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How To Trace A Bitmap In Inkscape


In an earlier Inkscape tutorial we showed how to use the trace bitmap feature to create a butterfly graphic, so in this tutorial we'll look at the basics of tracing a bitmap in a little more detail. We'll cover how to trace a monochrome image then look at a few possibilities of working with a colour image.

How To Trace A Monochrome Bitmap in Inkscape

Tracing a monochrome image is quite straightforward and takes just a few steps:


1/ Import an image into Inkscape and make sure its selected.


2/ Now select Path > Trace Bitmap.

3/ The above window will open. For monochrome images Brightness cutoff seems to work well. For this option the Threshold can be edited, (highlighted in red). We'll try three threshold settings to see how they compare, starting with a setting of 0.350.

If you'd like to see a preview of the traced bitmap click the Live Preview option (highlighted in blue).

When you're ready click OK.


4/ The new traced bitmap will be added in the Inkscape window and will be placed on top of the original. The new image can be dragged away from the original image.

That is all there is to tracing a bitmap image in Inkscape, however as mentioned above, we can change the threshold setting to see how this affects the traced bitmap.


5/ After setting the threshold to 0.350 then hitting OK, change the threshold to 0.450, make sure the original image is selected and again hit OK.

After setting the threshold to 0.550 again select the original image and hit OK once more. You'll now have three traced bitmaps similar to the above, showing how changing the threshold  alters the tone of each image.

Tracing A colour Bitmap In Inkscape

Tracing a colour bitmap in Inkscape is not too different than tracing a monochrome image, although we can use other settings.


1/ As before import an image into Inkscape then select Path > Trace Bitmap.

2/ Rather than using the Brightness cutoff option we'll select Colors (highlighted in red). With this option we can also select how many times Inkscape will scan the image (highlighted in blue). Here it is set to 8.

When you're ready hit OK.


3/ The traced bitmap will again appear directly over the original image, and can be dragged to the side.


4/ Since we selected 8 scans earlier the new image will be made up of 8 layers. This can be seen by first selecting Object > Ungroup.


5/ Now click away from the image then drag each layer to its own space. as in the image above. You'll see the 8 layers.

6/ A color bitmap can also used to create a monochrome image. To do this we'll select Grays (highlighted in red).

With this option we can again select how many times Inkscape scans the image. We'll leave it at 8.

Click OK when you're ready.


7/ The above image shows the original image with the traced bitmap.


8/ Since the bitmap was traced 8 times it is again constructed of 8 layers. They can be ungrouped as in the color bitmap example.


That is essentially the basics of how to trace a bitmap in Inkscape. There are more settings and options to play with, so feel free to play with them and see what they can do. You won't break anything by doing this.

We hope this has been helpful and if so come back soon for more, and why not check out our YouTube channel where you can also watch a video version of this tutorial.