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• Using command line find to encode files and save to same directory

  15 janvier 2017, par Ali Samii

  I am trying to execute a find bash command to process hundreds of video files that are all named video-original.mp4 but are in subdirectories of a parent directory.

  Here’s an example of the directory structure :

  videos
  
  ├── 01a
  
  │   └── video-original.mp4
  
  ├── 01b
  
  │   └── video-original.mp4
  
  ├── 02a
  
  │   └── video-original.mp4
  
  ├── 02b
  
  │   └── video-original.mp4
  
  ├── 03a
  
  │   └── video-original.mp4
  
  └── 03b
  
      └── video-original.mp4

  I am using the following command :

  find ./ -name 'video-original.mp4' -exec bash -c 'ffmpeg -i "$0" -f mp4 -vcodec libx264 -preset veryslow -profile:v high -acodec aac -movflags faststart video.mp4 -hide_banner' {} \;

  The problem I am having is that it is saving the file video.mp4 in the parent videos directory, instead of in the subdirectory next to the original video-original.mp4

  Afterwards, I want to delete the file video-original.mp4. Currently, my process entails waiting for all the videos to be reencoded, and then once complete, issuing a separate command to delete the file video-original.mp4 :

  find ./ -name 'video-original.mp4' -exec bash -c 'rm -rf "$0"' {} \;

  And my final step would be to extract a screenshot of the new video.mp4 at 10 seconds and save it as thumbnail.jpg. Again, I am currently doing that as a separate step that I execute after the previous two steps are completed.

  find ./ -name 'video.mp4' -exec bash -c 'ffmpeg -i "$0" -ss 00:00:10 -vframes 1 thumbnail.jpg' {} \;

  What I would like to do is combine these three steps into a single command so the end result will be :

  videos
  
  ├── 01a
  
  │   ├── thumbnail.jpg
  
  │   └── video.mp4
  
  ├── 01b
  
  │   ├── thumbnail.jpg
  
  │   └── video.mp4
  
  ├── 02a
  
  │   ├── thumbnail.jpg
  
  │   └── video.mp4
  
  ├── 02b
  
  │   ├── thumbnail.jpg
  
  │   └── video.mp4
  
  ├── 03a
  
  │   ├── thumbnail.jpg
  
  │   └── video.mp4
  
  └── 03b
  
      ├── thumbnail.jpg
  
      └── video.mp4

  Finally, it would be great to save that as a bash script and include it in my path in /usr/local/bin or ~/bin as an executable so I could just issue the command reencode and it would run. Would be even better if the input file could have any video file, for example, random_name.mp4 or random_name.mov or random_name.webm, basically any video file (but skipping video.mp4 at the encoding step).

• Revision dcacce6dd9 : Merge "Save pixels instead of coefficients in intra4x4 RD loop."

  27 juillet 2013, par Ronald S. Bultje

  Changed Paths :
   Modify /vp9/encoder/vp9_rdopt.c

  
  
  Merge "Save pixels instead of coefficients in intra4x4 RD loop."

• FFMPEG save last 10 sec before a movement and next 30secs

  2 novembre 2020, par Set1ish

  I have a surveillance camera that process frame by frame live video. In case of movement, I want to save a video containing the last 10 seconds before the movement and next 30 seconds after the movement.
I beleve (may be I'm wrong), that last 10 second + next 30seconds task, should be obtained without decoding-rencoding process.

  


  I try to use python with fmmpeg pipes, creating a reader and a writer, but the reader seams too slow for the stream and I loose some packets (= loose on video quality for saved file).

  


  Here my code

  


  import ffmpeg
import numpy as np

width = 1280
height = 720


process1 = (
    ffmpeg
    .input('rtsp://.....',rtsp_transport='udp', r='10', t="00:00:30")
    .output('pipe:', format='rawvideo', pix_fmt='yuv420p')
    .run_async(pipe_stdout=True)
)

process2 = (
    ffmpeg
    .input('pipe:', format='rawvideo', pix_fmt='yuv420p', s='{}x{}'.format(width, height))
    .output("prova-02-11-2020.avi", pix_fmt='yuv420p',r='10')
    .overwrite_output()
    .run_async(pipe_stdin=True)
)
while True:
    in_bytes = process1.stdout.read(width * height * 3)
    if not in_bytes:
        break
    in_frame = (
        np
        .frombuffer(in_bytes, np.uint8)
        )

    #In future I will save in_frame in a queue
    out_frame = in_frame
   
    process2.stdin.write(
        out_frame
        .astype(np.uint8)
        .tobytes()
    )

process2.stdin.close()
process1.wait()
process2.wait()


  


  If I run

  


  ffmpeg -i rtsp://... -acodec copy -vcodec copy -t "00:00:30" out.avi


  


  It look that decode-rencode process is done in quick/smart way without loosing any packet.
My dream is to make the same on python for the surveillance camera but intergrating with code that analyse the stream.

  


  I would like that the flow for creating the file, does not requires decoding + enconding. The last 10secs frames are in a queue and, at specific event, the contenet of queue plus next 30secs frames are saved into a avi file

  


  I have the constraints to have realtime motion detection on live streaming

  


  Did you have any comments or suggestion ?