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• Converting series of images with ffmpeg results in black video [migrated]

  27 avril 2013, par Marco Gagliardi

  I've just downloaded ffmpeg since it seems to perfectly match my needs (make a video from a set of pictures). I'm currently playing around with some examples just to get started and there's something weird happening that I can't explain.
  I'm trying this command (provided in the official documentation) :

  ffmpeg -f image2 -pattern_type glob -i 'foo-*.jpeg' -r 12 -s WxH foo.avi

  on a data set of 10 jpg pictures (of course I changed the pattern with '*.jpg'). The video seems to be encoded correctly but it's simply too fast to be sure about that (anyway it stops on the last frame that corresponds to the last picture). In order to get a longer video i thought to low the frame rate from 12 to 1 (one sec each picture) or 0.5 (2 sec each one) and so on.. no way ! with low rate values even if the video is played the pictures are simply not displayed. The player (VLC in my case) just shows a blank/empty video for a few seconds.

  Am I making something wrong or have I misunderstood the -r parameter ? Is it something related to codecs involved ? Finally.. How can i get each picture displayed for 1 or 2 seconds ?

  Here's the output :

  MacBook-Pro$ ffmpeg -f image2 -pattern_type glob -i '*.jpg' -r 1 -s 200x300 foo.avi
  
  ffmpeg version N-52517-g1e4f75d Copyright (c) 2000-2013 the FFmpeg developers
  
    built on Apr 27 2013 19:41:11 with llvm-gcc 4.2.1 (LLVM build 2336.11.00)
  
    configuration: --disable-yasm
  
    libavutil      52. 27.101 / 52. 27.101
  
    libavcodec     55.  6.100 / 55.  6.100
  
    libavformat    55.  3.100 / 55.  3.100
  
    libavdevice    55.  0.100 / 55.  0.100
  
    libavfilter     3. 61.100 /  3. 61.100
  
    libswscale      2.  2.100 /  2.  2.100
  
    libswresample   0. 17.102 /  0. 17.102
  
  Input #0, image2, from '*.jpg':
  
    Duration: 00:00:00.40, start: 0.000000, bitrate: N/A
  
      Stream #0:0: Video: mjpeg, yuvj422p, 2560x1920 [SAR 1:1 DAR 4:3], 25 fps, 25 tbr, 25 tbn, 25 tbc
  
  File 'foo.avi' already exists. Overwrite ? [y/N] y
  
  Output #0, avi, to 'foo.avi':
  
    Metadata:
  
      ISFT            : Lavf55.3.100
  
      Stream #0:0: Video: mpeg4 (FMP4 / 0x34504D46), yuv420p, 200x300 [SAR 2:1 DAR 4:3], q=2-31, 200 kb/s, 1 tbn, 1 tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (mjpeg -> mpeg4)
  
  Press [q] to stop, [?] for help
  
  frame=    2 fps=0.0 q=2.0 Lsize=      43kB time=00:00:02.00 bitrate= 177.1kbits/s dup=0 drop=8    
  
  video:38kB audio:0kB subtitle:0 global headers:0kB muxing overhead 15.099197%
  
  MacBook-Pro$ 

• Speeding up video to image conversion

  16 août 2014, par Timo Theobald

  I use

  call(['avconv', '-i', 'video.mp4', '-vsync', '1','-r', '1','-an','-y','%5d.jpg'])

  in Python. It works, but it goes through the videofile in realtime. How to speed this up, so getting 60 pictures all in all, each second of the video file does not take 1 minute but less.

• FFmpeg First 2 Seconds of Video Not Showing

  18 janvier 2016, par Pamela

  This code works fine for some audio files (makes a slideshow of JPG pictures with a PNG watermark and MP3 audio, while maintaining aspect ratio) but for this audio file, the pictures are not showing for the first two seconds or so of the video :

  ffmpeg -y -framerate 1/12 -i "media/%03d.jpg" -i "media/audio.mp3" -loop 1 -i "media/watermark.png" -filter_complex "[0:v]scale=iw*min(3840/iw\,2160/ih):ih*min(3840/iw\,2160/ih), pad=3840:2160:(3840-iw)/2:(2160-ih)/2[ss]; [ss][2:v] overlay=main_w-overlay_w-10:main_h-overlay_h-10:shortest=1[out]" -map "[out]" -map 1:a -c:v libx264 -r 24 -preset veryfast -tune stillimage -pix_fmt yuv420p -c:a copy -map_metadata -1 "media/video.mkv" -report

  I tried converting the audio into different formats of MP3, tried changing bitrates, changed audio to stereo, and even tried converting it to a WAV. None of these things worked.

  Here are the report results for when I run this command.

  If it makes a difference, I’m using Ubuntu 14.04 and FFmpeg version N-77455-g4707497 (latest version).