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Sur d’autres sites (9474)

  • Video streaming- control frame rate x264

    3 mars 2017, par H.A

    I’m new to video coding, I found this https://github.com/RafaelPalomar/H264LiveStreamer application code very useful to my project. I want to live stream a webcam over RTP . However, I’m having problem selecting the Frame Per Seconds (FPS). below is the function that controls the encoding param.

    void x264Encoder::initilize()
    {
     x264_param_default_preset(&parameters, "veryfast", "zerolatency");
     parameters.i_log_level =  X264_LOG_DEBUG;
     parameters.i_threads = 1;
     parameters.i_width = 640;
     parameters.i_height = 480;
     parameters.i_fps_num = 25;
     parameters.i_fps_den = 1;
     parameters.i_keyint_max = 25;
     parameters.b_intra_refresh = 1;
     parameters.rc.i_rc_method = X264_RC_CRF;
     parameters.rc.i_vbv_buffer_size = 1000000;
     parameters.rc.i_vbv_max_bitrate = 90000;
     parameters.rc.f_rf_constant = 25;
     parameters.rc.f_rf_constant_max = 35;
     parameters.i_sps_id = 7;
     // the following two value you should keep 1
     parameters.b_repeat_headers = 1;    // to get header before every I-Frame
     parameters.b_annexb = 1; // put start code in front of nal. we will remove start code later
     x264_param_apply_profile(&parameters, "baseline");

     encoder = x264_encoder_open(&parameters);
     x264_picture_alloc(&picture_in, X264_CSP_I420, parameters.i_width, parameters.i_height);
     picture_in.i_type = X264_TYPE_AUTO;
     picture_in.img.i_csp = X264_CSP_I420;
     // i have initilized my color space converter for BGR24 to YUV420 because my opencv video capture gives BGR24 image. You can initilize according to your input pixelFormat
     convertContext = sws_getContext(parameters.i_width,parameters.i_height, PIX_FMT_BGR24, parameters.i_width,parameters.i_height,PIX_FMT_YUV420P, SWS_FAST_BILINEAR, NULL, NULL, NULL);
    }

    I’m using VLC as client whatever number i set i_fps_num to, I always get 12-14 FPS. fore example, in VLC Codec tab shows 25 FPS but in Stream statistics tab it shows it only display 13 FPS on average. here is the X264 encoder output

    x264 [debug]: frame=  72 QP=22.24 NAL=2 Slice:P Poc:144 I:97   P:116  SKIP:987  size=1464 bytes
    x264 [info]: frame I:1     Avg QP:20.06  size: 17848
    x264 [info]: frame P:72    Avg QP:22.12  size:  1337
    x264 [info]: mb I  I16..4: 40.2%  0.0% 59.8%
    x264 [info]: mb P  I16..4:  3.1%  0.0%  2.3%  P16..4:  8.3%  2.0%  0.6%  0.0%  0.0%    skip:83.7%
    x264 [info]: coded y,uvDC,uvAC intra: 53.6% 46.4% 7.4% inter: 3.0% 1.6% 0.0%
    x264 [info]: i16 v,h,dc,p: 11% 65% 12% 12%
    x264 [info]: i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 15% 46% 16%  3%  4%  3%  5%  3%  6%
    x264 [info]: i8c dc,h,v,p: 46% 42% 10%  2%
    x264 [info]: kb/s:312.60

    the last frame number that was encoded is 72 while in VLC stream statistics it shows that 133 frames are Displayed and 66 blocks are decoded for 10 seconds streaming in addition the video playback is bursty.

    my question is how to change the x264 parameters to get 25 FPS ?

