Recherche avancée

Sur d’autres sites (6175)

• How to record audio with ffmpeg on ubuntu with python ?

  18 juillet 2024, par Dinh Chu

  I encountered the problem of recording output audio on Ubuntu with Python.
I want to record the output sound from the browser.
I used USB Headphone as the output device, then record sounded with FFMPEG.

  


  pactl list short sources

  


  0. alsa_output.usb-0c76_USB_PnP_Audio_Device-00.analog-stereo.monitor  module-alsa-card.c      s16le 2ch 48000Hz       SUSPENDED
1. alsa_input.usb-0c76_USB_PnP_Audio_Device-00.mono-fallback  module-alsa-card.c      s16le 1ch 48000Hz       SUSPENDED 
2. alsa_output.pci-0000_00_1f.3.iec958-stereo.monitor     module-alsa-card.c      s16le 2ch 44100Hz       SUSPENDED


  


  When I run command on Ubuntu, It recorded audio successfully.

  


  ffmpeg -f pulse -i alsa_output.usb-0c76_USB_PnP_Audio_Device-00.analog-stereo.monitor -t 10 output.wav


  


  However, when I executed the command in the project Python, the error reported :

  


  alsa_output.usb-0c76_USB_PnP_Audio_Device-00.analog-stereo.monitor: Operation not permitted


  


  or if using orther ouput :

  


  alsa_output.pci-0000_00_1f.3.iec958-stereo.monitor: Operation not permitted


  


  Details can see more attached photos :

Record error :


  


• How to record audio with ffmpeg on ubuntu 22.04 with python ?

  22 juillet 2024, par Dinh Chu

  I encountered the problem of recording output audio on Ubuntu with Python.
I want to record the output sound from the browser.
I used USB Headphone as the output device, then record sounded with FFMPEG.

  


  pactl list short sources

  


  0. alsa_output.usb-0c76_USB_PnP_Audio_Device-00.analog-stereo.monitor  module-alsa-card.c      s16le 2ch 48000Hz       SUSPENDED
1. alsa_input.usb-0c76_USB_PnP_Audio_Device-00.mono-fallback  module-alsa-card.c      s16le 1ch 48000Hz       SUSPENDED 
2. alsa_output.pci-0000_00_1f.3.iec958-stereo.monitor     module-alsa-card.c      s16le 2ch 44100Hz       SUSPENDED


  


  When I run command on Ubuntu, It recorded audio successfully.

  


  ffmpeg -f pulse -i alsa_output.usb-0c76_USB_PnP_Audio_Device-00.analog-stereo.monitor -t 10 output.wav


  


  However, when I executed the command in the project Python, the error reported :

  


  alsa_output.usb-0c76_USB_PnP_Audio_Device-00.analog-stereo.monitor: Operation not permitted


  


  or if using orther ouput :

  


  alsa_output.pci-0000_00_1f.3.iec958-stereo.monitor: Operation not permitted


  


  Details can see more attached photos :

Record error :


  


• How to write to H264 .mp4 file from Ubuntu with Python OpenCV VideoWriter, FOURCC

  12 septembre 2022, par kevinlinxc

  I am on Ubuntu 18.04, but the solution has to generalize to Debian Buster because that's what Streamlit.io Sharing websites runs on.

  


  I want to write frames with Python OpenCV to a h.264 encoded mp4 file.

  


  It has to be h.264 so that it can be shown on the web, and it has to be mp4 because it's the most common video file type.

  


  I am struggling to find a FOURCC code that works for these exact requirements. The code goes here :

  


  out = cv2.VideoWriter(output_name, cv2.VideoWriter_fourcc(*'X264'), fps, insize)

  


  I have tried avc1 and avc3, which yield Could not find encoder for codec_id=27, error: Encoder not found

  


  Note that avc1 works fine on Windows when the cisco-provided file openh264-1.8.0-win64.dll is in the same directory as the python file, but having the Linux equivalent libopenh264-1.8.0-linux64.so does not make it work on Ubuntu.

  


  H264 and X264 fail with 'H264' is not supported with codec id 27 and format 'mp4 / MP4 (MPEG-4 Part 14)'

  


  I have installed ffmpeg, x264, and libx264-dev with sudo apt-get install, but they do not change the outcome whatsover as the comment on here here says.

  


  One possible lead I have is to compile ffmpeg with 264 enabled, but I'm unfamiliar and I'm not confident I could replicate it on Streamlit, since I can't just ssh in and run commands.

  


  Is it just impossible to encode h.264 on mp4 on Linux with Python OpenCV ? This seems like it should be doable, but I've hit many dead ends.