A modified coding structure, Modulation Array (MA) code, and a novel soft decision method corresponding to MA code are proposed for data processing in digital holographic storage systems. Also developed based on the MA code is a new iterative decoding algorithm, which integrates principles of modulation code detection, soft decision, array code error correction and Turbo code decoding. Experimental results show that when the signal to noise ratio in the channel is low and varying, and the noise parameters are difficult to calculate, this MA code can exploit the information contained in the input data effectively. As long as the raw bit error rate (BER), which is defined as the BER after global optimum threshold quantization, is around 4×10 -2 the output BER of the 8×10 MA code is equivalent to that of traditional 1∶2 modulation code (both codes have the similar code rate). For the raw BER lower than 1×10 -2 the MA code exhibits obvious advantage over the 1∶2 modulation code. Using these techniques, a preliminary experiment has been conducted to store and successfully replay multimedia data including video and audio information.