Video processing hangs indefinitely with corrupted video segments

[Archkik]

When processing a video containing corrupted segments, the subclipped function (and other methods depending on get_frame) can hang indefinitely without raising an error or timeout. This behavior seems to be caused by the underlying frame_function implementation, which does not handle corrupted frames or set a timeout for frame decoding.

video_path = "path_to_corrupted_video.mp4"  
video = VideoFileClip(video_path)
try:
    sub_clip = video.subclipped(43, 50)
except Exception as e:
    print(f"Error: {e}")

Expected Behavior

Raise an error indicating that the frame cannot be decoded, or
Raise a Timeout error

Actual Behavior

The function hangs indefinitely without raising an error, likely due to the underlying frame decoding stalling when encountering corrupted frames.

Specifications

• Python Version: 3.11
• MoviePy Version: 2.1.1
• Platform Version: Windows10

[Archkik]

from moviepy import VideoFileClip
video_path = "output_video1.mp4"  
video = VideoFileClip(video_path)
try:
    sub_clip = video.subclipped(6, 8)
    print("OK")
except Exception as e:
    print(f"Error: {e}")

output_video1.zip

[OsaAjani]

I cannot reproduce under Linux with version 2.1.2, can you check on your end and verify if the issue still exists.

[OsaAjani]

@Archkik can you reproduce it with latest version on master ?

[Archkik]

@OsaAjani I tested with MoviePy 2.1.2 on Windows 10, using the same corrupted video sample from my previous comment，and the issue still persists. This time, instead of hanging immediately, it outputs some video information before getting stuck indefinitely. It seems like the behavior has slightly changed, but the underlying issue with corrupted video segments causing the process to freeze remains.

{'video_found': True, 'audio_found': True, 'metadata': {'major_brand': 'isom', 'minor_version': '512', 'compatible_brands': 'isomiso2avc1mp41', 'encoder': 'Lavf60.14.100'}, 'inputs': [{'streams': [{'input_number': 0, 'stream_number': 0, 'stream_type': 'video', 'language': None, 'default': True, 'size': [1280, 720], 'bitrate': 4190, 'fps': 30.0, 'codec_name': 'h264', 'profile': '(Main)', 'metadata': {'handler_name': 'VideoHandler'}}, {'input_number': 0, 'stream_number': 1, 'stream_type': 'audio', 'language': None, 'default': True, 'fps': 44100, 'bitrate': 123, 'metadata': {'handler_name': 'SoundHandler'}}], 'input_number': 0}], 'duration': 16.0, 'bitrate': 4320, 'start': 0.0, 'default_video_input_number': 0, 'default_video_stream_number': 0, 'video_codec_name': 'h264', 'video_profile': '(Main)', 'video_size': [1280, 720], 'video_bitrate': 4190, 'video_fps': 30.0, 'default_audio_input_number': 0, 'default_audio_stream_number': 1, 'audio_fps': 44100, 'audio_bitrate': 123, 'video_duration': 16.0, 'video_n_frames': 480} C:\Users\22861\AppData\Local\Programs\Python\Python311\Lib\site-packages\imageio_ffmpeg\binaries\ffmpeg-win64-v4.2.2.exe -i C:\Users\22861\Videos\output_video1\output_video1.mp4 -loglevel error -f image2pipe -vf scale=1280:720 -sws_flags bicubic -pix_fmt rgb24 -vcodec rawvideo -

[OsaAjani]

For now I simply dont know what we can do about this. Python subprocess read does not seems to implement a timeout and ffmpeg dont seems to raise an error. If someone have an idea fell free to have a go and make a PR !