! @function
@abstract Get query sequence
@param b pointer to an alignment
@return pointer to sequence
@discussion Each base is encoded in 4 bits: 1 for A, 2 for C, 4 for G,
8 for T and 15 for N. Two bases are packed in one byte with the base
at the higher 4 bits having smaller coordinate on the read. It is
recommended to use bam_seqi() macro to get the base.
! @function @abstract Get query sequence @param b pointer to an alignment @return pointer to sequence
@discussion Each base is encoded in 4 bits: 1 for A, 2 for C, 4 for G, 8 for T and 15 for N. Two bases are packed in one byte with the base at the higher 4 bits having smaller coordinate on the read. It is recommended to use bam_seqi() macro to get the base.