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• How to open a HEIF (.heic) image ?

  14 décembre 2022, par Jean-Milost Reymond

  For a c++ project, I need to open and show a HEIF (.heic) image. What I know (if I'm right) is that the HEIF images are based on the ffmpeg standard, and requires a H265 codec to be read.

  



  I found several open-source H265 codecs :

  



  

  • OpenHEVC (https://github.com/OpenHEVC/openHEVC)

  


  • x265 (https://bitbucket.org/multicoreware/x265/downloads/)

  


  • libde265 (https://github.com/strukturag/libde265)

  


  



  I can open and show H265 encoded video files with each of them, but I'm unable to simply open, show or convert a .heic image. All of them return an error, or just do nothing.

  



  To be honest I'm a little puzzled, because the HEIF standard seem to be a well kept secret. I'm unable to find a relevant info that could allow me to walk to a solution. Those I found are just tricks and workarounds, like e.g. forcing the device (I'm speaking here about the Apple iPhone using the new iOS11) to generate a jpg image instead of a heic, or using a third party application like dr.fone. Of course these solutions are irrelevant for me.

  



  So, somebody can tell me which codec I should use with a .heif image, and how I can use it to open it ? Or are there open source libraries or examples that allow to manipulate this type of image file ? Somebody can point me to the good direction ?

  


• Can anyone help me with the errors ?

  11 juillet 2017, par joel

  I am a newbie to ffmpeg module. Here is my code to read audio wave files using ffmpeg and pipe.

   import numpy as np
  
   import subprocess as sp
  
   import os
  
   from os.path import join
  
   from multiprocessing import Pool
  
   smpler=44100
  
   files= list()
  
  
  
  
  
   for roots, dirs, filek in os.walk("/home/joel/pymusic/mu2"):
  
      for fi in filek:
  
        files.append(os.path.join("/home/joel/pymusic/mu2",fi))
  
  
  
  
  
  def load(filename,in_typ=np.int16,out_typ=np.float32):
  
     channels=1
  
     form={
  
     np.int16:'s16le'
  
       }
  
     f_s= form[in_typ]
  
     command=[
  
       'ffmpeg',
  
       '-i',filename,
  
       '-f',f_s,
  
       '-acodec', 'pcm_' + f_s,
  
       '-ar', str(smpler),
  
       '-ac',str(channels),'-']
  
     raw=b' '
  
     pi=sp.Popen(command, stdout=sp.PIPE, bufsize=4096)
  
     read_c= smpler*channels*16
  
     while True:
  
      data= pi.stdout.read(read_c )
  
      if data:
  
          raw += data
  
      else:
  
          break
  
     audio= np.fromstring(raw, dtype=np.int16).astype(np.float32)
  
     return audio
  
  def helper(f):
  
        return(load(f))
  
  p= Pool()
  
  array= p.map(helper, files)
  
  p.close()
  
  p.join()

  Where files is a list consisting of 20 audio wave files.
  I’m getting the error as :

  >File "prj2.py", line 42, in <module>
  
  >      array= p.map(helper, files)
  
  >File "/usr/lib/python2.7/multiprocessing/pool.py", line 251, in map
  
  >     return self.map_async(func, iterable, chunksize).get()
  
  >File "/usr/lib/python2.7/multiprocessing/pool.py", line 558, in get
  
  >     raise self._value
  
  >ValueError: string size must be a multiple of element size
  
  </module>

  Can anyone help me out with these errors ?

• FFMpeg batch convert video files hangs

  13 juin 2017, par Benson Chang

  I have some .avi file contains video encoded in h264, and I would like to change to .mp4 and change the rates if needed. You can see the code used to convert below. My problem is that ffmpeg will hang when I try to convert all files, and the file it hangs changes from time to time, I wonder why ? Below the code is the output where ffmpeg hangs. I’m running under windows 10, python 2.7.

  import subprocess
  
  import os
  
  
  
  def convert(fileName):
  
      sourceFile = fileName
  
      print sourceFile.split('.')
  
      targetFile = fileName.split('.')[0] + ".mp4"
  
      subprocess.call(['ffmpeg', '-y', '-i', sourceFile, '-r',
  
           '30000/1001', '-b:a', '2M', '-bt', '4M', '-vcodec',
  
            'libx264', '-pass', '1', '-coder', '0', '-bf', '0',
  
             '-flags', '-loop', '-wpredp', '0', '-an', targetFile])
  
  
  
  
  
  
  
  # Set the directory you want to start from
  
  def convertBatch(rootDir = '.'):
  
      for dirName, subdirList, fileList in os.walk(rootDir):
  
          print('Found directory: %s' % dirName)
  
  
  
          for fname in fileList:
  
              if fname.endswith(".avi"):
  
                  convert('%s/%s' % (dirName,fname))
  
                  #os.remove('%s/%s' % (dirName,fname))
  
  
  
  
  
  convertBatch("F:\\data\\mp4")

  ---

  ffmpeg version 3.1.4 Copyright (c) 2000-2016 the FFmpeg developers
  
    built with gcc 5.4.0 (GCC)
  
    configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --enable-bzlib --enable-libebur128 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-lzma --enable-decklink --enable-zlib
  
    libavutil      55. 28.100 / 55. 28.100
  
    libavcodec     57. 48.101 / 57. 48.101
  
    libavformat    57. 41.100 / 57. 41.100
  
    libavdevice    57.  0.101 / 57.  0.101
  
    libavfilter     6. 47.100 /  6. 47.100
  
    libswscale      4.  1.100 /  4.  1.100
  
    libswresample   2.  1.100 /  2.  1.100
  
    libpostproc    54.  0.100 / 54.  0.100
  
  Input #0, avi, from 'filename.avi':
  
    Metadata:
  
      encoder         : Lavf57.56.100
  
    Duration: 00:00:01.00, start: 0.000000, bitrate: 611 kb/s
  
      Stream #0:0: Video: h264 (Constrained Baseline) (x264 / 0x34363278), yuv420p, 1024x1024, 578 kb/s, 30 fps, 30 tbr, 30 tbn, 60 tbc
  
  Codec AVOption b (set bitrate (in bits/s)) specified for output file #0 (F:\data\mp4_1_16\11\14\512/11_14_512_16.mp4) has not been used for any stream. The most likely reason is either wrong type (e.g. a video option with no video streams) or that it is a private option of some encoder which was not actually used for any stream.
  
  [libx264 @ 00000000028e42c0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
  
  [libx264 @ 00000000028e42c0] profile Constrained Baseline, level 3.2
  
  [libx264 @ 00000000028e42c0] 264 - core 148 r2721 72d53ab - H.264/MPEG-4 AVC codec - Copyleft 2003-2016 - http://www.videolan.org/x264.html - options: cabac=0 ref=1 deblock=1:0:0 analyse=0x1:0 me=dia subme=2 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=18 lookahead_threads=6 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
  
  [mp4 @ 0000000002bd00a0] Using AVStream.codec to pass codec parameters to muxers is deprecated, use AVStream.codecpar instead.
  
  Output #0, mp4, to 'filename.mp4':
  
    Metadata:
  
      encoder         : Lavf57.41.100
  
      Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1024x1024, q=-1--1, 29.97 fps, 30k tbn, 29.97 tbc
  
      Metadata:
  
        encoder         : Lavc57.48.101 libx264
  
      Side data:
  
        cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
  
  Press [q] to stop, [?] for help