No headers will be added to the encoded data. This is the same as having selected "ber" in the previous window.

Data will be encoded into blocks of a certain size. If a message would normally be encoded across a block boundary (for a block size of 2048 bytes, this boundary is at offsets 2048, 4096, 8192, ...), the rest of the current block is instead padded out and the message is encoded, starting at the beginning of the next block. Padding bytes are also used to determine whether a block contains more data or is padded out.

Data will be encoded according to the TS 32.297 standard. This includes file and message headers of the standard format.

Custom headers are fixed-length headers that allow data fields within the headers to be specified. Selecting this option will cause an additional dialog to be opened that allows headers and header fields to be declared.

See the section on editing custom headers for details on editing the header format.