Aiming at the problems of halo and artifacts caused by minimum filtering as well as sky distortion caused by insufficient transmittance estimation, one dehazing algorithm is proposed, which is based on quadratic constraints and haze distributions. Firstly, the Canny detection operator is used to obtain the coarse texture distributions of hazy images, and the mist distribution maps of hazy images are obtained on the basis of scene depth. Second, according to the image characteristics, a quadratic constrain model based on adaptive haze coefficients is proposed to estimate the minimum channel of clear images, and the atmospheric scattering model is used to obtain rough transmittance. Third, the transmittance is optimized through adaptive lower boundary constraints and bilateral filtering, and local atmospheric light is improved through morphological operations. Finally, the dehazing images are obtained according to the restoration model. Experiments show that the proposed algorithm has achieved ideal results in both subjective and objective evaluations, and it can better solve the problems including halos, artifacts, and sky distortion in dehazing images.