Negative pixel compensation in a touch sensor panel is disclosed. The panel can compensate for a negative pixel effect in touch signal outputs due to poor grounding of an object touching the panel. To do so, the panel can reconstruct a captured touch image to remove negative pixel values indicative of the negative pixel effect and compute a composite image from the captured image and the reconstructed image to replace the captured image. In addition or alternatively, the panel can reconstruct a captured touch image to remove negative pixel values indicative of the negative pixel effect and replace the captured image with the reconstructed image.