voctocore/lib/video/mix.py



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

from lib.config import Config

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

    mixingPipeline = None

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

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

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

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

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

        mixerpad = self.mixingPipeline.get_by_name('mix').get_static_pad('sink_0')
        mixerpad.set_property('alpha', 0.5)
        mixerpad.set_property('xpos', 64)
        mixerpad.set_property('ypos', 64)

        mixerpad = self.mixingPipeline.get_by_name('mix').get_static_pad('sink_1')
        mixerpad.set_property('alpha', 0.2)

        capsilter = self.mixingPipeline.get_by_name('caps_1')
        capsilter.set_property('caps', Gst.Caps.from_string(
            'video/x-raw,width=320,height=180'))