modules.vision.streaming.rtsp_stream

Classes Diagram

Module Dependencies

Classes

RtspSource

Inherits from: VideoSource, VideoRecorder

RTSP source + recorder using GStreamer.

This class builds a GStreamer pipeline that reads an RTSP H264 stream, decodes
frames for use in the application (via an appsink) and optionally records the
incoming H264 stream to disk (via separate pipelines). It implements the
VideoSource interface (frame retrieval) and VideoRecorder (start/stop
recording).

Notes: \

• Frame format exposed by get_frame() is a BGR numpy array compatible
  with OpenCV.
  - Recording is reference-counted: multiple callers can call
  start_recording() and must balance with stop_recording().

Constructor

RtspSource(self, rtsp_url: str, camera_name: str)

Members

_camera_name

_record_requests: int

_app_pipeline: Gst.Pipeline | None

_rec_pipeline: Gst.Pipeline | None

_app_sink: GstApp.AppSink | None

_plays: bool

_last_frame

_fps: float

_current_recording_file

_rtsp_url

Methods

_create_pipeline(self, pipeline_str: str) → None

Create the GST pipeline according to the provided description.

Args:
pipeline_str: the pipeline description.

Returns:

_connect(self) → None

_create_recording_pipeline(rtsp_url: str, output_file: str) → Gst.Pipeline

@staticmethod

Create a fresh recording pipeline for each recording session.

_handle_new_sample(self, sink: GstApp.AppSink) → Gst.FlowReturn

GStreamer appsink callback to handle a new decoded sample.

The BGR sample is stored in self._last_frame for retrieval by the
consumer via get_frame().

Args:
sink: The GstApp.AppSink that emitted the "new-sample" signal.

Returns:
A Gst.FlowReturn value. Returns Gst.FlowReturn.OK on success so the
pipeline continues, and Gst.FlowReturn.ERROR on unrecoverable
failures.

start(self) → None

@override

Start playing the RTSP pipeline.

Transitions the internal GStreamer pipeline into PLAYING state so that
frames start being decoded and delivered.

Raises:
RuntimeError: If GStreamer fails to change to the PLAYING state.

stop(self) → None

@override

Stop the RTSP pipeline and release resources.

Transitions the pipeline to NULL state. Consumers should call this
when the source is no longer needed to easy the CPU & memory usage of GST.
Calling this function will also stop the pending recording if one is being done.

Raises:
RuntimeError: If GStreamer fails to change to the NULL state.

start_recording(self, saving_path: str) → None

@override

Begin recording the incoming stream to disk.

This method is reference-counted: the first caller will create a new
recording fragment and open the recorder. Callers must match with
stop_recording() to actually stop the recording.

_stop_recording_pipeline(self) → None

Stop a previously requested recording.

Decrements the internal record-request counter. When the counter reaches
zero the recorder valve is closed so that recording stops. The method
does nothing if recording was not active, but callers should ensure
balanced start/stop calls.

stop_recording(self) → None

@override

Stop recording and finalize the file.

get_fps(self) → float

@override

Return the frames-per-second of the incoming stream.

get_frame(self) → tuple[bool, any]

@override

Retrieve the most recent frame.

is_opened(self) → bool

@override

Check if the stream is active.