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• rtpproto : Add an option for writing return packets to the address of the last receive...

  13 août 2013, par Martin Storsjö

  rtpproto : Add an option for writing return packets to the address of the last received packets
  If we’ve received packets on the same socket before, the return
  
  packets are sent to that address. If we’ve only received packets
  
  on the other socket, try to guess the source port for the other
  
  one assuming the basic �1 logic.
  Signed-off-by : Martin Storsjö <martin@martin.st>
  

  • [DH] libavformat/rtpproto.c

• Details about the types of the filtered frame used in FFmpeg

  17 décembre 2015, par sunzhida

  I am new in multimedia analysis.

  I am trying to extract key frames from .mp4 and .flv format videos by using FFmpeg. The problem is that I was confused by the parameters used in the command (Select only I-frames).

  select='eq(pict_type\,I)'

  The parameters are used to choose the types of filtered frame and It can assume one of the following values :

  I P B S SI SP BI

  After searching on Wikipedia, I have got some basic concepts on I, P, B frames but still cannot tell the difference among S, SI, SP and BI. How to decide which type of frame should I use in my command line ?

  [Update]

  I found some of the definitions of these terms in The H.264 Advanced Video Compression Standard, Second Edition.

  • SI : Intra-coded slice used for switching between coded bitstreams
    (H.264)
  • SP : Inter-coded slice used for switching between coded
    bitstreams

• How do I actually use ffmpeg on Android ?

  19 décembre 2013, par slhck

  I have a very basic question regarding Android and ffmpeg. I obtained ffmpeg from http://bambuser.com/opensource and was able to compile it for ARM.

  The results are the binaries (ffmpeg) as well as several libsomething.so files.

  My question is : Is this enough to decode videos ? How do I actually use ffmpeg then ?

  To load the library I have :

  static {
  
      System.load("/data/data/com.package/lib/libavcodec.so");
  
   }

  It loads fine. But what then ?

  
  _{More explanation : I saw other projects where people had their ffmpeg source in a JNI directory in the project. They also created some Android.mk files and some C code along with it. Would I need this as well ? Why would I create the .so files first and then copy the ffmpeg source code again ?}
  

  
  _{I know the NDK and how it should work but I've never seen an example of how one would actually call ffmpeg functions using it, because people seem to be hiding their implementations (which is sort of understandable) but not even giving useful pointers or examples.}
  

  
  _{Let's just say I wanted to decode a video file. Which kind of native methods would I need to implement ? How do I run the project ? Which data types need to be passed ? etc. There are certainly a few people here who have at least done that, I know this from searching for hours and hours.}