Virtual mirror shows new lines

Shoppers can try on clothes without undoing a button using a virtual mirror developed by German researchers.

It was launched by scientists from the Fraunhofer Institute for Telecommunications, Heinrich-Hertz-Institut at the IFA consumer electronics show now taking place in Berlin.

The Fraunhofer team showed how customers could visualise themselves in a variety of shirts, ranging in colour and design.

The customer enters the virtual dressing room and stands in front of a television display with a camera mounted above it, which films them, registering how their clothing flows and moves.

Shoppers can use the new technology to ‘virtually’ try on a new item, such as a shirt, by choosing one on a touch screen.

An embedded software program takes into account the folds and creases in the clothes the customer is wearing to reproduce a virtual representation of the new shirt, even when they are moving around.

The shadows and lighting effects seen in the mirror are identical to those on the customer.

‘We’re mixing the real world with the virtual world,’ said Jürgen Rurainsky, one of the mirror’s early developers.

While he was not involved in this particular project, he was one of the lead researchers behind the virtual shoe-fitting mirror, which Fraunhofer developed last year for the Adidas flagship store in Paris.

The principle of the shoe-fitting mirror and that of the clothes mirror is similar, he said, except the new technology is able to take into account the folds that distort clothing when the wearer moves.

Textiles have elastic qualities, their structure is not always uniform and there are innumerable details that give each material its special appeal. These characteristics represent a challenge for the virtual mirror.

In order to reproduce elastic deformations such as those in a woven or knitted fabric, the Fraunhofer system evaluates multiple parameters and processes them simultaneously.

The camera shoots frames at intervals of a few milliseconds and transmits them to a memory unit. This analyses the images to determine what changes have taken place between successive frames.

The researchers accomplished this by superimposing a meshwork of triangles on each frame — a technique commonly used in computer graphics.

Since the content of the triangular fields does not necessarily change from one frame to the next, the system only compares those fields where changes have taken place.

This information is used to create a new virtual image of the item of clothing. The images are processed in real time so users have the impression that the image reflected in the display follows every movement they make, including the way the clothes fold and crease.

Anna Hilsmann, one of the Heinrich-Hertz-Institut researchers involved with the clothes mirror, said shoes and clothes are just the first stage for virtual mirror technology. ‘The virtual mirror could also be used to help customers select eyewear or jewellery,’ she said.

Rurainsky said his team is also working on further developments with the shoe-fitting mirror.

For instance, he would like to improve the technology so that when users bend their feet, the virtual image bends with them. At present it can only visualise what a shoe looks like on a foot when it is flat to the floor.

‘We just need to develop the algorithms to do this,’ he said.

Siobhan Wagner