A pickup apparatus, comprising: a digital signal processor, at least one microphone, multiple amplifiers, and multiple analog-to-digital converters, wherein the multiple amplifiers are in a one-to-one correspondence with the multiple analog-to-digital converters, each amplifier in the multiple amplifiers is corresponding to one microphone in the at least one microphone, and at least two amplifiers that have different gain values from each other and that are in the multiple amplifiers are corresponding to a same microphone in the at least one microphone, wherein the microphone is configured to: receive an audio signal, and send the audio signal to an amplifier corresponding to each microphone; the amplifiers are configured to: amplify the received audio signal to obtain the amplified audio signal, and send the amplified audio signal to an analog-to-digital converter corresponding to each amplifier; the analog-to-digital converter is configured to: convert the received audio signal into a digital signal, and send the digital signal to the digital signal processor; and the digital signal processor is configured to: receive multiple digital signals sent by the multiple analog-to-digital converters, determine an unclipped digital signal from the multiple received digital signals, and determine an output signal according to a gain value corresponding to the unclipped digital signal; wherein the at least one microphone comprises at least two microphones called a fourth microphone and a fifth microphone, and the fourth microphone and the fifth microphone have a same physical parameter; and that at least two amplifiers that have different gain values from each other and that are in the multiple amplifiers are corresponding to a same microphone in the at least one microphone comprises: N second amplifiers that have different gain values from each other and that are in the multiple amplifiers are corresponding to the fourth microphone, and N third amplifiers that have different gain values from each other and that are in the multiple amplifiers are corresponding to the fifth microphone, wherein the N second amplifiers and the N third amplifiers constitute N amplifier pairs, each amplifier pair in the N amplifier pairs comprises one second amplifier and one third amplifier that have a same gain value, and N is an integer greater than 1; wherein the digital signal processor is specifically configured to: perform audio mixing on digital signal pairs in the multiple received digital signals to obtain optimized digital signals, wherein the digital signal pairs are constituted of digital signals respectively corresponding to a second amplifier and a third amplifier that are comprised in an amplifier pair, and the N amplifier pairs comprise the amplifier pair; determine an unclipped digital signal from a digital signal set that is constituted of the optimized digital signals; and determine, as an output signal, a digital signal that is corresponding to a maximum gain value and that is in the unclipped digital signal. N second amplifiers that have different gain values from each other and that are in the multiple amplifiers are corresponding to the fourth microphone, and N third amplifiers that have different gain values from each other and that are in the multiple amplifiers are corresponding to the fifth microphone, wherein the N second amplifiers and the N third amplifiers constitute N amplifier pairs, each amplifier pair in the N amplifier pairs comprises one second amplifier and one third amplifier that have a same gain value, and N is an integer greater than 1; wherein the digital signal processor is specifically configured to: perform audio mixing on digital signal pairs in the multiple received digital signals to obtain optimized digital signals, wherein the digital signal pairs are constituted of digital signals respectively corresponding to a second amplifier and a third amplifier that are comprised in an amplifier pair, and the N amplifier pairs comprise the amplifier pair; determine an unclipped digital signal from a digital signal set that is constituted of the optimized digital signals; and determine, as an output signal, a digital signal that is corresponding to a maximum gain value and that is in the unclipped digital signal. perform audio mixing on digital signal pairs in the multiple received digital signals to obtain optimized digital signals, wherein the digital signal pairs are constituted of digital signals respectively corresponding to a second amplifier and a third amplifier that are comprised in an amplifier pair, and the N amplifier pairs comprise the amplifier pair; determine an unclipped digital signal from a digital signal set that is constituted of the optimized digital signals; and determine, as an output signal, a digital signal that is corresponding to a maximum gain value and that is in the unclipped digital signal.