In this work, we present a new approach which relies on modulating the transmission matrix of the fiber rather than the incident light. We apply computer-controlled mechanical perturbations to the fiber and obtain a desired intensity pattern at its output resulting from. Wavefront shaping in multimode fibers by transmission matrix engineering. APL Photonics, 2020, 5 (3), ⟨10. ⟨hal-02372145⟩ HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific re-search documents, whether they are published or not. The models are first validated by the high.