A gray scale image(Black and white) that is 256 x 256 pixels has 65,536 elements to store whereas a typical 640 x 480 colour image has nearly a million such elements to store. For instance if we represent each element by 8 bits then the total memory space required for a grayscale image will be (65536 x 8 = 512Kb) and for color image it would be in Mbs. Now to store or transmit these images would require huge memory and bandwidth which is not always possible.
Consider the following image :-
in this image there is lots of white component then one red block and one yellow block. This very small image has 1.4KB of size. Its clearly visible that the above image has lots of redundancy in terms of the pixels.
If we can represent the image like x*(white) + y*(red) + z*(yellow)+ p*(black)then it would reduce the memory/bandwidth requirements and we can generate the original image at the destination or while viewing.
similarly, Natural images has lots of redundancy which can be removed to compress the image before transmission or storing. Videos generally are 30 frames per second and these frames are generally very similar in nature which gives the feeling of continuation in videos. Since these frames are very similar or identical most of the time, they can be compressed as well.
This compression is required to reduce the BW and memory requirements to store and transmit the images and videos.
Consider the following image :-
in this image there is lots of white component then one red block and one yellow block. This very small image has 1.4KB of size. Its clearly visible that the above image has lots of redundancy in terms of the pixels.
If we can represent the image like x*(white) + y*(red) + z*(yellow)+ p*(black)then it would reduce the memory/bandwidth requirements and we can generate the original image at the destination or while viewing.
similarly, Natural images has lots of redundancy which can be removed to compress the image before transmission or storing. Videos generally are 30 frames per second and these frames are generally very similar in nature which gives the feeling of continuation in videos. Since these frames are very similar or identical most of the time, they can be compressed as well.
This compression is required to reduce the BW and memory requirements to store and transmit the images and videos.
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