Content deleted Content added
m fixed (via WP:JWB) |
|||
Line 96:
| [[DVD|DVD Video]], [[Blu-ray]], [[DVB]], [[ATSC]], [[SVCD]], [[SDTV]]
|- style="text-align:center;"
| [[DV (video format)|DV]]
| 1995
| IEC
Line 188:
==Intra-frame video coding formats==
Interframe compression complicates editing of an encoded video sequence.<ref name="Bhojani">{{cite web|last=Bhojani|first=D.R.|title=4.1 Video Compression|url=http://shodh.inflibnet.ac.in/bitstream/123456789/821/5/05_hypothesis.pdf|work=Hypothesis|access-date=6 March 2013}}</ref>
One subclass of relatively simple video coding formats are the [[intra-frame]] video formats, such as [[DV (video format)|DV]], in which each frame of the video stream is compressed independently without referring to other frames in the stream, and no attempt is made to take advantage of correlations between successive pictures over time for better compression. One example is [[Motion JPEG]], which is simply a sequence of individually [[JPEG]]-compressed images. This approach is quick and simple, at the expense of the encoded video being much larger than a video coding format supporting [[Inter frame]] coding.
Because interframe compression copies data from one frame to another, if the original frame is simply cut out (or lost in transmission), the following frames cannot be reconstructed properly. Making 'cuts' in intraframe-compressed video while [[video editing]] is almost as easy as editing uncompressed video: one finds the beginning and ending of each frame, and simply copies bit-for-bit each frame that one wants to keep, and discards the frames one does not want. Another difference between intraframe and interframe compression is that, with intraframe systems, each frame uses a similar amount of data. In most interframe systems, certain frames (such as "[[Video compression picture types|I frames]]" in [[MPEG-2]]) are not allowed to copy data from other frames, so they require much more data than other frames nearby.<ref name="Jaiswal">{{cite book|last=Jaiswal|first=R.C.|title=Audio-Video Engineering|year=2009|publisher=Nirali Prakashan|___location=Pune, Maharashtra|isbn=9788190639675|page=3.55}}</ref>
| |||