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• avutil/opt : fix mis-alignment of option and constant values for filter help

  13 octobre 2021, par Soft Works

  avutil/opt : fix mis-alignment of option and constant values for filter help
  Before :
  overlay AVOptions :
  
    x                 <string>     ..FV....... set the x expression (default "0")
  
    y                 <string>     ..FV....... set the y expression (default "0")
  
    eof_action        <int>        ..FV....... Action to take when encountering EOF from secondary input  (from 0 to 2) (default repeat)
  
       repeat          0            ..FV....... Repeat the previous frame.
  
       endall          1            ..FV....... End both streams.
  
       pass            2            ..FV....... Pass through the main input.
  
    eval              <int>        ..FV....... specify when to evaluate expressions (from 0 to 1) (default frame)
  After :
  
  a
  
  overlay AVOptions :
  
     x                 <string>     ..FV....... set the x expression (default "0")
  
     y                 <string>     ..FV....... set the y expression (default "0")
  
     eof_action        <int>        ..FV....... Action to take when encountering EOF from secondary input  (from 0 to 2) (default repeat)
  
       repeat          0            ..FV....... Repeat the previous frame.
  
       endall          1            ..FV....... End both streams.
  
       pass            2            ..FV....... Pass through the main input.
  
     eval              <int>        ..FV....... specify when to evaluate expressions (from 0 to 1) (default frame)
  Signed-off-by : softworkz <softworkz@hotmail.com>
  
  Signed-off-by : Marton Balint <cus@passwd.hu>
  

  • [DH] libavutil/opt.c

• avfilter/vf_avgblur : switch to faster algorithm

  24 septembre 2021, par Paul B Mahol

  avfilter/vf_avgblur : switch to faster algorithm
  

  • [DH] libavfilter/vf_avgblur.c
  • [DH] tests/ref/fate/filter-refcmp-psnr-yuv

• FFMPEG error : "First slice in a frame missing" when decoding H.265 stream

  19 octobre 2023, par Snejk

  I have a problem with decoding IP camera stream (h.265) using ffmpeg libraries.

  


  I use Live555 to receive RTP payload.

  


  mMediaSession->readSource()->getNextFrame(mVideoBuffer.data(),
mVideoBuffer.size(), Stream::Static_PayloadRead, this, Stream::Static_StreamClose, this);


  


  First two bytes (after the start code 0001) has the nal_unit_header. I am retrieving the type, from bits 1-6 ( ( NALU[0] >> 1 ) & 0x3F ). Then I am processing the data depending on the NALu type :

  


  enum NalUnitType  
{  
  NAL_UNIT_CODED_SLICE_TRAIL_N = 0,   // 0  
  NAL_UNIT_CODED_SLICE_TRAIL_R,   // 1    
  NAL_UNIT_CODED_SLICE_TSA_N,     // 2  
  NAL_UNIT_CODED_SLICE_TLA,       // 3    
  NAL_UNIT_CODED_SLICE_STSA_N,    // 4  
  NAL_UNIT_CODED_SLICE_STSA_R,    // 5    
  NAL_UNIT_CODED_SLICE_RADL_N,    // 6  
  NAL_UNIT_CODED_SLICE_DLP,       // 7     
  NAL_UNIT_CODED_SLICE_RASL_N,    // 8  
  NAL_UNIT_CODED_SLICE_TFD,       // 9   
  NAL_UNIT_RESERVED_10,  
...
  NAL_UNIT_CODED_SLICE_BLA,       // 16 
  NAL_UNIT_CODED_SLICE_BLANT,     // 17    
  NAL_UNIT_CODED_SLICE_BLA_N_LP,  // 18  
  NAL_UNIT_CODED_SLICE_IDR,       // 19  // Current name in the spec: IDR_W_DLP  
  NAL_UNIT_CODED_SLICE_IDR_N_LP,  // 20  
  NAL_UNIT_CODED_SLICE_CRA,       // 21  
  NAL_UNIT_RESERVED_22,  
 ...
  NAL_UNIT_VPS,                   // 32  
  NAL_UNIT_SPS,                   // 33  
  NAL_UNIT_PPS,                   // 34  
  NAL_UNIT_ACCESS_UNIT_DELIMITER, // 35  
  NAL_UNIT_EOS,                   // 36  
  NAL_UNIT_EOB,                   // 37  
  NAL_UNIT_FILLER_DATA,           // 38  
  NAL_UNIT_SEI,                   // 39 Prefix SEI  
  NAL_UNIT_SEI_SUFFIX,            // 40 Suffix SEI  
...
  NAL_UNIT_INVALID,  
};  


  


  If buffer doesn't have the start code, I am adding 0x00000001 at the start of the payload data, before sending it to FFmpeg. Camera is sending these NALu (in the same order) :

  


  

  1. HEVC_NAL_VPS,

  


  2. HEVC_NAL_SPS,

  


  3. HEVC_NAL_PPS,

  


  4. HEVC_NAL_IDR_W_RADL,

  


  5. HEVC_NAL_IDR_W_RADL,

  


  6. HEVC_NAL_IDR_W_RADL,

  


  7. HEVC_NAL_TRAIL_R,

  


  8. HEVC_NAL_TRAIL_R
...

  


  


  My solution works partially as I have 1/3 of image decoded. The other 2 HEVC_NAL_IDR_W_RADL slices get FFmpeg error : "First slice in a frame missing". If I lower the stream resolution I have 1/2 image with one additional HEVC_NAL_IDR_W_RADL slice.

  


  Similiar code works with H.264 stream so I know (I hope) that Live555 and FFmpeg code should be fine.

  


  Live555 doesn't reassemble the I frames (http://lists.live555.com/pipermail/live-devel/2016-September/020244.html)

  


  Is there a specific way to reassemble frame send in multiple slices. I have even tried to assemble the frame as it would be Fragmented Unit NAL type 49 (How to depacketize the fragmented frames in RTP data (over UDP) for H265/HEVC ?)

  


  Many Thanks