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• ffmpeg produces mp4 I cannot load on latest Safari on iOS

  28 mars 2016, par Michael Heuberger

  When I encode a video with these ffmpeg parameters (based on images), I cannot play that mp4 it produces on latest Safari (inside a tag) inside my iPhone 6s using the latest iOS too :

  ffmpeg 
  
  -r 15.279071668502123 
  
  -f image2 -thread_queue_size 64 
  
  -i /home/michael-heuberger/abcd/frames/%d.webp 
  
  -y 
  
  -an 
  
  -vcodec libx264 
  
  -vf scale=trunc(iw/2)*2:trunc(ih/2)*2 
  
  -crf 16 
  
  -preset fast 
  
  -profile:v baseline 
  
  -pix_fmt yuv420p 
  
  -loglevel warning 
  
  -movflags faststart 
  
  /home/michael-heuberger/abcd/videomail_good.mp4 

  I think the above parameters should be solid. I am adding baseline and yuv420p, yet no luck on Safari 9. Why ?

  This makes it difficult for me to play videomails recorded on www.videomail.io on iOS devices.

  Am I missing something here ? Already did lots of research and tried various combinations, no luck.

  If you want to reproduce that, easy : just record a video on www.videomail.io and after that, copy the link of the recorded video page to your iPhone or just download it for local investigation.

  Any clues very welcome !

• Can I record a video without using UIImagePickerController ?

  24 mai 2016, par SUKIYAKI

  Can I record a video without using UIImagePickerController ?
  Of course without needing to jailbreak or anything else that would cause the App Store to reject the app.

  I think there is a way to access video device not using UIImagePickerController because these camera applications can record video and work on iPhone 2G/3G which utilizes ffmpeg :

  • iVideoCamera
  • iVidCam

  I pick this code up by googling.

  AVFormatParameters formatParams;
  
  AVInputFormat *iformat;
  
  
  
  formatParams.device = "/dev/video0";
  
  formatParams.channel = 0;
  
  formatParams.standard = "ntsc";
  
  formatParams.width = 640;
  
  formatParams.height = 480;
  
  formatParams.frame_rate = 29;
  
  formatParams.frame_rate_base = 1;
  
  filename = "";
  
  iformat = av_find_input_format("video4linux");
  
  
  
  av_open_input_file(&ffmpegFormatContext,
  
                   filename, iformat, 0, &formatParams);

  This code tell me how to open camera device, but I don’t know device path of iPhone.

  How do iVideoCamera and iVidCam record video ?

• Web Based Playback of iOS Videos with Orientation Flag

  3 mars 2012, par shanee

  We just recently created an iPhone app for one of our system that allows users to upload picture and video content to our services. The last major hitch we are running into is how to handle videos that are uploaded in an orientation other than Horizontal Right. Apparently if your playback system does not account for the orientation flag sent with the video then it will play upside down or sideways.

  The correct approach appears to be that the playback system should take the orientation flag into account just prior to playback. This is the way Apple handles it directly on the device as well as through Quicktime.

  SO my first hope is that someone is aware of a web based (HTML5 or Flash) player that is capable of rotating a video during playback based on either the video orientation metadata or based on a passed flag (we already have the necessary flag available in the DB if we need to just pass it manually). If you know of any such player then PLEASE SHARE !

  If you aren't aware of such a player, then has anyone had any luck rotating their videos using FFMPEG or MEncoder ? We did a few hours of testing last week and weren't able to get any decent results from the two heavy hitters mentioned there.

  Failing ALL OF THAT, is it possible to have the iPhone upload a video or image in a specified direction ?

  Any of the three will work for me, but I would prefer to do whatever is standard (if one exists).

  Any help is much appreciated !