Vectors vs. Bitmaps

Computers store picture information in two different ways – using vector or bitmap file formats.

When a bitmap file type is used, the computer divides the picture into a grid. You can see the squares on the grid if you zoom in very close to a bitmap image. These squares are known as pixels.

Bitmaps are good file types to use when you are working with very complex textures or photographs. However, the file sizes can be large and if your image is scanned or created with a low resolution to keep the file size down, you may get a pixilated image in which you can see the square outlines of your pixels.

Vector images, on the other hand, have very small file sizes. The computer uses geometry and mathematics to store the picture information.

Vector files are resolution independent. If you zoom in close to them, the outlines will remain crisp and perfect. They are good to use for graphics with blocks of color and gradients, but not so useful for complex textures.

Work produced in vector programs like Flash tend to have a particular ‘look’ about them. Get some texture into those clean looking vectors with the careful use of bitmaps.

Still Image File Types You can Import

Although Flash is a fantastic program to use for drawing, you may wish to bring in photographs or other types of images that you have created in software outside Flash. There are many options available to you.

There now follows a list of the main still image file formats that you can import into Flash and some information about them. Check out the Flash Help menu if you are interested in importing more specialized file types.

To Import a Still Image into Flash

  1    Make sure the layer you want the image to be on is active.

  2    Select File > Import to Stage.

  3    You can also import numbered sequences of still images. If you do this, the stills will be brought in as successive frames of the layer that is active.

  4    Your image file can be accessed in the Library. If you go to the Library Options menu and choose Edit, this command launches Fireworks or another image editing software package if you don't have Fireworks on your machine. There is more about libraries in the next chapter.

Importing Images with Areas of Transparency

If you define an area of transparency using your image editing software, you maintain this when you import the file into Flash. Here's how to do this using Photoshop:

  1    In Photoshop, open up the file that you want to create transparency in.

  2    Go to Image > Image Size and make a note of the pixel dimensions.

  3    Choose File > New to start a new file and make sure you have selected Background > Transparent and Mode > RGB.

  4    The Resolution will always be 72 pixels/inch for screen based work like that for output to video or the Internet, as this is the resolution of the screen itself.

  5    Make this new file exactly the same size as the image that you first imported.

  6    Using the Move tool (shortcut – V), drag and drop the image onto the new blank file you created. If you hold down the SHIFT key while you drag and drop, the image will be placed in the center of the new file.

  7    Close the original file.

  8    Using any combination of selection tools, select the area you want to be transparent and then delete it.

  9    File > Save and choose PNG as your file format, then Interlace > None.

 10   Import into Flash as above and your image should have a hole in it!

Tracing Bitmaps

If you want to reduce the file size of a bitmap image that you have brought into Flash, you can convert it into a vector graphic.

Another reason for doing this would be to change a photograph into a more stylized vector image.

  1    Import the bitmap image file that you want to convert in Flash.

  2    Make sure it's selected and then choose Modify > Bitmap > Trace Bitmap.

  3    The options that are available are as follows:

• Color threshold = sensitivity of color selection
• Minimum area = the number of surrounding pixels to consider as one block
• Curve fit = how smoothly the outlines will be drawn
• Corner fit = how sharply the edges will be retained.

  4    The following settings will give you the best possible settings, however this might take some time to process depending on the capabilities of your computer.

  5    Experiment with different settings until you achieve the style that you want. Lower quality settings will take much less time to process.

  6    When you have first completed this process, all the bits of traced bitmap will be selected and it will appear to be grayed out.

  7    Click away from the image onto a blank part of the Stage to deselect it.

  8    You will now be able to adjust individual parts of the image just as if you had created the image in Flash with the Paint tool.

Painting with Bitmaps

It is possible to import textures and paint with them in Flash. This can be especially effective when used with small tileable textures like snakeskin or bricks.

  1    Import the bitmap you want to use, make sure it is selected and Modify > Break apart.

  2    Select the Eyedropper Tool and click on the broken apart bitmap.

  3    This loads the image into memory and you can now paint with it using the Paint tool. It will also fill any shape that you create with the Pen tool or the Oval or Rectangle tools.

  4    The Fill Transform tool can be used to alter the scale, rotation and skew of the tiled image.

  5    Finally, you can also select Bitmap as a Fill option in the Color Mixer panel. The bitmap will be tiled to fit the image and you can adjust it as above.

Finally, copyright issues don't just apply to music, but also to images. It may be tempting to use other people's images that you have found in books, magazines or on the web, but this is someone else's intellectual property. Ultimately, it is much more rewarding to be original and create your own.