This Property inspector allows you to set properties for an image. If you do not see all of the image properties as shown below, click the expander arrow in the lower right corner

To set image properties:

Set any of the following options:

Use the text field below the thumbnail image to set a name.

W and H are the width and height of the image, in pixels. Dreamweaver automatically updates these fields with the image’s original dimensions when you insert an image in a page.

If you set W and H values that do not correspond to the actual width and height of the image, the image may not display properly in a browser. (To restore the original values, click the W and H field labels.)

Note: You can change these values to scale the display size of this instance of the image, but this does not reduce download time, because the browser downloads all image data before scaling the image. To reduce download time and to ensure that all instances of an image appear at the same size, use an image-editing application to scale images.

Src specifies the source file for the image. Click the folder icon to browse to the source file, or type the path.

Link specifies a hyperlink for the image. Click the folder icon to browse to a document on your site, or manually type the URL. For information about creating links, see Creating links.

Align aligns an image and text on the same line. See Aligning an image.

Alt specifies alternative text that appears in place of the image for text-only browsers or for browsers that have been set to download images manually. For visually impaired users who use speech synthesizers with text-only browsers, the text is spoken out loud. In some browsers, this text also appears when the pointer is over the image.

Map Name and the Hotspot tools allow you to label and create a client-side image map.

V Space and H Space add space, in pixels, along the sides of the image. V Space adds space along the top and bottom of an image. H Space adds space along the left and right of an image.

Target specifies the frame or window in which the linked page should load. (This option is not available when the image isn’t linked to another file.) The names of all the frames in the current frameset appear in the Target list. You can also choose from the following reserved target names:

_blank loads the linked file into a new, unnamed browser window.

_parent loads the linked file into the parent frameset or window of the frame that contains the link. If the frame containing the link is not nested, the linked file loads into the full browser window.

_self loads the linked file into the same frame or window as the link. This target is the default, so you usually don’t need to specify it.

_top loads the linked file into the full browser window, thereby removing all frames.

Low Src specifies the image that should load before the main image. Many designers use a 2-bit (black and white) version of the main image because it loads quickly and gives visitors an idea of what they’re waiting to see.

Border is the width, in pixels, of the image’s border. The default is no border.

Edit launches the image editor you specified in External Editors preferences and opens the selected image. For information about setting an external image editor, see Using an external image editor.

Reset Size resets the W and H values to the original size of the image.

Source: Dreamweaver MX Help