TRACEELEMENTS
An IOS app for tracing bitmap images.
You can import images and choose settings to trace Black and White, Colour or Greyscale Vectors and export as an SVG file.
Start by opening a photo from your Photo Library that you would like to convert to a vector.
Choose photos where the resolution is large enough to make tracing easier. Around 1000 x 1000 is reasonable. The higher the resolution, the longer the tracing will take.
Choose whether the tracing is a single black tracing -BW-, a greyscale tracing -Greytones- or colour tracing -Colour-.
Adjust the image size. This affects both the resolution of the input image and the size of the final vector. Choosing a larger number will increase the tracing time.
When selecting colour tracing, you can use either K Means or Median to reduce the colours. Experiment with both for the best result. K Means will choose the best colours based on machine learning and the result will be different each time. Median Cut will choose the most common colours and will be consistent each time.
With K Means, colours may differ each time you preview the image. Turn off 'Resample' to fix the colours.
Median colour reduction provides consistent colours with each preview.
Use the 'Number Colours' slider to determine the levels for the tracing. A higher number will increase the tracing time.
For black and white tracing, adjust the 'Black Threshold' slider to modify the contrast of the final tracing.
For greyscale tracing, use the 'Gray levels' slider to adjust the number of grays in the final tracing.
'Simplify' reduces the number of nodes in the final vector. You can make more stylised tracings if simplification is high. Low simplification will give more accurate tracings but a higher node count, Higher 'Simplify' settings result in larger gaps unless you stack the layers.
Adjust 'Edge Detection' to interpret straight lines. Higher settings result in smoother curves, lower settings detect more straight lines. If tracing text you may need to set this level higher to straighten some text edges.
Modify 'Curve Flatness' to adjust the curve in line segments. Detected straight lines remain unaffected. A high setting will make the curved lines more pronounced. A low setting will make the curved lines completely flat/straight.
'Inverse' reverses the black and white tracing. Black will be white and white will be black.
'Stack' eliminates gaps between colour layers.
Stacked layers look better but are complex to separate in vector software because each layer depends on the layer below for its colour. Tiled layers are easier to work with and separate.
With 'Simplify' and 'Edge Detection' set to zero, you can trace around exact pixel shapes. Tiled layers will have no gaps, ideal for pixel art or sprites.
Both 'Preview' and 'Convert' trace the image. 'Convert' is slower and used for the final tracing.
Select 'Export' from the bottom menu to export the final SVG file. It's a standard layered SVG compatible with software like Affinity or Inkscape.