A simplified signal-transform technique is utilized to map the output pulse temporal waveform into the spectral response of the shaper or coder. By designing the apodization profile of linearly chirped-fiber-Bragg-grating, a transform-limit Gaussian ultrashort optical pulse is shaped into a rectangular or triangular temporal output waveform. In addition, in order to demonstrate the feasibility for coding a train of optical pulses, non-return-zero(NRZ) or return-zero (RZ) pulse with 1011 codes are generated.