Trellisstructuresofblockcodesarediscussed.L-sectiontrellisstructuresofsomeBCHcodesarepresented.AfastmaximumlikelihooddecodingalgorithmforBCHcodesisproposedcorrespondingly,thedecodingproblemofq-aryimagesofqm-aryblockcodesisalsodiscussed.Thedirect-sumpartitionandtheassociateddecodingalgorithmsaregivenfortheimages.
