Recherche avancée

Sur d’autres sites (13557)

• How can I stream very long H.264 videos over HTTP without long startup times ? (or : MOOV atom too large)

  5 octobre 2012, par michael

  I want to stream videos of public meetings that are often 10 hours long. Users will generally be starting at some point in the middle of the video and jumping around frequently.

  H.264 in an MP4 container seems like the current best option for encoding streaming video (right ?). But these are large files — about 1.3GB for one file — and the metadata (MOOV atom) at the beginning of the file is itself about 40MB. If I understand correctly, clients need to download the full metadata before they're able to seek within the remainder of the file. Obviously, having to download 40MB before you can start streaming is unacceptable.

  (My tests of streaming have been with VLC and the HTML5 tag in Chrome.)

  I'm encoding the file using avconv, and am currently providing no additional settings beyond telling it which encoders to use (x264 and libfaac). I then move the metadata to the beginning of the file using qt-faststart.

  Is there a way to make the MOOV atom smaller ?

  If not, are there other strategies to use (e.g. is splitting long videos into several files something that's frequently done ? it seems like a real pain in terms of users seeking around the whole day's video) ?

  Or should I be using a different codec or container ?

  thanks !

  Here's a breakdown of the file header structure, from AtomicParsley :

  Atom ftyp @ 0 of size: 32, ends @ 32
  
  Atom moov @ 32 of size: 40157673, ends @ 40157705
  
       Atom mvhd @ 40 of size: 108, ends @ 148
  
       Atom iods @ 148 of size: 24, ends @ 172
  
       Atom trak @ 172 of size: 20156304, ends @ 20156476
  
           Atom tkhd @ 180 of size: 92, ends @ 272
  
           Atom edts @ 272 of size: 36, ends @ 308
  
               Atom elst @ 280 of size: 28, ends @ 308
  
           Atom mdia @ 308 of size: 20156168, ends @ 20156476
  
               Atom mdhd @ 316 of size: 32, ends @ 348
  
               Atom hdlr @ 348 of size: 45, ends @ 393
  
               Atom minf @ 393 of size: 20156083, ends @ 20156476
  
                   Atom vmhd @ 401 of size: 20, ends @ 421
  
                   Atom dinf @ 421 of size: 36, ends @ 457
  
                       Atom dref @ 429 of size: 28, ends @ 457
  
                   Atom stbl @ 457 of size: 20156019, ends @ 20156476
  
                       Atom stsd @ 465 of size: 147, ends @ 612
  
                           Atom avc1 @ 481 of size: 131, ends @ 612
  
                               Atom avcC @ 567 of size: 45, ends @ 612
  
                       Atom stts @ 612 of size: 6115608, ends @ 6116220
  
                       Atom stss @ 6116220 of size: 16960, ends @ 6133180
  
                       Atom ctts @ 6133180 of size: 5683824, ends @ 11817004
  
                       Atom stsc @ 11817004 of size: 28, ends @ 11817032
  
                       Atom stsz @ 11817032 of size: 4169724, ends @ 15986756
  
                       Atom stco @ 15986756 of size: 4169720, ends @ 20156476
  
       Atom trak @ 20156476 of size: 20001133, ends @ 40157609
  
           Atom tkhd @ 20156484 of size: 92, ends @ 20156576
  
           Atom mdia @ 20156576 of size: 20001033, ends @ 40157609
  
               Atom mdhd @ 20156584 of size: 32, ends @ 20156616
  
               Atom hdlr @ 20156616 of size: 45, ends @ 20156661
  
               Atom minf @ 20156661 of size: 20000948, ends @ 40157609
  
                   Atom smhd @ 20156669 of size: 16, ends @ 20156685
  
                   Atom dinf @ 20156685 of size: 36, ends @ 20156721
  
                       Atom dref @ 20156693 of size: 28, ends @ 20156721
  
                   Atom stbl @ 20156721 of size: 20000888, ends @ 40157609
  
                       Atom stsd @ 20156729 of size: 96, ends @ 20156825
  
                           Atom mp4a @ 20156745 of size: 80, ends @ 20156825
  
                               Atom esds @ 20156781 of size: 44, ends @ 20156825
  
                       Atom stts @ 20156825 of size: 9348168, ends @ 29504993
  
                       Atom stsc @ 29504993 of size: 28, ends @ 29505021
  
                       Atom stsz @ 29505021 of size: 5326296, ends @ 34831317
  
                       Atom stco @ 34831317 of size: 5326292, ends @ 40157609
  
       Atom udta @ 40157609 of size: 96, ends @ 40157705
  
           Atom meta @ 40157617 of size: 88, ends @ 40157705
  
               Atom hdlr @ 40157629 of size: 33, ends @ 40157662
  
               Atom ilst @ 40157662 of size: 43, ends @ 40157705
  
                   Atom ©too @ 40157670 of size: 35, ends @ 40157705
  
                       Atom data @ 40157678 of size: 27, ends @ 40157705
  
  Atom free @ 40157705 of size: 8, ends @ 40157713
  
  Atom mdat @ 40157713 of size: 1320096566, ends @ 1360254279

• Error with LocalAudioFile(file) returns OSError : [Errno 2] No such file or directory

