Bitmaps Overview

A bitmap is a picture composed, of small 'dots' called pixels. Bitmaps are created using a variety of programs such as Microsoft Paintbrush, CorelPaint and Photoshop or taken from scanners or CD. You can import and export all common bitmap formats and provides a variety of methods of manipulating and using them.

Importing and Exporting Bitmaps

You can import and export a very large range of different types of bitmaps. For a full list, see the List of Supported File Formats. Xara LX supports many features which make it ideal for creating bitmaps for publication on the Internet.

2 ways to save a bitmap:

1) Right click on the bitmap in the bitmap gallery and select Save. This saves the whole bitmap at the same pixel size as the original. You can select to save in a wide variety of bitmap types. If you select JPEG it will re-compress the JPEG using the quality value as last set on the Export JPEG dialog.

2) Select the bitmap on the page and Select File -> Export (Ctrl+Shift+E) This will save the bitmap at the dimensions shown on screen and NOT the original size. So if your 2000 pixel JPEG is scaled down to be to be 288 pixels on screen (i.e. 3 inches), it will be saved as 288 pixels wide, by default. In fact you get control in the Export dialog over size and a lot of other variables. In the Export options dialog on the bitmap size tab you can adjust the width and height (in pixels) or the resolution. So if you want to save it as 1024 pixels wide, just enter the 1024 width. If you select the 1:1 button you can see the 100% actual size the image will be saved at, to check.

The Options tab allow you to alter the JPEG compression and you get a small preview of this in the display.

Re-sizing high-resolution bitmaps

Both Export (Ctrl+Shift+E) and Create Bitmap Copy (Ctrl+Shift+C) do not use the screen version, but re-create a higher quality (bicubic sampled) version for export. This is especially noticeable when scaling very large bitmaps down. The screen display uses simple smoothing and shows aliasing artefacts when scaled much less than half size. The exported or re-created version is much higher quality.

So if you want to re-size a high-resolution bitmap to be a lower size/resolution, at the highest possible quality, the recommended way is simply to resize it on screen to the required dimensions and either Export or Create Bitmap Copy.

And this shows best when doing screen grabs.

How to do a scaled-down screen grab

• Press the Print Screen key, usually more useful, press Alt+Print Screen keys to grab the current window.

• Ctrl+V and select 'bitmap' to paste the grabbed image into Xara

• Resize to the required size

• Export or Create Bitmap Copy (Shift+Ctrl+C) to display the Options dialog.

If you want to paste the result into other applications, it good to reduce the colors to keep the file as small as possible

• Select Color Depth drop down to be 256 colors, or even 16 colors

• Unselect the glass transparency icon - no point is having transparency in the bitmap. Click Save, or Create

• If you created a bitmap copy on screen, select this and Ctrl+C to copy it to the system clipboard.

• You can now paste this into just about any other application

So it takes a few seconds to create a high quality, small size, re-scaled screen grab to paste into any application.

You'll be surprised how good 16-color screen grabs can be and if saving as PNG or pasting into other applications this can make a very substantial difference to the file size.

Masking Bitmaps

You can remove unwanted areas of bitmaps very easily. See Masking a bitmap for more details.

Using Bitmaps As Fills

Any bitmap can be used to fill other objects. For example, you can fill shapes or text with a tessellating bitmap. This is called a bitmap fill
. For details on how to apply a bitmap fill to an object, see Applying bitmap fills.

Making Bitmaps Transparent

You can make any object transparent and this includes bitmaps. You can use any of the different shapes of transparency (flat, linear, circular and so on).

This picture consists of two bitmaps. The top bitmap has a linear transparency allowing you to see the other bitmap through it.

Using Bitmaps to Set Transparency

Xara LX includes a wide range of shapes of transparency, one of which is bitmap transparency
. If you apply a bitmap transparency to an object, its transparency is set by the brightness of the pixels in the bitmap.

The top shape in this example is a black rectangle with a bitmap transparency applied to it. Note how the amount of the image you can see underneath is set by the level of gray of the bitmap used for the transparency. For more details, see Applying bitmap transparency.

Movies—click below (click here for more movies)

Using bitmap fills

Using the bitmap tracer

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Related Topics

Bitmap effects

Bitmap Gallery

Fill Gallery