Impress Guide

Chapter 4
Adding and Formatting Pictures

Introduction

Pictures are often used in presentations as they can convey a large amount of information more quickly than the written word. They can also give the presentation a professional look by adding a company logo. You may also want to use Impress to create a presentation consisting only of pictures, such as a slideshow of holiday snapshots to share with friends.

This chapter describes how to insert and format pictures.

Inserting pictures

This section describes several ways to insert a picture from an external source into the presentation. Once the picture has been inserted, it can be formatted extensively as explained later in this chapter.

Inserting a picture from a file

Inserting a picture from a file is quick and easy. First choose the slide layout, as described in Chapter 1, Introducing Impress. Most layouts include an set of icons for inserting objects, but you can insert a picture into any slide.

Whether you are using an AutoLayout for the placement of the picture, or you are just inserting a picture, follow these steps:

1. Click on the Insert Picture icon or choose Insert > Picture > From file from the menu bar.

2. In the Insert picture dialog box, navigate to the directory containing the desired picture.

3. Select the file. LibreOffice recognizes a large number of image types. If the Preview option (in the lower left-hand area) is selected, a thumbnail of the selected file will be displayed in the preview pane on the right (not shown below).

4. Click Open to place the picture on the current (selected) slide. The picture is now displayed on the slide with green resizing handles around it.

Notice in the Insert picture dialog box the two options Link and Preview. Their position is determined by the operating system, but they are normally in the bottom-left part of the dialog box.

Select the Link option to insert the picture as a link to the file rather than embedding the file itself. In general it is preferable to embed images so that the presentation can be copied to other computers; however, on some occasions it makes sense to link the image rather than embed it. These include:

• When the image file is quite large (linking rather than embedding will dramatically reduce the size of the presentation file)

• When the same image file is used in many presentations (for example when using the same background image for all the presentations created)

• When the linked file will be available when loading the presentation (for example if the presentation is a slide show of holiday pictures)

Inserting a picture from a scanner

Inserting an image from a scanner is normally fairly straightforward. Make sure that the scanner is supported by the SANE system if you are running the Linux (or other UNIX-like) operating system, or TWAIN if you are using a Windows version, and that it is already configured on the machine on which LibreOffice is running. In case more than one scanner or equivalent devices are present, select the source from Insert > Picture > Scan > Select Source.

To insert an image from the scanner:

1. Prepare the image in the scanner and make sure that the scanner is ready.

2. Choose Insert > Picture > Scan > Request.

3. The rest of the procedure depends on the scanner driver and interface. You will normally be required to specify the resolution, a scan window and other parameters. Consult the scanner’s documentation for more information.

4. When the image is ready, Impress places it in the slide. At this point it can be edited as any other image.

Inserting a picture from the Gallery

The Gallery contains a collection of images that you can use in a presentation. You can also add your own images to the Gallery, making it an essential tool for creating presentations quickly and with a consistent look. The Gallery is available in all components of LibreOffice. For an introduction to the Gallery, see Chapter 11, Graphics, the Gallery, and Fontwork, in the Getting Started guide.

Choose Tools > Gallery or click the Gallery icon on the Drawing toolbar.

The Gallery displays categories of themes with images stored under each category. Select a theme from the left pane and then scroll as necessary through the right pane to find a suitable image. Click on the image and drag it onto the workspace. Figure 3 shows an example.

At this point the image will be in your slide, but may not be of a satisfactory size; if necessary, resize it as described in “Resizing a picture” on page 9.

Positioning the Gallery

To expand the Gallery, position the pointer over the line that divides it from the top of the workspace. When the pointer changes to parallel lines with arrows, click and drag downward. The workspace will resize in response.

By default, the Gallery is docked above the Impress workspace. To undock it , hold down the Control key and double-click on the upper part of the Gallery next to the View icons. Double-click in the same area to dock it again (restore it to its position over the workspace).

When the Gallery is docked, to hide it and view the full Impress workspace, click the Hide/Show button in the middle of the thin bar separating the Gallery from the workspace (see Figure 4). The Hide/Show button lets you keep the Gallery open for quick access while you create your slide show, yet out of the way when you need it to be.

Managing the Gallery themes

Graphics in the Gallery are grouped by themes, such as Bullets, Rulers, and 3D Effects. The box on the left of the gallery window lists the available themes. Click on a theme to see its graphics displayed in the Gallery window.

The default themes are locked; no items can be added or deleted from these themes. The locked themes are easily recognizable by right-clicking on them; the only available option in the pop-up menu is Properties.

In a default installation, only the My themes theme is customizable: you can add your own graphics to this gallery or add new themes as explained on page 8.

Adding images to the Gallery

You can add new images to themes which you created, or to themes like My themes that can be edited:

1. Right-click on the theme name in the list of themes and choose Properties from the pop-up menu.

2. Click the Files tab, if necessary.

3. Click Add.

4. Select a file and click Open. The image is added to the theme.

Deleting images from the Gallery

To delete an image from a theme:

1. Right-click on the image in the Gallery window.

2. Choose Delete from the pop-up menu. A message appears, asking if you want to delete this object.

3. Click Yes.

All the images in a gallery are actually linked files. From time to time it is beneficial to update the gallery theme to make sure that all the files are still there. To do so, right-click on the theme where you added at least one file and then select Update from the pop-up menu.

