A three-dimensional measurement system includes a projector 102, a camera 103, and a PC 101 which obtains distance information from images captured by the camera 103. Further, the three-dimensional measurement system includes a synchronization control apparatus 104 connected to the PC 101 via a video output I/F 105 and a video input I/F 108, to the projector 102 via a video output I/F 102, and to the camera 103 via the video input I/F 107. The synchronization control apparatus 104 performs synchronization control of the projector 102 and the camera 103 based on an instruction from the PC 101. Further, the synchronization control apparatus 104 detects an error, embeds the error information in the captured image input from the video input I/F 107, and outputs the processed captured image to the PC 101 via the video input I/F 108.