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• rails streamio-ffmpeg does not find uploaded video files

  26 avril 2016, par Felix

  I try to make a screenshot as thumbnail of a movie while uploading.

  My code looks like this at the moment

  require 'rubygems'
  
  require 'streamio-ffmpeg'
  
  
  
   def uploadMovie
  
     @channels = Channel.all
  
     @vid = Movie.new(movies_params)
  
  
  
     @channel = Channel.find(params[:vid][:channel_id])
  
     @vid.channel = @channel
  
  
  
     if @vid.save
  
       flash[:notice] = t("flash.saved")
  
       movieFile = FFMPEG::Movie.new(@vid.video.to_s)
  
       screenshot = movieFile.screenshot("uploads/screenshot", :seek_time => 10)
  
       render :add
  
     else
  
       render :add
  
     end
  
   end

  But when I do this I got this error :

    No such file or directory - the file 'http://.s3.amazonaws.com/uploads/movie/video/7/2016-04-24_16.26.10.mp4' does not exist

  That should be okay because I upload the movies to Amazon S3 with carrierwave ...

  What’s going wrong in this case ?

• Access pixel data of each frame of a video in Ruby

  23 janvier 2019, par Robin

  I want to be able to read/stream a video with Ruby, on Mac, and be able to get access to the pixel data for each frame.

  What I’ve tried

  • https://github.com/streamio/streamio-ffmpeg

    It’s good at splitting the video into frames, but I don’t know how to get access to the pixel data without saving each frame as an image first (or if it’s possible at all).

  ---

  require 'streamio-ffmpeg'
  
  movie = FFMPEG::Movie.new("flakes.mp4")
  
  
  
  movie.screenshot("screenshots/screenshot_%d.jpg", { custom: %w(-vf crop=60:60:10:10), vframes: (movie.duration).to_i, frame_rate: movie.frame_rate/24 }, { validate: false })`

  ---

  • https://github.com/wedesoft/hornetseye-ffmpeg

    This seemed to have so much potential, but I don’t think it’s maintained anymore, and it’s not meant to be used on MacOS really, so I’m having issues installing it there (headers not found and such, and no way to configure it afaik).

  Any idea what tool or method I could use for this use case ?

• ffmpeg (IMAGE THUMBNAIL 1 frame) how to "choose" compression quality when we use -vframes 1 (how to do like convert -quality 60....)

  25 juillet 2021, par jini

  • PRE-CONTEXT : with ImageMagick, I'm use to do convert -quality 60 1.jpg 1.webp here "quality 60" affect the final size of the output

  


  • CONTEXT : create a poster.webp OR poster.jpg of a movie.mp4

  


  • QUESTION : how can we "achieve" the same compression level choice with ffmpeg when we want 1 frame

  


  • WHAT I TRIED [1] :

  


  ffmpeg -i movie.mp4 -vframes 1 -qmin 0 -qmax 1  0.webp

  


  and ffmpeg -i movie.mp4 -vframes 1 -qmin 50 -qmax 51 50.webp

  


  ==>> both gives the exact same size for the output.

  


  • WHAT I TRIED [2] :

  


  ffmpeg -i movie.mp4 -vframes 1 -b:v 9k bv9k.webp

  


  and ffmpeg -i movie.mp4 -vframes 1 -b:v 1k bv1k.webp

  


  ==>> both gives the exact same size for the output.

  


  what I'm I missing or miss using here ?

  


  Thanks