By Tom Coughlin
SMPTE Entertainment Technology in the Internet Age, June 18, 2013: IMF addresses a significant problem in creating alternative versions of a piece of content to meet language, subtitle and other requirements for various markets. According to Howard Lukk from Disney Studios up to 35,100 versions of a single piece of content are possible. IMF is a master file format that allows mezzanine level data compression and stores differences between versions rather than flattened linear versions. This saves storage space and makes management and repurposing of content much easier. Pierre Lemieux of Sandflow Consulting said that IMF stands between the source master (digital intermediate) and deliverable content for distribution channels.
IFM reuses proven technologies developed for digital cinema. It synchronizes content essence and metadata and provides a composition timeline broken into segments composed of sequences and captions. An Output Profile List (OPL) governs specified transformations of the essence. According to John Hurst of Cinecert most IMF files are XML format.
Content delivery over the internet is increasingly popular but that popularity has dangers. Mark Watson of Netflix says 84% of their customers stream video at least once per week. YouTube has 13 billion videos with an average user viewing 401 minutes/month. Internet video traffic is now the majority of bits transferred through the internet and without new compression and delivery technologies video streaming could "break" the Internet, especially with even larger 4K video files on the horizon to feed new high resolution consumer TVs.
Adaptive Dynamic Streaming over HTTP (DASH) is one important element in conserving bandwidth assets. DASH features seamless adaptive streaming of content. Will Law from Akamai and Jesse Rosenzweig from Elemental spoke about DASH. 9 companies are providing players today for DASH and they believed that Adobe and Microsoft would switch to DASH in the future, leaving Apple as the only remaining proprietary streaming format.
New compression technology will also help control internet traffic, particularly for 4K content. One conference participant told me that MPEG H.265 encoding (which promises up to a 50% additional compression beyond H.2645) requires 2-3 X additional overhead for decoding (at the user). However the processing load at the source is much greater and to get the best quality delivery content about 100 X more overhead is required.
IMF and DASH provide a framework for digital content delivery over the Internet. Combined with HEVC compression (MPEG H.265) these technologies pave the way for increases in video streaming in a world where many people don't want to physically possess or even have a local copy of content. These technologies can satisfy that customer demand for more content without exceeding available bandwidth.
Tom Coughlin, the founder of Coughlin Associates (http://www.tomcoughlin.com) has over 30 years of magnetic recording engineering and engineering management experience at companies developing flexible tapes and floppy disc storage as well as rigid disks at such companies as Polaroid, Seagate Technology, Maxtor, Micropolis, Nashua Computer Products, Ampex and SyQuest.