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Use Inkscape to draw snow capped text

2023-11-27T12:00:00.000+08:00

Making snow capped text is simple to draw using Inkscape's Select (S) and Node (N) tools. This post shows the steps to draw the snow capped text on the text Merry. The final drawing is shown in the screenshot below.

First thing is to draw the text Merry with the Text(T) tool on the canvas.
Next, using the Bezier (B) tool, draw a straight line to the side.
Adjust the style of the line. Remove the fill and change the stroke paint color to white. Change the stroke join to rounded, cap to rounded. Thicken the stroke width to e.g. 4 pixels.
Select the line and make a duplicate by pressing CTRL-D.
Using the Select (S) tool, move the duplicate line to the top of the letter M.
Then, click the Node (N) tool.

The nodes appear on the line.
Press CTRL and drag the right node handle to the left.
Repeat the previous steps to duplicate, move the line to the other part of the M letter.
Duplicate the line and move it to the top of the letter e.
Click the Node (N) tool. Then click the Insert new nodes into selected segment icon (first one on the tool bar).

A new node is inserted into the line.
Using the Node tool, drag the side nodes down.
Select the center node. Then click the Make selected nodes symmetric icon (highlighted in red circle on the right below) in the Nodes tool bar.

The segment becomes rounded.

Note: Adjust the nodes using the Node tool to your liking.
Repeat the previous steps to cap the remaining text.

Make a snowflake using the Inkscape pen tool

2023-11-12T19:46:00.004+08:00

This post shows some steps in using Inkscape to draw a simple snowflake using the Pen, snapping, duplicating and rotation tools.

Open Inkscape and create a new document.
Click the Snapping icon to ensure that the Toggle Snapping is on.
In the toolbar, click the Pen Tool icon or press B on the keyboard.
On the drawing page, press down CTRL and draw a horizontal line to represent the main snowflake trunk.
If necessary, change the stroke style with the Fill and Stroke pane, e.g. thick blue 10px solid line.
Draw the "branches" of the snowflake. Press down CTRL and click a starting point away from the main branch. Then move the cursor towards the main branch.

Note: Click the second point when the cursor is snapped to the trunk center line.
Use the Selector tool to select all the branches (not the trunk).
Press CTRL-D to duplicate the selected branches. Then press V to Flip Vertical the duplicated branches. Finally use the Selector tool to select all the branches and trunk.
Press CTRL-g to group all the selected branches and trunk.
Click the selected group again to show the rotation handles.
Press down CTRL and move the rotation pivot point to the base of the trunk, as shown in red above.
Press CTRL-D to duplicate the group. Then press down CTRL and drag rotate the group handle to 45 degrees clockwise.
Repeat the previous step until the snowflake is complete.

Quicky check image values in Krita

2023-03-24T11:29:00.014+08:00

I usually use a black layer in color blend mode as the top layer to check the values of an image. That takes quite a few clicks to get working. But recently I learnt of a faster way to do it with Soft proofing and that just takes only one or two clicks, depending on how you count.

First, you need to setup the soft proofing to gray scale as follows:

Setup Soft Proofing

In Krita, select the menu options Settings | Configure Krita.

The Configure Krita dialog box appears.
Select Color Management. Then click the Soft Proofing tab.
In the Model field, choose Grayscale/Alpha.
In the Proofing Rendering Intent field, choose Perceptual.
Click OK.

Use Soft Proofing on an image

Once set up is done, open up any image and do the following to see the image in grayscale to check the values.

In Krita's menu, select View | Soft proofing. Or press CTRL-Y on the keyboard.

The color image changes to grayscale.
Toggle off the soft proofing by repeating step 1.

The image changes back to a color display.

Apply a canvas texture to a digital painting with Krita

2023-02-24T21:27:00.003+08:00

I wanted to make a digital painting appear to have a canvas texture, to make it look like any traditional paintings. In Krita, it is easy to apply a canvas texture over the digital paint layers. In a nutshell, you just need to create an overlay paint layer with a tiled canvas texture image applied with some transparency applied. Or in more details, do the following:

Create a canvas texture paint layer

In Krita, open up a digital painting file that you want to create a canvas texture for.
In the Layers docker pane, click the + icon, as shown in the screenshot above.

