Recherche avancée

Sur d’autres sites (7595)

• Trying to convert code to be compatible with macOS by not using the .exe version of FFmpeg and FFmprobe. Cant open the .mp4 file when i go to run code

  9 juillet 2024, par Bruno Hawkins

  I am attempting to edit some code in python for extracting frames from a video (using parallel processing to make it faster) a friend created that works on windows, so that it can be used on macOS. However, i am running into some issues and i am not sure what the problem is.

  


  Essentially, when i go to run the frame extractor and try to select a video in the formats specified, it wont let me select it.

  


  i have commented my code best i can. i am an amateur programmer so apologies if it is straightforward.

  


  import os
import subprocess
import multiprocessing
import tkinter as tk
from tkinter import ttk, filedialog, messagebox

def extract_frames(video_path, output_folder, fps, start_time, duration, process_number):
    video_name = os.path.splitext(os.path.basename(video_path))[0]
    part_output_folder = os.path.join(output_folder, f"part_{process_number}")
    if not os.path.exists(part_output_folder):
        os.makedirs(part_output_folder)

    # Using 'ffmpeg' instead of 'ffmpeg.exe' for macOS compatibility
    ffmpeg_command = [
        'ffmpeg', '-ss', str(start_time), '-t', str(duration), '-i', video_path, '-vf', f'fps={fps}',
        os.path.join(part_output_folder, f'{video_name}_frame_%07d.png')
    ]

    print(f"Running FFmpeg command: {' '.join(ffmpeg_command)}")

    try:
        process = subprocess.run(ffmpeg_command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        if process.returncode != 0:
            print(f"Cannot process the file {video_path}: {process.stderr.decode('utf-8')}")
            return part_output_folder, 0
    except Exception as e:
        print(f"Failed to run FFmpeg command: {str(e)}")
        return part_output_folder, 0

    frame_count = len([f for f in os.listdir(part_output_folder) if f.endswith('.png')])
    return part_output_folder, frame_count

def worker_function(queue, video_path, output_folder, fps, start_time, duration, process_number):
    result = extract_frames(video_path, output_folder, fps, start_time, duration, process_number)
    queue.put(result)

def parallel_frame_extraction(video_path, output_folder, fps, num_processes):
    # Use 'ffprobe' instead of 'ffprobe.exe' for macOS compatibility
    ffprobe_command = [
        'ffprobe', '-v', 'error', '-select_streams', 'v:0', '-show_entries', 'format=duration', '-of',
        'default=noprint_wrappers=1:nokey=1', video_path
    ]

    try:
        result = subprocess.run(ffprobe_command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        duration = float(result.stdout.strip())
    except Exception as e:
        messagebox.showerror("Error", f"Failed to get video duration: {str(e)}")
        return

    chunk_duration = duration / num_processes
    processes = []
    manager = multiprocessing.Manager()
    queue = manager.Queue()

    if not os.path.exists(output_folder):
        os.makedirs(output_folder)

    for i in range(num_processes):
        start_time = i * chunk_duration
        p = multiprocessing.Process(target=worker_function,
                                    args=(queue, video_path, output_folder, fps, start_time, chunk_duration, i))
        p.start()
        processes.append(p)

    for p in processes:
        p.join()

    global_frame_offset = 0
    while not queue.empty():
        part_output_folder, frame_count = queue.get()
        frame_files = sorted([f for f in os.listdir(part_output_folder) if f.endswith('.png')])
        for i, frame_file in enumerate(frame_files):
            new_name = os.path.join(output_folder,
                                    f'{os.path.basename(video_path)}_frame_{global_frame_offset + i:07d}.png')
            os.rename(os.path.join(part_output_folder, frame_file), new_name)
        global_frame_offset += frame_count
        os.rmdir(part_output_folder)

    messagebox.showinfo("Complete",
                        f"Frame extraction completed for {video_path}. Total frames extracted: {global_frame_offset}")

def start_frame_extraction():
    video_path = filedialog.askopenfilename(filetypes=[("Video files", "*.mp4;*.avi;*.mkv")])
    if not video_path:
        return

