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• How to encode mp4 so that Apple devices can stream VP9 encoded Videos via fmp4 HLS ? [closed]

  13 mai, par Leon S

  The question is in the title...

  I have not figured it out, obviously Youtube has achieved that, but how could i do it in my own app so that i can effectively stream vp9 encoded content in my app.

  Would be great to get a solution, maybe some ffmpeg settings or something like that? I know that it is officially not supported, but everywhere i look they say that it is still possible, and even "quite easy", e.g. here: https://www.streamingmedia.com/Articles/ReadArticle.aspx?ArticleID=133907

  Trief multiple fmp4 encodings so far for vp9 but neither my app player nor safari play the videos, even though VLC and co do.

• piping data into an ffmpeg subprocess. Why does write() get stuck ? [closed]

  12 mai, par Tebyy

  It displays the number of frames at the beginning and shows that there are over 300, but when I count all the frames in the loop, the last one I see is 53, and then it only displays the value of 'ret', which is always true. I'm wondering what could be causing this issue of not reading all the frames, resulting in the file not being closed after reading. From what I've read, 'ret' should return false when there are no more frames to read, but because it's not reading all the frames, this isn't happening. Does anyone have any idea what could be causing this?

  Edit: I solved the problem by adding a Thread. Thanks everyone for the help!

  I changed those lines of code:

  recogniteAndPushFramesToFfmpeg("video-979257305707693982.mp4", ffmpeg_process)
  # In function "recogniteAndPushFramesToFfmpeg"
  process.stdin.write(frame)
  

  to these:

  ffmpeg_thread = Thread(target=recogniteAndPushFramesToFfmpeg, args=("video-979257305707693982.mp4", ffmpeg_process))
  ffmpeg_thread.start()
  # In function "recogniteAndPushFramesToFfmpeg"
  process.stdin.write(frame.tobytes())
  

  Code:

  import subprocess
  import cv2
  
  def recogniteAndPushFramesToFfmpeg(video_path, process):
      cap = cv2.VideoCapture(video_path)
      i = 1
      print('Frames:', cap.get(cv2.CAP_PROP_FRAME_COUNT))
      while cap.isOpened():
          ret, frame = cap.read()
          print(ret)
          if not ret:
              break
  
          process.stdin.write(frame)
          process.stdin.flush()
          print('Frame:', i)
          i += 1
  
      cap.release()
      process.stdin.close()
      #process.wait()
      return
      
  
  ffmpeg_command = [
      'ffmpeg', '-f', 'rawvideo', '-s:v', '1920x1080', '-r', '60',
      '-i', '-', '-vf', 'setpts=2.5*PTS',
      '-c:v', 'libvpx-vp9', '-g', '60',
      '-f', 'webm', '-'
  ]
  ffmpeg_process = subprocess.Popen(ffmpeg_command, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, bufsize=-1)
  recogniteAndPushFramesToFfmpeg("video-979257305707693982.mp4", ffmpeg_process)
  

  Python Logs:

  Frames: 328.0
  ...
  True
  Frame 50
  True
  Frame 51
  True
  Frame 52
  True
  Frame 53
  True
  

  I placed cap.isOpened() in the loop to check if it always returns true, and when I printed it, it always showed true

  Link to video: Tested Video

• Adding Dynamic Progress Bar to FFMpeg Video Output (Mac) [closed]

  12 mai, par saurav tripathi

  I'm trying to add a dynamic progress bar to the bottom of a video using ffmpeg on my Mac. Here's the command I'm currently using:

  ffmpeg -i "/Volumes/hard-drive/Auto-pilot-video/upload-ready-video/one-two-ka-four.mp4" -filter_complex \
  "[0:v]drawbox=y=ih-20:color=yellow@0.5:width=iw*(t/606.15):height=20:t=fill[v]" \
  -map "[v]" -map 0:a -c:a copy -preset fast output.mp4
  

  Question:

  

  As you can see in the image right now, it just a fixed yellow bar at the bottom of the screen. But instead of just fixed at bottom I want a dynamically moving bar at the bottom.

  Is it possible to create a dynamic progress bar using ffmpeg filters on macOS? If so, could you please suggest the appropriate filter(s) and their configuration for achieving this effect?

