A speech compression apparatus including: a first band-transform unit
transforming a wideband speech signal to a narrowband low-band speech
signal; a narrowband speech compressor compressing the narrowband
low-band speech signal and outputting a result of the compressing as a
low-band speech packet; a decompression unit decompressing the low-band
speech packet and obtaining a decompressed wideband low-band speech
signal; an error detection unit detecting an error signal that
corresponds to a difference between the wideband speech signal and the
decompressed wideband low-band speech signal; and a high-band speech
compression unit compressing the error signal and a high-band speech
signal of the wideband speech signal and outputting the result of the
compressing as a high-band speech packet.