Changes

Whether we capture using camera or an application called TuxPaint or Screenshot, the images have been captured digitally based on the resolution of the computer or mobile screen; this is indicated in terms of pixels.  Such images are called raster images and they are dependent on the resolution of the device for their quality.  All raster graphics or images are those that involve capturing some underlying image or object using various devices.  For more information on raster images, see [https://en.wikipedia.org/wiki/Raster_graphics here]. GNU Image Manipulation Program (GIMP) is an image editing software, that can edit and make raster images.  There is another kind of digital image called the [https://en.wikipedia.org/wiki/Vector_graphics vector graphics] which is not discussed in the toolkit.  Vector graphics or images involve creating drawings based on defined geometrical information; this can be defined in terms of the shapes and is not governed by the resolution of the device.  Inkscape is a tool that can be used to create and edit vector images.   

Whether we capture using camera or an application called TuxPaint or Screenshot, the images have been captured digitally based on the resolution of the computer or mobile screen; this is indicated in terms of pixels.  Such images are called raster images and they are dependent on the resolution of the device for their quality.  All raster graphics or images are those that involve capturing some underlying image or object using various devices.  For more information on raster images, see [https://en.wikipedia.org/wiki/Raster_graphics here]. GNU Image Manipulation Program (GIMP) is an image editing software, that can edit and make raster images.  There is another kind of digital image called the [https://en.wikipedia.org/wiki/Vector_graphics vector graphics] which is not discussed in the toolkit.  Vector graphics or images involve creating drawings based on defined geometrical information; this can be defined in terms of the shapes and is not governed by the resolution of the device.  Inkscape is a tool that can be used to create and edit vector images.   

GIMP can be opened from Applications--->Graphics--->GIMP Image Editor. GIMP stands for GNU Image Manipulation program.

GIMP can be opened from Applications--->Graphics--->GIMP Image Editor (image 7). GIMP stands for GNU Image Manipulation program.

GIMP is very powerful with many sophisticated features. We will learn a few commonly used functions in image editing:

GIMP is very powerful with many sophisticated features. We will learn a few commonly used functions in image editing:

# Cropping an image

# Cropping an image

# Adding text to an image

# Adding text to an image

# Reducing the size of an image

# Reducing the size of an image

Once you have opened the GIMP application, open the image you would like to edit. You can see the menu bar providing different options for editing the image.

Once you have opened the GIMP application, open the image you would like to edit (image 8). You can see the menu bar providing different options for editing the image.

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|[[File:COL-Opening_GIMP.png|thumb|450x450px|Opening GIMP]]

|[[File:COL-Opening_GIMP.png|thumb|450x450px|Image 7 - Opening GIMP]]

|[[File:COL_-_Opening_an_image_file_using_GIMP.png|thumb|450x450px|File opened in GIMP]]  

|[[File:COL_-_Opening_an_image_file_using_GIMP.png|thumb|450x450px|Image 8 - File opened in GIMP]]  

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==== Cropping an image ====

==== Cropping an image ====

Often, you want some part of a larger image to re-use in a different resource.  GIMP allows you to select parts of an image - in different shapes or even using a freehand selection to select parts of an image.   

Often, you want some part of a larger image to re-use in a different resource.  GIMP allows you to select parts of an image - in different shapes or even using a freehand selection to select parts of an image.   

[[File:COL_-_Crop_to_selection_of_an_image,_using_GIMP.png|thumb|450x450px|cropping an image using GIMP|left]]

[[File:COL_-_Crop_to_selection_of_an_image,_using_GIMP.png|thumb|450x450px|Image 9 - cropping an image using GIMP|left]]

This is different from a screenshot where you can only grab an area that is in the shape of a rectangle. You can select parts of an image from Select <u>Tools → Selection Tools → Free Select</u>  

This is different from a screenshot where you can only grab an area that is in the shape of a rectangle. You can select parts of an image from Select <u>Tools → Selection Tools → Free Select</u>  

You can move your cursor on the image to outline the area you want to crop, this is free hand, not necessarily in the form of a rectangle. Then crop the image to your selection through Image → Crop to Selection. We have cropped the image to free select only the teacher and the student (see the dotted line).

You can move your cursor on the image to outline the area you want to crop, this is free hand, not necessarily in the form of a rectangle. Then crop the image to your selection through Image → Crop to Selection (image 9). We have cropped the image to free select only the teacher and the student (see the dotted line).

You can export this cropped image using File → Export as and export to an image format like .png or .jpeg.

You can export this cropped image using File → Export as and export to an image format like .png or .jpeg.

You may want to add a caption to an image and make that caption a part of the image itself. You can do this using GIMP

You may want to add a caption to an image and make that caption a part of the image itself. You can do this using GIMP

[[File:Entering_text_on_an_image_using_GIMP.png|thumb|450x450px|Entering text on an image using GIMP|left]]

[[File:Entering_text_on_an_image_using_GIMP.png|thumb|450x450px|Image 10 - Entering text on an image using GIMP|left]]

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Select <u>Tools → Text.</u>  A text tool box appears.

Select <u>Tools → Text.</u>  A text tool box appears.

Place your cursor where you want to type your text. You can format the text (change font size, colour) through the Text tool box.

Place your cursor where you want to type your text. You can format the text (change font size, colour) through the Text tool box.

In our image, we have added the text ‘Digital Storytelling, Health centre’ and selected the yellow colour for the text, since it will display better against a dark background. (Tip - the text should be in a colour contrasting with the background, for easier visibility).  

In our image, we have added the text ‘Digital Storytelling, Health centre’ and selected the yellow colour for the text, since it will display better against a dark background (image 10). (Tip - the text should be in a colour contrasting with the background, for easier visibility).  

You too should enter captions on a few image resources which you have created for your OER, in this section.

You too should enter captions on a few image resources which you have created for your OER, in this section.

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==== Reducing the size of an image ====

==== Reducing the size of an image ====

Sometimes image files can be heavy (compared to text only files). You can reduce the size of an image using GIMP.  Select <u>Image → Scale image</u>.

Sometimes image files can be heavy (compared to text only files). You can reduce the size of an image using GIMP.  Select <u>Image → Scale image</u> (image 11).

[[File:COL_-_Scaling_an_image_using_GIMP.png|thumb|450x450px|Cropping an image using GIMP|left]]

[[File:COL_-_Scaling_an_image_using_GIMP.png|thumb|450x450px|Image 11 - Cropping an image using GIMP|left]]

You can reduce the resolution in the form that opens. The more you reduce the resolution, the greater the reduction of file size.

You can reduce the resolution in the form that opens. The more you reduce the resolution, the greater the reduction of file size.