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• Video streaming with ipCamera in iphone

  6 juillet 2013, par user1120998

  I am developing app for the connecting ip camera and get stream. I don't know how to convert stream into video. I have analysed, and then i tried FFMPEG library. But i did not get correct url for ios with FFMPEG. Can you suggest the guide for implementation.

  Now i am integrating ffmpeg, when i integrated i got the error when opening avformat_find_stream_info() function. I used the increase or less the value of pFormatCtx->max_analyze_duration. But no solution for this.

  [mjpeg @ 0x8b85000] max_analyze_duration 1000 reached at 40000
  [mjpeg @ 0x8b85000] Estimating duration from bitrate, this may be inaccurate

  Pls help how to solve this.

• Display YUV420P video using OpenGLES on iPhone

  25 décembre 2014, par user3487978

  I am writing an app displaying YUV420p video using ffmpeg library on iPhone, every thing works fine, but the OpenGL color is a little strange, see picture, the bellow image is displaying using AVPicture in RGB format, above is using AVPicture in YUV format.
  any ideas ?

  my shader

  varying highp vec2 varTexcoord;
  
  uniform sampler2D SamplerY;
  
  uniform sampler2D SamplerUV;
  
  void main (void)
  
  {
  
      mediump vec3 yuv;
  
      lowp vec3 rgb;
  
      yuv.x = texture2D(SamplerY, varTexcoord).r;
  
      yuv.yz = texture2D(SamplerUV, varTexcoord).rg - vec2(0.5, 0.5);
  
      // Using BT.709 which is the standard for HDTV
  
      rgb = mat3(      1,       1,      1,
  
                  0, -.18732, 1.8556,
  
                  1.57481, -.46813,      0) * yuv;
  
      gl_FragColor = vec4(rgb,1.0);
  
  }

  Renderer :

  glActiveTexture(GL_TEXTURE0);
  
  glTexImage2D(GL_TEXTURE_2D,
  
               0,
  
               GL_LUMINANCE,
  
               (GLsizei)model.width,
  
               (GLsizei)model.height,
  
               0,
  
               GL_LUMINANCE,
  
               GL_UNSIGNED_BYTE,
  
               [model.y bytes]);
  
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
  
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
  
  
  
  glActiveTexture(GL_TEXTURE1);
  
  glTexImage2D(GL_TEXTURE_2D,
  
               0,
  
               GL_LUMINANCE,
  
               (GLsizei)model.width/2,
  
               (GLsizei)model.height/2,
  
               0,
  
               GL_LUMINANCE,
  
               GL_UNSIGNED_BYTE,
  
               [model.uv bytes]);
  
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
  
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

  

• What are all the codecs and formats not supported by FFmpeg ?

  4 mars 2020, par Alexander Swann

  We are building a service where we do not know what format/codec a video uploaded by a user is in. Due to the nature of the application, we expect input video formats to be very fragmented, diverse and niche. We are currently using FFmpeg to transcode input formats to a consistent output (e.g. mp4).

  Due to the above scenario, I would like to establish a general list of what formats and codecs are not currently supported by FFmpeg. This is so I can research other open source video transcoding tools which I can utilise to fill in the gaps and allow our service to be more reliable for the user.

  Are there resources online that can help at least get a general idea of what might not be supported by FFmpeg ?