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• Merge commit 'cd4663dc80323ba64989d0c103d51ad3ee0e9c2f'

  12 novembre 2017, par James Almer

  Merge commit 'cd4663dc80323ba64989d0c103d51ad3ee0e9c2f'
  * commit 'cd4663dc80323ba64989d0c103d51ad3ee0e9c2f' :
  
    smacker : add sanity check for length in smacker_decode_tree()
  See b829da363985cb2f80130bba304cc29a632f6446
  Merged-by : James Almer <jamrial@gmail.com>
  

  • [DH] libavcodec/smacker.c

• tf.contrib.signal.stft returns an empty matrix

  9 décembre 2017, par matt-pielat

  This is the piece of code I run :

  import tensorflow as tf
  
  
  
  sess = tf.InteractiveSession()
  
  
  
  filename = 'song.mp3' # 30 second mp3 file
  
  SAMPLES_PER_SEC = 44100
  
  
  
  audio_binary = tf.read_file(filename)
  
  
  
  pcm = tf.contrib.ffmpeg.decode_audio(audio_binary, file_format='mp3', samples_per_second=SAMPLES_PER_SEC, channel_count = 1)
  
  stft = tf.contrib.signal.stft(pcm, frame_length=1024, frame_step=512, fft_length=1024)
  
  
  
  sess.close()

  The mp3 file is properly decoded because print(pcm.eval().shape) returns :

  (1323119, 1)

  And there are even some actual non-zero values when I print them with print(pcm.eval()[1000:1010]) :

  [[ 0.18793298]
  
   [ 0.16214484]
  
   [ 0.16022217]
  
   [ 0.15918455]
  
   [ 0.16428113]
  
   [ 0.19858395]
  
   [ 0.22861415]
  
   [ 0.2347789 ]
  
   [ 0.22684409]
  
   [ 0.20728172]]

  But for some reason print(stft.eval().shape) evaluates to :

  (1323119, 0, 513) # why the zero dimension?

  And therefore print(stft.eval()) is :

  []

  According to this the second dimension of the tf.contrib.signal.stft output is equal to the number of frames. Why are there no frames though ?

• Using ffmpeg to generate dash manifest and it cannot be played by dash.js

  18 mars 2019, par Punkhead

  I’m using ffmpeg to encode incoming stream via rtmp protocol, the code as following :

  ffmpeg -re -i rtmp://localhost:1935${StreamPath} -use_timeline 1 /
  
  -use_template 1 -window_size 10 -min_seg_duration 5000 -f dash out.mpd

  The manifest looks like this :

  <?xml version="1.0" encoding="utf-8"?>
  
  <mpd xmlns="urn:mpeg:dash:schema:mpd:2011" profiles="urn:mpeg:dash:profile:isoff-live:2011" type="static" mediapresentationduration="PT1M36.4S" minbuffertime="PT8.3S">
  
      <programinformation>
  
      </programinformation>
  
      <period start="PT0.0S">
  
          <adaptationset contenttype="video" segmentalignment="true" bitstreamswitching="true" framerate="30/1">
  
          <representation mimetype="video/mp4" codecs="avc1.640028" width="1920" height="1080" framerate="30/1">
  
              <segmenttemplate timescale="15360" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="4">
  
                  <segmenttimeline>
  
                      <s t="384000" d="128000"></s>
  
                      <s d="71680"></s>
  
                      <s d="128000" r="4"></s>
  
                      <s d="56832"></s>
  
                      <s d="128000"></s>
  
                      <s d="72704"></s>
  
                  </segmenttimeline>
  
              </segmenttemplate>
  
          </representation>
  
      </adaptationset>
  
      <adaptationset contenttype="audio" segmentalignment="true" bitstreamswitching="true">
  
          <representation mimetype="audio/mp4" codecs="mp4a.40.2" bandwidth="128000" audiosamplingrate="44100">
  
              <audiochannelconfiguration schemeiduri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"></audiochannelconfiguration>
  
              <segmenttemplate timescale="44100" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="4">
  
                  <segmenttimeline>
  
                      <s t="1099755" d="367616"></s>
  
                      <s d="205824"></s>
  
                      <s d="367616" r="4"></s>
  
                      <s d="162816"></s>
  
                      <s d="367616"></s>
  
                      <s d="207872"></s>
  
                  </segmenttimeline>
  
              </segmenttemplate>
  
          </representation>
  
      </adaptationset>
  
  </period>
  
  </mpd>

  When I try to play it on dash.js player, a error occured :

  [112] Parsing complete: ( xml2json: 3.50ms, objectiron: 1.76ms, total: 0.00526s) Debug.js:127 
  
  [116] SegmentTimeline detected using calculated Live Edge Time Debug.js:127 
  
  [118] MediaSource attached to element.  Waiting on open... Debug.js:127 
  
  [119] Manifest has been refreshed at Tue Jan 02 2018 01:57:35 GMT+0800 [1514829455.1] Debug.js:127 
  
  [155] MediaSource is open! Debug.js:127 
  
  [156] Duration successfully set to: 96.4 Debug.js:127 
  
  [157] Added 0 inline events Debug.js:127 
  
  [158] video codec: video/mp4;codecs="avc1.640028" Stream.js:225 
  
  Uncaught TypeError: Cannot read property 'type' of null
  
      at z (Stream.js:225)
  
      at C (Stream.js:285)
  
      at D (Stream.js:373)
  
      at E (Stream.js:398)
  
      at Object.d [as activate] (Stream.js:107)
  
      at y (StreamController.js:363)
  
      at MediaSource.c (StreamController.js:342)

  then it fails to playback...

  Is it because I didn’t set the parameters right on ffmpeg or this is a bug in dash.js ?

  I really stuck here !