path: root/voctocore/lib/video/mix.py

#!/usr/bin/python3
import logging
from gi.repository import Gst
from enum import Enum

from lib.config import Config

class ComposteModes(Enum):
    fullscreen = 0

class VideoMix(object):
    log = logging.getLogger('VideoMix')

    mixingPipeline = None

    caps = None
    names = []

    compositeMode = ComposteModes.fullscreen
    sourceA = 0
    sourceB = 1

    def __init__(self):
        self.caps = Config.get('mix', 'videocaps')

        self.names = Config.getlist('sources', 'video')
        self.log.info('Configuring Mixer for %u Sources', len(self.names))

        pipeline = """
            videomixer name=mix !
            {caps} !
            textoverlay text=mixer halignment=left valignment=top ypad=175 !
            intervideosink channel=video_mix
        """.format(
            caps=self.caps
        )

        for idx, name in enumerate(self.names):
            pipeline += """
                intervideosrc channel=video_{name}_mixer !
                {caps} !
                videoscale !
                capsfilter name=caps_{idx} !
                mix.
            """.format(
                name=name,
                caps=self.caps,
                idx=idx
            )

        self.log.debug('Creating Mixing-Pipeline:\n%s', pipeline)
        self.mixingPipeline = Gst.parse_launch(pipeline)

        self.log.debug('Initializing Mixer-State')
        self.updateMixerState()

        self.log.debug('Launching Mixing-Pipeline:\n%s', pipeline)
        self.mixingPipeline.set_state(Gst.State.PLAYING)

    def updateMixerState(self):
        if self.compositeMode == ComposteModes.fullscreen:
            self.updateMixerStateFullscreen()

    def updateMixerStateFullscreen(self):
        self.log.info('Updating Mixer-State for Fullscreen-Composition')
        for idx, name in enumerate(self.names):
            alpha = int(idx == self.sourceA)

            self.log.debug('Setting Mixerpad %u to x/y=0 and alpha=%u', idx, alpha)
            mixerpad = self.mixingPipeline.get_by_name('mix').get_static_pad('sink_%u' % idx)
            mixerpad.set_property('alpha', alpha )
            mixerpad.set_property('xpos', 0)
            mixerpad.set_property('ypos', 0)

            self.log.debug('Resetting Scaler %u to non-scaling', idx)
            capsfilter = self.mixingPipeline.get_by_name('caps_%u' % idx)
            capsfilter.set_property('caps', Gst.Caps.from_string(self.caps))

    def setVideoA(self, source):
        self.sourceA = source
        self.updateMixerState()

    def setVideoB(self, source):
        self.sourceN = source
        self.updateMixerState()