Adding a new theme to the Gallery

1. Click the New Theme button above the list of themes.

2. Click the General tab and type a name for the new theme.

3. Click the Files tab (Figure 5).

4. Click Find Files. The Select Path dialog box opens. Navigate to the folder that contains the image files for the new theme and click Select.

5. Back on the Files tab, either click on Add All to install all of the files in the selected folder, or use File Type and/or select one or more files from the displayed list, and click on Add to install a selection of files to the new theme.

6. Click OK when finished.

7. The new theme will now be displayed on the list of themes in the Gallery, under the name New Theme. You will have to rename it manually by right-clicking the theme name and selecting Rename.

Formatting pictures

This section discusses the formatting of pictures inserted with one of the methods explained in “Inserting pictures” on page 4.

Moving a picture

1. Click the picture, if necessary, to show the green resizing handles.

2. Move the pointer over the picture until the pointer changes shape. On most operating systems, the cursor associated with moving objects is a four headed arrow, but it may also be a hand or some other symbol.

3. Click and drag the picture to the desired position.

4. Release the mouse button.

For a more accurate placement of the picture, use the Position and Size dialog box described in Chapter 6, Formatting Graphic Objects.

Resizing a picture

1. Click the picture to show the green resizing handles.

2. Position the pointer over one of the green resizing handles. The pointer changes shape giving a graphical representation of the direction of the resizing.

3. Click and drag to resize the picture.

4. Release the mouse button when satisfied with the new size.

The corner handles resize both the width and the height of the graphic object simultaneously, while the other four handles only resize one dimension at a time.

For more accurate resizing of the graphic object, use the Position and Size dialog box described in Chapter 6, Formatting Graphic Objects.

Rotating a picture

As with the position of the image on the page, rotation of a picture can be done manually or using a dedicated dialog box. The Rotation dialog box is described in Chapter 6, Formatting Graphic Objects. To rotate a picture manually, do as follows:

1. Select the picture if necessary so that the green handles around it show.

2. Click the Rotate button on the Drawing toolbar. This toolbar is usually located at the bottom the screen, but it can be undocked and used as a floating toolbar. If the toolbar is not showing, select View > Toolbars > Drawing. The Drawing toolbar is discussed in detail in Chapter 5, Managing Graphic Objects.

At this stage a black crosshair with a circle appears in the middle of the picture: this represents the pivot point for the rotation. Normally the center of the picture will be just fine, but on some occasions you may wish to rotate around a corner or even around a point outside the picture; to do this, click on the crosshair and drag it to the desired position before applying the rotation, as shown in Figure 6.

3. Eight red circular handles replace the green square handles, as shown in Figure 6. Move the mouse over one of the corner handles and the mouse cursor shape will change. Click the mouse and move in the direction in which you want to rotate the picture.

4. When satisfied, release the mouse button.

To restrict the rotation angles to multiples of 15 degrees, press the Shift key while rotating the graphic. This is very handy to rotate pictures of right angles, for example from portrait to landscape or vice versa.

Formatting using the Picture toolbar

When a picture is selected, the Picture toolbar becomes available. This toolbar provides a number of formatting options which are described in this section. If the picture toolbar does not appear when an image is selected, display it by selecting View > Toolbars > Picture from the menu bar.

Applying filters

Figure 8: The graphic filters available in Impress

Use the icon on the toolbar to apply various filters to the selected picture. The best way to judge if a filter works for your picture is to try it. To apply a filter:

1. Select the image so that the green handles around it are displayed.

2. Click on the icon in the Picture toolbar. The toolbar will expand to show the icons in Figure 8.

3. Select the filter you wish to apply. To show the name of the filter, hover the mouse pointer over the icon and wait for the tooltip to appear.

If you are not satisfied with the effect obtained or you want to try a different one, before doing anything else click the Undo button or select Edit > Undo: Bitmap Graphic Filter from the menu bar or press Control+Z.

Table 1 describes briefly each of the available graphic filters and their effects. See the Draw Guide for examples of the effects.

Table 1: Graphic filters and their effects

Changing the graphics mode

Use the graphics mode drop-down list in the Picture toolbar to change the mode of the image. Choose between:

• Default: no changes to the graphic object.

• Grayscale: the image is converted to scales of gray.

• Black/White: each pixel of the image is converted to black or white depending on the brightness value.

• Watermark: adjusts the brightness of the image making it suitable to be used as a watermark. For more information on inserting watermarks in the presentation, refer to Chapter 2, Slide Masters.

Figure 9: The color adjustment dialog box

Clicking the color adjustment button on the Picture toolbar opens the color adjustment dialog box.