  5 mars 2016, par beriukay

  Much like the question here http://developer.echonest.com/forums/thread/3843#reply, I am having the following error :

  File
  "/usr/local/lib/python2.7/dist-packages/echonest/remix/audio.py", line
  944, in init
  sampleRate=sampleRate, numChannels=numChannels) File "/usr/local/lib/python2.7/dist-packages/echonest/remix/audio.py", line
  403, in init
  self.load() File "/usr/local/lib/python2.7/dist-packages/echonest/remix/audio.py", line
  421, in load
  numChannels=self.numChannels, sampleRate=self.sampleRate, verbose=self.verbose) File
  "/usr/local/lib/python2.7/dist-packages/echonest/remix/support/ffmpeg.py",
  line 91, in ffmpeg
  close_fds=(not win) File "/usr/lib/python2.7/subprocess.py", line 710, in init
  errread, errwrite) File "/usr/lib/python2.7/subprocess.py", line 1327, in _execute_child
  raise child_exception OSError : [Errno 2] No such file or directory

  I checked input and output file permissions, made sure that both files and all related file paths existed, and that I have all the relevant python tools installed. The first clue is that Subprocess.py is having trouble. Looking at ffmpeg.py on line 88, I started playing around with the Popen function call to see how and why it was misbehaving.

  Solution :

  After messing around with the ffmpeg.py file, I piped the input to the shell (shell=True instead of shell=False), which raised the following error :

  check raise Run timeError(ffmpeg_install_instructions) RuntimeError: en-ffmpeg not found! Please make sure ffmpeg is installed and create a link as follows: sudo ln -s which ffmpeg /usr/local/bin/en-ffmpeg Alternatively, import echonest.remix.support.ffmpeg and modify ffmpeg.FFMPEG to name the appropriate binary.

  So, to finalize the solution, you need to get the binary from https://ffmpeg.org/download.html#build-linux, which in Ubuntu 14.04 means you just need to :

  sudo add-apt-repository ppa:mc3man/trusty-media
  
  sudo apt-get update && sudo apt-get upgrade
  
  sudo apt-get install ffmpeg
  
  sudo ln -s `which ffmpeg` /usr/local/bin/en-ffmpeg

  That should clear this problem right up.

• Google Speech API returns empty result for some FLAC files, and not for the others although they have same codec and sample rate

  15 mars 2021, par Chad

  Below code is what I used to make request for transcription.

  


  import io
from google.cloud import speech_v1p1beta1 as speech
def transcribe_file(speech_file):
    """Transcribe the given audio file."""

    client = speech.SpeechClient()

    encoding = speech.RecognitionConfig.AudioEncoding.FLAC
    if os.path.splitext(speech_file)[1] == ".wav":
        encoding = speech.RecognitionConfig.AudioEncoding.LINEAR16
    with io.open(speech_file, "rb") as audio_file:
        content = audio_file.read()

    audio = speech.RecognitionAudio(content=content)
    config = speech.RecognitionConfig(
        encoding=speech.RecognitionConfig.AudioEncoding.FLAC,
        sample_rate_hertz=32000,
        language_code="ja-JP",
        max_alternatives=3,
        enable_word_time_offsets=True,
        enable_automatic_punctuation=True,
        enable_word_confidence=True,
    )

    response = client.recognize(config=config, audio=audio)
    #print(speech_file, "Recognition Done")
    return response


  


  As I wrote in title, the results of response has empty list for some files, and not for some files.
They have same sample rate and codec(32000, FLAC)

  


  Below is the result of ffprobe -i "AUDIOFILE" -show_streams for one of each cases.

  


  Left one is empty one. The only difference is duration of file.

  


  How can I get non empty results ?

  


  Result of ffprobe

  


  Edit :

  


  Result of ffprobe show stream show format

  


  Something not captured in one screen

  


  Sadly, re-mux didn't work.

  


  I used ffmpeg-git-20210225

  


  ffbrobe result of broken one

  


