Source code for cv2PySide6.videoutil
"""
Video utilities
===============
:mod:`cv2PySide6.videoutil` provides utility classes for running the video.
"""
from PySide6.QtCore import Qt, QPointF, Slot
from PySide6.QtGui import QMouseEvent
from PySide6.QtMultimedia import QMediaPlayer
from PySide6.QtWidgets import (
QSlider,
QStyleOptionSlider,
QWidget,
QHBoxLayout,
QStyle,
QPushButton,
)
from typing import Optional
__all__ = [
"ClickableSlider",
"MediaController",
]
[docs]
class ClickableSlider(QSlider):
"""``QSlider`` whose groove can be clicked to move to position."""
# https://stackoverflow.com/questions/52689047
def mousePressEvent(self, event: QMouseEvent):
if event.button() == Qt.LeftButton:
val = self.pixelPosToRangeValue(event.position())
self.setValue(val)
super().mousePressEvent(event)
def pixelPosToRangeValue(self, pos: QPointF) -> int:
opt = QStyleOptionSlider()
self.initStyleOption(opt)
gr = self.style().subControlRect(
QStyle.CC_Slider, opt, QStyle.SC_SliderGroove, self
)
sr = self.style().subControlRect(
QStyle.CC_Slider, opt, QStyle.SC_SliderHandle, self
)
if self.orientation() == Qt.Horizontal:
sliderLength = sr.width()
sliderMin = gr.x()
sliderMax = gr.right() - sliderLength + 1
else:
sliderLength = sr.height()
sliderMin = gr.y()
sliderMax = gr.bottom() - sliderLength + 1
pr = pos - sr.center() + sr.topLeft()
p = pr.x() if self.orientation() == Qt.Horizontal else pr.y()
return QStyle.sliderValueFromPosition(
self.minimum(),
self.maximum(),
int(p - sliderMin),
sliderMax - sliderMin,
opt.upsideDown, # type: ignore[attr-defined]
)
[docs]
class MediaController(QWidget):
"""
Widget to control :class:`QMediaPlayer`.
This controller can change the playback state and media position by
:meth:`playButton`, :meth:`stopButton`, and :meth:`slider`.
:meth:`setPlayer` sets the player to be controlled by this widget.
"""
def __init__(self, parent=None):
super().__init__(parent)
self._slider = ClickableSlider()
self._playButton = QPushButton()
self._stopButton = QPushButton()
self._player = None
self._pausedBySliderPress = False
self.playButton().clicked.connect(self.onPlayButtonClicked)
self.stopButton().clicked.connect(self.onStopButtonClicked)
self.slider().sliderPressed.connect(self.onSliderPress)
self.slider().sliderMoved.connect(self.onSliderMove)
self.slider().sliderReleased.connect(self.onSliderRelease)
layout = QHBoxLayout()
play_icon = self.style().standardIcon(QStyle.SP_MediaPlay)
self.playButton().setIcon(play_icon)
layout.addWidget(self.playButton())
stop_icon = self.style().standardIcon(QStyle.SP_MediaStop)
self.stopButton().setIcon(stop_icon)
layout.addWidget(self.stopButton())
self.slider().setOrientation(Qt.Horizontal)
layout.addWidget(self.slider())
self.setLayout(layout)
[docs]
def slider(self) -> ClickableSlider:
"""Slider to change the media position."""
return self._slider
[docs]
def playButton(self) -> QPushButton:
"""Button to play and pause the media."""
return self._playButton
[docs]
def player(self) -> Optional[QMediaPlayer]:
"""Media player which is controlled by *self*."""
return self._player
@Slot()
def onPlayButtonClicked(self):
"""Play or pause :meth:`player`."""
if self.player() is not None:
if self.player().playbackState() == QMediaPlayer.PlayingState:
self.player().pause()
else:
self.player().play()
@Slot()
def onStopButtonClicked(self):
"""Stop :meth:`player`."""
if self.player() is not None:
self.player().stop()
@Slot()
def onSliderPress(self):
"""If the media was playing, pause and move to the pressed position."""
if (
self.player() is not None
and self.player().playbackState() == QMediaPlayer.PlayingState
):
self._pausedBySliderPress = True
self.player().pause()
self.player().setPosition(self.slider().value())
@Slot(int)
def onSliderMove(self, position: int):
"""Move the media to current slider position."""
player = self.player()
if player is not None:
player.setPosition(position)
@Slot()
def onSliderRelease(self):
"""If the media was paused by slider press, play the media."""
if self.player() is not None and self._pausedBySliderPress:
self.player().play()
self._pausedBySliderPress = False
[docs]
def setPlayer(self, player: Optional[QMediaPlayer]):
"""Set :meth:`player` and connect the signals."""
old_player = self.player()
if old_player is not None:
self.disconnectPlayer(old_player)
self._player = player
if player is not None:
self.connectPlayer(player)
[docs]
def connectPlayer(self, player: QMediaPlayer):
"""Connect signals and slots with *player*."""
player.durationChanged.connect( # type: ignore[attr-defined]
self.onMediaDurationChange
)
player.positionChanged.connect( # type: ignore[attr-defined]
self.onMediaPositionChange
)
player.playbackStateChanged.connect( # type: ignore[attr-defined]
self.onPlaybackStateChange
)
[docs]
def disconnectPlayer(self, player: QMediaPlayer):
"""Disconnect signals and slots with *player*."""
player.durationChanged.disconnect( # type: ignore[attr-defined]
self.onMediaDurationChange
)
player.positionChanged.disconnect( # type: ignore[attr-defined]
self.onMediaPositionChange
)
player.playbackStateChanged.disconnect( # type: ignore[attr-defined]
self.onPlaybackStateChange
)
@Slot(int)
def onMediaDurationChange(self, duration: int):
"""Set the slider range to media duration."""
self.slider().setRange(0, duration)
@Slot(int)
def onMediaPositionChange(self, position: int):
"""Update the slider position to video position."""
self.slider().setValue(position)
@Slot(QMediaPlayer.PlaybackState)
def onPlaybackStateChange(self, state: QMediaPlayer.PlaybackState):
"""Switch the play icon and pause icon by *state*."""
if state == QMediaPlayer.PlayingState:
pause_icon = self.style().standardIcon(QStyle.SP_MediaPause)
self.playButton().setIcon(pause_icon)
else:
play_icon = self.style().standardIcon(QStyle.SP_MediaPlay)
self.playButton().setIcon(play_icon)