A new paint layer Paint Layer x is created. Where x is a running number.
Move the newly created paint layer above all the painted layers either dragging it above or you can use the arrow up/down icons. Name the layer as Canvas texture.

Select a canvas texture file

Click the Fill patterns icon in the tool bar.

A drop down showing a grid of patterns appear.
Click on a pattern to use, e.g. 02_rough-canvas.png.

Apply the canvas

Make sure the Canvas texture layer is active. Then in the menu, select Edit | Fill with Pattern.

The pattern is applied across the canvas texture layer.
Next, in the Layers docker pane, change the blend mode to Overlay.
Then, adjust the opacity to your satisfaction, e.g. 20%.

The digital painting should look more like a traditional painting.

3DPhoto of Manukan Island at sunset

2019-05-24T20:15:00.000+08:00

According to Wikipedia https://en.wikipedia.org/wiki/Manukan_Island, Manukan Island is the second largest island in the Tunku Abdul Rahman National Park, Sabah. This is a Facebook 3DPhoto taken just after the sun has set and what a glorious colorful sunset it was. Click the image below to view.

3DPhoto of the Cloud Gate (Chicago Bean) sculpture in Chicago

2019-05-10T21:56:00.000+08:00

The Cloud Gate sculpture (nicknamed as the Chicago Bean) is located at Chicago's Millenium Park. It was a cold winter day when I took this photo with a Canon DSLR. Now I made it into a Facebook 3D photo by painting a grayscale disparity/depth map using Gimp's brushes, selection tools, gradient fill and transparency masks.

3DPhoto of Sunset at MacRitchie Reservoir, Singapore

2019-05-08T22:32:00.001+08:00

This photo was taken at Singapore's MacRitchie Reservoir at sunset using a Canon Powershot digital camera. The disparity/depth image (see the animated thumbnail) that gives the 3D parallax effect as seen in the embedded Facebook image was generated using Gimp's gradient, brushes, selection and channel tools.

3DPhoto of Claude Monet's Wheatstacks (End of Summer) 1890-1891 painting

2019-05-04T14:36:00.000+08:00

This grayscale disparity image/depth map for generating a Facebook 3DPhoto image of Claude Monet's Wheatstacks (End of Summer) 1890-1891 oil on canvas painting was created using the Krita Painting application. The resultant 3DPhoto can be seen in the embedded iFrame below.

More information about Monet's haystacks can be found on Wikipedia https://en.wikipedia.org/wiki/Haystacks_(Monet_series).

3DPhoto of Vincent Van Gogh's Bedroom in Arles (1889)

2019-05-03T21:52:00.000+08:00

This is Vincent van Gogh's second version of The Bedroom in Arles (1889) rendered with in Facebook's 3DPhoto viewer. To enable the 3D parallax effect, Gimp was used to paint the disparity image or depth map in grayscale as can be seen in the black and white thumbnail on the left.

For more information about the van Gogh's painting can be found in Wikipedia https://en.wikipedia.org/wiki/Bedroom_in_Arles

3DPhoto of Georges Seurat's A Sunday on La Grande Jatte painting

2019-05-01T19:30:00.000+08:00

From Wikipedia (https://en.wikipedia.org/wiki/A_Sunday_Afternoon_on_the_Island_of_La_Grande_Jatte): A Sunday Afternoon on the Island of La Grande Jatte (French: Un dimanche après-midi à l'Île de la Grande Jatte) painted in 1884, is Georges Seurat's most famous work. It is a leading example of pointillist technique, executed on a large canvas. Seurat's composition includes a number of Parisians at a park on the banks of the River Seine.

I thought it would be cool to paint a disparity/depth map with Gimp to convert Georges' painting to a so-called Facebook 3DPhoto; and the result is shown embedded below.

Image background removal using Krita

2019-04-12T12:00:00.000+08:00

Like other image editing software such as Gimp or Photoshop, Krita has similar tools to remove the background of an image non-destructively using transparency masks.

The following steps show how:

Open up an image in Krita.
In the Layers pane on the right, mouse right click on the paint layer.

