IntermediateControl your volume with hand gestures using Python
Build a gesture volume controller with OpenCV and MediaPipe. Pinch your thumb and index finger together to turn the sound down, spread them apart to turn it up.
Tag
Opencv
Every article tagged Opencv. For a structured path, browse Learn.
AllAiAnnouncementsArchitectureCodingComputer VisionDatabasesDeep LearningErrorsHand TrackingLearningLlmMachine LearningMediapipeNumpyOpencvPandasProductPythonRag
Intermediate
IntermediateReal-time face detection in Python: MediaPipe vs Haar cascade
Two ways to detect faces in a webcam feed with Python. See the code for both, then a straight comparison of speed, accuracy and when each one is the right choice.
IntermediateCount fingers with MediaPipe in Python
Hold up three fingers and Python says three. Learn the landmark logic behind finger counting, including the thumb rule that trips everyone up.
IntermediateBuild an AI push-up counter with pose estimation in Python
Use MediaPipe Pose to measure your elbow angle and count push-up reps automatically. The same state machine works for squats, curls and any repeated movement.
BeginnerExtract text from an image with Python (OCR that actually works)
Tesseract plus a few lines of OpenCV preprocessing turns blurry photos into clean text. Learn the cleanup steps that take accuracy from unusable to reliable.
BeginnerModuleNotFoundError: No module named 'cv2' — how to fix it
Python cannot find OpenCV because the package was installed into a different Python than the one running your script. Here is how to find the right Python and fix it in under five minutes.
BeginnerTypeError: 'NoneType' object is not subscriptable — the debug recipe
This error means a function handed you None and you tried to index it. Learn the three functions that return None most often and the two-line guard that fixes them.
IntermediateBuild a Virtual Mouse with OpenCV and MediaPipe in Python
Learn how to build a virtual mouse in Python using OpenCV and MediaPipe hand tracking. Move the cursor with your index finger and click with a pinch — beginner-friendly step-by-step tutorial.