Zencoder continues its rapid expansion of transcoding offerings and achievements with today’s announcement that they are now ready to offer optimized HTTP Live Streaming encoding (HLS) for iPhone and iPad applications . They say it can create smaller files with no loss of quality.

Zencoder says their ‘highly-optimized’ encoding for iOS HTTP Live Streaming can save up to 10% in file size and streaming bandwidth. Isn’t optimized an absolute? I could go off on a Sheldon Cooper tangent here about that particular marketing lingo, but I’ll refrain.

So the new Zencoder service allows you to create HTTP Live Streaming (HLS) videos with the MPEG-TS format and because of their segmenting tools they are able to offer you much better streaming and lower file sizes for storage.

According to their news release:

Zencoder offers the only optimized HTTP Live Streaming implementation available in the cloud. In tests run by a third party, Zencoder segmenting produced files with 70% less overhead than Sorenson Media, up to 84% less than Encoding.com, and up to 50% less overhead than Harmonic’s ProMedia Carbon.

The MPEG-TS (MEPG Transport Stream) format uses H.264 video and AAC audio (HE-AAC or AAC-LC) and, according to the Apple in the specification of the HLS protocol:

A multimedia presentation is specified by a URI to a Playlist file, which is an ordered list of media URIs and informational tags. Each media URI refers to a media file which is a segment of a single contiguous stream.

To play the stream, the client first obtains the Playlist file and then obtains and plays each media file in the Playlist. It reloads the Playlist file as described in this document to discover additional segments.

Here’s a pretty groovy image that explains it from RGBNetwork:

HTTP Live Streaming Architecture

Anything that manages to preserve quality and give a 10% lower file size is something that I’m on board with. Here’s an FAQ of it all for developers and , I guess, video publishers.

Segment, Shmegment

According to Apple:

Shorter segments result in more frequent refreshes of the index file, which might create unnecessary network overhead for the client. Longer segments will extend the inherent latency of the broadcast and initial startup time. A duration of 10 seconds of media per file seems to strike a reasonable balance for most broadcast content.

It sounds like Zencoder might have found a better number to find their current optimization of the segmenting, or they read the FAQ and the others didn’t (purely speculation on my part and besides, it’s a joke, my comment, not the FAQ).

Wow, not that *I* read the FAQ, it’s chocked full of good info, I would definitely suggest hitting that link and reading, if you’re of a technical mind and really care about all of that. If not and you just want to have optimized videos to stream to iOS devices, then hop on over to Zencoder and check out what they’ve got on offer.

If it’s good enough for PBS, who is pushing around 2 million video streams a day through its PBS Kids iPad App  (launched in May, released today for iPhone and iPod Touch) which, and is using Zencoder, then it would probably work for many of you. They pushed 86 million streams in November alone through the app.

Last month, Zencoder encoded over 2 million videos and is, if we believe everything we read, the largest cloud video transcoding solution on the planet.