LXF110.tut_gimp.pdf

Gimp Open source image-editing

software you can get your teeth into

Gimp: Creative

Gimp can do more with text than you might think, as our graphics guru

Michael J Hammel demonstrates with his two beautiful assistants.

images. Most desktop users will prefer to work with Gimp

when dealing with their digital photographs but might

choose other tools like Inkscape or Scribus when working with

text. But don’t be fooled: Gimp does a great job with text effects,

and in ways that most people might think can only be done with

vector applications.

This month I’m going to walk you through a little trick with text

that my wife found in a design magazine. In that tutorial the

process was handled using InDesign. InDesign, for those who don’t

use it, is a vector layout tool. It does clever things with text using

boxes to align and block objects within the layout. This particular

effect, which you can see in the cover image for this tutorial, turns

out to be even easier in Gimp than described in the original

InDesign tutorial.

Projects like this have important periphery components

beyond just the text. This design requires a source image that has

sufficient colour and contrast. Without colour and contrast the

shapes within the image won’t be recognisable through the text.

The project also requires a suitable font. The font needs to be

thick and should not use any serifs. Serif fonts will make the final

image appear cluttered, and in most cases won’t allow as much

detail from the source image to show through, even when bold

versions of the serif font are used. It can also make it difficult to

recognise the text from the image.

The goal of this project is to map an image on to text but keep

the original image recognisable. Gimp’s text features make the

actual design something that can be done in a few minutes and

with a limited set of steps. So before we dive into that, let’s take a

look at some of these periphery issues involved when working on

similar designs.

Select a stock image

To start the project, visit one of the many low-cost stock image

sites and search for a human portrait. The picture we want needs

to include two important features. The first is a solid coloured

background. A cluttered background will make it harder to identify

the subject of the image when we apply our text effect.

The second important feature is a fair amount of colour

contrast. An all-black image would work just fine, but would end

up being nothing more than shadow-filled text. For this project I

selected a woman in a black dress with enough skin tones to

provide some colour contrast. We’ll add to that contrast with a soft

vignette a little later.

When selecting stock images you should be aware of licensing

issues. If the image is of inanimate objects, you’re generally safe. If

the image shows a recognisable face, then you’ll need to make

sure the publisher of the photo (whoever uploaded it) has

obtained a model release from the subject of the image. Without

the model release, you can’t use the image in published work.

Our

expert

Michael J

Hammel is a

contributor to the

Gimp project and

the author of three

books on the

subject, including

his latest, The

Artist’s Guide to

Gimp Effects.

Last month In last month’s column, author Michael J. Hammel talked about using

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G imp is first and foremost a tool for working with raster

Gimp Tutorial

design

All three text

samples are set

to 18 pixels with

-5 pixel line

spacing and -2

pixel tracking.

used. In this tutorial I’m using the bold version of the Tahoma font

but any sans font, probably using the bold face, will suffice.

The first Gimp-specific tip for this tutorial is related to the Text

tool options. Select the Text tool and then open the Tool Options

dialog (Dialogs > Tool Options). Just above the button labelled ‘Text

Along Path’ there are three options. These options are for, top to

bottom, Indent, Line Spacing and Tracking. We won’t be using the

indent option but we do want to use the other two. We want the

value in Line Spacing made smaller (to negative values) so that the

lines of text will be as close as possible without overlapping.

Tracking sets the space between letters. This is similar to

kerning but is not exactly identical. Again, the technical

explanation is not important here. We just want to reduce this

setting (also to negative numbers) to reduce the space between

letters – the closer the better.

Adding a vignette

The first thing we want is to add a soft vignette. This will make the

final image a little more colourful while keeping the woman’s

shape recognisable. To do this, we add a transparent layer above

the main layer (Layer > New) and name this new layer Vignette.

Select the Elliptical selection tool from the Toolbox and in the

image window draw an oval selection around the girl. Feather the

selection (Select > Feather) by 100 pixels. Choose a warm colour

for the foreground colour by clicking on the foreground colour box

in the Toolbox. I’m using RGB values of 231/127/35 for this tutorial.

We now need to add a radial gradient inside the circle.

Choose the Gradient tool from the Toolbox. In the Tool Options

dialog (Dialogs > Tool Options) set the Gradient to ‘FG To

Transparent’ and the Shape to ‘Radial. In the image, click and drag

from the middle of the selection to just past the top of the

selection. Set the vignette layer’s mode to Multiply.

At this point I add a little noise to the gradient for an artistic

effect, but this step is optional. To add the noise, select Filters >

Noise > HSV Noise and set the Holdness to 2, the Saturations to

255 and the Value to 255. The default setting for Hue (which

Quick

tip

Scan multiple

stock photo archives,

such as

BigStockPhoto.com,

iStockPhoto.com

and Stock.xchng

( www.sxc.hu ).

The seated woman has a low contrast between background,

skin and dress; the dancing woman is a much better image.

Fortunately, most stock image sites will either require the

photographer to submit the model release or let you know if no

model release is available.

Working with comps

So you’ve scanned a few hundred images and found a few that

might work. How can you tell how well they’ll work? The answer

comes from working with comps. A comp is a small version of a

stock image that typically contains a watermark. Most of the stock

image sites will allow you to download a comp or, if they don’t

explicitly offer them, will have large enough sample versions for

viewing that you can download without paying for them.

Comps are for experimenting. They’re often too small to use in

final projects and would be inappropriate considering the

watermark. But they’re useful for testing an idea. The testing for

this project requires only that we use a smaller font size that what

we’ll use in the final project. I used comps of several images before

selecting the final image of the woman in the black dress. If the

comps are too small you can double the image size for the

experiment even if that pixellates the image.

