.. DO NOT EDIT. .. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY. .. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE: .. "tutorials/streaming_api2_tutorial.py" .. LINE NUMBERS ARE GIVEN BELOW. .. only:: html .. note:: :class: sphx-glr-download-link-note Click :ref:`here ` to download the full example code .. rst-class:: sphx-glr-example-title .. _sphx_glr_tutorials_streaming_api2_tutorial.py: Media Stream API - Pt. 2 ======================== This tutorial is the continuation of `Media Stream API - Pt.1 <./streaming_api_tutorial.html>`__. This shows how to use `StreamReader` for - Device inputs, such as microphone, webcam and screen recording - Generating synthetic audio / video - Applying preprocessing with custom filter expressions .. GENERATED FROM PYTHON SOURCE LINES 14-21 .. code-block:: default import torch import torchaudio print(torch.__version__) print(torchaudio.__version__) .. rst-class:: sphx-glr-script-out .. code-block:: none 1.12.1 0.12.1 .. GENERATED FROM PYTHON SOURCE LINES 23-50 .. code-block:: default try: from torchaudio.io import StreamReader except ModuleNotFoundError: try: import google.colab print( """ To enable running this notebook in Google Colab, install the requisite third party libraries by running the following code: !add-apt-repository -y ppa:savoury1/ffmpeg4 !apt-get -qq install -y ffmpeg """ ) except ModuleNotFoundError: pass raise import IPython import matplotlib.pyplot as plt base_url = "https://download.pytorch.org/torchaudio/tutorial-assets" AUDIO_URL = f"{base_url}/Lab41-SRI-VOiCES-src-sp0307-ch127535-sg0042.wav" VIDEO_URL = f"{base_url}/stream-api/NASAs_Most_Scientifically_Complex_Space_Observatory_Requires_Precision-MP4.mp4" .. GENERATED FROM PYTHON SOURCE LINES 51-121 Audio / Video device input -------------------------- .. seealso:: - `Accelerated Video Decoding with NVDEC <../hw_acceleration_tutorial.html>`__. - `Online ASR with Emformer RNN-T <./online_asr_tutorial.html>`__. - `Device ASR with Emformer RNN-T <./device_asr.html>`__. Given that the system has proper media devices and libavdevice is configured to use the devices, the streaming API can pull media streams from these devices. To do this, we pass additional parameters ``format`` and ``option`` to the constructor. ``format`` specifies the device component and ``option`` dictionary is specific to the specified component. The exact arguments to be passed depend on the system configuration. Please refer to https://ffmpeg.org/ffmpeg-devices.html for the detail. The following example illustrates how one can do this on MacBook Pro. First, we need to check the available devices. .. code:: $ ffmpeg -f avfoundation -list_devices true -i "" [AVFoundation indev @ 0x143f04e50] AVFoundation video devices: [AVFoundation indev @ 0x143f04e50] [0] FaceTime HD Camera [AVFoundation indev @ 0x143f04e50] [1] Capture screen 0 [AVFoundation indev @ 0x143f04e50] AVFoundation audio devices: [AVFoundation indev @ 0x143f04e50] [0] MacBook Pro Microphone We use `FaceTime HD Camera` as video device (index 0) and `MacBook Pro Microphone` as audio device (index 0). If we do not pass any ``option``, the device uses its default configuration. The decoder might not support the configuration. .. code:: >>> StreamReader( ... src="0:0", # The first 0 means `FaceTime HD Camera`, and ... # the second 0 indicates `MacBook Pro Microphone`. ... format="avfoundation", ... ) [avfoundation @ 0x125d4fe00] Selected framerate (29.970030) is not supported by the device. [avfoundation @ 0x125d4fe00] Supported modes: [avfoundation @ 0x125d4fe00] 1280x720@[1.000000 30.000000]fps [avfoundation @ 0x125d4fe00] 640x480@[1.000000 30.000000]fps Traceback (most recent call last): File "", line 1, in ... RuntimeError: Failed to open the input: 0:0 By providing ``option``, we can change the format that the device streams to a format supported by decoder. .. code:: >>> streamer = StreamReader( ... src="0:0", ... format="avfoundation", ... option={"framerate": "30", "pixel_format": "bgr0"}, ... ) >>> for i in range(streamer.num_src_streams): ... print(streamer.get_src_stream_info(i)) SourceVideoStream(media_type='video', codec='rawvideo', codec_long_name='raw video', format='bgr0', bit_rate=0, width=640, height=480, frame_rate=30.0) SourceAudioStream(media_type='audio', codec='pcm_f32le', codec_long_name='PCM 32-bit floating point little-endian', format='flt', bit_rate=3072000, sample_rate=48000.0, num_channels=2) .. GENERATED FROM PYTHON SOURCE LINES 123-136 Synthetic source streams ------------------------ As a part of device integration, ffmpeg provides a "virtual device" interface. This interface provides synthetic audio / video data generation using libavfilter. To use this, we set ``format=lavfi`` and provide a filter description to ``src``. The detail of filter description can be found at https://ffmpeg.org/ffmpeg-filters.html .. GENERATED FROM PYTHON SOURCE LINES 138-141 Audio Examples ~~~~~~~~~~~~~~ .. GENERATED FROM PYTHON SOURCE LINES 143-160 Sine wave ^^^^^^^^^ https://ffmpeg.org/ffmpeg-filters.html#sine .. code:: StreamReader(src="sine=sample_rate=8000:frequency=360", format="lavfi") .. raw:: html .. GENERATED FROM PYTHON SOURCE LINES 162-188 Signal with arbitral expression ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ https://ffmpeg.org/ffmpeg-filters.html#aevalsrc .. code:: # 5 Hz binaural beats on a 360 Hz carrier StreamReader( src=( 'aevalsrc=' 'sample_rate=8000:' 'exprs=0.1*sin(2*PI*(360-5/2)*t)|0.1*sin(2*PI*(360+5/2)*t)' ), format='lavfi', ) .. raw:: html .. GENERATED FROM PYTHON SOURCE LINES 190-207 Noise ^^^^^ https://ffmpeg.org/ffmpeg-filters.html#anoisesrc .. code:: StreamReader(src="anoisesrc=color=pink:sample_rate=8000:amplitude=0.5", format="lavfi") .. raw:: html .. GENERATED FROM PYTHON SOURCE LINES 209-212 Video Examples ~~~~~~~~~~~~~~ .. GENERATED FROM PYTHON SOURCE LINES 214-228 Cellular automaton ^^^^^^^^^^^^^^^^^^ https://ffmpeg.org/ffmpeg-filters.html#cellauto .. code:: StreamReader(src=f"cellauto", format="lavfi") .. raw:: html .. GENERATED FROM PYTHON SOURCE LINES 230-244 Mandelbrot ^^^^^^^^^^ https://ffmpeg.org/ffmpeg-filters.html#cellauto .. code:: StreamReader(src=f"mandelbrot", format="lavfi") .. raw:: html .. GENERATED FROM PYTHON SOURCE LINES 246-260 MPlayer Test patterns ^^^^^^^^^^^^^^^^^^^^^ https://ffmpeg.org/ffmpeg-filters.html#mptestsrc .. code:: StreamReader(src=f"mptestsrc", format="lavfi") .. raw:: html .. GENERATED FROM PYTHON SOURCE LINES 262-276 John Conway's life game ^^^^^^^^^^^^^^^^^^^^^^^ https://ffmpeg.org/ffmpeg-filters.html#life .. code:: StreamReader(src=f"life", format="lavfi") .. raw:: html .. GENERATED FROM PYTHON SOURCE LINES 278-292 Sierpinski carpet/triangle fractal ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ https://ffmpeg.org/ffmpeg-filters.html#sierpinski .. code:: StreamReader(src=f"sierpinski", format="lavfi") .. raw:: html .. GENERATED FROM PYTHON SOURCE LINES 294-324 Custom filters -------------- When defining an output stream, you can use :py:meth:`~torchaudio.io.StreamReader.add_audio_stream` and :py:meth:`~torchaudio.io.StreamReader.add_video_stream` methods. These methods take ``filter_desc`` argument, which is a string formatted according to ffmpeg's `filter expression `_. The difference between ``add_basic_(audio|video)_stream`` and ``add_(audio|video)_stream`` is that ``add_basic_(audio|video)_stream`` constructs the filter expression and passes it to the same underlying implementation. Everything ``add_basic_(audio|video)_stream`` can be achieved with ``add_(audio|video)_stream``. .. note:: - When applying custom filters, the client code must convert the audio/video stream to one of the formats that torchaudio can convert to tensor format. This can be achieved, for example, by applying ``format=pix_fmts=rgb24`` to video stream and ``aformat=sample_fmts=fltp`` to audio stream. - Each output stream has separate filter