A pop up menu appears.
Choose Add | Transparency Mask.

A transparency mask sub layer is created underneath the paint layer.
Draw a selection polygon roughly around the foreground object in the image using the Polygonal Selection Tool, as shown below. Then in the File menu, click Select | Invert Selection.
Choose Black as the foreground color. Choose a Brush e.g. Basic-1 Ink. Make sure the transparency mask layer is selected or active. Then paint over the background.
Choose Select | Deselect to remove the selection polygon.

The marching ants selection polygon is removed.
Make the brush size smaller and zoom closer to the background - foreground boundary. Brush over the remaining background.

That's it. The background is removed in a non-destructive manner from the image.
Note: if you made a mistake in removing some foreground pixels, simply change the foreground color to white and paint over the problem area to bring back the foreground pixels.

SVG abstract colorful geometric background for download

2019-04-09T20:11:00.000+08:00

I made this free colorful abstract geometrical background and published it on the OpenClipart site. Click here https://openclipart.org/detail/318138/abstract-colorful-geometric-background to download.

Using Krita's Colorize Mask Editing Tool to color line art drawings

2019-04-04T20:18:00.002+08:00

The usual way to color line art drawings in digital image manipulation software is to use a Color Fill tool to fill an area bounded by line work.

Krita has a useful tool called the Colorize Mask Editing Tool which allows you to simply draw a patch inside the line work with the color you want to fill. Once all the color patches have been drawn, you could preview the color fill and if everything is to your satisfaction, you can just click a button to save the color fill permanently.

The following steps illustrate:

Start Krita. Open up a line work drawing e.g. christmas_tree.svg.
Then in the main tool bar, click the Colorize Mask Editing Tool, as highlighted in a red circle in the screenshot above. Then click on the drawing.

The line work becomes transparent. A new Colorize Mask layer is created.
If a brush is not selected, then choose a brush e.g. Basic-1. Adjust the brush size if necessary. Then use the Advanced Color Selector pane to choose the desired color for the fill.
Inside the line art drawing, draw color patches as shown below.
Then activate the Tools Option pane and click the Update button to see the changes.

A preview of the color fill is displayed.
Toggle the option Edit key strokes off to display a preview without the color patches.
If the color fill is acceptable, then you can make it permanent by converting the Colorize Mask layer into a Paint Layer. If not, redo the previous steps.

Cretan Ram sketch

2014-04-14T12:39:00.002+08:00

I just did a sketch of a Cretan Ram done using the Serious Paint Android app on a Nexus 7 tablet. Brushes used were the Pencil and Smear brushes.

And colored with a Soft Shader brush

Digital Dog Portrait

2013-06-11T20:57:00.000+08:00

Another digital art piece done using the Android App - Serious Paint on a tablet. This time I was trying out different brushes - pencil, soft shader, and blend, and varying the brush diameter. I used the Save function to save the work-in-progress at different stages this time, as shown below. I must say the Blend brush result looks like blending charcoal with my finger.

Pencil sketch outline

Beginning color shading

Final piece

I used a rubber tip stylus and at times my finger. Sometimes, I wish the stylus was more sensitive and it didn't drag and stick on the screen as much.

Portrait of a cat painted on a tablet using the Serious Paint Android app

2013-05-29T16:41:00.002+08:00

Here is a digital art of a cat(!) painted on an HP Touchpad running Android Jelly Bean using this nice free app - Serious Paint and a cheap rubber tip stylus. The Serious Paint app looks similar to another Android app for painting - Infinite Painter but it is much more stable; Infinite Painter keeps crashing all the time to the point that you can't do anything worthwhile.

How to clip lines with a polygon using Inkscape

2013-05-28T16:29:00.000+08:00

In Inkscape, the Clip function can be used to clip one or more lines with a polygon. The trick is to group all the lines together before clipping as shown in the example below.

In Inkscape, select all the vector lines using the Select and transform objects tool (F1).
Select Object | Group.

The lines are grouped as one.
Now select the polygon.
Select Edit | Copy to make a copy of the polygon. Then select Edit | Paste in Place.

