We present a steganographic protocol based on linear error-block codes. Recent works have showed that these codes allow to increase the number of information carrier bits within a given cover by exploiting multiple bit planes (not only LSB plane) from pixels which would not have a perceptible influence on the cover. We employ a parameter, called heterogeneity, to assess the ability of pixels to be modified without perturbing the cover. The quality of the modified cover is handled by tuning a vector of heterogeneity thresholds which determines the number of bit planes that we are allowed to use for each pixel in the cover.