Unit 30 Task 8

Task 8b

Describe and evaluate the impact that file format, compression techniques, image resolution and colour depth have on file size and image quality.

(D2) 18th March.

GIF Images

In this section I have chosen to adjust the colour depth of the image to show the effect that image resolution has on an image. The image in the top left is the original image of a fairly high resolution. The image in the top right has been changed to a higher resolution so that the multiple colours in the image seem to blend better, whereas the image in the bottom left has been changed to a lower resolution than the original image, so the multiple colours seem more divided and block-like. The image in the bottom right has been set at a very low resolution so the colours are basically completely individual blocks of a single colour. As the image resolution is lowered, the file size becomes smaller too due to the lower quality of the image.

JPEG Images

In this section I have changed the compression technique to show how it effects the quality of the image. The top left is the highest resolution, with the top right being second highest, bottom left being third and bottom right being fourth. As you can see, as the resolution is lowered, the images don't seem as smooth and have become more pixelated. In this set of images, as the compression technique is lowered, the file size becomes smaller as the image is of a much lower quality.