The polygon is copied and pasted on top of the lines.
Now press SHIFT and click to select the group of lines together with the polygon.

The polygon and the group of lines are selected.
Select Object | Clip | Set.

The lines are nicely clipped to the polygon.

Use Raw Therapee to reduce noise in photo images

2013-04-09T20:54:00.001+08:00

Photos taken in low light and high iso situations may look noisy at 1:1 resolution. An example of a moderately noisy image is shown below.

Raw Therapee has a good noise reduction function which can be accessed by clicking the Detail pane on the right. This will display the Sharpening, Noise reduction and Defringe settings as shown in the screenshot below.

Toggle on Enabled for Noise reduction. Then gradually adjust the Luminance, Chrominance or Gamma values and observe the level of noise in the image preview until the noise is reduced to your satisfaction.

Then press CTRL+S and save the image into an output TIFF, JPEG, or PNG file.

Getting Raw Therapee to work with raw Hasselblad files (.3fr and .fff)

2013-03-15T11:01:00.000+08:00

Raw Therapee can display and work with the raw Hasselblad camera files - those with the file extensions (*.3fr and *.fff). However, they will not be visible until you change Raw Therapee's preferences to add in the Hasselblad file extensions as shown below.

Start Raw Therapee.
Click the Preferences button.

The Preferences dialog box appears.
Click the File Browser tab.
In the Add Extension field, type in 3fr. Click +.

The extension 3fr is appended to the list.
In the Add Extension field, type in fff. Click +.

The extension fff is appended to the list.
Click OK.

Raw Therapee will now be able to display raw Hasselblad files.

Correct image perspective using Raw Therapee

2013-03-14T21:12:00.001+08:00

Raw Therapee has some useful tools for correcting horizontal and vertical perspectives in photo images. The perspective problem is more noticeable on photos taken using wide angle lens e.g. 24 mm or wider, as shown in the screenshots of tall buildings below. In this example, the Transform tools will be used to correct a JPEG image's vertical perspective problem.

Start Raw Therapee. Use the File Browser command to locate and display the image for editing.
On the right, click the Transform tab.
Click Perspective. Drag the Vertical slider left or right and observe the image. Stop when the buildings are aligned vertically.

The perspective is corrected.
Press CTRL+S.

The Save dialog box appears.
Type in a file name and choose a folder and/or format. Click OK.

The file is saved.

Correct an overexposed JPEG photo image with RawTherapee

2013-03-13T11:14:00.000+08:00

Although the free and open source software Raw Therapee is designed for processing raw camera images, it is possible to use its exposure correction tools to fix problems with JPEG images. As an example, this post demonstrates how to use Raw Therapee to correct a JPEG image for overexposure.

Start Raw Therapee.

The Raw Therapee application window appears.
Use the File Browser, Places and Recent Folders panes on the left to browse and select a folder containing the photo(s) to be edited. Double click on the image to open it for editing.

The image is displayed in the application window.
Observe the histogram on the right.

The red, green, blue, and white curves are bunched to the right with a large spike at the end.

Note: this is an indication of over exposure clipping.
Under the Exposure pane, drag the Brightness slider to the left to reduce the brightness. At the same time, observe the histogram to ensure that the curves do not get clipped to the left.

The image brightness is reduced.
Drag the Contrast slider to the right to increase the contrast. Observe the histogram to ensure that as the curves spread, both sides do not get clipped at the sides.

The Exposure settings may look like these.

More contrast is applied to the image.
To save the file, press CTRL+S.

The Save dialog box appears.
Specify the output file parameters. Click OK.

The file is saved.

Fast method to create a button icon with a 3-D effect using Inkscape

2012-12-06T23:07:00.000+08:00

Inkscape can be used to create nice looking button icons with a touch of 3-D like the example on the left. It can be achieved simply by applying a linear fill gradient to the button and a linear gradient to the path's stroke segment on top, with appropriate gradient colors and opacity values; and a little blurring.

The following illustrates how it can be done.

