Posts Tagged derivatives

Audio and Video improvements

April 14, 2009 at 4:18 pm · Filed under audio, movies ·Tagged , , , ,

Hi Patrons,

Yesterday we made live a large update to the way we create the audio and video displayed on our site.  Most folks might not notice the changes, so here’s a rundown:

For Audio:

  • We can now read and make mp3s from 24-bit Flac files.  This has been requested for many years and we are thrilled to get it working.
  • The Ogg audio files that we create from audio files will now be using an updated “libvorbis” library.  (The library we were using before today was from 2001! 8-) )
  • We are no longer making 64kb MP3s (or zips or m3u playlists of those files).  This was a judgement call — given how poor the sound quality is for these files and the fact that most people are getting more and more bandwidth to their devices and computers.
  • Simplified back-end system, relying more and more on “ffmpeg” for format conversion.
  • We will now (try to) make derivatives from “.aac” (Advanced Audio Coding) files and “.ra”/”.rm” (Real Audio) files.
  • General ability to read more kinds of audio files more reliably.

For Movies:

  • The Ogg Video files that we create from movies files will now be using an updated “libvorbis” library for their audio.  (Previously we were using the “non reference” library ogg encoder.  Now we are using the much asked for and newer “libvorbis” library).
  • Updated ffmpeg to v0.5.   This allows for a much wider range of source audio/video containers and codecs.  We will be able to derive HD-quality video formats like DV-50 and DV-100.   (For those interested in ffmpeg, changelog).
  • Better detection of widescreen movies (so less of our movies on our site will incorrectly appear “squooshed”).
  • General ability to read more kinds of video files more reliably.
  • Noting the prior point, we were able to get streaming videos for about 170 TV archive items that we could not process previously.

Enjoy!

–Tracey Jaquith

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New strategy for Internet Archive movies!

November 25, 2008 at 6:38 pm · Filed under movies ·Tagged , , ,

We have rebuilt all of our nearly 200,000 videos at the archive!

[We finished this Dec 1, 2008]

Related cross-blog with OLPC.

Here is a table-based chart of which video formats will be “derived” into which formats (we are creating 4 formats per video now):

http://www.archive.org/help/derivatives.php

 

Improvements and Changes from our prior movies techniques:

  • We will make a new Ogg Theora (with Vorbis audio) opensource/free-based video derivative.  This derivative will play natively in Firefox 3.1 release (v3.1 is due around the end of 2008).
  • We are re/making h.264 MPEG-4 derivatives.  We have updated the format to work with lighttpd “mod_h264_streaming” (which allows jumping into a movie at a specified time) but in the process will be losing the ability to serve/stream this file with RTSP.  This derivative also plays in the Adobe Flash plugin and plays on iPods/iPhones.
  • We are removing older 64kb and 256kb MPEG-4 derivatives.  With “progressive download” support becoming ubiquitous, even modems and phones are doing much better with downloading larger files.
  • We are removing older .flv “Flash Video” derivatives.  Since the much better quality h.264 derivative plays in recent flash plugins (as well as many other devices and browsers), the flash video alternative is seen as less ideal.
  • We are removing older .mpg MPEG-1 derivatives.  Their usefulness has declined in recent years, especially compared to h.264 alternatives.
  • We are remaking our animated GIFs.  They attempt to make 30 thumbnails from each uploaded video.  We now evenly space them across the entire video.
  • We are remaking our Thumbnails.  Similar to the GIF, we are spreading them across the videos better, and making less Thumbnails for items with *many* videos.  Additionally, we are renaming the thumbnails to indicate the second position in the video they were created at.  This will allow for the next bullet item…
  • We have developed the ability to jump into videos by clicking on the thumbnail image (to go to that scene!)  We are finalizing the URL / permalinks for these “jump into video” URLs and will release this live to the public as soon as we can.

-tracey jaquith

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