Recherche avancée

Sur d’autres sites (15351)

• convert code which uses javax.sound.sampled in android

  6 avril 2013, par adityag

  I want to mix two audio files in android. First a song from library and second a sound recorded from mic.

  To begin with, I tried doing it on desktop using JS Resources Audio concat Program

  Using this code, I can mix/merge/overlap 2 sound wav files on desktop when i use float mix mode (-f).

  Now I was trying to do this in android environment. But found that javax.sound.sampled.* ; used in this code is not supported by android.

  Can anyone guide me how to deal with this situation ?

  Thanks,

  -Aditya.

  PS : other approach i tried is trying to use some ffmpg. But frankly, I couldnt understand how to make it work to suit my requirement :(

• avformat/matroskaenc : Avoid unnecessary seek

  2 mai 2020, par Andreas Rheinhardt

  avformat/matroskaenc : Avoid unnecessary seek
  The Matroska muxer has a pair of functions designed to write master
  
  elements whose exact length is not known in advance : start_ebml_master()
  
  and end_ebml_master(). The first one of these would write the EBML ID of
  
  the master element that is about to be started, reserve some bytes for
  
  the length field and record the current position as well as how many
  
  bytes were used for the length field. When writing the master's contents
  
  is finished, end_ebml_master() gets the current position (at the end of
  
  the master element), seeks to the length field using the recorded
  
  position, writes the length field and seeks back to the end of the
  
  master element so that one can continue writing other elements.
  But if one wants to modify the content of the master element itself,
  
  then the seek back is superfluous. This is the scenario that presents
  
  itself when writing the trailer : One wants to update several elements
  
  contained in the Segment master element (this is the main/root master
  
  element of a Matroska file) that were already written when writing the
  
  header. The current approach is to seek to the beginning of the file
  
  to update the elements, then seek to the end, call end_ebml_master()
  
  which immediately seeks to the beginning to write the length and seeks
  
  back. The seek to the end (which has only been performed because
  
  end_ebml_master() uses the initial position to determine the length
  
  of the master element) and the seek back are of course superfluous.
  This commit avoids these seeks by no longer using start/end_ebml_master()
  
  to write the segment's length field. Instead, it is now written
  
  manually. The new approach is : Seek to the beginning to write the length
  
  field, then update the elements (in the order they appear in the file)
  
  and seek back to the end.
  This reduces the ordinary amount of seeks of the Matroska muxer to two
  
  (ordinary excludes scenarios where one has big Chapters or Attachments
  
  or where one writes the Cues at the front).
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
  

  • [DH] libavformat/matroskaenc.c

• Mixed Reality WebRTC without Signalling Server

  25 mai 2021, par SilverLife

  I am trying to find a way, which allows me to use Mixed Reality WebRTC (link to git-repo) without a signalling server.
In detail, I want to create a sdp-file from my ffmpeg Video sender and use this sdp-description in my unity-Project to bypass the signaling process and receive the ffmpeg video stream.
Is there a way of doing so with Mixed Reality WebRTC ? I was already searching for the line of code, where the sdp-file is created within MR WebRTC but I didn´t find it.

  


  I am relatively new to this topic and I am not sure if this works at all but since ffmpeg is not directly compatible with webrtc I was thinking that this might be the most promising approach.