.. 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 Out: .. code-block:: none 1.12.0 0.12.0 .. GENERATED FROM PYTHON SOURCE LINES 23-53 .. 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 nightly torch and torchaudio builds and the requisite third party libraries by adding the following code block to the top of the notebook before running it: !pip3 uninstall -y torch torchvision torchaudio !pip3 install --pre torch torchaudio --extra-index-url https://download.pytorch.org/whl/nightly/cpu !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 54-124 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 126-139 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 141-144 Audio Examples ~~~~~~~~~~~~~~ .. GENERATED FROM PYTHON SOURCE LINES 146-163 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 165-191 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 193-210 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 212-215 Video Examples ~~~~~~~~~~~~~~ .. GENERATED FROM PYTHON SOURCE LINES 217-231 Cellular automaton ^^^^^^^^^^^^^^^^^^ https://ffmpeg.org/ffmpeg-filters.html#cellauto .. code:: StreamReader(src=f"cellauto", format="lavfi") .. raw:: html .. GENERATED FROM PYTHON SOURCE LINES 233-247 Mandelbrot ^^^^^^^^^^ https://ffmpeg.org/ffmpeg-filters.html#cellauto .. code:: StreamReader(src=f"mandelbrot", format="lavfi") .. raw:: html .. GENERATED FROM PYTHON SOURCE LINES 249-263 MPlayer Test patterns ^^^^^^^^^^^^^^^^^^^^^ https://ffmpeg.org/ffmpeg-filters.html#mptestsrc .. code:: StreamReader(src=f"mptestsrc", format="lavfi") .. raw:: html .. GENERATED FROM PYTHON SOURCE LINES 265-279 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 281-295 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 297-327 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 329-333 Audio Examples ~~~~~~~~~~~~~~ .. GENERATED FROM PYTHON SOURCE LINES 333-359 .. 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 361-386 .. 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 387-390 Original ^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 390-393 .. 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 Out: .. code-block:: none filter_desc: aresample=8000,anull,aformat=sample_fmts=fltp .. raw:: html


.. GENERATED FROM PYTHON SOURCE LINES 394-397 Highpass / lowpass filter ^^^^^^^^^^^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 397-400 .. 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 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 401-404 FFT filter - Robot 🤖 ^^^^^^^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 404-407 .. 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 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 408-411 FFT filter - Whisper ^^^^^^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 411-414 .. 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 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 415-418 Video Examples ~~~~~~~~~~~~~~ .. GENERATED FROM PYTHON SOURCE LINES 418-438 .. 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 440-464 .. 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 465-467 Original ^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 467-470 .. 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 Out: .. code-block:: none filter_desc: fps=10,null,format=pix_fmts=rgb24 .. GENERATED FROM PYTHON SOURCE LINES 471-473 Mirror ^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 473-476 .. 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 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 477-479 Edge detection ^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 479-482 .. 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 Out: .. code-block:: none filter_desc: fps=10,edgedetect=mode=canny,format=pix_fmts=rgb24 .. GENERATED FROM PYTHON SOURCE LINES 483-485 Random rotation ^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 485-488 .. 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 Out: .. code-block:: none filter_desc: fps=10,rotate=angle=-random(1)*PI:fillcolor=brown,format=pix_fmts=rgb24 .. GENERATED FROM PYTHON SOURCE LINES 489-491 Pixel manipulation ^^^^^^^^^^^^^^^^^^ .. GENERATED FROM PYTHON SOURCE LINES 491-493 .. 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 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 10.591 seconds) .. _sphx_glr_download_tutorials_streaming_api2_tutorial.py: .. only :: html .. container:: sphx-glr-footer :class: 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 `_