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• Diamond Rio Artifacts

  30 août 2012, par Multimedia Mike — Multimedia History

  Remember the Diamond Rio PMP300 ? It’s credited with being the very first portable MP3 player, released all the way back in 1998 (I say ‘credited’ because I visited an audio museum once which exhibited a Toshiba MP3 player from 1997). I recently rescued a pristine set of Rio artifacts from a recycle pile.

  
  
  

  I wondered if I should scan the manual for posterity. However, a Google search indicates that a proper PDF (loaded with pleas to not illegally copy music) isn’t very difficult to come by. Here are the other items that came with the unit :

  
  
  Click for larger image
  

  Ah, more memories (of dialup internet) : A tie-in with another Diamond product, this time a modem which claims to enable the user to download songs at up to 112 kilobits per second. I wonder if that was really possible. I remember that 56k modems were a stretch and 33.6k was the best that most users could hope for.

  There is also a separate piece of paper that advises the buyer that the parallel port adapter might look a bit different than what is seen in the printed copy. Imagine the age of downloading to your MP3 player via parallel port while pulling down new songs via dialup internet.

  The artifacts also included not one, but two CD-ROMs :

  
  
  Click for larger image
  

  One is a driver and software disc, so no big surprise there. The other has a selection of MP3 files for your shiny new MP3 player. I’m wondering if these should be proactively preserved. I was going to process the files’ metadata and publish it here, for the benefit of search engines. However, while metadata is present, the files don’t conform to any metadata format that FFmpeg/Libav recognize. The files mention Brava Software Inc. in their metadata sections. Still, individual filenames at the end of this post.

  Leftovers :
  A few other miscellaneous multimedia acquisitions :

  
  
  

  I still want to study all of these old multimedia creation programs in depth some day. Theatrix Hollywood is a creative writing game, Wikipedia alleges (I’m a bit rigid with my exact definition of what constitutes a game). Here is an example movie output from this software. Meanwhile, the Mad Dog Multimedia CD-ROM apparently came packaged with a 56X CD-ROM drive (roughly the pinnacle of CD-ROM speeds). I found it has some version of Sonic Foundry’s ACID software, thus making good on the “applications” claim on the CD-ROM copy.

  Diamond Rio MP3 Sampler
  These are the names of the MP3 files found on the Diamond Rio MP3 sampler for the benefit of search engines.

  13_days.mp3
  albert_einstein_dreams.mp3
  a_man_of_many_colours.mp3
  anything_for_love.mp3
  a_secret_place.mp3
  bake_sale.mp3
  bigger_than_the_both_of_us.mp3
  boogie_beat.mp3
  bring_it_on.mp3
  buskersoundcheck_hippo.mp3
  charm.mp3
  chemical_disturbance.mp3
  coastin.mp3
  credit_is_due.mp3
  dance_again.mp3
  destiny.mp3
  dig_a_little_deeper.mp3
  diplomat6_bigmouthshut.mp3
  dirty_littlemonster.mp3
  dirty.mp3
  drivin.mp3
  Eric_Clapton_Last_Train.mp3
  etude_in_c_sharp_minor_op_42_n.mp3
  everybody_here.mp3
  freedom_4_all.mp3
  grandpas_advice.mp3
  groove.mp3
  heartland.mp3
  he_loved_her_so.mp3
  highway_to_hell.mp3
  hit_the_ground_runnin.mp3
  i_feel_fine_today.mp3
  im_not_lost_im_exploring.mp3
  into_the_void.mp3
  its_alright.mp3
  i_will_be_there.mp3
  i_will_pass_this_way_again.mp3
  juiceboxwilly_hepcat.mp3
  just_an_illusion.mp3
  keepin_time_by_the_river.mp3
  king_of_the_brooklyn_delta.mp3
  lovermilou_ringingbell.mp3
  middle_aged_rock_and_rollers.mp3
  midnight_high.mp3
  mr_schwinn.mp3
  my_brilliant_masterpiece.mp3
  my_gallery.mp3
  on_the_river_road.mp3
  pouring_rain.mp3
  prayer.mp3
  rats_in_my_bedroom.mp3
  razor_serpent_and_the_dub_mix.mp3
  ruthbuzzy_pleasestophangin.mp3
  secret_love.mp3
  ships.mp3
  silence_the_thunder.mp3
  sleeping_beauty.mp3
  slow_burn.mp3
  standing_in_my_own_way.mp3
  take_no_prisoners.mp3
  takin_up_space.mp3
  Taylor_Dayne_Unstoppable.mp3
  the_laundromat_song.mp3
  the_old_dun_cow.mp3
  the_people_i_meet.mp3
  trip_trigger_avenue.mp3
  tru-luv.mp3
  unfortunate_man.mp3
  vertigo.mp3
  when_she_runs.mp3
  where_do_we_go_from_here.mp3
  words_of_earnest.mp3
  