  • Video streaming- control frame rate x264

    3 mars 2017, par H.A

    I’m new to video coding, I found this https://github.com/RafaelPalomar/H264LiveStreamer application code very useful to my project. I want to live stream a webcam over RTP . However, I’m having problem selecting the Frame Per Seconds (FPS). below is the function that controls the encoding param.

    void x264Encoder::initilize()
    {
     x264_param_default_preset(&parameters, "veryfast", "zerolatency");
     parameters.i_log_level =  X264_LOG_DEBUG;
     parameters.i_threads = 1;
     parameters.i_width = 640;
     parameters.i_height = 480;
     parameters.i_fps_num = 25;
     parameters.i_fps_den = 1;
     parameters.i_keyint_max = 25;
     parameters.b_intra_refresh = 1;
     parameters.rc.i_rc_method = X264_RC_CRF;
     parameters.rc.i_vbv_buffer_size = 1000000;
     parameters.rc.i_vbv_max_bitrate = 90000;
     parameters.rc.f_rf_constant = 25;
     parameters.rc.f_rf_constant_max = 35;
     parameters.i_sps_id = 7;
     // the following two value you should keep 1
     parameters.b_repeat_headers = 1;    // to get header before every I-Frame
     parameters.b_annexb = 1; // put start code in front of nal. we will remove start code later
     x264_param_apply_profile(&parameters, "baseline");

     encoder = x264_encoder_open(&parameters);
     x264_picture_alloc(&picture_in, X264_CSP_I420, parameters.i_width, parameters.i_height);
     picture_in.i_type = X264_TYPE_AUTO;
     picture_in.img.i_csp = X264_CSP_I420;
     // i have initilized my color space converter for BGR24 to YUV420 because my opencv video capture gives BGR24 image. You can initilize according to your input pixelFormat
     convertContext = sws_getContext(parameters.i_width,parameters.i_height, PIX_FMT_BGR24, parameters.i_width,parameters.i_height,PIX_FMT_YUV420P, SWS_FAST_BILINEAR, NULL, NULL, NULL);
    }

    I’m using VLC as client whatever number i set i_fps_num to, I always get 12-14 FPS. fore example, in VLC Codec tab shows 25 FPS but in Stream statistics tab it shows it only display 13 FPS on average. here is the X264 encoder output

    x264 [debug]: frame=  72 QP=22.24 NAL=2 Slice:P Poc:144 I:97   P:116  SKIP:987  size=1464 bytes
    x264 [info]: frame I:1     Avg QP:20.06  size: 17848
    x264 [info]: frame P:72    Avg QP:22.12  size:  1337
    x264 [info]: mb I  I16..4: 40.2%  0.0% 59.8%
    x264 [info]: mb P  I16..4:  3.1%  0.0%  2.3%  P16..4:  8.3%  2.0%  0.6%  0.0%  0.0%    skip:83.7%
    x264 [info]: coded y,uvDC,uvAC intra: 53.6% 46.4% 7.4% inter: 3.0% 1.6% 0.0%
    x264 [info]: i16 v,h,dc,p: 11% 65% 12% 12%
    x264 [info]: i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 15% 46% 16%  3%  4%  3%  5%  3%  6%
    x264 [info]: i8c dc,h,v,p: 46% 42% 10%  2%
    x264 [info]: kb/s:312.60

    the last frame number that was encoded is 72 while in VLC stream statistics it shows that 133 frames are Displayed and 66 blocks are decoded for 10 seconds streaming in addition the video playback is bursty.

    my question is how to change the x264 parameters to get 25 FPS ?

  • problem in concatenating mass online video urls using ffmpeg [duplicate]

    25 mai 2021, par JohnTerry

    I want to concat n number of videos together using ffmpeg which can also have more than one codec or different resolutions.
I know how to do it with fixed number of videos but input_videos.txt can contain any unknown number of videos. I checked relative posts but they did not have a solution for my problem.

    


    the command i am using for concatenating videos is -

    


    cmd = "ffmpeg -safe 0 -f concat -protocol_whitelist file,http,https,tcp,tls,crypto -segment_time_metadata 1 -i {} -vf select=concatdec_select,scale=1280:720 -af aselect=concatdec_select,aresample=async=1 -c:v libvpx-vp9 -deadline good -cpu-used 5 -c:a libopus {}".format(input_videos.txt, output_video.webm)


    


    Is there a way to achieve the functionality i want ?