public Builder setContrast(double value) {

        contrast_ = value;
        bitField0_ |= 0x00000002;
        onChanged();
        return this;
      }
<pre>
Control black and white contrast of the video. Enter a value between -1
and 1, where -1 is minimum contrast and 1 is maximum contrast. 0 is no
change. The default is 0.
</pre>

<code>double contrast = 2;</code>

@param value The contrast to set.
@return This builder for chaining.
java-video-transcoder/proto-google-cloud-video-transcoder-v1/src/main/java/com/google/cloud/video/transcoder/v1/PreprocessingConfig.java