This effect works best with thick, straight-edged fonts. Script

fonts don’t show the image very well, even when a bold face is

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Tutorial Gimp

Choose a warn colour for the vignette, to add some extra contrast to the final

image – this really helps in the white areas of the source photograph.

Any noise you add to the vignette might not be visible in the

finished image (this depends on the font thickness).

Quick

tip

should be 3) should not be changed. Then apply this to the

Vignette by clicking on the OK button. The noise will only be applied

within the selection and only to coloured pixels – not transparent

ones. You can clear the selection now (Select > None) and merge

the Vignette and background layers (Image > Flatten Image).

Adding a text layer

The crux of this tutorial is to use text as a mask over the image. To

do this, start by resetting the default colours in the Toolbox (the

small black and white boxes below and to the left of the larger

black and white boxes). Then create a text layer filled with random

words. Choose the Text tool from the Toolbox and click in the

image. This will open up the Text Editor window. In this window,

paste a large amount of text.

So what text should you use? I first copied 1,500 words from

the Lorum Ipsum generator into a 100-character-wide text

terminal. I then used the Vi editor to remove all line breaks (Shift+J

on each line, making one long line) and mapped the text to fit the

window with line breaks (In Vi: G+Q+J). If this isn’t long enough,

join all the lines again, copy and past below it to extend the text.

The select and copy this text into the Text Editor window. Using a

100-character-wide terminal allowed me to create text that would

be wide enough to cover the image but still include line breaks

which Gimp needs to block the text.

Pasting the text will update the image window immediately. You

can now close the Text Editor window. In the Tool Options dialog

you’re ready to set the font, size, line spacing and tracking as

mentioned previously. Choose the font and size before changing

the spacing and tracking. Remember I used Tahoma Bold, which

you can find in the Corefonts project on SourceForge. You’ll also

want the text in black so you can see it in the image window.

Set the line spacing to -5 and the tracking to -3. This is

sufficient to push the letters up against each other horizontally

and vertically without overlapping, at least for this specific font

and size.

Vignettes are an

easy way to add

colour to high-

contrast, low-

colour photos.

Getting the source images

The source images from this tutorial

were purchased from BigStockPhoto

for $2 each. The image IDs are

Pretty Dancing Woman (black

dress): 1716725 (size: 1066 x 1600)

Sunflower Girl: 2861058

(size: 900 x 900)

Pixel amounts specified in the

tutorial are based on these source

image sizes.

Cows do not require a model release.

Initially the text will not be aligned with the rest of the image,

but we’ll fix that with the Align Tool.

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Gimp Tutorial

The text layer is much larger than the canvas window (which

has been zoomed out to show the text layer boundaries).

Keeping multiple versions of the text layer and masks lets you compare the masks

and return to the version that looks best without having to recreate it later.

Now align the text layer with the Align tool (it looks like a box

with arrows pointing away from all four sides). Click on the image

window over the visible text. This adds the text layer to the set of

layers to be aligned. Hold the Shift key down and click on the

background layer (the woman in the dress) in the image window

to add it to the layers to be aligned. Now the text layer and the

background layer are included in the set of layers to be aligned.

You can tell this is the case by looking for small black boxes at the

corners of each layer that will be included in the alignment.

In Layers dialog make sure the background layer is the active

layer, and in the Tool Options dialog, set the ‘Relative To:’ menu to

Active Layer. In the Tool Options dialog there are two sets of six

buttons that look identical. The first set are for alignment (the

other set is for distribution, which we aren’t concerned with here).

Click on the horizontal and vertical alignment buttons, which each

look like two arrows pointing to a central line, which is either

horizontal or vertical. Now the text is aligned over the image.

Resize the canvas to fit the text layer, zoom out and shrink-wrap

the window (Ctrl+E) around the canvas.

Create a mask layer

Now we’re ready to create our mask. We start this process by

adding a White layer to the image (Layer > New, set Fill Type to

White). Drag this layer into the Layers dialog below the

background layer. At this point you should drag the text layer

below the background layer too.

Click on the Text layer in the Layers dialog to make it the active

layer, then create a selection of the text (Layer > Text to Selection

> Text to Selection) and invert the selection (Select > Invert). This

provides a selection of everything except the text. Click on the

White layer you just added to make it active. Create a copy from

the selection (Edit > Copy) and then paste the copy (Edit > Paste).

This creates a Floating Selection layer in the Layers dialog that

must be converted to a new layer manually (Layer > New).

What you’ve done here is to paste a white layer with the text

stamped out of it over the source image. Where the text was

stamped out, the source image shows. Turn off the visibility of the

Text layer by clicking on the Eye icon to the left of the layer

thumbnail in the Layers dialog.

Click on the background layer in the Layers dialog to make it

the active layer. Choose the Move tool from the Toolbox. Hold

down the Shift key and click and drag in the image window to

move the woman and vignette around under the mask. Moving the

source image around under the mask may not be enough to get a

good result – you may need to adjust the text layer font size,

tracking or line spacing. You may even need to try a different font.

If any of this becomes necessary, turn off the visibility of the mask

layer first and then duplicate the Text layer. Duplication is

necessary so you keep a copy of the last settings. Adjust the font

settings in the text layer duplicate. Then repeat the selection,

invert, copy and paste process to create a new mask. LXF

Quick

tip

Generate lots of

random text using

the free Lorum

Ipsum generator:

www.lipsum.com

This is the final image, except that you may want to adjust

the position of the mask over the background image.

Next month Gimp has tons of selection tools – we’ll look at the most useful.

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