mixtape: awesome mix vol. 1 🎵📼

|[●▪▪●]| A python based gstreamer player-mini-framework.

This project is in pre-alpha and most functionality is incomplete and the API is most likely to change

Gstreamer is a pipeline based framework for building complex multimedia processing systems. It is written in C, based on GObject, and offers several bindings in other languages, including python.

If you are unfamiliar with Gstreamer, you should start with the GStreamer tutorials.

mixtape offers a few utility classes and functions for a gstreamer application, and auto generates service interfaces for your application.

Project goal

Python is a great language for prototyping and integration tests. The goal of the project is to have something in between gst-launch and writing a full python application for testing and prototyping.

Features:

• Pluggable declarative definitions of Player features.
• Optional loops (glib, asyncio, ...) (WIP)
• Auto-generated cmdline, console, http and dbus service interfaces* (WIP)
• cmdline, console, http and dbus service cmdline commands to jump start services from pipeline descriptions (WIP)

Quickstart

Install

You can use pip to install mixtape:

pip install mixtape

Usage

You can use mixtape similar to how you use gst-launch-1.0 by passing a pipeline description to the from_desc constructor:

from mixtape import AsyncPlayer as Player


desc = "videotestsrc num-buffers=100 ! fakesink"

async def main(self):
    p = Player.from_desc(desc)
    await p.play()
    asyncio.sleep(5)
    await p.stop()


asyncio.run(main())

The run classmethod is a shortcut for setting up the asyncio boilerplate and running a pipeline until an eos event or error:

from mixtape import AsyncPlayer as Player

desc = "videotestsrc num-buffers=100 ! fakesink"
p = Player.from_desc(desc)  # creates a player from a pipeline description
p.run(autoplay=True)  # init of pipeline (i.e. bus) and sets the pipeline to playing state (default)

You can run a loop and the player in a background thread:

from mixtape import AsyncPlayer as Player
import threading

desc = "videotestsrc ! fakesink"

p = player.from_description(desc)
t = threading.Thread(target=lambda: p.run(autoplay=False)) # init the player in another thread
t.daemon = True  # set the thread to background
t.start()
seq = ['play', 'pause', 'play', 'stop']
for step in seq:
    sleep(3)
    s = getattr(p, "call_%s" % step) # call_x schedules the coroutine
    s()  # set the pipeline to `play`, `pause`, `play` and `stop`
t.join()

Constructing a dynamic pipeline and passing it to the player:

import Gst

pipe = Gst.Pipeline.new('dynamic')
src = Gst.ElementFactory.make('videotestsrc')
sink = Gst.ElementFactory.make('fakesink')
pipe.add(src, sink)
src.link(sink)

p = Player(pipeline=pipe)

(WIP) This example uses a feature class that uses the centricular webrtc example:

from mixtape import AsyncPlayer as Player
from mixtape.features import WebRTC

desc = "videotestsrc ! tee name=tee ! queue ! fakesink"
p = Player.from_desc(desc, features=[WebRTC])
p.run()
p.webrtc.set_peer(1231)
p.webrtc.attach(tee)

This example uses a feature class that uses the ridgerun gst-shark profiler:

from mixtape import AsyncPlayer as Player
from mixtape.features import GstShark

desc = "videotestsrc num-buffers=100 ! tee name=tee ! queue ! fakesink"
p = Player.from_desc(desc, features=[GstShark])
p.gstshark.set_tracers('latency')
p.run()

Player base interface (Draft)

(WIP)

- Player.from_desc

- player.run

- player.play

- player.stop

- player.pause

Feature interface (Draft)

(WIP)

from mixtape.features import AwesomeFeature, Attachable


class WebRTC(AwesomeFeature, Attachable):

    name = 'webrtc'
    plugins_dependencies = ['webrtcbin', 'nice']
    bin_desc = ""

def check(self, pipeline):
    pass

def attach(self, pipeline, element, pad):
    pass

def detach(self, pipeline, element, pad):
    pass

def check(self, pipeline):
    pass

def init(self, pipeline)
    pass

def exit(self, pipeline)
    pass

....___.___.___.___.___.__....
|:                          :|
|:    Awesome mix vol 1     :|
|:     ,-.   _____   ,-.    :|
|:    ( `)) [_____] ( `))   :|
|:     `-`   ' ' '   `-`    :|
|:     ,______________.     :|
|...../::::o::::::o::::\.....|
|..../:::O::::::::::O:::\....|
|---/----.----.----.-----`---|

We are Groot.