• Powerful Video Analytics and Audio Analytics for Piwik

  10 novembre 2016, par InnoCraft — Plugins, Press Releases

  Over the years, one of the most frequently requested feature by users was to be able to measure how videos and audios are watched and engaged with on your website. We are finally able to announce that it is here ! We are very excited to launch Media Analytics, which will help you understand and grow your audience.

  This article is a showcase of the new powerful video and audio analytics product built for Piwik.

  Why media analytics ?

  We all love media content such as videos as they can make our experiences on websites and apps so much more interesting. A growing number of websites now utilize media files in one form or another : a video presentation of a product or service, a video tutorial teaching you how to do something or interviews with key speakers. Also many creators and distributors are publishing audio files such as podcasts or music songs, and even broadcasting live video events such as music concerts or an entire conference online.

  Whenever you publish videos or audio media on your websites or applications, Media Analytics provides you with clear insights on how your audience interacts with your content. It helps you see what content works and why – so you can better understand and further grow your business !

  

  Valuable insights in Real time

  

  See where your audience comes from.

  How will Media Analytics help me grow ?

  • Better understand your audience : who are the users playing videos and for how long, how often, and where have they dropped off.
  • Gain quick insights into how interaction with your media changes over time with easy to use graphs and report overviews.
  • Get closer to your users by seeing every action of your visitors before and after they utilized your media.
  • View valuable insights in Real time : ‘most popular content right now’, your real time audience map, and more.
  • See where your audience comes from. Drill down right from continents to specifics such as cities.
  • Share and export media analytics reports with your colleagues by creating custom email reports.
  • Video and audio players are supported either automatically (for Youtube, Vimeo, HTML5…) or via a simple custom player integration.
  • No data limit and 100% privacy and data ownership.

  Best of all, it is easy to use and understand, and integrates perfectly with Piwik. Media Analytics complements other reports to give you a 360 degree view of how your users engage with your content.

  Learn more on the official website : www.media-analytics.net

  How do I get Media Analytics ?

  All premium plugins come with our 14 day money back guarantee and 1-click installation & updates. Customers get all product updates for free.

  Learn more about Media Analytics Get it now on the Marketplace

  Media Analytics is available for purchase and download on the Marketplace.

  If you are not using Piwik yet, you can also signup for a free trial of Piwik Cloud (including Media Analytics !).

  Have a question about this product ? Get in touch.

• What's wrong with my use of timestamps/timebases for frame seeking/reading using libav (ffmpeg) ?

  17 septembre 2013, par mtree

  So I want to grab a frame from a video at a specific time using libav for the use as a thumbnail.

  What I'm using is the following code. It compiles and works fine (in regards to retrieving a picture at all), yet I'm having a hard time getting it to retrieve the right picture.

  I simply can't get my head around the all but clear logic behind libav's apparent use of multiple time-bases per video. Specifically figuring out which functions expect/return which type of time-base.

  The docs were of basically no help whatsoever, unfortunately. SO to the rescue ?

