Despite supporting almost identical video and audio codecs, Blu-ray disks hold 20GB more data than the 30GB capacity HD-DVDs.
Compression engineers can utilise this extra space to improve quality by achieving a higher bit rate and making up for lossless audio streams. Sony is making the most of this slight technical advantage by promoting Blu-ray as superior to HD-DVD, according to Video Business.
“It’s important, especially in this phase, that we make sure we are showing the absolute best quality in video and audio, and 50GB accomplishes that,” said Sony worldwide president David Bishop.
A more impartial view comes from the encoders responsible for Nine Inch Nails: Beside You In Time, which was released on both HD DVD and Blu-ray. An FAQ document on the NIN Web site acknowledges the technical differences, but claims the average viewer would not tell the difference:
“Technically speaking, the video quality of the Blu-ray version has a slight edge over the HD DVD: It was encoded at a slightly higher bit rate due to the Blu-ray spec's higher bandwidth capabilities for encoded video streams. However, this difference is nominal and would only be noticeable by a pair of well-trained eyes on an extremely expensive professional 1080P monitor.”