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• FFMPEG, how to put h263 in mp4 contain format ? [closed]

  4 mars 2012, par John Nabil

  I managed to encode group of images in h263 codec using ffmpeg, but my problem now , i want to put the result into mp4 container

  Thanks in advance.

• 2011 In Open Source Multimedia

  5 janvier 2012, par Multimedia Mike — Open Source Multimedia

  Sometimes I think that the pace of multimedia technology is slowing down. Obviously, I’m not paying close enough attention. I thought I would do a little 2011 year-end review of what happened in the world of open source multimedia, mainly for my own benefit. Let me know in the comments what I missed.

  The Split
  The biggest deal in open source multimedia was the matter of the project split. Where once stood one project (FFmpeg) there now stands two (also Libav). Where do things stand with the projects now ? Still very separate but similar. Both projects obsessively monitor each other’s git commits and prodigiously poach each other’s work, both projects being LGPL and all. Most features that land in one code base end up in the other. Thus, I refer to FFmpeg and Libav collectively as “the projects”.

  Some philosophical reasons for the split included project stagnation and development process friction. Curiously, these problems are fond memories now and the spirit of competition has pushed development forward at a blinding pace.

  People inside the project have strong opinions about the split ; that’s understandable. People outside the project have strong opinions about the split ; that’s somewhat less understandable, but whatever. After 5 years of working for Adobe on the Flash Player (a.k.a. the most hated software in all existence if internet nerds are to be believed on the matter), I’m so over internet nerd drama.

  For my part, I just try to maintain some appearance of neutrality since I manage some shared resources for the open source multimedia community (like the wiki and samples repo) and am trying to keep them from fracturing as well.

  Apple and Open Source
  It was big news that Apple magnanimously open sourced their lossless audio codec. That sets a great example and precedent.

  New Features
  I mined the 'git log' of the projects in order to pick out some features that were added during 2011.

  First off, Apple’s ProRes video codec was reverse engineered and incorporated into the multimedia libraries. And for some weird reason, this is an item that made the rounds in the geek press. I’m not entirely sure why, but it may have something to do with inter-project conflict. Anyway, here is the decoder in action, playing a video of some wild swine, one of the few samples we have :

  
  
  

  Other new video codecs included a reverse engineered Indeo 4 decoder. Gotta catch ‘em all ! That completes our collection of Indeo codecs. But that wasn’t enough– this year, we got a completely revised Indeo 3 decoder (the previous one, while functional, exhibited a lot of code artifacts betraying a direct ASM ->C translation). Oh, and many thanks to Kostya for this gem :

  
  
  

  That’s the new Origin Xan decoder (best known for Wing Commander IV cinematics) in action, something I first started reverse engineering back in 2002. Thanks to Kostya for picking up my slack yet again.

  Continuing with the codec section, there is a decoder for Adobe Flash Screen Video 2 — big congrats on this ! One of my jobs at Adobe was documenting this format to the outside world and I was afraid I could never quite make it clear enough to build a complete re-implementation. But the team came through.

  Let’s see, there are decoders for VBLE video, Ut Video, Windows Media Image (WMVP/WMP2), Bink audio version ‘b’, H.264 4:2:2 intra frames, and MxPEG video. There is a DPX image encoder, a Cirrus Logic AccuPak video encoder, and a v410 codec.

  How about some more game stuff ? The projects saw — at long last — an SMJPEG demuxer. This will finally allow usage and testing of the SMJPEG IMA ADPCM audio decoder I added about a decade ago. Funny story behind that– I was porting all of my decoders from xine which included the SMJPEG ADPCM. I just never quite got around to writing a corresponding demuxer. Thanks to Paul Mahol for taking care of that.

  Here’s a DFA playback system for a 1995 DOS CD-ROM title called Chronomaster. No format is too obscure, nor its encoded contents too cheesy :

  
  
  

  There’s now a demuxer for a format called XMV that was (is ?) prevalent on Xbox titles. Now the projects can handle FMV files from many Xbox games, such as Thrillville.

  
  
  

  The projects also gained the ability to play BMV files. I think this surfing wizard comes from Discworld II. It’s non-computer-generated animation at a strange resolution.

  
  
  

  More demuxers : xWMA, PlayStation Portable PMP format, and CRI ADX format ; muxer for OpenMG audio and LATM muxer/demuxer.

  One more thing : an AVX-optimized fast Fourier transform (FFT). If you have a machine that supports AVX, there’s no way you’ll even notice the speed increase of a few measly FFT calls for audio coding/decoding, but that’s hardly the point. The projects always use everything on offer for any CPU.

