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• x264 Encoding use x264_picture_clean crash

  5 mai 2017, par Wong Sam

  When I use iphone encoding CMSampleBufferRef To H264, it offen crash at x264_picture_clean I dont't know how to deal it

  enter image description here

  x264_picture_t* pPic_in; 
  

  here is my init about pPic_in

  pPic_in = (x264_picture_t*)malloc(sizeof(x264_picture_t));
  pPic_out = (x264_picture_t*)malloc(sizeof(x264_picture_t));
  
  x264_picture_init(pPic_out);
  
  x264_picture_init(pPic_in);
  x264_picture_alloc(pPic_in, csp, pParam->i_width, pParam->i_height);
  
  pPic_in->img.i_stride[0] = width;
  pPic_in->img.i_stride[1] = width / 2;
  pPic_in->img.i_stride[2] = width / 2;
  pPic_in->img.i_plane = 3;
  

  and i set data here

      picture_buf = yuv420_data;
      pPic_in->img.plane[0] = picture_buf;
      pPic_in->img.plane[1] = picture_buf + y_size;
      pPic_in->img.plane[2] = picture_buf + y_size*5/4;
  

  it looks well , when i run it on my iphone,but sometimes it will crash at

  x264_picture_clean
  

  here is more detail abuot pPic_in when crash occer enter image description here

  Thank u very much

• x264 Encoding use x264_picture_clean crash

  5 mai 2017, par Wong Sam

  When I use iphone encoding CMSampleBufferRef To H264, it offen crash at x264_picture_clean I dont't know how to deal it

  enter image description here

  x264_picture_t* pPic_in; 
  

  here is my init about pPic_in

  pPic_in = (x264_picture_t*)malloc(sizeof(x264_picture_t));
  pPic_out = (x264_picture_t*)malloc(sizeof(x264_picture_t));
  
  x264_picture_init(pPic_out);
  
  x264_picture_init(pPic_in);
  x264_picture_alloc(pPic_in, csp, pParam->i_width, pParam->i_height);
  
  pPic_in->img.i_stride[0] = width;
  pPic_in->img.i_stride[1] = width / 2;
  pPic_in->img.i_stride[2] = width / 2;
  pPic_in->img.i_plane = 3;
  

  and i set data here

      picture_buf = yuv420_data;
      pPic_in->img.plane[0] = picture_buf;
      pPic_in->img.plane[1] = picture_buf + y_size;
      pPic_in->img.plane[2] = picture_buf + y_size*5/4;
  

  it looks well , when i run it on my iphone,but sometimes it will crash at

  x264_picture_clean
  

  here is more detail abuot pPic_in when crash occer enter image description here

  Thank u very much

• Manually generate "empty" h264 p-frame

  26 avril 2017, par leavittx

  Let's call a p-frame frame empty if it doesn't change any pixels in the currently decoded video (i.e. no motion vectors, nothing).

  What I need is to be able to manually insert empty p-frame into the video stream on request (need to send frames to the streaming client with a constant framerate, however the frame source on the streaming server can supply frames with a different/lower one).

  So I need to be able to correctly form the byte sequence which represents the empty p-frame for the current resolution (I wonder which other parameters could be needed?)

  Ideally, I prefer to have an encoder-independent solution, since I use two different ones: nvenc via Nvidia Video SDK and x264 via FFmpeg.

  Where should I look to?

• Manually generate "empty" h264 p-frame

  26 avril 2017, par leavittx

  Let's call a p-frame frame empty if it doesn't change any pixels in the currently decoded video (i.e. no motion vectors, nothing).

  What I need is to be able to manually insert empty p-frame into the video stream on request (need to send frames to the streaming client with a constant framerate, however the frame source on the streaming server can supply frames with a different/lower one).

  So I need to be able to correctly form the byte sequence which represents the empty p-frame for the current resolution (I wonder which other parameters could be needed?)

  Ideally, I prefer to have an encoder-independent solution, since I use two different ones: nvenc via Nvidia Video SDK and x264 via FFmpeg.

  Where should I look to?

• How to achieve 2 pass encoding using x264 ?

  6 avril 2017, par Kim Kardashian

  is there a parameter in the x264_param_t structure or do I have to send frames to x264 dll twice.. ? Because I just use encoder_encode function and that returns nal units . Im guessing it should be a combination of a parameter and using encoder_encode twice.

  Here is how i initialize params and link to libx264

      InitializeSettings(){
      x264_param_default_preset(&m_pXParam, "medium", "zerolatency");
      x264_param_apply_profile(&m_pXParam, "baseline");
      m_pXParam.i_width = cx;
      m_pXParam.i_height = cy;
      m_pXParam.i_fps_num = fps;
      m_pXParam.i_fps_den = 1;
      // rate control
      m_pXParam.i_keyint_max = fps - 5;
      //m_pXParam.rc.f_rf_constant_max = fps + 5;
      // rate control
      m_pXParam.rc.i_qp_constant=18;
      m_pXParam.rc.i_qp_min=18;
      m_pXParam.rc.i_qp_max=18;}
  
      x264_picture_alloc(&m_xPicture, X264_CSP_I420 , m_pXParam.i_width, m_pXParam.i_height);
      m_xPicture.img = x264img;
      m_iframe_size = x264_encoder_encode(m_xEncoder, &m_xNals, &m_iNal, &m_xPicture, &m_xPictureOut);  
  

  @nobody555 Thanks! I had another question about x264_param_apply_fastfirstpass function:

  /* x264_param_apply_fastfirstpass:
   *      If first-pass mode is set (rc.b_stat_read == 0, rc.b_stat_write == 1),
   *      modify the encoder settings to disable options generally not useful on
   *      the first pass. */
  

  what options are they talking about ?