In Inkscape, create a blank document set to a desired output dimension, e.g. 128 by 128 pixels.
Click the Create rectangles and squares (F4) icon. Place a rounded rectangle on the canvas. Change the rectangle width an height to the desired values e.g. 96 by 96 pixels.
Press CTRL+C. Then press CTRL+ALT+V.

A copy of the rounded rectangle is placed on top of the original rectangle.
Reduce the dimensions of the copy to e.g. 88 by 88 pixels.
In the Align and Distribute pane, set the alignment to be Relative to Page. Then click the Center on horizontal axis and Center on vertical axis icons.

The copy is centered on the page.
Select Path | Object to Path.

The copied rectangle is converted to a path.
Press F2. Then drag a rectangle to cover the bottom nodes as shown.

The bottom nodes are selected.
Click on the Delete segment between two non-endpoint nodes icon.

The selected segments are deleted.
Press F2. Drag a rectangle to cover the bottom two nodes. Press the ARROW UP key to nudge them upwards until they are at the half of the rectangle.
Press F1. Click on the original rectangle. Then remove the stroke.
In the Fill and Stroke pane, under the Fill pane, click the Linear gradient icon.
Then click the Edit button.

The Gradient editor dialog box appears.
For the first stop, set it to a color of your choice with full opacity (alpha value of 255).
For the second stop, set it to a darker shade of the color of your choice with full opacity. Close the Gradient editor.
On the canvas, drag the node of the lighter color gradient to the top and the darker shade node to the bottom.
Press F2. Click the stroke path.
In the Fill and Stroke pane, change the Stroke style width to a larger value e.g. 2 pixels.
Under the Stroke Paint tab, change to a linear gradient. Click the Edit button.

The Gradient editor appears.
For the first stop, set the stop RGB color to white with an alpha value of 178.
For the second stop, set the stop RGB color to black with an alpha value of 0. Close the Gradient editor.
Press F2. Drag the lighter gradient node to the top. Drag the more transparent gradient node to the bottom.
In the Fill and Stroke pane, change the stroke blur to a slightly larger value e.g. 2.

The button base with a slight 3-D effect is now done.
Place any artwork above the button to complete the icon.

Restoring yellowed paper scan using self-screen blend mode in Gimp

2012-11-29T21:59:00.001+08:00

In Gimp or Photoshop, you can overlay an image with itself and blend the layers together with a blending mode e.g. multiply, dodge, burn, screen, etc. I found that a self-image blend i.e. an image with itself, with the screen mode can restore yellowed paper quite nicely and easily. By definition, the screen blend mode will lighten colors but leave black neutral and untouched. Using this technique, I managed to restore the yellowed paper scan below to a reasonably looking version quickly.

Run Gimp. Open up the yellowed paper image.
In the layers pane, right click on the yellowed paper image.

A pop up menu appears.
Choose Duplicate Layer.

The layer is duplicated.
Choose the duplicated layer. Then click the Mode combo box as shown below.
In the drop down list, choose Screen.

The screen blend mode is applied. The yellowed paper is restored and looks less aged.

Digital Traditional Color Palette

2012-11-02T13:04:00.000+08:00

I was having difficulty in locating a digital traditional color palette for digital painting so I made this digital traditional color palette from the default swatch of Photoshop.

Crop an image with the Fill Pattern command in Inkscape

2012-10-26T21:54:00.000+08:00

In Inkscape there is no direct image crop command similar to Photoshop's Image Crop command. But it is still possible to crop an image in Inkscape indirectly using the Fill Pattern command. An example of a cropped image is the screenshot on the right. The example below shows how it is done.

Start Inkscape. Drag and drop an image file onto the page.

The "image" Input dialog box appears.
Click OK.

The image is displayed.
Use any vector placement commands to draw the cropping boundary e.g. the Create circles, ellipses, arcs (F5) command.
Press F1 and select the image.
Select Object | Pattern | Objects to Pattern.

The image pattern is created.
Delete the image. Select the cropping boundary.
If the Fill and Stroke pane is not displayed, select Object | Fill and Stroke.

The Fill and Stroke pane is displayed.
In the Fill tab, click the Pattern icon. If necessary, choose a pattern from the Pattern Fill combo box.

The image is displayed cropped within the boundary.