public Builder clearRequired() {
        bitField0_ = (bitField0_ & ~0x00000008);
        required_ = false;
        onChanged();
        return this;
      }
<pre>
Whether the current input channel is required by the processor.
For example, for a processor with required video input and optional audio
input, if video input is missing, the application will be rejected while
the audio input can be missing as long as the video input exists.
</pre>

<code>bool required = 3;</code>

@return This builder for chaining.
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/ProcessorIOSpec.java