Flash Templates Tutorials - SAVING FILES IN GIF AND JPEG FORMATS - Saving in JPEG format
Saving in JPEG format
To store photo images, JPEG format ensures the minimal file size, although losing the image quality. However, JPEG format distorts images lesser than the reduction of color palette. When saving JPEG images there is JPEG Options dialog box displayed.
Let's consider the options listed in the dialog box, and the impact on the image.
* Matte. It would be more appropriately to call it "imitation" of transparency. The option is available for modification, if the image contains transparent area. Unlike GIF, JPEG format does not support transparency, and we should set the color for filling these areas. An appropriate color may be selected from the drop-down list.
* Image Options. Quality is the adjustable property. It serves for specifying the image compression ratio. The lower the property value, the higher compression is (smaller file size). Image quality may deteriorate significantly with an increase of compression ratio.
TIP. In most cases the best compression ratio is about 7. However, in each case it should be selected individually. This is facilitated by the fact that during selection of JPEG format properties, how the compression effects the image is displayed in the image window. Using the mouse, you can "scroll" image. By clicking the mouse while holding Ctrl key pressed, you may enlarge the image and to reduce it with Alt key pressed.
* Format Options. Most of the web browsers support two options of JPEG format: basic and progressive (advanced). The basic, or consistently displayed format, creates images by displaying it on the screen line-by-line, and progressive displays images on a screen in a few passages. Baseline Optimized format differs from Baseline ("Standard") in the fact that using the advanced Huffman's coding method reduces file size by 5-10%. When selecting Progressive format, image is not displayed line-by-line, but in a few passages. At each of the passages a complete image is displayed, the quality of which is improving passage to passage. Scans property specifies the number of passages. The higher the value of this property, the smoother improves the image quality. Also, with a greater number of passages the file takes a bit less space.
* Size - you can assess the file size before burning it on the disc. From the drop-down list you can select the data transfer speed. Aside from the list there is time displayed necessary to load images on the user's computer. If you are dissatisfied with the image speed download, you will have to sacrifice the image quality and reduce Quality property.
TIP. When selecting the loading speed, it is wiser to stay on average one. If you orient the users owning the latest technological advances, there is a risk of losing the lion's share of the audience. An excess reducing file size at the expense of quality is not always acceptable.