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• How to record custom videos in Android [on hold]

  27 novembre 2013, par Chirry

  Context :

  Right now I have an App which takes the video from the camera and put some custome bitmaps on the same SurfaceView.

  Question :

  What I'd like is to record a video with the camera view and the custom Bitmaps on it.

  I have heard about AndroidFFmpeg third party codec to record videos, but I don't know how, I mean, is there any function on the AndroidFFmpeg to record videos in Android ?

  Hope you can help me with one this as there is not much information on the internet !

• Adding cross fade between concatenated videos

  6 novembre 2022, par SyndicatorBBB

  I'm using the following command to concat multiple videos together :

  


  ffmpeg -i 1.mp4 -i 2.mp4 -i 3.mp4 -f lavfi -t 0.1 -i anullsrc -filter_complex "[0:v]scale=3840:2160:force_original_aspect_ratio=decrease,pad=3840:2160:-1:-1,setsar=1,fps=30,format=yuv420p[v0]; [1:v]scale=3840:2160:force_original_aspect_ratio=decrease,pad=3840:2160:-1:-1,setsar=1,fps=30,format=yuv420p[v1]; [2:v]scale=3840:2160:force_original_aspect_ratio=decrease,pad=3840:2160:-1:-1,setsar=1,fps=30,format=yuv420p[v2]; [v0][3:a][v1][3:a][v2][3:a]concat=n=3:v=1:a=1[v][a]" -map "[v]" -map "[a]" -c:v libx264 -c:a aac -movflags +faststart output3.mp4


  


  How can I modify my command so that I can include cross fade transition between each video ? Notice I need a constant duration of fade between all the videos, no need special effect between two videos.
Also I don't care about audio, only care about the transitions between videos.

  


  Is there a generic way that I don't need to specify the exact time when to start the next transition ? Like saying between each video do cross fade transition.

  


• Rebuilding Website for sharing videos

  22 novembre 2015, par Léo Le Gall

  Some friends and I run a sport forum with a decent user base. A lot of users wanted the ability to share video clips of their tricks. We didn’t really think anyone would use a video website that we made, so I built a really simple one just to see if the users would really use it. I hosted the video site on a $10 VPS, and it got blown away. The site was literally garbage, it was not visually appealing and the performance was just sad. Just as expected really, since this was just a test site. Since our test project was a success, we want to create a new and more polished site for the videos.

  The website is really simple, and probably not optimized in any way at the moment. I will try to explain in details what the website does. The user uploads some video files in format X, the website combines them and converts (using ffmpeg) the final video to mp4(so it can be served with a html5 video player). The users gets a link (example.com/randomvideo) where he can see the video through a html5 player serving the mp4 file(just default html5, nothing fancy). The videos only contains highlights, and the final video is always under 1 minute, most are around 30 seconds.

  Currently everything happens on the same server, both the video processing and the video serving. I can try to show how it works :

  1. User uploads some videos
  2. Servers stores the videos in a new random folder
  3. Combine videos and convert to mp4 (ffmpeg)
  4. Move final video(random name) to directory containing processed videos
  5. Store the name of the video file in the database (for website to serve it)
  6. Delete directory used to process the videos

  I want to rebuild the website’s architecture to make it able to scale and handle heavy load. I have never done this before and I am currently making a plan how to do this. My plan is at the moment :

  1. Seperate servers for processing videos and viewing videos (all VPS in the start)
  2. Utilize content delivery network for serving static files
  3. Utilize load balancers both for servers proccesing and serving

  I don’t really know what I should do with database(s). Can I do with one database or should use more ? They do not need to store sensitive information, since the auth in done through an API. They only need store information about the videos. I have experience with postgresql, mysql and redis, but I am not limited to those. What would you recommend in terms of scaleability ?

  I will appriciate all the feedback I can get regarding my plan and what to do about databases. I know this might be a bit vague, so please ask me if I have forgotten anything imporant. Thanks for reading.