  #define ABORT(x) do {fprintf(stderr, x); exit(1);} while(0)
  
  
  
  av_register_all();
  
  
  
  AVFormatContext *format_context = ...;
  
  AVCodec *codec = ...;
  
  AVStream *stream = ...;
  
  AVCodecContext *codec_context = ...;
  
  int stream_index = ...;
  
  
  
  // open codec_context, etc.
  
  
  
  AVRational stream_time_base = stream->time_base;
  
  AVRational codec_time_base = codec_context->time_base;
  
  
  
  printf("stream_time_base: %d / %d = %.5f\n", stream_time_base.num, stream_time_base.den, av_q2d(stream_time_base));
  
  printf("codec_time_base: %d / %d = %.5f\n\n", codec_time_base.num, codec_time_base.den, av_q2d(codec_time_base));
  
  
  
  AVFrame *frame = avcodec_alloc_frame();
  
  
  
  printf("duration: %lld @ %d/sec (%.2f sec)\n", format_context->duration, AV_TIME_BASE, (double)format_context->duration / AV_TIME_BASE);
  
  printf("duration: %lld @ %d/sec (stream time base)\n\n", format_context->duration / AV_TIME_BASE * stream_time_base.den, stream_time_base.den);
  
  printf("duration: %lld @ %d/sec (codec time base)\n", format_context->duration / AV_TIME_BASE * codec_time_base.den, codec_time_base.den);
  
  
  
  double request_time = 10.0; // 10 seconds. Video's total duration is ~20sec
  
  int64_t request_timestamp = request_time / av_q2d(stream_time_base);
  
  printf("requested: %.2f (sec)\t-> %2lld (pts)\n", request_time, request_timestamp);
  
  
  
  av_seek_frame(format_context, stream_index, request_timestamp, 0);
  
  
  
  AVPacket packet;
  
  int frame_finished;
  
  do {
  
      if (av_read_frame(format_context, &packet) < 0) {
  
          break;
  
      } else if (packet.stream_index != stream_index) {
  
          av_free_packet(&packet);
  
          continue;
  
      }
  
      avcodec_decode_video2(codec_context, frame, &frame_finished, &packet);
  
  } while (!frame_finished);
  
  
  
  // do something with frame
  
  
  
  int64_t received_timestamp = frame->pkt_pts;
  
  double received_time = received_timestamp * av_q2d(stream_time_base);
  
  printf("received:  %.2f (sec)\t-> %2lld (pts)\n\n", received_time, received_timestamp);

  Running this with a test movie file I get this output :

      stream_time_base: 1 / 30000 = 0.00003
  
      codec_time_base: 50 / 2997 = 0.01668
  
  
  
      duration: 20062041 @ 1000000/sec (20.06 sec)
  
      duration: 600000 @ 30000/sec (stream time base)
  
      duration: 59940 @ 2997/sec (codec time base)
  
  
  
      requested: 10.00 (sec)  -> 300000 (pts)
  
      received:  0.07 (sec)   -> 2002 (pts)

  The times don't match. What's going on here ? What am I doing wrong ?

  ---

  While searching for clues I stumbled upon this this statement from the libav-users mailing list…

  [...] packet PTS/DTS are in units of the format context's time_base,
  where the AVFrame->pts value is in units of the codec context's time_base.

  In other words, the container can have (and usually does) a different
  time_base than the codec. Most libav players don't bother using the
  codec's time_base or pts since not all codecs have one, but most
  containers do. (This is why the dranger tutorial says to ignore AVFrame->pts)

  …which confused me even more, given that I couldn't find any such mention in the official docs.

  Anyway, I replaced…

  double received_time = received_timestamp * av_q2d(stream_time_base);

  …with…

  double received_time = received_timestamp * av_q2d(codec_time_base);

  …and the output changed to this…

  ...
  
  
  
  requested: 10.00 (sec)  -> 300000 (pts)
  
  received:  33.40 (sec)  -> 2002 (pts)

  Still no match. What's wrong ?