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• Tools to determine video orientation

  6 avril 2014, par JayLev

  I receive videos from different devices and want to encode them using the correct orientation.

  I've seen some of examples of how to determine the orientation of a video from a iPhone.

  With exiftool and mediainfo I can indeed tell if an iPhone video has to be rotated.

  However, for android videos, both portrait and landscape videos have the same rotation and matrix structure as each other.

  Maybe this is just with my phone, I'm trying to find videos taken from newer droid phones.

  My question however is whether there's other tools or a different way to determine the orientation that'll work with all devices.

  EDIT :
  I just checked a video from a Samsung Galaxy S II, and I can get the orientation from exiftool. So it's not a problem with all android phones.
  My android phone is a HTC Desire running on android 2.2.

  And actually (I didn't even notice before) a portrait video will not be correctly oriented even when playing on the phone. So I guess it's not about the tools, the orientation data just doesn't seem to be correct at all.

• What really causes stutter in RTSP stream ? Live555/FFMPEG server, Android Client

  2 mars 2015, par Wajih

  Ok,I am going to ask you a few simple questions after I had some lengthy arguments with my manager. I am not going to post lengthy code snippets, but just try to explain what I know and I know someone can guide me.

  1. I am working on a opensource project that contains two different streaming servers, FFMPEG and Live555. Both stream H264 video over UDP
  2. I can easily switch between the two and the client seems to understands which server it is talking to.
  3. At the android client, the code uses hardware decoding via MediaCodec apis for Android SDK 4.1.2

  From this point onward I have been arguing with my manager that video breakage and stutter are two different things, where breakage is caused by packet loss over the network. And stutter is completely different, though my knowledge about stutter is limited, I could not argue much so I turned to SO.

  I am not really sure as to why stutter is frequently occuring. Even at 0% 1% packet loss, packets encoded as H264 stream are being received at Android Client - Client tries to decode the stream and render it. I did not expect stutter to occur so frequently and so badly. I feel it sometimes even induces lag or delay in video play by couple of seconds. Stutter occurs after almost every minute or so.

  I am not really into H.264 streaming or H264 codec - both are new to me.
  May be someone can guide me in the right direction, any possibility that stutter occurs due to re-transmission of UDP packets ?

• How to run FFMPEG with —enable-libfontconfig on Amazon Lambda

  20 avril 2024, par Adrien Kaczmarek

  Problem

  


  I want to run FFmpeg on AWS Lambda (Amazon Linux 2) with the configuration --enable-libfontconfig enable.

  


  Situation

  


  I already have FFmpeg running on AWS Lambda without the configuration --enable-libfontconfig.

  


  Here is the step I took to run FFmpeg on AWS Lambda (see official guide) :

  


  

  • Connect to Amazon EC2 running on AL2 (environment used by Lambda for Python 3.11)

  


  • Download and package FFmpeg from John Van Sickle

  


  • Create a Lambda Layer with FFmpeg

  


  


  Unfortunately, the version built by John Van Sickle doesn't have the configuration --enable-libfontconfig enabled.

  


  Unsuccessful Trials

  


  I tried to rebuilt it from scratch following the installation guide but without success (and the guide doesn't install font related dependencies)

  


  I tried to install it with brew but the command brew install ffmpeg didn't succeed on AL2.

  


  I tried to install ffmpeg from ffmpeg-master-latest-linux64-gpl.tar.xz. Unfortunately, this build of ffmpeg doesn't run on AL2 :

  


  ffmpeg: /lib64/libm.so.6: version `GLIBC_2.27' not found (required by ffmpeg)
ffmpeg: /lib64/libpthread.so.0: version `GLIBC_2.28' not found (required by ffmpeg)
ffmpeg: /lib64/libc.so.6: version `GLIBC_2.27' not found (required by ffmpeg)
ffmpeg: /lib64/libc.so.6: version `GLIBC_2.28' not found (required by ffmpeg)


  


  Any help would be greatly appreciated,

  


  Please make sure your answer is up to date and tested. Too many answers out there are auto-generated, too generic, or simple redirect without context.

  


  Thank you