Saturday, 10 January 2015

Do You Need A Media PC?

Media PC

Leo Maxwell debates the pros and cons of using a PC as a DVR and media centre

Broadcast TV, whether delivered via cables or over the air from terrestrial or satellite transmitters, is still very popular in this country, but the modern trend for increasingly fast broadband connections means that some users are ditching TV tuners altogether and moving to on demand media sources. A wide range of devices designed to meet that need are appearing on the market: Chromecast, Roku, AppleTV and NowTV amongst them. The obvious advantage is that you can watch what you want, largely when you want to - which sounds great, there are limits, though.


Streaming services such as Netflix or Amazon may only have content available for a limited period, though. The BBC recently extended its iPlayer 'watch window' to 30 days for most content, but some services limit it to just days. Streamed content is not constantly available, nor is it easy to store it offline. Even if the entire visual and audio archive was available all of the time online, not all of us have broadband with the bandwidth to stream HD media. Some providers cap downloads, some throttle big users and not all networks are reliable.

Not all the online sources are faultless either. Although the big names generally offer a good service if you have the bandwidth, many of the others on offer can only deliver poor picture and sound quality with endless 'buffering' messages. Sadly areas where the TV signal is poor often coincide with poor broadband provision too, but satellite provides an alternative to both - either via Sky or the FreeSat service.

Watch, Skip, Watch, Skip


Let's face It, although we know that the advertising pays for the content, there is little doubt that most of us would avoid it if we could. In fact in the past there were often peaks in power demand during the commercial breaks in popular programs such as Coronation Street, as many viewers used it as an opportunity to put the kettle on. Understandably, commercial on-demand streaming players prevent you from skipping adverts. Even subscription services are not all ad-free.

Which makes one of the biggest advantages of broadcast TV over on-demand content the 'skip forward' button. I personally always watch commercial TV time-shifted, simply because it means I can skip forward to avoid advertising. Shameful, I know, but in my defence, I have never paid any attention to them anyway.

In time, IPTV will almost certainly replace most broadcast TV, but at present a large percentage of us still want direct access to terrestrial TV and the ability to record it for watching or (re-watching) in reasonable quality at a time of our own choosing, whether that is days, weeks or months later. How we do this is largely a matter of which hardware and software options we choose. Having made the decision to record Broadcast media, we need to choose between proprietary PVR (Personal Video Recorder) or PC-based solutions.

Simple Vs Functional


There is always a balance to be struck between how much a device can do, and how easy it is to use. Every added feature means a little more complexity. PVR devices are generally simple to use, compact, energy efficient and mostly maintenance free, but they are generally more limited in terms of access and flexibility.

Due to hardware stream decoding and image processing these devices have low power requirements. A 1GHz processor and 512MB of RAM are more than adequate to handle two HDTV streams along with the generally narrow additional functionality they provide. In contrast, a media PC offers much greater flexibility and can fulfil multiple roles, albeit at the cost of increased complexity and higher performance requirements.

In the past even custom-made media PCs have generally been quite large, with higher energy requirements and often noisy cooling fans, but nowadays a PC can be fitted into very compact enclosures. An energy efficient CPU/GPU combination can obviate the need for active cooling. Some smaller cases have external power supplies and VESA mountings so they can actually be fixed to the back of a TV or Monitor, with USB tuners to avoid the need for PCI card.

Software


The software in a PVR is, by nature, limited to whatever software the manufacturer supplies with the device - though there may perhaps be an app store for free or paid-for add-ons. Of course, a media PC -not being limited to a single purpose - is infinitely more customisable.

There is a wide range of media software available for PCs, including Windows Media Player and many other solutions such as VLC or Plex. I have in the past used two free open-source solutions, MediaPortal on Windows, and MythTV on Linux - both of which were polished, mature projects that worked very well. I will be looking at them in more depth later in the series.

Moving Up To HD


This project started when I needed to replace an ageing living room media PC. There are many PVR solutions on the market, but Humax consistently score highly in reviews. I purchased the YouView branded version, which is essentially the Humax T2000T PVR with all the main CatchupTV applications built in. Some PVRs have more features, in fact the Humax in its standard incarnation has a Web Portal, USB playback, DNLA Streaming and a bigger app store.

The biggest redeeming feature of the YouView box is the 'scrollback' EPG, which allows you to view available output for seven days in each direction, and launches the correct Catchup player for programmes shown in the past seven days. This is nicely integrated, but some shows are unavailable in the 'past', notably most films (presumably due to rights issues).

At first, I was very pleased with it, but after a while I became aware of the limitations of the PVR compared to my old box.

Storage on a PVR is obviously limited to the hard disk supplied with it - and, although some offer USB or eSATA ports, content is often encrypted. This means that archiving from most PVRs is only possible by using another device, such as a Hauppuage HD-PVR unit to record in real-time from an HDMI output to a PC. A dedicated media centre PC may be able to 'format shift' content to DVD or Blu-ray for backup purposes.

The main advantages of the PC platform that became apparent were flexible scheduling, and the ability to record more than two channels at once. For example, setting a series record on the Humax records the whole series if it there is the space to do so, but on the MythTV box I can set it to record one copy of every episode of any given program - and it will do that forever, regardless of what series of the show the episode comes from. This means it can pick up missed episodes when they are on as repeats until the complete run of the show is recorded.

Although the YouView catchup functionality makes up for some of that, it is quite limited in comparison. The main catchup applications are all available on an increasing number of alternative platforms, so it's a functionality that's easily replaced. After a fairly short timespan, I found myself getting frustrated with the limits of the Humax and decided to augment it with a new low-power PC to function as a back-end server. As a bonus, my media PC does not necessarily need to live under the TV, it can be hidden away elsewhere, and I can stream content to a small device connected to the TV or indeed any device on my home network.

A dedicated PVR may score highly with regard to simplicity and ease of use, and for some people that will be enough, but the scope of features a home media PC can offer makes it a winner for me.

In an upcoming article, I will look at building a multi-purpose media PC and what that entails.