  Please make me aware of features that I missed in the list !

  Continuous Testing
  As a result of the split, each project has its own FATE server, one for FFmpeg and one for Libav. As of the new year, FFmpeg has just over 1000 tests while Libav had 965. This is one area where I’m obviously ecstatic to see competition. Some ad-hoc measurements on my part indicate that the total code coverage via the FATEs has not appreciably increased. But that’s a total percentage. Both the test count and the code count have been steadily rising.

  Google Summer of Code and Google Code-In
  Once again, the projects were allowed to participate in the Google Summer of Code as well as Google Code-In. I confess that I didn’t keep up with these too carefully (and Code-In is still in progress as of this writing). I do know that the project split occurred after FFmpeg had already been accepted for GSoC season 2011 and the admins were gracious enough to allow FFmpeg and Libav to allow both projects to participate in the same slot as long as they could both be mature about it.

  Happy New Year
  Let’s see what we can accomplish in 2012.

• Reduce HLS latency from +30 seconds

  4 juin 2014, par Rick

  Ubuntu 12.04

  nginx 1.2.4

  avconv -version

  avconv version 0.8.10-4:0.8.10-0ubuntu0.12.04.1, Copyright (c) 2000-2013 the Libav developers
  
    built on Feb  6 2014 20:56:59 with gcc 4.6.3
  
  avconv 0.8.10-4:0.8.10-0ubuntu0.12.04.1
  
  libavutil    51. 22. 2 / 51. 22. 2
  
  libavcodec   53. 35. 0 / 53. 35. 0
  
  libavformat  53. 21. 1 / 53. 21. 1
  
  libavdevice  53.  2. 0 / 53.  2. 0
  
  libavfilter   2. 15. 0 /  2. 15. 0
  
  libswscale    2.  1. 0 /  2.  1. 0
  
  libpostproc  52.  0. 0 / 52.  0. 0

  I’m using avconv and nginx to create an HLS stream but right now my latency is regularly well over 30 seconds. After much reading I am aware that HLS has built in latency and that 10s is expected and even preferred but 30s seems quite extreme.

  I’ve seen a lot of discussion on the nginx-rtmp google group, this thread in particular had a lot of suggestions. I have attempted to reduce solve my issue by reducing the hls_fragment and the hls_playlist_length but they haven’t had a significant effect.

  nginx.conf :

  #user  nobody;
  
  worker_processes  1;
  
  
  
  error_log  logs/error.log debug;
  
  
  
  events {
  
      worker_connections  1024;
  
  }
  
  
  
  http {
  
      include       mime.types;
  
      default_type  application/octet-stream;
  
  
  
      sendfile        on;
  
      keepalive_timeout  65;
  
  
  
      server {
  
          listen       8888;
  
          server_name  localhost;
  
  
  
          add_header 'Access-Control-Allow-Origin' "*";
  
  
  
          location /hls {
  
              types {
  
                  application/vnd.apple.mpegurl m3u8;
  
                  video/mp2t ts;
  
              }
  
              root /tmp;
  
          }
  
  
  
          # rtmp stat
  
          location /stat {
  
              rtmp_stat all;
  
              rtmp_stat_stylesheet stat.xsl;
  
          }
  
          location /stat.xsl {
  
              # you can move stat.xsl to a different location
  
              root /usr/build/nginx-rtmp-module;
  
          }
  
  
  
          # rtmp control
  
          location /control {
  
              rtmp_control all;
  
          }
  
  
  
          error_page   500 502 503 504  /50x.html;
  
          location = /50x.html {
  
              root   html;
  
          }
  
      }
  
  }
  
  
  
  rtmp {
  
      server {
  
          listen 1935;
  
          ping 30s;
  
          notify_method get;
  
  
  
          application myapp {
  
              live on;
  
  
  
              hls on;
  
              hls_path /tmp/hls;
  
              hls_base_url http://x.x.x.x:8888/hls/;
  
              hls_sync 2ms;
  
              hls_fragment 2s;
  
  
  
              #hls_variant _low BANDWIDTH=160000;
  
              #hls_variant _mid BANDWIDTH=320000;
  
              #hls_variant _hi BANDWIDTH=640000;
  
          }
  
      }
  
  }

  avconv command :

  avconv -r 30 -y -f image2pipe -codec:v mjpeg -i - -f flv -codec:v libx264 -profile:v baseline -preset ultrafast -tune zerolatency -an -f flv rtmp://127.0.0.1:1935/myapp/mystream