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New features coming along

By January 25th, 2012 Development No Comments

The Mac OS X version of the MobileBroadcast Client was released some days ago, but we are not less  busy with development now. Many new features will be released in the upcoming weeks. Namely, these are “adaptive bitrate”, which dynamically adapts the video bitrate to the available bandwidth of the Internet connection. Thus, freezing images or framedrops are much less likely, and the user doesn’t need to care about setting the exact bitrate before the transmission starts. A new “very low delay” mode allows a total latency of less than a second, making live conversations much more feasible. Finally, bundling even more than two Internet-connections is on the roadmap, giving better chances to establish a live link even under special conditions. Stay tuned, as the new features consecutively will be released within the next weeks.

First Mac screenshot

By December 2nd, 2011 Development No Comments

It has been very quiet in this weblog, but there is a good reason: We are all working hard to release the Mac OS X port of the client software in time. I hope we will still make it in December, or in January at the latest. Here is a first screenshot of the MobileBroadcast Client running in Mac OS X 10.7

SDI support

By October 12th, 2011 Uncategorized No Comments

One of the most requested features for the MobileBroadcast Client is support for SDI devices. For now, the software only supports capturing via FireWire.

Good news: SDI support is coming along! A new version of the client software will be released within the next weeks, which also supports capturing using the Blackmagic SDK, and thus all devices supported by this SDK. For notebooks, the UltraStudio SDI would be of special interest. If you are using a desktop PC for transmitting, the whole Decklink series will work.

But there are also some drawbacks using SDI: The client software consequently adheres to the concept of caching unprocessed data. If the computer’s CPU is to slow to encode video in real-time, the stream coming from the camera is cached on the hard-drive and encoded with a delay.

Instead of transcoding the stream directly, the incoming DV/HDV data are written to the hard drive, and at the same time read from the hard drive and encoded to H.264. The encoding thus went completely independent from capturing, and even slow CPUs wouldn’t cause a single frame drop. This was easy to achieve with DV or HDV captured via FireWire, because they have a data rate of only about 25MBit/s, which is not a problem for modern hard-drives, not even when writing and reading concurrently.

The situation is quite different with SDI: It delivers uncompressed video, which has already 270Mbit/s for SD and usually around 1.5Gbit/s for HD. Even for modern hard-drives, this is far too much for reading and writing concurrently, and thus captured data cannot be cached anymore. It has to be encoded directly to H.264, and the encoded data have to be cached afterwards.

The result is that you will have unrecoverable frame drops if your CPU is too slow to encode in real-time. When using SDI, an automatic “store-and-forward” delivery is only possible with very recent and fast laptop computers.

So as a conclusion, SDI will work well, but make sure to use one of the latest Core i7-2 processors with at least four cores! Slower computers will definitely cause frame drops.

On-camera mount

By October 5th, 2011 Uncategorized No Comments

There are many hardware vendors that offer video-over-cellular backpack solutions. Some of them even announced small and lightweight devices for on-camera mount, which is definitely a real advantage over these huge and heavy backpacks. MobileBroadcast in contrast is a software-solution and runs on normal notebook computers.

So, time to mount MobileBroadcast directly on the camera. Impossible, or at least impractical? Well, read on!

Indeed it was not an easy task to find a suitable notebook that is booth fast enough to perform the required video encoding, and small enough for being mounted on a camera. Also, the laptop should be applicable for outdoor usage, and at best even work in harsh environments or bad weather.

In fact, we found a computer that met all these requirements: The Panasonic Toughbook CF-19.

The latest Panasonic Toughbook is an awesome piece of hardware: While only having a size of 10,1″ and therefore being as small as a netbook, it delivers the full power of a Core i5-2520M, the newest generation Intel CPU with Sandy-Bridge architecture. This is more than enough processing power to do SD encoding in real-time, and even HD should work under most circumstances. No further external components are required for transmitting, since a Firewire connection and a 3G modem are already built into the notebook. Being fully ruggedized, it’s perfectly well suited for on-the-field usage.

For a first try, I sticked the laptop to the camera using some Velcro tape. While for a real-field application some additional brackets are highly recommended, it worked well for testing and could easily carry the 2.3 kg device.

