ffmpeg: concatenating with image sequences and audio

How to assemble multiple image sequences and audio files into 1 video file.

Assumptions

• all my images in image sequences are the same dimensions and format (I grabbed a sample video from http://techslides.com/sample-webm-ogg-and-mp4-video-files-for-html5)

• all my audio files are the same format

• ffmpeg version info is:

  ffmpeg version N-82143-gbf14393-tessus Copyright (c) 2000-2016 the FFmpeg developers
  built with Apple LLVM version 8.0.0 (clang-800.0.38)
  configuration: --cc=/usr/bin/clang --prefix=/opt/ffmpeg --extra-version=tessus --enable-avisynth --enable-fontconfig --enable-gpl --enable-libass --enable-libbluray --enable-libfreetype --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopus --enable-libschroedinger --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzmq --enable-version3 --disable-ffplay --disable-indev=qtkit --disable-indev=x11grab_xcb
  libavutil 55. 35.100 / 55. 35.100
  libavcodec 57. 65.100 / 57. 65.100
  libavformat 57. 57.100 / 57. 57.100
  libavdevice 57. 2.100 / 57. 2.100
  libavfilter 6. 66.100 / 6. 66.100
  libswscale 4. 3.100 / 4. 3.100
  libswresample 2. 4.100 / 2. 4.100
  libpostproc 54. 2.100 / 54. 2.100
  Hyper fast Audio and Video encoder
  usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options] outfile}...
  

Convert Video to Image Sequence:

I need images to work with, so make some!

• images will go into the frames directory with names like frame_0001.png, frame_0002.png etc

ffmpeg -i test7.mp4 frames/frame_%04d.png

Convert Image Sequence back to Video

https://ffmpeg.org/pipermail/ffmpeg-devel/2005-August/000523.html

• -c:v libx264 sets the video codec
• -crf 23 sets the quality
• -pix_fmt yuv420p sets the pixel format to something QuickTime can read
• -r 24 sets input and output framerates
  • input framerate is how fast the images and the sequence are meant to be played back
  • output framerate sets how much time between frames in the output video
  • fast input and slow output results in a slideshow or timelapse
  • slow input and fast output results in duplicate frames (I think)
• -y to overwrite files without asking

ffmpeg -r 30 -i frames/frame_%04d.png -c:v libx264 -pix_fmt yuv420p -crf 23 -r 30  -y video-from-frames.mp4

Convert Image Sequence to Video + add audio track

http://trac.ffmpeg.org/wiki/Create%20a%20video%20slideshow%20from%20images

• -i Bonobo - Kong.mp3 specifies another input stream
• -c:a aac converts audio to AAC format
• -shortest limits the length of the output video to the shortest audio or video stream (in this case, the video stream is shorter)

ffmpeg -r 24 -i frames/frame_%04d.png -i "Bonobo - Kong.mp3" -c:v libx264 -c:a aac -pix_fmt yuv420p -crf 23 -r 24 -shortest -y video-from-frames.mp4

Concatenate multiple image sequences with 1 audio track

Put this into video-input-list.txt. The images in the image sequences must all be the same size and format

file './intro/frame_%04d.png'
file './frames/frame_%04d.png'
file './outro/frame_%04d.png'

then run the command:

• -f concat tells ffmpeg to use the concat filter
• -safe 0 has something to do with letting ffmpeg read relative paths in the text file

ffmpeg -r 24 -f concat -safe 0 -i video-input-list.txt -i "Bonobo - Kong.mp3" -c:v libx264 -c:a aac -pix_fmt yuv420p -crf 23 -r 24 -shortest -y video-from-frames.mp4

Concatenate multiple images sequences and concatenate multiple audio tracks

Put this into audio-input-list.txt.

file 'big_trash_tv_hit.aif.mp3'
file 'recording.mp3'
file 'vocoded-note.aif.mp3'
file 'Bonobo - Kong.mp3'

then run the command:

• remember to specify -f concat -safe 0 again before the second input source -i audio-input-list.txt

ffmpeg -r 24 -f concat -safe 0 -i video-input-list.txt -f concat -safe 0 -i audio-input-list.txt -c:a aac -pix_fmt yuv420p -crf 23 -r 24 -shortest -y video-from-frames.mp4

This does what I am looking for!

References

This page is helpful: https://trac.ffmpeg.org/wiki/Concatenate