Streaming Video – Not Really Part Two!


Last week we introduced many of you to the Roku streaming TV device with an eye toward a short article about streaming video to the aircraft from satcom-based and terrestrial delivery sources. We told you that we would cover that subject this week – not! That’s next week because we wanted to get a bit more information about the existing delivery of streamed inflight entertainment onboard aircraft via the traditional IFE hardware.

First we asked Rich Salter, Lumexis techno-guru, to tell us about the formats used today and he told us: “Most airlines are using MPEG1 and MPEG2 for their AVOD systems now (about 50/50 MPEG1 and MPEG2), and MPEG1 is at 1.5 Mbps constant bit rate while MPEG2 is at 3.5Mbps constant bit rate per WAEA spec. MPEG4 is not yet being used much on the embedded IFE, but it is on the portable media players (IMS, digEcor, etc.), and the bit rate is about 2Mbps. We have been saying that the High-Def MPEG4 will need to be at about 8Mbps (still a very small bite out of bandwidth on our fiber system!). Internet TV can use different bit rates other than IFE (those bitrates I gave are for IFE only). So I don’t think we can tell if it’s (TV Streaming Video) is MPEG1 or MPEG2 by the bit rate being 1.5Mbps. Let me ask my trusty Internet video expert John to weigh in on this one.”

Next, we heard from another IFE techno-wizard, John Holyoake, about the TV side of streaming – he told IFExpress: “Rich is correct. There are many different players and formats used to stream internet video, including Flash, Quicktime, RealPlayer, Windows Media, Divx, etc. Most have adopted some variation of MPEG-4 for minimum bitrates and good quality. But MPEG1 and MPEG2, and proprietary codecs are still in use, so you can’t tell which codec is used, based on bitrate alone.”

And lastly, we checked our data with content guru, Michael Childers and he opined: “WAEA 0395 codifies MPEG-1 at 1.5Mbps and MPEG-2 at 3.5Mbps. WAEA 0403 codifies H.264 and WMV at 1.0<Mbps. The “1.0-and-up” for H.264 and WMV was done that way to enable hardware providers to use higher bitrates than 1.0Mbps for larger screen sizes, and it is believed that some may go as high as 1.5Mbps. MPEG-1, which is the most-used codec in IFE currently, was designed to compress VHS-quality digital video down to 1.5Mbps at resolution of 352×240, or “SIF” resolution. MPEG-2 was designed to improve upon MPEG-1 and outperforms MPEG-1 at 3Mbps and above. WAEA 0395 codifies MPEG-2 at 3.5Mbps. There is very little MPEG-2 use in IFE today, but some. The MPEG-4 codecs are: a) MPEG-4 Part 2, Visual, which only improves upon the bit efficiency of MPEG-2 by about 20%, and hence is not being used in IFE today; and b) MPEG-4 Part 10 (AVC), also called H.264 Advanced Video Coding, and VC-1/SMPTE 421M which is the same as Windows Media Video. These were designed to do at 1.0Mbps what MPEG-2 does at 3Mbps.”

So, there you have it, onboard IFE system content streaming in a nutshell. next week we will talk to a few of the inflight streamers and dreamers about the next generation of streaming content. Remember, bandwidth is everything!

Here are some links for more detailed information:

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