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• Architecture of video-based service for mobile phones

  27 juin 2015, par David Azar

  I guess this is more of a conceptual question than a technical one.

  I’m trying to figure out the best way to upload short videos to a server and also be able to download them and watch them on both Android and iOS.

  Lets focus on Android for the moment.

  I’ve done some experiments, and my results have been :

  • I’m able to compress 12-14MB video down to 500KB using FFMPEG lib with pretty good results in quality, but it takes about 12 seconds.

  • Next, im uploading those videos to my Parse backend as ParseFile to store them.

  • Finally, i can download them and watch them with no problem using a VideoView widget.

  Now, for the tests i’ve been running, these are great results. But i want to see if there is a better way to manage and scale all of this.

  My questions are :

  • Is there a better, lighter way to compress video ?

  • Is Parse the right way to go ?

  • How can i stream videos instead of downloading them and storing the on local storage before playing them ? i know this will cause my app to use significant space on disk and i dont want that.

  • How do big companies do this kind of tasks ?

  I’ve heard Amazon S3 is a cool thing for projects like this one, also Google Cloud Platform. I want to understand the best approach before building everything so i can do it the right way and also, provide the absolute best user experience for watching these videos.

• c# using pipes to get output stream

  1er janvier 2017, par lilscarecrow

  I am trying to pipe youtube-dl output to ffmpeg as input, but cannot seem to get the piping part to work. In normal cmd, I can do something like

   C:\YT\youtube-dl.exe -o - https://www.youtube.com/watch?v=L4aLQ0ki9Tk | ffmpeg -i pipe:0 -f asf pipe:1 

  but in c# this doesn’t work. Currently, I have c# create 2 processes :

  one for youtube-dl

  C:\YT\youtube-dl.exe -o - https://www.youtube.com/watch?v=L4aLQ0ki9Tk

  and another for ffmpeg

  ffmpeg  -i {yt.StandardOutput} -f s16le -ar 48000 -ac 2 pipe:1

  The problem is with the {yt.StandardOutput} (where yt is the process name of the youtube-dl process and -i specifies the input file/stream). Using pipe:0 doesn’t work either and I am not sure how to link the piped output of the first to the input of the second.

• How to create video with dynamic pictures like Facebook Friend's Day video

  21 février 2019, par Vinicius

  How to create a video with pictures from a user just like Facebook does with their Facebook Friend’s day video ?

  Example : https://www.youtube.com/watch?v=mNWJ_XxfQfU

  The intention is to generate this sort of video with images that a visitor will upload to a website. FFMPEG does support images animation but it seems that a bit of 3d animations like the above needs ages to be done with FFMPEG. I wonder if there is an alternative to FFMPEG that can generate this sort of animations, or maybe a software like After Effects that can either generate a template that can be used on ffmpeg (or any command line alternative) or has its own command-line interface that can be executed in a linux machine to do such thing.

  Basically, the user would upload the pictures, the server would crop them to have the same size and then it would convert it to a video like the one mentioned above.