HDV Sony, Canon, and Sharp
HDV: A low-cost alternative to uncompressed HD (high definition), developed in September 2003 by JVC, Sony, Canon, and Sharp. The HDV format records high-definition MPEG-2 transport streams to Mini DV tapes.
HDV uses long GOP (group of pictures), which contains an l-Frame, or Intra-Frame compressed image, once every 1 5 frames. The P- and B-Frames (or Predictive and Bi-Directional) will reference images and data that don’t change from the l-Frame. For instance, if a person is walking outside, the only part of the frame that is re-drawn and not referenced to the l-frame is the person who is walking. This keeps the data small enough to go to Mini DV tape.
• AVCHD: Advanced Video Codec-High Definition; another type of compression for HD production. Instead of HDV’s mandate of recording to tape, AVCHD records to either a DVD disc, a Hard Drive Disk (HDD), or a memory card.
Developed by Sony and Panasonic in mid-2006, AVCHD is compressed to MPEG-4 using H.264 encoding, and it has some similarities to HDV, such as a 4:2:0 sampling.
