, :, 1]
np_image[:, :width, 2] = cv_image[:, :, 0]
elif channel == 1:
# assume Y
channel = 3
np_image = np.empty((height, new_width, channel), dtype=np.uint8)
np_image[:, :width, 0] = cv_image[:, :, 0]
np_image[:, :width, 1] = cv_image[:, :, 0]
np_image[:, :width, 2] = cv_image[:, :, 0]
else:
return
bpl = new_width * channel
qt_im = QtGui.QImage(np_image.data, width, height, bpl, fmt)
# attach np_image so it isn't deleted until qt_im is
qt_im._data = np_image
return qt_im
def get_qt_image(self):
qt_im = QtGui.QImage(self.path)
if not qt_im or qt_im.isNull():
logger.error('Cannot read %s image data from %s', self.file_type,
self.path)
return None
# reorient if required
if self.file_type in ('image/x-canon-cr2', 'image/x-nikon-nef'):
qt_im = self.transform(qt_im,
self.metadata.orientation,
inverse=True)
w = qt_im.width()
h = qt_im.height()
if max(w, h) > 6000:
# use Qt's scaling (not high quality) to pre-shrink very
# large images, to avoid PIL "DecompressionBombWarning"
return qt_im.scaled(6000, 6000, 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))
if new_h > h:
pad = (new_h - h) // 2
qt_im = qt_im.copy(0, -pad, w, new_h)
elif new_w > w:
pad = (new_w - w) // 2
qt_im = qt_im.copy(-pad, 0, new_w, h)
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_to_jpeg(self, image):
im = QtGui.QImage(image.path)
path = self.get_temp_filename(image)
im.save(path, format='jpeg', quality=95)
self.copy_metadata(image, path)
return path
def regenerate_thumbnail(self):
with Busy():
# get Qt image first
qt_im = QtGui.QImage(self.path)
if self.file_type.startswith('video') and qt_im.isNull():
# use OpenCV to read first frame
qt_im = self.get_video_frame()
if not qt_im or qt_im.isNull():
logger.error('Cannot read %s image data from %s',
self.file_type, self.path)
return
# reorient if required
if self.file_type in ('image/x-canon-cr2', 'image/x-nikon-nef'):
qt_im = self.transform(qt_im,
self.metadata.orientation,
inverse=True)
w = qt_im.width()
h = qt_im.height()
# use Qt's scaling (not high quality) to pre-shrink very
# large images, to avoid PIL "DecompressionBombWarning"
if max(w, h) >= 6000:
qt_im = qt_im.scaled(6000, 6000, Qt.KeepAspectRatio,
Qt.SmoothTransformation)
w = qt_im.width()
h = qt_im.height()
# DCF spec says thumbnail must be 160 x 120 so pad picture
# to 4:3 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))
if new_h > h:
pad = (new_h - h) // 2
qt_im = qt_im.copy(0, -pad, w, new_h)
elif new_w > w:
pad = (new_w - w) // 2
qt_im = qt_im.copy(-pad, 0, new_w, h)
w, h = 160, 120
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)
w, h = 120, 160
fmt = 'JPEG'
if PIL:
# convert Qt image to PIL image
buf = QtCore.QBuffer()
buf.open(QtCore.QIODevice.WriteOnly)
qt_im.save(buf, 'PPM')
data = BytesIO(buf.data().data())
pil_im = PIL.open(data)
# scale PIL image
pil_im = pil_im.resize((w, h), PIL.ANTIALIAS)
# save image to memory
data = BytesIO()
pil_im.save(data, fmt)
data = data.getvalue()
else:
# scale Qt image - not as good quality as PIL
qt_im = qt_im.scaled(w, h, Qt.IgnoreAspectRatio,
Qt.SmoothTransformation)
# save image to memory
buf = QtCore.QBuffer()
buf.open(QtCore.QIODevice.WriteOnly)
qt_im.save(buf, fmt)
data = buf.data().data()
# set thumbnail
self.metadata.thumbnail = data, fmt, w, h
# reload thumbnail
self.load_thumbnail()