The whole assembly has a weight of 10.5 kg, which is not what you would call lightweight, but acceptable for a camera operator. Especially for getting some breaking news on air, this is certainly a decent solution.

Concerning the price, the Toughbook is more expensive than what we call “standard” hardware, but still much cheaper than specialized devices from other vendors. And it really looks promising not only for running the MobileBroadcast Client on it, but for video applications on the field in general.

Thanks to FF COMPANY OFFICE SOLUTIONS for providing the Toughbook!

Hardware encoders vs. consumer type notebooks

By September 26th, 2011 Technical No Comments

A number of hardware solutions for video streaming over mobile networks appeared over the last years. Most of them are backpack solutions. And although I have not seen a piece that really works for everybody, you can already see the first on-camera mount devices on the market.

Mbcast.com is only providing a software solution instead of a special mobile device. Why is that? Well, the answer is simple: Because special hardware devices are obsolete.

One device I’ve recently seen had some very interesting features, but the specs where more than disappointing: The machine weighed more than 12kg (without batteries) and had an electrical power consumption of 150W. This is absolutely useless when it comes to a real field application, especially if it should be operated by a single reporter.

Another well known device has some better hardware specs, but only if you can afford it: They provide it on a rental base, but the smallest available package (only including very limited transfer-time) costs more for a single month than buying a decent laptop and using it for years.

What these guys seem to have forgotten when they designed their hardware years ago, is a very famous theory in computer science, called Moore’s Law. The theory mainly describes that computers double their performance every 18 months (some sources state a different time, but that actually doesn’t make much difference in the result). And indeed this trend has continued for more than half a century.

To cut a long story short: Computers became incredible fast in the last years, and modern CPUs are beating most hardware encoders hands down. Notebooks have all the hardware built in to perform the tasks of encoding and streaming, and they have many advantages over specialized hardware. They are much cheaper, there is plenty of different vendors and models to choose from (from fancy designed lifestyle notebooks up to fully ruggedized outdoor devices), and they are of course much easier to get. With support for external devices for capturing SDI or HDMI coming along, there is definitely no drawback in using laptop computers compared to specialized hardware.

And so we are glad to be able to say: Let the new generation of netbooks come. Mbcast will only work even better on faster machines!

Why mbcast.com delivers the best image quality

By September 25th, 2011 Technical No Comments

The heart of the MobileBroadcast Client is actually one of the greatest pieces of software I’ve ever found: The x264 encoding platform, a software implementation of the well known ITU-T H.264 standard. x264 development was started by some developers of the famous VLC media player, which in turn started as a project from École Centrale Paris, a prestigious engineering school in France. Today, it has a large developer community, with contributers from companies, universities and private software engineers all over the world.

So, what’s special about x264? Well, it’s currently the best available video encoder that can be found. This is not only a claim, but also confirmed by several scientific codec comparisons. For instance, an institute at the Lomonosov Moscow State University evaluates different codecs within regular intervals. For the third time (and for the second consecutive year), x264 clearly won over several other well known encoders with famous names in the industry. Don’t believe? Have a look at the Seventh MPEG-4 AVC/H.264 Video Codecs Comparison.

But beating all the others concerning image quality still does not make a good encoder. Another main factor is speed, and this is where another strength of x264 is revealed: It’s heavily optimized for modern CPUs using brilliant hand-coded assembly routines, and thus makes use of all the technical capabilities recent Core i5 and Core i7 CPUs can offer. Especially since Intel launched it’s Nehalem architecture around two years ago, software encoding became faster on normal desktop CPUs than on specialized hardware encoders. And with the new Intel-Sandy-Bridge architecture that came out in early 2011, encoding became even faster.

But besides all this technical evidence on x264, one event impressed me most: At the recent IBC, I was talking to a staff member of a very well known codec manufacturer, and asked about how their H.264 implementation compares to x264. Without a second of consideration he admitted: “They are better.”

At the IBC2011

By September 24th, 2011 In the public No Comments

MobileBroadcast recently celebrated it’s launch at the IBC2011. A good occasion to launch a new weblog and post some photos!

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