public Builder mergeFrom(com.google.cloud.videointelligence.v1.Track other) {
      if (other == com.google.cloud.videointelligence.v1.Track.getDefaultInstance()) return this;
      if (other.hasSegment()) {
        mergeSegment(other.getSegment());
      }
      if (timestampedObjectsBuilder_ == null) {
        if (!other.timestampedObjects_.isEmpty()) {
          if (timestampedObjects_.isEmpty()) {
            timestampedObjects_ = other.timestampedObjects_;
            bitField0_ = (bitField0_ & ~0x00000002);
          } else {
            ensureTimestampedObjectsIsMutable();
            timestampedObjects_.addAll(other.timestampedObjects_);
          }
          onChanged();
        }
      } else {
        if (!other.timestampedObjects_.isEmpty()) {
          if (timestampedObjectsBuilder_.isEmpty()) {
            timestampedObjectsBuilder_.dispose();
            timestampedObjectsBuilder_ = null;
            timestampedObjects_ = other.timestampedObjects_;
            bitField0_ = (bitField0_ & ~0x00000002);
            timestampedObjectsBuilder_ =
                com.google.protobuf.GeneratedMessageV3.alwaysUseFieldBuilders
                    ? getTimestampedObjectsFieldBuilder()
                    : null;
          } else {
            timestampedObjectsBuilder_.addAllMessages(other.timestampedObjects_);
          }
        }
      }
      if (attributesBuilder_ == null) {
        if (!other.attributes_.isEmpty()) {
          if (attributes_.isEmpty()) {
            attributes_ = other.attributes_;
            bitField0_ = (bitField0_ & ~0x00000004);
          } else {
            ensureAttributesIsMutable();
            attributes_.addAll(other.attributes_);
          }
          onChanged();
        }
      } else {
        if (!other.attributes_.isEmpty()) {
          if (attributesBuilder_.isEmpty()) {
            attributesBuilder_.dispose();
            attributesBuilder_ = null;
            attributes_ = other.attributes_;
            bitField0_ = (bitField0_ & ~0x00000004);
            attributesBuilder_ =
                com.google.protobuf.GeneratedMessageV3.alwaysUseFieldBuilders
                    ? getAttributesFieldBuilder()
                    : null;
          } else {
            attributesBuilder_.addAllMessages(other.attributes_);
          }
        }
      }
      if (other.getConfidence() != 0F) {
        setConfidence(other.getConfidence());
      }
      this.mergeUnknownFields(other.getUnknownFields());
      onChanged();
      return this;
    }
<pre>
A track of an object instance.
</pre>

Protobuf type {@code google.cloud.videointelligence.v1.Track}
java-video-intelligence/proto-google-cloud-video-intelligence-v1/src/main/java/com/google/cloud/videointelligence/v1/Track.java