def update_frame_image(self, frame_index: int):
"""
刷新帧图象显示
:param frame_index: 帧索引
:return: None
"""
base64 = self._frame_base64_dict[frame_index]
byte_arr = QByteArray(base64)
img = QImage()
img.loadFromData(QByteArray.fromBase64(byte_arr))
pixmap = QPixmap.fromImage(img)
self.current_frame_item.setPixmap(pixmap)
self.current_frame_index = frame_index
class PreviewWindow(QWidget):
def __init__(self, parent=None):
super().__init__(parent)
self.mode = Mode.NoMode
self.image = QImage()
self.zoomed_image = QImage()
self.svgRenderer = QSvgRenderer(self)
self.zoom_scale = ZOOM_ORIGINAL_SCALE
def mode(self):
return self.mode
def set_mode(self, mode):
self.mode = mode
def load(self, data):
if self.mode == Mode.PngMode:
self.image.loadFromData(data)
self.setMinimumSize(self.image.rect().size())
elif self.mode == Mode.SvgMode:
self.svgRenderer.load(data)
self.zoom_image()
self.update()
# Public slots
def zoom_original(self):
self.set_zoom_scale(ZOOM_ORIGINAL_SCALE)
def zoom_in(self):
# new_scale = self.zoom_scale + \
# ZOOM_BIG_INCREMENT if self.zoom_scale >= ZOOM_ORIGINAL_SCALE else ZOOM_SMALL_INCREMENT
new_scale = self.zoom_scale + ZOOM_SMALL_INCREMENT
if new_scale > MAX_ZOOM_SCALE:
new_scale = MAX_ZOOM_SCALE
self.set_zoom_scale(new_scale)
def zoom_out(self):
# new_scale = self.zoom_scale - \
# ZOOM_SMALL_INCREMENT if self.zoom_scale <= ZOOM_ORIGINAL_SCALE else ZOOM_BIG_INCREMENT
new_scale = self.zoom_scale - ZOOM_SMALL_INCREMENT
if new_scale < MIN_ZOOM_SCALE:
new_scale = MIN_ZOOM_SCALE
self.set_zoom_scale(new_scale)
# Private methods
def paintEvent(self, event):
painter = QPainter(self)
output_size = QSize()
if self.mode == Mode.PngMode:
output_size = self.zoomed_image.size()
output_rect = QRect(QPoint(), output_size)
output_rect.translate(self.rect().center() - output_rect.center())
painter.drawImage(output_rect.topLeft(), self.zoomed_image)
elif self.mode == Mode.SvgMode:
output_size = self.svgRenderer.defaultSize()
if self.zoom_scale != ZOOM_ORIGINAL_SCALE:
zoom = float(self.zoom_scale) / ZOOM_ORIGINAL_SCALE
output_size.scale(output_size.width() * zoom,
output_size.height() * zoom,
Qt.IgnoreAspectRatio)
output_rect = QRect(QPoint(), output_size)
output_rect.translate(self.rect().center() - output_rect.center())
self.svgRenderer.render(painter, output_rect)
self.setMinimumSize(output_size)
def zoom_image(self):
if self.mode == Mode.PngMode:
if self.zoom_scale == ZOOM_ORIGINAL_SCALE:
self.zoomed_image = self.image
else:
zoom = float(self.zoom_scale) / ZOOM_ORIGINAL_SCALE
self.zoomed_image = self.image.scaled(
self.image.width() * zoom,
self.image.height() * zoom, Qt.IgnoreAspectRatio,
Qt.SmoothTransformation)
def set_zoom_scale(self, new_scale):
if self.zoom_scale != new_scale:
self.zoom_scale = new_scale
self.zoom_image()
self.update()