Manage Presentation Ink Objects in Python

Introduction

PowerPoint provides an ink feature that allows you to draw freeform strokes. Ink can be used to highlight other objects, show connections and processes, and draw attention to specific items on a slide.

The aspose.slides.ink namespace contains the classes needed to work with ink objects. For example, the Ink class represents an ink object on a slide.

Differences between Regular Objects and Ink Objects

Objects on a PowerPoint slide are typically represented by shape objects. In its simplest form, a shape is a container that defines the area of the object itself (its frame) along with properties such as the container size, shape, and background. For more information, see Shape Layout Format.

However, when PowerPoint handles an ink object, it ignores all properties of the object frame (container) except its size. The size of the container area is determined by the standard Ink.width and Ink.height properties:

ink_powerpoint1

Ink Traces

An ink trace is a basic element used to record the trajectory of a pen as a user writes digital ink. A trace stores a sequence of connected points.

The simplest form of encoding specifies the X and Y coordinates of each sample point. When all connected points are rendered, they produce an image like this:

ink_powerpoint2

Brush Properties for Drawing

A brush is used to draw lines that connect the points of an ink trace. Its InkBrush.color and InkBrush.size properties control its color and size.

Set Ink Brush Color

This Python code shows how to set the color of an ink brush:

import aspose.slides as slides
import aspose.pydrawing as draw

with slides.Presentation("pres.pptx") as presentation:
    ink = presentation.slides[0].shapes[0]
    brush = ink.traces[0].brush
    brush.color = draw.Color.red

Set Ink Brush Size

This Python code shows how to set the size of an ink brush:

import aspose.slides as slides
import aspose.pydrawing as draw

with slides.Presentation("pres.pptx") as presentation:
    ink = presentation.slides[0].shapes[0]
    brush = ink.traces[0].brush
    brush.size = draw.SizeF(5.0, 10.0)

Generally, a brush’s width and height do not match, so PowerPoint does not display the brush size (the corresponding data section is grayed out). When the brush width and height match, PowerPoint displays its size this way:

ink_powerpoint3

For clarity, let’s increase the height of the ink object and review the important dimensions:

ink_powerpoint4

The container (frame) does not account for the size of the brushes—it always assumes that the line thickness is zero (see the previous image).

Therefore, to determine the visible area of the entire ink object, the brush size of its traces must be taken into account. Here, the target object (the handwritten text trace) has been scaled to the size of the container (frame). When the size of the container changes, the brush size remains constant, and vice versa.

ink_powerpoint5

PowerPoint uses similar behavior for text objects:

ink_powerpoint6

Control Ink Appearance During Export and Rendering

Aspose.Slides provides the InkOptions class to control how ink objects appear in exported or rendered output. You can use its properties to hide ink completely or change how ink brush mask operations are interpreted.

Ink options are available through the export or rendering options for several output types:

Output Ink options property
PDF PdfOptions.ink_options
HTML HtmlOptions.ink_options
SVG SVGOptions.ink_options
TIFF TiffOptions.ink_options
Slide image RenderingOptions.ink_options

The same two settings are available through these properties:

  • InkOptions.hide_ink determines whether ink objects are included in the output. Its default value is False.
  • InkOptions.interpret_mask_op_as_opacity determines whether a mask operation is interpreted as opacity when rendering an ink brush. Its default value is True; set it to False to use the ROP operation instead.

Hide Ink Objects in PDF Output

By default, ink objects remain visible during export. Set InkOptions.hide_ink to True when you need a clean output without handwritten annotations or other ink content.

The following Python example exports a presentation to PDF while hiding all ink objects:

import aspose.slides as slides

with slides.Presentation("presentation.pptx") as presentation:
    pdf_options = slides.export.PdfOptions()
    pdf_options.ink_options.hide_ink = True

    presentation.save("presentation_without_ink.pdf", slides.export.SaveFormat.PDF, pdf_options)

Hide Ink Objects When Rendering a Slide as an Image

To hide ink objects when rendering slides as bitmap images, configure RenderingOptions.ink_options and pass the rendering options to the Slide.get_image method.

The following Python example renders the first slide as a PNG image without ink objects:

import aspose.slides as slides

with slides.Presentation("presentation.pptx") as presentation:
    rendering_options = slides.export.RenderingOptions()
    rendering_options.ink_options.hide_ink = True

    with presentation.slides[0].get_image(rendering_options) as image:
        image.save("slide_without_ink.png", slides.ImageFormat.PNG)

Control Ink Mask Rendering

The InkOptions.interpret_mask_op_as_opacity property controls how mask operations are interpreted when rendering ink brushes. The default value is True, which uses opacity. Set the property to False to use the ROP operation instead.

The following Python example exports a slide to SVG and uses ROP-based rendering for ink mask operations:

import aspose.slides as slides

with slides.Presentation("presentation.pptx") as presentation:
    svg_options = slides.export.SVGOptions()
    svg_options.ink_options.interpret_mask_op_as_opacity = False

    with open("slide.svg", "wb") as svg_stream:
        presentation.slides[0].write_as_svg(svg_stream, svg_options)

The same setting can be applied through TiffOptions.ink_options when exporting a presentation or rendering a slide to TIFF.

Choose Whether to Hide or Preserve Ink

Set InkOptions.hide_ink to True when the exported file should be a clean version of an annotated presentation, for example, a final copy intended for distribution without review marks.

Leave InkOptions.hide_ink at its default value of False when ink annotations are part of the intended content, such as review comments, handwritten notes, highlights, or drawings that should remain visible in the exported result. This allows applications to generate separate review and final outputs from the same presentation without modifying the source ink objects.

FAQ

Can I change the color or size of an existing ink stroke?

Yes. Get the trace from Ink.traces, then change its InkTrace.brush. You can set the brush’s InkBrush.color and InkBrush.size properties.

Does hiding ink change the source presentation?

No. InkOptions.hide_ink affects only the rendered or exported result; it does not remove or modify ink objects in the source presentation.

Which export formats support ink options?

You can configure ink options for PDF, HTML, SVG, TIFF, and bitmap slide images through the corresponding export or rendering options shown above.

Further reading

Manage PowerPoint Shapes in Python Manage PowerPoint SmartArt in Python