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• Video got chopped down from starting

  21 juillet 2016, par Nayan Katkani

  I am using FFMPEG encoder to upload a video from my application at youtube every thing works fine but the video get chopped down from starting. For example video will start at a delay of 30 second.

  My internet downloading speed is 18 Mbps and uploading speed is 14 Mbps.

  Parameters which I used are as follows :

    _processArgs = new Vector.<string>();
  
  
  
    _processArgs.push('-re');
  
    _processArgs.push('-i');// input flag
  
    _processArgs.push(videoPath);
  
    _processArgs.push('-codec:a');//audio encoding
  
    _processArgs.push('copy');
  
    _processArgs.push('-codec:v');// video encoding
  
    _processArgs.push('copy');
  
    _processArgs.push('-maxrate'); // bitrate:audio flag
  
    _processArgs.push('9000k');
  
    _processArgs.push('-bufsize');
  
    _processArgs.push('18000k');
  
    _processArgs.push('-pix_fmt'); //set the pixel format 
  
    _processArgs.push('yuv422p');
  
    _processArgs.push('-preset');//  encoding
  
    _processArgs.push('faster');
  
    _processArgs.push('-ac'); //set the no. of audio channel
  
    _processArgs.push('2');
  
    _processArgs.push('-r'); //set the frame rate
  
    _processArgs.push('24');
  
    _processArgs.push('-g');// GOP size
  
    _processArgs.push('60');
  
    _processArgs.push('-ar');//sampling frequency
  
    _processArgs.push('44100');
  
    _processArgs.push('-f');
  
    _processArgs.push('flv');//deliver the output stream in an flv wrapper
  
    _processArgs.push(streamurl+'/'+streamname);
  
  
  
    nativeProcessStartupInfo.arguments = processArgs;
  
  </string>

  Also, I am uploading video of resolution of "2560 x 1440" pixels

  Thanks

• avutil/mips : refactor msa load and store macros.

  17 juillet 2019, par Shiyou Yin

  avutil/mips : refactor msa load and store macros.
  Replace STnxm_UB and LDnxm_SH with new macros ST_H/W/D1/2/4/8.
  
  The old macros are difficult to use because they don't follow the same parameter passing rules.
  
  Changing details as following :
  
  1. remove LD4x4_SH.
  
  2. replace ST2x4_UB with ST_H4.
  
  3. replace ST4x2_UB with ST_W2.
  
  4. replace ST4x4_UB with ST_W4.
  
  5. replace ST4x8_UB with ST_W8.
  
  6. replace ST6x4_UB with ST_W2 and ST_H2.
  
  7. replace ST8x1_UB with ST_D1.
  
  8. replace ST8x2_UB with ST_D2.
  
  9. replace ST8x4_UB with ST_D4.
  
  10. replace ST8x8_UB with ST_D8.
  
  11. replace ST12x4_UB with ST_D4 and ST_W4.
  Examples of new macro : ST_H4(in, idx0, idx1, idx2, idx3, pdst, stride)
  
  ST_H4 store four half-word elements in vector 'in' to pdst with stride.
  
  About the macro name :
  
  1) 'ST' means store operation.
  
  2) 'H/W/D' means type of vector element is 'half-word/word/double-word'.
  
  3) Number '1/2/4/8' means how many elements will be stored.
  
  About the macro parameter :
  
  1) 'in0, in1...' 128-bits vector.
  
  2) 'idx0, idx1...' elements index.
  
  3) 'pdst' destination pointer to store to
  
  4) 'stride' stride of each store operation.
  Signed-off-by : Michael Niedermayer <michael@niedermayer.cc>
  

  • [DH] libavcodec/mips/h263dsp_msa.c
  • [DH] libavcodec/mips/h264chroma_msa.c
  • [DH] libavcodec/mips/h264dsp_msa.c
  • [DH] libavcodec/mips/h264idct_msa.c
  • [DH] libavcodec/mips/h264qpel_msa.c
  • [DH] libavcodec/mips/hevc_idct_msa.c
  • [DH] libavcodec/mips/hevc_lpf_sao_msa.c
  • [DH] libavcodec/mips/hevc_mc_bi_msa.c
  • [DH] libavcodec/mips/hevc_mc_biw_msa.c
  • [DH] libavcodec/mips/hevc_mc_uni_msa.c
  • [DH] libavcodec/mips/hevc_mc_uniw_msa.c
  • [DH] libavcodec/mips/hevcdsp_msa.c
  • [DH] libavcodec/mips/hevcpred_msa.c
  • [DH] libavcodec/mips/hpeldsp_msa.c
  • [DH] libavcodec/mips/qpeldsp_msa.c
  • [DH] libavcodec/mips/vp3dsp_idct_msa.c
  • [DH] libavcodec/mips/vp8_idct_msa.c
  • [DH] libavcodec/mips/vp8_lpf_msa.c
  • [DH] libavcodec/mips/vp8_mc_msa.c
  • [DH] libavcodec/mips/vp9_idct_msa.c
  • [DH] libavcodec/mips/vp9_intra_msa.c
  • [DH] libavcodec/mips/vp9_lpf_msa.c
  • [DH] libavcodec/mips/vp9_mc_msa.c
  • [DH] libavutil/mips/generic_macros_msa.h

• VBV-CBR and ABR in X264

  11 décembre 2013, par xkfz007

  In x264 VBV-CBR RC mode is based on ABR and vbv-maxrate and vbv-bufsize are set. On the basis of frame QP decided by ABR, the MB row QP is decided by VBV-CBR for each row. I test these two modes and the command lines are listed :
  ABR : -o BasketballDrill_832x480_50_20131210102507.264 BasketballDrill_832x480_50.yuv 832x480 —fps 50 —frames 300 —bitrate 1120 —profile baseline —threads -1 -I 50 -v —psnr
  VBV-CBR : -o BasketballDrill_832x480_50_20131210102507_mb.264 BasketballDrill_832x480_50.yuv 832x480 —fps 50 —frames 300 —bitrate 1120 —vbv-maxrate 1120 —vbv-bufsize 1680 —profile baseline —threads 1 -I 50 -v —psnr

  The final results are :
  ABR : Y-PSNR 31.530dB, bitrate 1146.93kbps
  VBV-CBR : Y-PSNR 31.728dB, bitrate 1230.25kbps
  Compared to ABR, VBV-CBR achieved 4.9% bitrate promotion and 0.198dB PSNR promotion. But the PSNR promotion is lower than bitrate (1% bitrate=0.05dB).

  Having talked so much, I just want to ask what is the advantage of VBV-CBR compared ABR ? If ABR can get the reasonable results, why the VBV-cBR is needed ?
  In my opinion, VBV-CBR maybe can promote the subjective quality owing to deciding the QP for each MB row. But the bitrate also rises. Also I have compared some frames of the two modes, they are almost the same.
  Maybe there are some situations that are fit for VBV-CBR and I don't know. So guys, give me, the new to x264, some professional explanation.