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• FFMPEG Failure - Extracting frames on large file

  25 avril 2018, par Marian Montagnino

  Calling the ffmpeg command :

  ffmpeg -y -ss "00:00:02" -i 5ccaea226acfc1b4b75ccd1a9f09512c.mxf -frames 30 -f image2 -vf "fps=1/1.25,scale='min(420,iw)':-1" video%04d.jpg

  Causes a failure :

  ffmpeg failed: ffmpeg version N-85692-g78a5fc4 Copyright (c) 2000-2017 the FFmpeg developers
  
  built with gcc 4.8.5 (GCC) 20150623 (Red Hat 4.8.5-11)
  
  configuration: --prefix=/tmp/gm-ffmpeg-1.0.4/BUILD/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/tmp/gm-ffmpeg-1.0.4/BUILD/ffmpeg_build/include --extra-ldflags=-L/tmp/gm-ffmpeg-1.0.4/BUILD/ffmpeg_build/lib --bindir=/tmp/gm-ffmpeg-1.0.4/BUILDROOT/gm-ffmpeg-1.0.4-1.el7.centos.x86_64/opt/graymeta/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-nonfree
  
  libavutil 55. 61.100 / 55. 61.100
  
  libavcodec 57. 93.100 / 57. 93.100
  
  libavformat 57. 72.101 / 57. 72.101
  
  libavdevice 57. 7.100 / 57. 7.100
  
  libavfilter 6. 87.100 / 6. 87.100
  
  libswscale 4. 7.101 / 4. 7.101
  
  libswresample 2. 8.100 / 2. 8.100
  
  libpostproc 54. 6.100 / 54. 6.100
  
  [mxf @ 0x2c6da60] broken or empty index
  
  Input #0, mxf, from '/alloc/5ccaea226acfc1b4b75ccd1a9f09512c.mxf':
  
  Metadata:
  
  uid : 27b07007-2dc8-4305-a78a-81a612d78b94
  
  generation_uid : ef5ae870-4075-4513-ea1f-39c0ed197267
  
  company_name : Colorfront
  
  product_name : Transkoder
  
  product_uid : 3a4fe380-0d01-11e4-869f-3cd92b5c1dfc
  
  product_version : 2.7.3.20150121
  
  application_platform: Microsoft Windows 7 Professional Service Pack 1 (Build 7601)
  
  modification_date: 2016-09-09T11:29:39.000000Z
  
  material_package_umid: 0x060A2B340101010501010F20130000008991E1DCEA584837149E72E7F9F0E09D
  
  timecode : 00:00:17;12
  
  Duration: 00:11:58.92, start: 0.000000, bitrate: 150802 kb/s
  
  Stream #0:0: Video: jpeg2000, yuv422p10le(progressive), 3840x2160, SAR 1:1 DAR 16:9, 59.94 fps, 59.94 tbr, 59.94 tbn, 59.94 tbc
  
  Metadata:
  
  file_package_umid: 0x060A2B340101010501010F2013000000F8B3B48BE8044408DDD6303A6D43F566
  
  track_name : Picture
  
  Stream mapping:
  
  Stream #0:0 -> #0:0 (jpeg2000 (native) -> mjpeg (native))
  
  Press [q] to stop, [?] for help
  
  : signal: killed

  I’m not sure how to interpret this error message and why it actually failed. This file is about 90GB large and shot in 4K resolution but 11 seconds long.

• OpenCV - motion detection in large video files

  18 décembre 2023, par M9A

  I have large video files (over a few GB each) that I am trying detect motion on. I am using fairly basic OpenCV code in python with ROI to detect motion in a certain area of the video only. This works absolutely fine but takes absolutely ages to process large files. Is there any way to speed things up ? I am simply just checking to see which file has motion detected in it and will not be outputting a video. The moment the first motion is detected the rest of the file is not checked.

  


  import sys
import cv2

video_path = “video.mp4”

capture = cv2.VideoCapture(video_path)

# Set the first frame as the reference background
_, background = capture.read()

# Define the region of interest (ROI)
x, y, w, h = 1468, 1142, 412, 385
roi = (x, y, x + w, y + h)

while capture.isOpened():
    ret, frame = capture.read()

    if not ret:
        break

    # Extract the region of interest from the current frame
    frame_roi = frame[y:y + h, x:x + w]

    # Calculate the absolute difference between the ROI and the background
    diff = cv2.absdiff(background[y:y + h, x:x + w], frame_roi)
    gray = cv2.cvtColor(diff, cv2.COLOR_BGR2GRAY)
    _, thresh = cv2.threshold(gray, 30, 255, cv2.THRESH_BINARY)

    # Check if motion is detected in the ROI (adjust threshold as needed)
    if cv2.countNonZero(thresh) > 75:
        print("YES")
        break

# Release the video capture object
capture.release()


  


• Camera Rendering Buffers and Stutters When Large Video Files Being Processd with FFmpeg

  20 avril 2023, par TIANYU HU

  When rendering a real-time camera, I use ffmpeg to process a large video file(like 4G or even larger) at the same time. I noticed that the video frames are buffering and stuttering.

  


  Pipeline :

  


  DISPLAY=:0 gst-launch-1.0 filesrc location=/home/user/jellyfish-120-mbps-4k-uhd-hevc-10bit.mkv ! matroskademux name=demux demux.video_0 ! queue ! h265parse ! nvv4l2decoder ! nvvidconv ! xvimagesink

  


  FFmpeg command :

  


  ffmpeg -i ${file_name} -c copy -f segment -segment_time 600 -segment_format_options movflags=+faststart -reset_timestamps 1 ./${file_name}_%02d.mp4 -y

  


  And there are some warning indicated that “a lot of buffers are being dropped” duration stuttering.
pipeline warning picture

  


  The requirement can be summarized as “real-time video rendering has higher priority, and the low rate of large file processing is accepted”, are there any possible solutions of this issue from your perspective ? Thanks in advance.