How to calculate RNA-seq read coverage around STOP codons

Question

[supertech]

I have illumina RNA-seq data from a ligation-based RNA-seq libraries. I need to calculate read coverage per nucleotide around STOP codon (+/- 300 nt or upstream or downstream), with single nucleotide resolution for all human transcriptome (combined mRNAs in single graph, not individually). I am looking for pointers how to do this. Thanks. .