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• lavu/cpu : CPU flags for the RISC-V Vector extension

  26 septembre 2022, par Rémi Denis-Courmont

  lavu/cpu : CPU flags for the RISC-V Vector extension
  RVV defines a total of 12 different extensions, including :
   5 different instruction subsets :
  
    - Zve32x : 8-, 16- and 32-bit integers,
  
    - Zve32f : Zve32x plus single precision floats,
  
    - Zve64x : Zve32x plus 64-bit integers,
  
    - Zve64f : Zve32f plus Zve64x,
  
    - Zve64d : Zve64f plus double precision floats.
   6 different vector lengths :
  
    - Zvl32b (embedded only),
  
    - Zvl64b (embedded only),
  
    - Zvl128b,
  
    - Zvl256b,
  
    - Zvl512b,
  
    - Zvl1024b,
   and the V extension proper : equivalent to Zve64f and Zvl128b.
  In total, there are 6 different possible sets of supported instructions
  
  (including the empty set), but for convenience we allocate one bit for
  
  each type sets : up-to-32-bit ints (RVV_I32), floats (RVV_F32),
  
  64-bit ints (RVV_I64) and doubles (RVV_F64).
  Whence the vector size is needed, it can be retrieved by reading the
  
  unprivileged read-only vlenb CSR. This should probably be a separate
  
  helper macro if needed at a later point.
  

  • [DH] libavutil/cpu.c
  • [DH] libavutil/cpu.h
  • [DH] libavutil/riscv/cpu.c
  • [DH] tests/checkasm/checkasm.c

• fluent-ffmpeg wrong output duration

  20 septembre 2022, par Floz42

  I'm trying to stream a video using fluent-ffmpeg and without save it.

  


  I use this code but the output video was cut (12s instead of the 20s of the original video).
I tried many output options but without success.

  


  Precision : I want to get the stream duration in the web player.

  


  Thanks a lot for your help !

  


  

  



  let imageData = [];

let tmp = {};
tmp.filter = 'overlay';
tmp.inputs = '[0:v][1:v]';
tmp.options = {};
//tmp.options.enable = `between(t,${image.startAt}, ${image.endAt})`;
tmp.options.x = imagePositionX;
tmp.options.y = imagePositionY;
tmp.outputs = 'tmp';
imageData.push(tmp);

let size = await ufs(videoURL);

res.status(206);
res.set('Content-Type', 'video/mp4');

if (req.headers.range) {
  let range        = req.headers.range;
  let parts        = range.replace(/bytes=/, "").split("-");
  let partialstart = parts[0];
  let partialend   = parts[1];

  let start     = parseInt(partialstart, 10);
  let end       = partialend ? parseInt(partialend, 10) : size-1;
  let chunksize = (end-start)+1;

  res.set('Content-Range', 'bytes ' + start + '-' + end + '/' + size);
  res.set('Accept-Ranges', 'bytes');
  res.set('Content-Length', chunksize);
} else {
  res.set('Content-Length', size);
}

let stream = ffmpeg(videoURL)
.input(imageURL)
.videoCodec('libx264')
.audioCodec('aac')
.fps('29.97')
.complexFilter(imageData, 'tmp')
.outputOptions([
  '-movflags frag_keyframe+empty_moov',
  '-frag_duration 100',
  '-pix_fmt yuv420p',
  '-map 0:a?',
  '-b:v 2400k',
  '-b:a 160k',
  '-minrate 200k',
  '-maxrate 1300k',
  '-bufsize 13000k',
  '-f mp4',
])
.on('end', () => {
  console.log('file has been converted succesfully');
})
.on('error', (err) => {
  //console.log('error : ', err)
  console.log('error : ', err.message)
})
.pipe(res, {end: true})


  


• libavcodec/libx264 : add user data unregistered SEI encoding

  6 août 2021, par Brad Hards

  libavcodec/libx264 : add user data unregistered SEI encoding
  MISB ST 0604 and ST 2101 require user data unregistered SEI messages
  
  (precision timestamps and sensor identifiers) to be included. That
  
  currently isn't supported for libx264. This patch adds support
  
  for user data unregistered SEI messages in accordance with ISO/IEC
  
  14496-10:2020(E) section D.1.7 (syntax) and D.2.7 (semantics).
  This code is based on a similar change for libx265 (commit
  
  1f58503013720700a5adfd72c708e6275aefc165).
  Signed-off-by : Derek Buitenhuis <derek.buitenhuis@gmail.com>
  

  • [DH] libavcodec/libx264.c