    output_folder = output_folder_var.get()
    if not output_folder:
        return

    fps = int(fps_var.get())
    num_processes = int(num_processes_var.get())

    parallel_frame_extraction(video_path, output_folder, fps, num_processes)

if __name__ == "__main__":
    root = tk.Tk()
    root.title("Frame Extraction")

    output_folder_var = tk.StringVar()
    fps_var = tk.StringVar(value="1")
    num_processes_var = tk.StringVar(value="4")

    def browse_output_folder():
        folder_selected = filedialog.askdirectory()
        output_folder_var.set(folder_selected)

    tk.Label(root, text="Output Folder:").grid(row=0, column=0, padx=10, pady=10)
    tk.Entry(root, textvariable=output_folder_var, width=50).grid(row=0, column=1, padx=10, pady=10)
    tk.Button(root, text="Browse", command=browse_output_folder).grid(row=0, column=2, padx=10, pady=10)

    tk.Label(root, text="FPS:").grid(row=1, column=0, padx=10, pady=10)
    tk.Entry(root, textvariable=fps_var, width=10).grid(row=1, column=1, padx=10, pady=10)

    tk.Label(root, text="Number of Processes:").grid(row=2, column=0, padx=10, pady=10)
    tk.Entry(root, textvariable=num_processes_var, width=10).grid(row=2, column=1, padx=10, pady=10)

    tk.Button(root, text="Start Frame Extraction", command=start_frame_extraction).grid(row=3, column=0, columnspan=3,
                                                                                        padx=10, pady=20)

    root.mainloop()


  


  I tried changing the FFmpeg and FFmprobe path formats from

  


  ffmpeg_path = os.path.join(os.path.dirname(__file__), 'ffmpeg-7.0.1-essentials_build', 'bin', 'ffmpeg.exe')
ffprobe_path = os.path.join(os.path.dirname(__file__), 'ffmpeg-7.0.1-essentials_build', 'bin', 'ffprobe.exe')



  


  to

  


  ffmpeg_command = [
    'ffmpeg', '-ss', str(start_time), '-t', str(duration), '-i', video_path, '-vf', f'fps={fps}',
    os.path.join(part_output_folder, f'{video_name}_frame_%07d.png')
]

ffprobe_command = [
    'ffprobe', '-v', 'error', '-select_streams', 'v:0', '-show_entries', 'format=duration', '-of',
    'default=noprint_wrappers=1:nokey=1', video_path
]



  


  I found this online so im not sure if it is the correct thing to do.

  


  Thanks for any help.

  


• Cut .mkv Video using ffmpeg without changing original bitrate

  23 janvier 2021, par benito_h

  I accidently said an unappropriate swear word during an educational video (good start I know). So I would like to remove this section from the .mkv video. However I would like the video and audio bitrate and quality unchanged.

  


  First, I tried cutting the video slightly after the relevant time stamp without reencoding it, using for example

  


  ffmpeg -i input.mkv -ss 00:01:09.200 -c copy -t 4:11 output.mkv


  


  but this way the first couple of seconds seem to get lost.

  


  Is there a way to remove the relevant segment (01:08.800 to 01:09.200) while maintaining the same bitrate / quality for audio and video ? Since only formulas are shown, a slight out-of-sync wouldnt even matter.

  


• subprocess.Popen crashes when run in background

  17 mars 2016, par user2810298

  In a program I’m working with right now, I try to check for the version of FFMPEG that is installed on the users machine. This works perfectly fine by using subprocess.Popen when run in the foreground OR when run in a detached screen.

  However, when you run it in the background without screen (e.g. COMMAND &> /dev/null &) this process crashes the program. (see below) I’ve seen some people having similar issues on the web, but I still can’t seem to fix this...

  I’ve Any ideas ?

  version_ffmpeg = subprocess.Popen(["ffmpeg","-version"],stdout=subprocess.PIPE,stderr=None)
  
  
  
  f_out = version_ffmpeg.communicate()
  
  (then...)
  
  if f_out --> 3rd word contains --> etc.