graph. Therefore, it is not possible to use different input/output streams for a filter expression. However, it is possible to split one input stream into multiple of them, and merge them later. .. GENERATED FROM PYTHON SOURCE LINES 326-330 Audio Examples ~~~~~~~~~~~~~~ .. GENERATED FROM PYTHON SOURCE LINES 330-356 .. code-block:: default # fmt: off descs = [ # No filtering "anull", # Apply a highpass filter then a lowpass filter "highpass=f=200,lowpass=f=1000", # Manipulate spectrogram ( "afftfilt=" "real='hypot(re,im)*sin(0)':" "imag='hypot(re,im)*cos(0)':" "win_size=512:" "overlap=0.75" ), # Manipulate spectrogram ( "afftfilt=" "real='hypot(re,im)*cos((random(0)*2-1)*2*3.14)':" "imag='hypot(re,im)*sin((random(1)*2-1)*2*3.14)':" "win_size=128:" "overlap=0.8" ), ] # fmt: on .. GENERATED FROM PYTHON SOURCE LINES 358-383 .. code-block:: default sample_rate = 8000 streamer = StreamReader(AUDIO_URL) for desc in descs: streamer.add_audio_stream( frames_per_chunk=40000, filter_desc=f"aresample={sample_rate},{desc},aformat=sample_fmts=fltp", ) chunks = next(streamer.stream()) def _display(i): print("filter_desc:", streamer.get_out_stream_info(i).filter_description) _, axs = plt.subplots(2, 1) waveform = chunks[i][:, 0] axs[0].plot(waveform) axs[0].grid(True) axs[0].set_ylim([-1, 1]) plt.setp(axs[0].get_xticklabels(), visible=False) axs[1].specgram(waveform, Fs=sample_rate) return IPython.display.Audio(chunks[i].T, rate=sample_rate) .. GENERATED FROM PYTHON SOURCE LINES 384-387 Original ^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 387-390 .. code-block:: default _display(0) .. image-sg:: /tutorials/images/sphx_glr_streaming_api2_tutorial_001.png :alt: streaming api2 tutorial :srcset: /tutorials/images/sphx_glr_streaming_api2_tutorial_001.png :class: sphx-glr-single-img .. rst-class:: sphx-glr-script-out .. code-block:: none filter_desc: aresample=8000,anull,aformat=sample_fmts=fltp .. raw:: html


.. GENERATED FROM PYTHON SOURCE LINES 391-394 Highpass / lowpass filter ^^^^^^^^^^^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 394-397 .. code-block:: default _display(1) .. image-sg:: /tutorials/images/sphx_glr_streaming_api2_tutorial_002.png :alt: streaming api2 tutorial :srcset: /tutorials/images/sphx_glr_streaming_api2_tutorial_002.png :class: sphx-glr-single-img .. rst-class:: sphx-glr-script-out .. code-block:: none filter_desc: aresample=8000,highpass=f=200,lowpass=f=1000,aformat=sample_fmts=fltp .. raw:: html


.. GENERATED FROM PYTHON SOURCE LINES 398-401 FFT filter - Robot 🤖 ^^^^^^^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 401-404 .. code-block:: default _display(2) .. image-sg:: /tutorials/images/sphx_glr_streaming_api2_tutorial_003.png :alt: streaming api2 tutorial :srcset: /tutorials/images/sphx_glr_streaming_api2_tutorial_003.png :class: sphx-glr-single-img .. rst-class:: sphx-glr-script-out .. code-block:: none filter_desc: aresample=8000,afftfilt=real='hypot(re,im)*sin(0)':imag='hypot(re,im)*cos(0)':win_size=512:overlap=0.75,aformat=sample_fmts=fltp .. raw:: html


.. GENERATED FROM PYTHON SOURCE LINES 405-408 FFT filter - Whisper ^^^^^^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 408-411 .. code-block:: default _display(3) .. image-sg:: /tutorials/images/sphx_glr_streaming_api2_tutorial_004.png :alt: streaming api2 tutorial :srcset: /tutorials/images/sphx_glr_streaming_api2_tutorial_004.png :class: sphx-glr-single-img .. rst-class:: sphx-glr-script-out .. code-block:: none filter_desc: aresample=8000,afftfilt=real='hypot(re,im)*cos((random(0)*2-1)*2*3.14)':imag='hypot(re,im)*sin((random(1)*2-1)*2*3.14)':win_size=128:overlap=0.8,aformat=sample_fmts=fltp .. raw:: html


