NTT Laboratories Compresses 1080p Signals into a 1.8 Mbps

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http://techon.nikkeibp.co.jp/english...050422/104075/

At the NAB2005 event, NTT Cyber Space Laboratories unveiled H.264 (MPEG-4 AVC) encoding technology that uses offline (anti-real-time) processing to enable 1080p HDTV signal compression at an encoding speed of up to 1.8 Mbps. Although the compression is slow, the low 1.8 Mbps encoding data rate is definitely the worlds lowest. Picture quality is "equivalent to that of MPEG-2 encoded at 10-20 Mbps," said a company spokesperson.

With the aim of storing a huge amount of images, the company pursued high-quality picture at high compression rates. Monitoring encoding parameters such as quantization values in encoding mode, the system based on the new technology repeats compressing an original HDTV signal whenever an optimal parameter has been found. Through repetition of parameter selection and compression tens of times, the compression rate is gradually boosted.

This technology, however, only allows for slow compression. According to the company, approximately 10,000 times the playtime of the original content is needed to compress it into a 1.8 Mbps stream using the current PC based software.

Picture quality is almost equal between an ITU/ISO joint model (JM, left) and a picture compressed at x 1.5.