Water in New Zealand and are of varying types and origins. Many of the lakes in the central North Island area are volcanic crater lakes, while the majority of the lakes near the Southern Alps were carved by glaciers. Hydroelectric reservoirs are common in South Canterbury, Central Otago and along the Waikato River. Over 180,000 kilometres of rivers has been mapped in New Zealand, the longest being the Waikato River with a length of 425 kilometres and the largest river by volume is the Clutha River with a mean discharge of 533 cubic metres per second. New Zealand has many notable waterfalls, some of
H.264/MPEG-4 AVC Digital Satellite TV quality as current MPEG-2 implementations with less than half the bitrate, with current MPEG-2 implementations working at around 3.5 Mbit/s and H.264 at only 1.5 Mbit/s. Sony claims that 9 Mbit/s AVC recording mode is equivalent to the image quality of the HDV format, which uses approximately 18–25 Mbit/s. To ensure compatibility and problem-free adoption of H.264/AVC, many standards bodies have amended or added to their video-related standards so that users of these standards can employ H.264/AVC. Both the Blu-ray Disc format and the now-discontinued HD DVD format include the H.264/AVC High Profile as one of three