Category: Slidium

Using images in a Slidum Markdown presentation

svg icon in markdown presentation

Images are an important part of a presentation and Slidium supports different ways to use them in your slides.

Even if images are managed using the regular Markdown syntax, reading this guide is important to fully understand the specificities of the application.

Markdown syntax for images

Regular syntax

![alt text]( "Title")

You can specify a title but for the moment, there is no real usage of it.

Reference-style syntax

![alt text][logo]
[logo]: "Title"

Sandboxing and Slidium resources manager

Slidium is a sandboxed application and hence, by default, can only access to restricted locations.

Unfortunately, creating presentations often require to add content (images,…) located outside these trusted locations.

Slidium provides a resources manager that analyses the resources contained in your slides and asks you to allow it to read the folders where your images ares stored.

When you gives the read rights to Slidium, there are persistent and will be restored during the next launch of of the application

slidium images manager

Slidium images manager

Relative or absolute path?

Slidium can support relative image paths. It is only possible if the current presentation file is saved. Otherwise, Slidium is unable to calculate the relative paths.

When using relative paths, you need to keep in mind that if you move the file, you need to move images as well. It is recommended to keep both presentation file and images in the same folder.


When you specify an image, you need to specify an URL. It means a valid URL. For instance, you cannot have spaces, they have to be escaped and replaced by %20.

Adding images

Slidium offers different ways to add images to your slides:

By typing them

It is the most basic one. However, this is not the easiest way. You need to remember the exact path to the image.

By using drag and drop

This is the preferred method. Drag any image from the Finder and drop it in Slidium, at the place you want to insert it. Slidium will add the markdown tag around it.

By using the insert menu option

It will open a regular file open dialog allowing you to select the picture you want to insert.

Images as full slide background

In addition of using images as part of the slide, Slidium allows to define a full slide background image as slide metadata.

It has several benefits:

  • You can have a different transition for the background and the content.
  • Caching is more efficient, especially if you are using large images and if the running hardware is limited (having an iOS version of Slidium is not science fiction).

You just need to inform the URL of the image after Background meta data key, like this example:


Background: path/to/image.jpg

SVG icons

Sometimes you need more that bitmap pictures, you need an easy way to add a simple icon to illustrate.

Slidium comes bundled with hundred of SVG icons, powered by !!!!linea!!!! icons sets.

They are multipurpose and render nice at all resolutions.

The syntax is similar to a regular image, instead of indicating the path to the image, you just need to inform the SVG icon name.


Remembering all the names is not an easy task and ad no value. Slidium hence provide a completion list. You can start to type the first letter of an icon, and you will get a list of available graphics with their preview.

svg icon in markdown presentation

Slidium 0.8 is available

markdown presentation welcome screen

The second public beta of Slidium has just been released. In addition of bug fixes and performance enhancements, it brings also new features.

A brand new welcome screen

It was difficult for someone discovering Slidium to start to use it. I tried to improve that aspect:

  • Create a new presentation directly by choosing your theme
  • See provided example
  • Easily remember your recent presentations

New themes

In addition of the modern theme, available since the beginning, 3 new themes are part of version 0.8:

  • Gertrude, a port of the same theme from slidecarnival
  • Fidele, another port again from Slidecarnival
  • Reveal, from reveal.js. For the moment it only support the black theme of reveal.js

These themes are a work in progress and do not yet contain all the layouts and features.

Other new features

  • Support for relative image paths. If your presentation is saved (otherwise Slidium is unable to calculate relative paths to something which is not on the filesystem), Slidium now support relative paths to images and other resources.
  • More transitions (convex, concave)
  • Default layout in themes

Bug fixed and performance enhancements

  • Graph generation
  • Slides rendering

You can download it here

Using markdown graph in a presentation

using graph in a markdown presentation

Having the ability to simply add graphs in a markdown presentation if one of the reasons why Slidium has been created.

Markdown presentations framework are powerful but you often need to use a third party software to generate graphs and then to copy and paste them as an image in your slides. I do not like this type of work-flow. Each time you need to change a value or a colour of your graph, you need to go again in the other application, regenerate the graph, export it to bitmap, …

Graphs are a powerful feature of Slidium. They are generated in SVG and can be scaled up and down while staying pixel perfect.


  • We call a series a consistent set of data
  • We call data-point a value of a series.
  • Each series has a name and a set of value.
  • They are both separated by a colon :
  • Each value is separated by a coma ,

    Example : Budget: 120, 130, 140

Types of graphs

Slidium supports 6 different types of graphs, adapted to the majority of situations.

  • Line {{line-chart}}
  • Spline {{spline-chart}}
  • Area {{area-chart}}
  • Bar {{bar-chart}}
  • Donut {{donut-chart}}
  • Pie {{pie-chart}}

Line, spline, area and bar charts can be used with multiple values per series. Donut and pie only use a value par series.


For the Y axis, scale and values are defined automatically based on the minimal and maximal values of your data.

For the X axis, you can also let Slidium to calculate them automatically. However in the majority of cases, you will need to provide your own values.

Note: Providing custom X axis value only make sense for graph types supporting multiple values per series.

You can set your own values for a graph by declaring an additional series having x as name: Example:

- Budget: 120, 130, 150
- x: 2015, 2016, 2017
example of spline graph

example of spline graph

Other information about graphs

  • Graphs are generated with a C3js based chart renderer.
  • Each part of the generated SVG graph has CSS classes allowing to customisation from the presentation theme.

Slidium 0.7 (beta) is now available

I am proud to announce the availability of the first public beta of Slidium, my next generation Markdown Presentation app for Mac.


  • It’s a beta, and even the first one, so be sure you will find issues. Thanks for helping me by reporting them.
  • It only contains a single theme. I have several other ones in progress but none of them were finished enough.
  • Only English. Other localisations will come with future beta.
  • Only mac OS X 10.12 is supported but support for 10.11 is planned too.
  • Documentation is minimalistic but a series of blog post are coming soon to present the main aspects of Slidium. However, I hope that application is simple enough to be used without frequent use of documentation.
In conclusion, a lot of “coming soon” but it should give a good overview of Slidium. Your feedback is really important. Do not hesitate to report issues or features requests. This beta will expires the 3rd of April.
Download 0.7 beta

Introducing Slidium : The new way to write Markdown Presentations for Mac

markdown presentation

How to write markdown presentations easily?

Today I am proud to introduce Slidium, a Markdown presentations editor for the Mac, which has been started 2 years ago and soon in beta.
During last ten years, in my “corporate life” I had to write presentations. Because it was a big company, I was really creating slides everyday. While I enjoyed to present, I disliked to create these presentations. I was not able to get a efficient writing work-flow.
In the meantime, I discovered Markdown and it quickly replaced my traditional word processor application. Unfortunately, I was unable to found a tool providing me the same comfort for presentations.
I started to develop my own with the following features in mind: Read More