Resizing Images

542

Fireworks Zone

107

1715

12-11-2009

Description

In this article you will learn about the different methods of interpolation in Fireworks and the technique to downscale and upscale a bitmap.

Requirement

All Fireworks versions.

Article

1. Interpolation options

For interpolation you can select one of four different scaling methods for bitmaps (and only bitmaps) that Fireworks uses to interpolate pixels when images are scaled (downscale and upscale).

1. Bicubic interpolation gives the sharpest and highest quality most of the time and is the default,
2. Bilinear interpolation gives sharper results than Soft interpolation but not as sharp as Bicubic,
3. Soft interpolation, which was used in Fireworks 1, gives a soft blur and eliminates sharp details. It is useful when others produce unwanted artifacts,
4. Nearest-Neighbor interpolation results in jagged edges and sharp contrasts with no blurring. The effect is like zooming in or out on an image.

In image processing, bicubic interpolation is often chosen over bilinear interpolation or nearest neighbor in image resampling, when speed is not an issue. Images resampled with bicubic interpolation are smoother and have fewer interpolation artifacts.



Figure 1: Preferences

When you scale with the different options the differences are hardly noticeable.



Figure 2: Scaling with different options

2. Interpolation command

With the Interpolation command you have a quick access to interpolation options in the Fireworks Preferences. You may download it at the end of the article.

3. Downscaling and upscaling

Downscaling and upscaling a vector object is not a problem it will not result in any quality loss, as it will remain a vector but it is far from different for bitmaps.

For example, open a 500x500 bitmap in Fireworks, resize to 100x100, then resize to 500x500 again. Image becomes pixelated, quality is lost!



Figure 3: Downscaling and upscaling

4. Create a symbol

The only way to overcome this pixelation problem is to create a symbol. Open a 500x500 bitmap in Fireworks, select the bitmap, right-clic, select F8 (Convert to symbol) and convert it to a graphic symbol. Now, resize the graphic symbol to 100x100 , then resize it to 500x500 again. Result: the image is not pixelated! After you have converted your image to a symbol you can freely resize it without the image becoming pixelated.



Figure 4: Create a symbol

If you open a large 3000x2000 bitmap in Fireworks then convert it to symbol then downscale it to 300x200 it will result in a huge file size even if you downscale it. That is because inside the symbol the file has not changed and is still a 3000x2000 file with the same file size. On the other hand, if you want a much smaller file size, you would rather resized it first to say, 600x400, before converting it to a symbol.

5. Conclusion

This tip can be used by everybody.

6. Download Instructions
1. Unzip the file
2. Double click the mxp file.

Where to go from here

• Fireworks CS4 Help

Credit

Thank to Michel Bozgounov for his tips.