Unit 4: Camera Interfacing & Computer Vision - Practice Quiz

1 Which component connects a Raspberry Pi camera module to the Raspberry Pi board?

2 What is the main purpose of the image sensor in a camera module?

3 Before connecting a Raspberry Pi camera ribbon cable, what should usually be done?

4 Which part of the Raspberry Pi camera cable must be aligned correctly with the connector?

5 Which software feature may need to be enabled before using a Raspberry Pi camera?

6 What does ISP commonly stand for in a camera system?

7 Which task is commonly performed by an image signal processor?

8 What is the usual first source of data in a digital camera pipeline?

9 What is the purpose of converting raw camera data into a processed image?

10 What is OpenCV mainly used for?

11 Which Python package name is commonly used to install OpenCV?

12 Which Python statement commonly imports OpenCV?

13 Why might an image be converted to grayscale before processing?

14 What does resizing an image change?

15 Which operation can help reduce small amounts of image noise?

16 What is the goal of face detection?

17 How is face recognition different from face detection?

18 What does an object detection model usually provide for an object in an image?

19 What is a bounding box in object detection?

20 What does video streaming over a network allow a user to do?

21 Which interface normally carries image data from an official Raspberry Pi camera module to the Raspberry Pi processor?

22 A fast-moving fan appears tilted in images captured by a Raspberry Pi camera with a rolling-shutter sensor. What is the most likely cause?

23 After connecting a camera to a recent Raspberry Pi OS installation, which command is most suitable for quickly verifying that the camera can capture a preview?

24 A CSI camera is not detected immediately after its ribbon cable was reconnected. What should be checked first?

25 What is the main purpose of the demosaicing stage in a camera image signal processor?

26 A camera produces dark frames with little motion blur. Which adjustment is most appropriate if additional image noise is acceptable?

27 Under white indoor lighting, a white object appears yellow in the captured image. Which ISP operation should primarily correct this effect?

28 An OpenCV frame appears blue where red is expected after being displayed with a library that expects RGB data. Which conversion should be applied?

29 A Python camera program exits, but the camera remains unavailable to another process for a short time. Which OpenCV action helps prevent this problem?

30 A program receives a valid frame from cv2.VideoCapture, but cv2.imshow() appears frozen because the event loop is not processed. Which call is needed inside the display loop?

31 An image of size must be resized to a width of while preserving its aspect ratio. What should the new height be?

32 A grayscale image has poor contrast in some regions, while other regions already have acceptable contrast. Which technique is most suitable for local enhancement without strongly amplifying noise?

33 A Canny edge detector produces many false edges because the input image contains sensor noise. Which preprocessing step is most appropriate?

34 A face detector is missing several partially visible faces. Lowering its detection threshold is likely to produce which result?

35 A face-recognition system represents each face as an embedding vector. How is a newly captured face commonly identified?

36 A recognition system works for frontal faces but performs poorly when faces are tilted. Which preprocessing step is most likely to improve consistency?

37 A detector produces several highly overlapping boxes for the same object. Which post-processing method should be applied?

38 An object-detection model expects a square input, but the camera frame is widescreen. Which preprocessing method best preserves object shapes?

39 A Raspberry Pi object detector is accurate but too slow for the required frame rate. Which change is most likely to improve speed while retaining the same general task?

40 An MJPEG stream sends JPEG frames per second, and each frame averages KB. Approximately what application-level bandwidth is required?

41 A Raspberry Pi camera is connected through the CSI interface, while image processing is performed largely by the SoC multimedia subsystem. Which consequence is most important when diagnosing a high-resolution capture failure?

42 A rolling-shutter Raspberry Pi camera observes a rapidly rotating fan. Which artifact is most likely, and which architectural property explains it?

43 A camera application must provide a low-latency preview and periodically save high-quality still images. Which design best uses the camera architecture?

44 After physically connecting a camera, the preview command reports that no camera is detected. Which diagnostic sequence is most appropriate?

45 A camera works at 640x480 but fails at its advertised maximum resolution. Which explanation is most technically defensible?

46 A manually focused camera produces sharp images at close range but blurred images for distant objects. Which adjustment is most appropriate?

47 Why can a raw Bayer frame appear strongly tinted when opened directly as if it were an ordinary RGB image?

48 An image has correct brightness but a strong blue cast under warm indoor lighting. Which ISP operation primarily addresses this problem?

49 A scene contains a bright window and a dark indoor subject. Why might enabling HDR or multi-exposure processing improve the subject while introducing motion artifacts?

50 An OpenCV application reports that the camera backend opens successfully but returns empty frames intermittently. Which first change best isolates the cause?

51 A script works in a system Python shell but fails inside a virtual environment with an import error for OpenCV. What is the most likely cause?

52 A BGR frame from OpenCV is passed directly to a model trained with RGB images. The model's confidence decreases substantially. Which correction is required?

53 A grayscale image has poor global contrast because most pixels occupy a narrow intensity interval, but illumination varies across the scene. Which method is generally most suitable?

54 A face detector misses small faces after an image is resized for speed. Which change most directly addresses the recall problem while controlling computational cost?

55 An edge detector produces many false edges in a low-light image. Which preprocessing choice is most likely to reduce false responses without eliminating all object boundaries?

56 A recognition system performs well on enrollment images but confuses people under different lighting and head poses. Which redesign best separates detection from recognition concerns?

57 A face-recognition system must reject unknown people, but its nearest-neighbor classifier always assigns the closest enrolled identity. What change is necessary?

58 A detector produces multiple overlapping boxes for one object. Which post-processing operation is intended to retain the strongest box while suppressing redundant detections?

59 A model trained on 640x640 letterboxed images receives a 1280x720 frame. Which preprocessing error is most likely to corrupt predicted box coordinates?

60 A Raspberry Pi streams video over Wi-Fi. Viewers observe increasing delay even though the displayed video remains smooth. Which change most directly limits latency growth?