Scanning techniques combining laser line projection with motion are simple and efficient. But there are number of cases in which laser triangulation fails. Some have well known solutions. Other, like adverse illumination by intense white light or presence of textures make laser projection hard to distinguish, and have no specific solution. In this article, a method is presented to improve retrieving laser projection for those cases. It’s build upon two main ideas. First, using auxiliary lines to create local high frequencies. Second, Transform a high speed camera in an intensity modulation receiver. The principle is to send a periodic message in the lines intensity and try to track traces of a spatial-temporal deforming pattern in the video sequences produced by the camera. It permits two main improvements. First, when adverse illumination produce other lines, they can be discriminate by the fact they don’t send the message. Second, when adverse illumination produce a highly luminous image or when a texture diffuse a part of the laser energy, it’s sufficient to track the noise of the message. By choosing a message, it’s possible to create every type of noise in order to distinguish it between the rest of image noises.