  Optical imaging through scattering media is a fundamental challenge in many
applications. Recently, substantial breakthroughs such as imaging through
biological tissues and looking around corners have been obtained by the use of
wavefront-shaping approaches. However, these require an implanted guide-star
for determining the wavefront correction, controlled coherent illumination, and
most often raster scanning of the shaped focus. Alternative novel computational
approaches that exploit speckle correlations, avoid guide-stars and wavefront
control but are limited to small two-dimensional objects contained within the
memory-effect correlations range. Here, we present a new concept, image-guided
wavefront-shaping, allowing non-invasive, guidestar-free, widefield, incoherent
imaging through highly scattering layers, without illumination control. Most
importantly, the wavefront-correction is found even for objects that are larger
than the memory-effect range, by blindly optimizing image-quality metrics. We
demonstrate imaging of extended objects through highly-scattering layers and
multi-core fibers, paving the way for non-invasive imaging in various
applications, from microscopy to endoscopy.