.. GENERATED FROM PYTHON SOURCE LINES 412-415 Video Examples ~~~~~~~~~~~~~~ .. GENERATED FROM PYTHON SOURCE LINES 415-435 .. code-block:: default # fmt: off descs = [ # No effect "null", # Split the input stream and apply horizontal flip to the right half. ( "split [main][tmp];" "[tmp] crop=iw/2:ih:0:0, hflip [flip];" "[main][flip] overlay=W/2:0" ), # Edge detection "edgedetect=mode=canny", # Rotate image by randomly and fill the background with brown "rotate=angle=-random(1)*PI:fillcolor=brown", # Manipulate pixel values based on the coordinate "geq=r='X/W*r(X,Y)':g='(1-X/W)*g(X,Y)':b='(H-Y)/H*b(X,Y)'" ] # fmt: on .. GENERATED FROM PYTHON SOURCE LINES 437-461 .. code-block:: default streamer = StreamReader(VIDEO_URL) for desc in descs: streamer.add_video_stream( frames_per_chunk=30, filter_desc=f"fps=10,{desc},format=pix_fmts=rgb24", ) streamer.seek(12) chunks = next(streamer.stream()) def _display(i): print("filter_desc:", streamer.get_out_stream_info(i).filter_description) _, axs = plt.subplots(1, 3, figsize=(8, 1.9)) chunk = chunks[i] for j in range(3): axs[j].imshow(chunk[10 * j + 1].permute(1, 2, 0)) axs[j].set_axis_off() plt.tight_layout() plt.show(block=False) .. GENERATED FROM PYTHON SOURCE LINES 462-464 Original ^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 464-467 .. code-block:: default _display(0) .. image-sg:: /tutorials/images/sphx_glr_streaming_api2_tutorial_005.png :alt: streaming api2 tutorial :srcset: /tutorials/images/sphx_glr_streaming_api2_tutorial_005.png :class: sphx-glr-single-img .. rst-class:: sphx-glr-script-out .. code-block:: none filter_desc: fps=10,null,format=pix_fmts=rgb24 .. GENERATED FROM PYTHON SOURCE LINES 468-470 Mirror ^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 470-473 .. code-block:: default _display(1) .. image-sg:: /tutorials/images/sphx_glr_streaming_api2_tutorial_006.png :alt: streaming api2 tutorial :srcset: /tutorials/images/sphx_glr_streaming_api2_tutorial_006.png :class: sphx-glr-single-img .. rst-class:: sphx-glr-script-out .. code-block:: none filter_desc: fps=10,split [main][tmp];[tmp] crop=iw/2:ih:0:0, hflip [flip];[main][flip] overlay=W/2:0,format=pix_fmts=rgb24 .. GENERATED FROM PYTHON SOURCE LINES 474-476 Edge detection ^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 476-479 .. code-block:: default _display(2) .. image-sg:: /tutorials/images/sphx_glr_streaming_api2_tutorial_007.png :alt: streaming api2 tutorial :srcset: /tutorials/images/sphx_glr_streaming_api2_tutorial_007.png :class: sphx-glr-single-img .. rst-class:: sphx-glr-script-out .. code-block:: none filter_desc: fps=10,edgedetect=mode=canny,format=pix_fmts=rgb24 .. GENERATED FROM PYTHON SOURCE LINES 480-482 Random rotation ^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 482-485 .. code-block:: default _display(3) .. image-sg:: /tutorials/images/sphx_glr_streaming_api2_tutorial_008.png :alt: streaming api2 tutorial :srcset: /tutorials/images/sphx_glr_streaming_api2_tutorial_008.png :class: sphx-glr-single-img .. rst-class:: sphx-glr-script-out .. code-block:: none filter_desc: fps=10,rotate=angle=-random(1)*PI:fillcolor=brown,format=pix_fmts=rgb24 .. GENERATED FROM PYTHON SOURCE LINES 486-488 Pixel manipulation ^^^^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 488-490 .. code-block:: default _display(4) .. image-sg:: /tutorials/images/sphx_glr_streaming_api2_tutorial_009.png :alt: streaming api2 tutorial :srcset: /tutorials/images/sphx_glr_streaming_api2_tutorial_009.png :class: sphx-glr-single-img .. rst-class:: sphx-glr-script-out .. code-block:: none filter_desc: fps=10,geq=r='X/W*r(X,Y)':g='(1-X/W)*g(X,Y)':b='(H-Y)/H*b(X,Y)',format=pix_fmts=rgb24 .. rst-class:: sphx-glr-timing **Total running time of the script:** ( 0 minutes 13.604 seconds) .. _sphx_glr_download_tutorials_streaming_api2_tutorial.py: .. only:: html .. container:: sphx-glr-footer sphx-glr-footer-example .. container:: sphx-glr-download sphx-glr-download-python :download:`Download Python source code: streaming_api2_tutorial.py ` .. container:: sphx-glr-download sphx-glr-download-jupyter :download:`Download Jupyter notebook: streaming_api2_tutorial.ipynb ` .. only:: html .. rst-class:: sphx-glr-signature `Gallery generated by Sphinx-Gallery `_