Image Compression Examples
So, what should I use, GIF or JPG?
Both. Each has its uses and advantages. For web authoring, the majority of your images will probably be GIF's. With a GIF you can get right in there and manipulate the image and its colors on a pixel level.
When should I use a JPG?
When your image is a photograph that has many colors, blends and gradients, and when exact color matching isn't critical.
When should I use a BMP?
Never. A bitmap is totally uncompressed... the files sizes are HUGE. (When we speak of "compression", we're not talking about the width and height of an image... we're talking about it's file size.)
Here are two images...
The car is a photographic image and the bee is a drawn image with relatively few colors. Both images start out as 16 million color bitmaps and both are a whopping 116 KB. Each is saved below as a progressively more compressed JPG and a progressively more compressed GIF. (Compressing a GIF is largely a matter of reducing the number of distict colors in the image. For more on this topic look here.) You'll quickly see drastic differences in how, and how efficiently these images compress.
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So, what should I use, GIF or JPG?
Both. Each has its uses and advantages. For web authoring, the majority of your images will probably be GIF's. With a GIF you can get right in there and manipulate the image and its colors on a pixel level.
When should I use a JPG?
When your image is a photograph that has many colors, blends and gradients, and when exact color matching isn't critical.
When should I use a BMP?
Never. A bitmap is totally uncompressed... the files sizes are HUGE. (When we speak of "compression", we're not talking about the width and height of an image... we're talking about it's file size.)
Here are two images...
The car is a photographic image and the bee is a drawn image with relatively few colors. Both images start out as 16 million color bitmaps and both are a whopping 116 KB. Each is saved below as a progressively more compressed JPG and a progressively more compressed GIF. (Compressing a GIF is largely a matter of reducing the number of distict colors in the image. For more on this topic look here.) You'll quickly see drastic differences in how, and how efficiently these images compress.
Back To MAIN Lesson