• I am unable to decode the frames in python using ffmpeg [closed]

  12 mai, par Saail Chavan

  import pylwdrone
  import cv2
  import numpy as np
  
  # Initialize the LWDrone object
  drone = pylwdrone.LWDrone()
  
  # Start the video stream
  for packet in drone.start_video_stream():
      try:
          # Print the size of the frame data
          print("Packet frame bytes size:", len(packet.frame_bytes))
  
          # Print a portion of the frame data (first 100 bytes)
          print("First 100 bytes of frame data:", packet.frame_bytes[:100])
  
          # Convert the frame data to numpy array
          frame = np.frombuffer(packet.frame_bytes, dtype=np.uint8)
  
          # Get the actual frame shape
          frame_shape = frame.shape
          print("Actual frame shape:", frame_shape)
  
          # Reshape the frame data
          frame = frame.reshape((frame_shape[0]//3, 3))
  
          # Display the frame
          cv2.imshow("Debug Frame", frame)
  
          # Check for 'q' key to exit
          if cv2.waitKey(1) & 0xFF == ord('q'):
              break
  
      except ValueError as ve:
          print("ValueError:", ve)
          # Skip this frame and continue to the next one
          continue
      except Exception as e:
          print("An error occurred:", e)
          break
  
  # Clean up
  cv2.destroyAllWindows()
  drone.stop_video_stream()
  

  error::

  Actual frame shape: (31621,) ValueError: cannot reshape array of size 31621 into shape (10540,3) Packet frame bytes size: 45509 First 100 bytes of frame data: bytearray(b"\x00\x00\x00\x01A\x9a\x00\x10\x00 #\xbf\xf4 \xb7\xe8\xe0\xd3\xb5\x87\xe3\xb8\x0c\xc8\xecN\xe1C\xb4p\x18\xb682 \xb4ef\x15\xc3B\t\xd3^z\x94iF\x05\x89\x1f\xd0\xd3\x1f\xa1\xe7\x12 \\\'\x8f2\t\x017[`l\x1c{[TA\x8eL\xb6\xf7\xd0/\xc9\xb1\xfa\xa2\xc1\xbdw\x98fd\x86\x84\xbcB$\x1d*q\xf7\x02\x1c") Actual frame shape: (45509,) ValueError: cannot reshape array of size 45509 into shape (15169,3) Packet frame bytes size: 20981 First 100 bytes of frame data: bytearray(b"\x00\x00\x00\x01A\x9a\x00\x12\x00$!\x0f\xe2\xb8\xe0\xfd\x0c\xfbR\xd5.\x18\x94L>\xc6\xaf\xa6\xbaN\xf7\x83^M\xff`Q\xc1\xf7\x95u\xb2\xe00\x14\x92z\x94\xf2V\xafe~\xc4\xaa\xa0;,^\x8b*\x14\x00\xa9\xea\xb8=\xc0t\xd3a\xbe. \'\xbf\xac\xd7\xf7\x84\x83\x11\xe2\xc9\x80\x1a\xe1G\x89\xf9\xc4\xd1\xdfX\xfc\xcd\x98\xe3u\xed") Actual frame shape: (20981,) ValueError: cannot reshape array of size 20981 into shape (6993,3) Packet frame bytes size: 23269

  i am trying to stream the video from my drone using ffmpeg-python and opencv

• Convert m3u8 file to mp4 file in React Native Expo

  12 mai, par DRx

  How can I convert m3u8 file to mp4 file in React Native Expo? I have tried to convert m3u8 file to mp4 using FFmpegKit but I have this errors:

  'Cannot read property 'getLogLevel' of null' and 'Cannot read property 'ffmpegSession' of null'

  Also building with this package failing (Could not determine the dependencies of task ':ffmpeg-kit-react-native:compileDebugAidl'.).

  Is there a simple and easy way to convert m3u8 file in React Native Expo?

  Code I have used:

  import { FFmpegKit } from 'ffmpeg-kit-react-native';
  export async function converterToMp4() {
      try {
          await FFmpegKit.executeAsync(`-i ${m3u8FileUri} ${mp4FileUri}`)
  
      } catch(err) {
          console.log(err)
      }
  }