Question

Read the following topic then explain what kind of compression strategy does MPEG uses?

please no copy answer and no hand writing

Video Compression

Why do we need Video Compression?

One of the challenges of making a proper digital video is the large file size. Every second of uncompressed digital video requires 30MB of storage, which make it also hard to deliver digital videos. Compression is the key to face such challenge.

What strategies can we use to compress a video?

Intra-frame.

Inter-frame.

Variable bit rate (VBR) / Constant bit rate (CBR).

Example: MPEG (Motion Picture Experts Group)

MPEG is a codec for video that uses both intraframe and interframe compression strategies. A video of a newscaster reading a story contains a series of frames with very little motion. One frame may differ from another only in the position of the lips of the speaker, while others may shift only slightly more as she moves her head or shoulders.

MPEG saves some frames as complete compressed imagesà I-frames (for intraframe compression).

Subsequent frames record only the parts of the image that have changed between I-frames and discard the rest of the image:

P-frames: record significant changes

B-frames: record smaller changes.

When an MPEG file is decoded:

The processor reassembles the dropped frames by using I-frames as references to re-create the intervening frames with the changes stored as P-frames or B-frames.

Answer 1

MPEG 4 is one of the compression algorithms that can be used for a 120-minute film. The original 120 minutes film can be compressed to about 300 MB.

Video compression is used to remove unnecessary information. Various types of documents are compressed using compression algorithm and eliminate information or subparts that are not required,

H.261 encoding technique is based on discrete co-sine transform and allows full encoding of certain frames of Intra-frame, while encoding difference between other frames Inter frames.