  ./ffprobe -show_streams -show_format broken.flac 
ffprobe version N-56320-ge937457b7b-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2007-2021 the FFmpeg developers
  built with gcc 8 (Debian 8.3.0-6)
  configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-libgme --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
  libavutil      56. 66.100 / 56. 66.100
  libavcodec     58.125.101 / 58.125.101
  libavformat    58. 68.100 / 58. 68.100
  libavdevice    58. 12.100 / 58. 12.100
  libavfilter     7.107.100 /  7.107.100
  libswscale      5.  8.100 /  5.  8.100
  libswresample   3.  8.100 /  3.  8.100
  libpostproc    55.  8.100 / 55.  8.100
Input #0, flac, from 'broken.flac':
  Metadata:
    encoder         : Lavf58.45.100
  Duration: 00:00:00.90, start: 0.000000, bitrate: 342 kb/s
  Stream #0:0: Audio: flac, 32000 Hz, mono, s16
[STREAM]
index=0
codec_name=flac
codec_long_name=FLAC (Free Lossless Audio Codec)
profile=unknown
codec_type=audio
codec_tag_string=[0][0][0][0]
codec_tag=0x0000
sample_fmt=s16
sample_rate=32000
channels=1
channel_layout=mono
bits_per_sample=0
id=N/A
r_frame_rate=0/0
avg_frame_rate=0/0
time_base=1/32000
start_pts=0
start_time=0.000000
duration_ts=28672
duration=0.896000
bit_rate=N/A
max_bit_rate=N/A
bits_per_raw_sample=16
nb_frames=N/A
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=0
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
DISPOSITION:timed_thumbnails=0
[/STREAM]
[FORMAT]
filename=broken.flac
nb_streams=1
nb_programs=0
format_name=flac
format_long_name=raw FLAC
start_time=0.000000
duration=0.896000
size=38362
bit_rate=342517
probe_score=100
TAG:encoder=Lavf58.45.100
[/FORMAT]


  


  ffprobe result of non_broken one

  


  ./ffprobe -show_streams -show_format non_broken.flac 
ffprobe version N-56320-ge937457b7b-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2007-2021 the FFmpeg developers
  built with gcc 8 (Debian 8.3.0-6)
  configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-libgme --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
  libavutil      56. 66.100 / 56. 66.100
  libavcodec     58.125.101 / 58.125.101
  libavformat    58. 68.100 / 58. 68.100
  libavdevice    58. 12.100 / 58. 12.100
  libavfilter     7.107.100 /  7.107.100
  libswscale      5.  8.100 /  5.  8.100
  libswresample   3.  8.100 /  3.  8.100
  libpostproc    55.  8.100 / 55.  8.100
Input #0, flac, from 'non_broken.flac':
  Metadata:
    encoder         : Lavf58.45.100
  Duration: 00:00:00.86, start: 0.000000, bitrate: 358 kb/s
  Stream #0:0: Audio: flac, 32000 Hz, mono, s16
[STREAM]
index=0
codec_name=flac
codec_long_name=FLAC (Free Lossless Audio Codec)
profile=unknown
codec_type=audio
codec_tag_string=[0][0][0][0]
codec_tag=0x0000
sample_fmt=s16
sample_rate=32000
channels=1
channel_layout=mono
bits_per_sample=0
id=N/A
r_frame_rate=0/0
avg_frame_rate=0/0
time_base=1/32000
start_pts=0
start_time=0.000000
duration_ts=27648
duration=0.864000
bit_rate=N/A
max_bit_rate=N/A
bits_per_raw_sample=16
nb_frames=N/A
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=0
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
DISPOSITION:timed_thumbnails=0
[/STREAM]
[FORMAT]
filename=non_broken.flac
nb_streams=1
nb_programs=0
format_name=flac
format_long_name=raw FLAC
start_time=0.000000
duration=0.864000
size=38701
bit_rate=358342
probe_score=100
TAG:encoder=Lavf58.45.100
[/FORMAT]


  


  And the result of ffmpeg -f lavfi -i sine=d=0.864:r=32000 output.flac

  


  ffmpeg version 3.4.8-0ubuntu0.2 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 7 (Ubuntu 7.5.0-3ubuntu1~18.04)
  configuration: --prefix=/usr --extra-version=0ubuntu0.2 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
  WARNING: library configuration mismatch
  avcodec     configuration: --prefix=/usr --extra-version=0ubuntu0.2 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared --enable-version3 --disable-doc --disable-programs --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libtesseract --enable-libvo_amrwbenc
  libavutil      55. 78.100 / 55. 78.100
  libavcodec     57.107.100 / 57.107.100
  libavformat    57. 83.100 / 57. 83.100
  libavdevice    57. 10.100 / 57. 10.100
  libavfilter     6.107.100 /  6.107.100
  libavresample   3.  7.  0 /  3.  7.  0
  libswscale      4.  8.100 /  4.  8.100
  libswresample   2.  9.100 /  2.  9.100
  libpostproc    54.  7.100 / 54.  7.100
Input #0, lavfi, from 'sine=d=0.864:r=32000':
  Duration: N/A, start: 0.000000, bitrate: 512 kb/s
    Stream #0:0: Audio: pcm_s16le, 32000 Hz, mono, s16, 512 kb/s
File 'output.flac' already exists. Overwrite ? [y/N] y
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le (native) -> flac (native))
Press [q] to stop, [?] for help
Output #0, flac, to 'output.flac':
  Metadata:
    encoder         : Lavf57.83.100
    Stream #0:0: Audio: flac, 32000 Hz, mono, s16, 128 kb/s
    Metadata:
      encoder         : Lavc57.107.100 flac
[Parsed_sine_0 @ 0x55c317ddda00] EOF timestamp not reliable
size=      16kB time=00:00:00.86 bitrate= 154.0kbits/s speed= 205x    
video:0kB audio:8kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 99.364586%