Recherche avancée

Sur d’autres sites (4489)

• How can I fix choppy ffmpeg RTP streaming over wifi ?

  19 décembre 2015, par awidgery

  I have a Raspberry Pi, with a USB mic and a WiFi dongle dongle connected.

  I’m trying to stream audio only from the Pi, with the intention of receiving the stream over wifi to a custom iOS mobile app using VLCKit. I’m using ffmpeg on the Pi as I need a reasonably low (<2s) latency for this project, and using Icecast/Darkice gave around 15s latency.

  The code executed on the Pi is :

  ffmpeg -f alsa -i plughw:1,0 -acodec libmp3lame -ab 128k -ac 1 -ar 44100  -f rtp rtp://234.5.5.5:1234

  On the Pi end I have a device playing (Christmas !) music constantly into the USB mic for testing purposes. The Pi is only connected by WiFi - not ethernet.

  For testing receiving the stream, I’m using VLC (on a Macbook/iPhone).

  When the Mac is connected through Ethernet, the stream works fine, as you can see here :

  https://goo.gl/photos/HZgNh7z4HgaqHBaP7

  However, when the Mac is connected via WiFi, the stream is choppy, as you can see here :

  https://goo.gl/photos/qjAVH6djqS9Jbvmh6

  You can also see a ping trace from the Mac to the Pi, and the VLC stats. As you can see there doesn’t seem to be a correlation between either of these and the choppiness.

  I’ve tried the VLC iOS app and the choppiness is the same as the Mac on WiFi.

  How can I decrease/remove this chop, even if doing so increases latency a bit ?

• avformat/mov : Add support for exporting Video Extension Usage info

  30 mai 2024, par Derek Buitenhuis

  avformat/mov : Add support for exporting Video Extension Usage info
  This box is provided by files created by the Apple Vision Pro, as well
  
  as the iPhone 15+ when capture for Vision Pro is enabled.
  The boxes are a mix of things documented by Apple in some PDFs, their
  
  API docs, and reverse engineering. Ideally we will have a real spec
  
  one day.
  Links :
  
    * https://developer.apple.com/av-foundation/Stereo-Video-ISOBMFF-Extensions.pdf
  
    * https://developer.apple.com/documentation/videotoolbox/kvtcompressionpropertykey_horizontaldisparityadjustment
  
    * https://developer.apple.com/documentation/videotoolbox/kvtcompressionpropertykey_stereocamerabaseline
  
    * https://developer.apple.com/documentation/videotoolbox/kvtcompressionpropertykey_heroeye
  Signed-off-by : Derek Buitenhuis <derek.buitenhuis@gmail.com>
  

  • [DH] libavformat/mov.c

• Compile FFMPEG for iOS development

  7 avril 2016, par Alec Gamble

  So I’ve been googling around and there seem to be a lot of answers to this questions... for people who know what they’re doing. Unfortunately I am not one of these people. I had a version of FFMPEG I was using in a project and now I want to port that project to iOS. So I have a version of FFMPEG with LAME installed on my desktop and in my C++ application I was just accessing this through the command line via the system() method. I also just downloaded the FFMPEG iOS build from here :

  https://github.com/kewlbear/FFmpeg-iOS-build-script

  and the gas-preprocessor from the link on that page but I’m unsure as to what to do with it now and how to get it to a state where I would be able to compile a basic FFMPEG test to my iPhone.

  ---

  I tried adding the libraries as mentioned in :
  How to Build FFMpeg as iOS Framework so my project hierarchy looks like :

  

  but when I do :

  #import <libavcodec></libavcodec>avcodec.h> as suggested

  or any other import I can think to do it always errors me out saying it can’t find it. I’m not sure if this is because I’m not using search paths correctly or my import line is wrong or what...