gstreasy

A re-imagining of gstreamer-python.

Some of the new features:

• Auto setup/teardown of main loop thread
• Auto detect caps if in gst-launch command
• Auto detect and configure appsink and appsrc if in command
• Support for appsink and appsrc in same pipeline
• Support for multiple sinks in the same pipeline
• Faster Gst.Sample -> np.ndarray by caching caps

Example Usage

Install with: python -m pip install gstreasy

Also check out the user_code.py script for an appsrc example. As I write more examples they will appear in the examples/ folder.

Simple pipeline without an appsink element:

simple_cmd = "videotestsrc num-buffers=60 ! autovideosink"
with GstPipeline(simple_cmd) as pipeline:
    print("Running simple pipeline")

Pipeline with an appsink element:

appsink_cmd = "videotestsrc num-buffers=60 ! appsink emit-signals=true sync=false"
with GstPipeline(appsink_cmd) as pipeline:
    while pipeline:
        buffer = pipeline.pop()
        if buffer:
            type(buffer.data)  # np.ndarray

Pipeline using tee element and multiple sinks:

tee_cmd = '''
    videotestsrc num-buffers=60 ! tee name=t
    t. ! queue ! video/x-raw,format=RGB,framerate=60/1
       ! appsink emit-signals=true sync=false
    t. ! queue ! video/x-raw,format=RGB,framerate=60/1
       ! jpegenc ! avimux
       ! filesink location=recording.mp4
'''
with GstPipeline(tee_cmd) as pipeline:
    while pipeline:
        buffer = pipeline.pop()
        # do whatever you want with the buffer's ndarray
    # Meanwhile recording.mp4 is being written

Develop

All dev tasks can be handled with the run.sh script but it just wraps standard tools if you can't/don't want use it.

• python -m pip install -e .[dev,doc] to install deps
• tox to run tests for py3.7, py3.10, and py3.11.
• flake8 and mypy for linting
• pdoc -d google src/gstreasy for online docs

To help debugging, you can breakpoint inside functions that run on a separate thread, if you insert the following lines just before your breakpoint. Tested on PyCharm but should work with most IDEs. Please remove them before opening your pull request.

import pydevd
pydevd.settrace(suspend=False, trace_only_current_thread=True)