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OpenCV/cv2 Functions

See vidformer.cv2 API docs.

cv2 showcase

Legend:

  • ✅ - Support
  • 🔸 - Support via OpenCV cv2
  • ❌ - Not yet implemented

Vidformer-specific Functions

  • cv2.vidplay(video) - Play a VideoWriter, Spec, or Source
  • VideoWriter.spec() - Return the Spec of an output video
  • Frame.numpy() - Return the frame as a numpy array
  • cv2.setTo - The OpenCV Mat.setTo function (not in cv2)
  • cv2.zeros - Create a black frame (equivalent to numpy.zeros)

opencv

ClassStatus
VideoCapture✅
VideoWriter✅
VideoWriter_fourcc✅
FunctionStatus
imread✅
imwrite✅

opencv.imgproc

Drawing Functions:

FunctionStatus
arrowedLine✅
circle✅
clipLine🔸
drawContours✅
drawMarker✅
ellipse✅
ellipse2Poly🔸
fillConvexPoly✅
fillPoly✅
getFontScaleFromHeight🔸
getTextSize🔸
line✅
polylines✅
putText✅
rectangle✅

opencv.core

FunctionStatus
addWeighted✅
copyMakeBorder✅
flip✅
hconcat✅
resize✅
rotate✅
vconcat✅

Output Comparison

Vidformer’s cv2 output compared to native OpenCV (source code):

Vidformer:

Vidformer cv2 output

OpenCV:

OpenCV output

Per-pixel Diff:

Difference between outputs

The differences mainly come from Vidformer using FFmpeg’s swscale for resize instead of OpenCV’s resize.