The picture resolution on your average DVD is 720i (the i stands for interlaced, meaning it can suffer from flickering) and even the highest capacity DVDs could only hope to store 17 gigabytes of data (the average is 4.7). In comparison a Blu-ray disc can hold 50GB. Normally the image and sound from a film would be encoded and compressed to squeeze onto a DVD but with Blu-ray nothing is compressed, meaning you retain the best possible version of the film. The Dolby Digital Plus and Dolby TrueHD sound formats are clearer and the image boasts vibrant colours that DVD could never hope to match.
With all that extra storage space, studios can create faster and more elaborate menus with special features that can be accessed whilst you're viewing the film (no more skipping back to the bonus features screen to slowly flick through all the options). Want to see how they filmed a particular sequence in the movie without pausing it? Just access the pop-up menu and you can watch both at once. This is called Bonus Viewing or PIP (picture-in-picture) and it allows you to watch video commentaries, storyboards or behind-the-scenes featurettes alongside the film.
Studios can also include more of these special features on Blu-ray since storage space isn't an issue any more. Some releases have already been 2-disc sets and if both discs were filled to the brim that would be over 18 hours of footage to watch with no compression or sacrifice of quality whatsoever. If that's not enough there's always BD-Live, an interactive online feature that uses your Wi-Fi/Ethernet connection to download the latest extras relating to individual titles. You can even record your own video commentaries and upload them to BD-Live for public torture- er, enjoyment.
Blu-ray also offers 7.1 surround sound, interactive games, D-Box Motion Code so your D-Box chair will rumble with the action (one for the ladies) and you can bookmark all your favourite scenes. Since all HDTVs are widescreen, the original theatrical ratio from a film is retained so there's no anamorphic stretching that's usually necessary with DVDs.
The benefits are endless, so what are you waiting for? With recordable Blu-ray players starting to make the rounds and companies like Panasonic, Samsung and Mitsubishi deep into creating 3D Blu-ray technology using digital home cinema projectors with a 3D-ready MPEG-4 decoder, the future of home cinema is Blu-ray through and through.
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