Use this dialog box to modify the individual color components of the image (red, green, blue) as well as the brightness, contrast, and gamma of the image. If the result is not satisfactory, press Control+Z to restore the default values.

Increasing the gamma value of a picture makes it more suitable to be used as a background or watermark as it will interfere less with a dark text.

Setting the object transparency

Modify the percentage value in the Transparency box on the Picture toolbar to make the image more transparent. Note that this is different from the transparency settings for a line or a shape (described in Chapter 5). As with the gamma value, increasing the transparency of a picture makes the picture blend more smoothly in the background, making the overlay text easier to read.

Adjusting the line, area and shadow settings

These settings are not very commonly used for images, with the exception of the shadow setting, which applies a shadow to the image.

Cropping pictures

Impress provides two ways to crop a picture: interactively or using a dialog box. The interactive method is easier to use, but the dialog box provides more precise control. You can use both methods: first cropping interactively, then using the dialog box to fine tune the result.

To crop a selected picture interactively, click the Crop icon on the Picture toolbar (Figure 7). A set of crop marks appears around the picture (see Figure 10).

When you place the cursor over any of the crop marks, the cursor changes shape. Drag the mark to crop the picture. Click outside the picture to deactivate cropping mode.

Press the Shift button while working on the crop marks to produce the following effects:

• For a corner mark, the two sides of the picture forming the corner are cropped proportionally with the picture anchored to the opposite corner mark.

• For a side mark, both dimensions are changed proportionally with the image anchored to the opposite side mark.

The interactive crop mode operates in Keep Scale mode (see below).

To crop using the dialog box, right-click a selected picture and choose Crop Picture (or choose Format > Crop Picture from the menu bar).

The Crop dialog box (Error: Reference source not found) has the following options:

• Keep scale / Keep image size buttons: when Keep scale is selected (default), cropping the image does not alter the scale of the picture. When Keep image size is selected, cropping produces enlargement (for positive cropping values), shrinking (for negative cropping values), or distortion of the image so that the image size remains constant.

• Left, Right, Top, and Bottom: the function of these boxes changes according to the choice made between Keep scale and Keep image size. In both cases, when a value is entered in one of these boxes, the image is cropped by that amount. For example, a value of 3cm in the Left box will cut 3cm from the left side of the picture.

  When Keep scale is selected, the size of the image also changes, so in this example the width will be reduced by 3 cm. If Keep image size is selected instead, the remaining part of the image is enlarged (positive values for cropping) or shrunk (negative values for cropping) so that the width and height of the image remains unchanged.

Note that the Width and Height fields change as you enter the values when in this mode. Use the thumbnail next to these fields to determine the correct amount by which to crop.

• Scale Width and Height: specify in percentages the scaling of the picture. The size of the image changes accordingly.

• Image size: specify the size of the image in your preferred unit of measurement. The image enlarges or shrinks accordingly.

• Original size: when clicked, restores the original image size.

Deleting a picture

1. Click on the picture, if necessary, to show the green resizing handles.

2. Press Delete.

Creating an image map

An image map defines areas of the image (called hotspots) associated with a URL (a web address or a file on the computer). Hotspots are the graphic equivalent of text hyperlinks. Clicking on a hotspot causes Impress to open the linked page in the appropriate program (for example, the default browser for an HTML page; LibreOffice Writer for a .ODT file; a PDF viewer for a PDF file). You can create hotspots of various shapes, and include several hotspots in the same image.

To use the image map tool:

1. Select the picture where the hotspots will be defined.

2. Choose Edit > ImageMap from the menu bar. The ImageMap Editor dialog box opens. The main part of the dialog box shows the image on which the hotspots will be defined. On this image an active hotspot is indicated by a white shading, while an inactive hotspot is identified by a red border but no shading.

3. Use the tools and fields in the dialog box to define the hotspots and links necessary.

4. Click the Apply icon to apply the settings.

5. When done, click the Save icon to save the imagemap to a file, then click the X in the upper right corner to close the dialog box.

The top part of the dialog box contains the following tools:

• Apply button: click this button to apply the changes.

• Load, Save, and Select icons.

• Tools for drawing a hotspot shape: these tools work in exactly the same way as the corresponding tools in the Drawing toolbar (described in Chapter 5).

• Edit, Move, Insert, Delete Points: advanced editing tools to manipulate the shape of a polygon hotspot. Select the Edit Points tool to activate the other tools.

• Active icon: toggles the status of the hotspot activating a selected hotspot or deactivating it if active.

• Macro: associates a macro with the hotspot instead of a hyperlink.

• Properties: sets the hyperlink properties and adds the Name attribute to the hyperlink.

Below the toolbar, specify for the selected hotspot:

• Address: the address pointed by the hyperlink. You can also point to an anchor in a document such as a specific slide number; to do this, write the address in this format: file:///<path>/document_name#anchor_name

• Text: enter the text that will be displayed when the mouse is moved over the hotspot.

• Frame: where the target of the hyperlink will open: pick among _blank (opens in a new browser window), _self (opens in the active browser window), _top or _parent.