MACROMEDIA DIRECTOR MX-USING DIRECTOR MX, Руководство пользователя

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Chapter 7 204
A bitmap typically requires more RAM and disk space than a comparable vector shape. If not
compressed, bitmaps take longer than vector shapes to download from the Internet. Fortunately,
Director offers compression control to reduce the size of bitmaps in movies that you package to
play on the web. For more information about bitmap compression, see “Compressing bitmaps”
on page 239.
For more information about vector shapes, see Chapter 8, “Vector Shapes,” on page 245.
You can create bitmaps in the Paint window or import them from any of the popular image
editors in most of the popular formats, including GIF and JPEG. Director can also import
bitmaps with alpha channel (transparency) data and animated GIFs. The Paint window includes a
variety of tools for editing and applying effects to bitmaps.
About importing bitmaps
Importing bitmaps is similar to importing other types of media. If you import a bitmap with a
color palette or depth different from that of the current movie, the Image Options dialog box
appears. You must choose to import the bitmap at its original color depth or at the current system
color depth. If you are importing an 8-bit image, you have the choice of importing the image’s
color palette or remapping the image to a palette that is already in Director. See“Choosing import
image options” on page 150.
Director can import images with alpha channel (transparency) effects, which are 32 bits. If you
reduce the image to a lower color depth, Director removes all the alpha channel data.
When importing bitmaps, you should always consider that they will display on the screen at your
monitor’s resolution (generally 72 to 96 dots per inch). Higher-resolution images that you place
on the Stage in Director might appear much larger than you expect. Other applications,
particularly those focused on creating images for print, let you work on the screen with high-
resolution images at reduced sizes. Within Director, you can scale high-resolution images to the
right size, but this might reduce the quality of the image. Also, high-resolution images use extra
memory and storage space, even after they’ve been scaled.
If you are working with a high-resolution image, convert it to between 72 and 96 dots per inch
with your image-editing program before you import it into Director.
Director supports JPEG compression at runtime for internal cast members that are imported
through the Standard or Include Original Data for Editing import options. A JPEG file that is
imported with either of these options contains both the original compressed bits and
decompressed bits. After it’s imported, the JPEG file decompresses in the authoring environment.
The cast member size displays the member’s size in RAM after it’s decompressed. The amount of
RAM required to display a JPEG file is larger than its size on disk, so don’t be surprised that your
cast member size is larger than its original size on disk in the Cast Properties window.
Director takes advantage of compressed JPEG data at runtime. The original compressed data bits
are saved in a Macromedia Shockwave movie or a projector (if the Shockwave compression option
is on). If you edit the member within Director in the Paint window, the compressed data will be
lost. An alert appears before the data is overwritten.
If the Shockwave compression option is on, Director also compresses bitmaps into the JPEG
format. For more information about bitmap compression, see “Compressing bitmaps”
on page 239.