Stuck on an issue?

Lightrun Answers was designed to reduce the constant googling that comes with debugging 3rd party libraries. It collects links to all the places you might be looking at while hunting down a tough bug.

And, if you’re still stuck at the end, we’re happy to hop on a call to see how we can help out.

`VideoCapture.Open()` is significantly slower on x64 as compared to x86.

See original GitHub issue

Summary of your issue

VideoCapture.Open() is significantly slower on x64 as compared to x86. x64: 5 to 10 seconds x86: 1 to 2 seconds

I noticed this issue was raised but there wasn’t a solution.

Environment

OpenCvSharp-4.5.3-20210821 .NET Framework 4.7.2 Windows 10 64-bit

What did you do when you faced the problem?

I ran the sample project provided (Added a x64 configuration).

\Sample-4.5.3-20210821\VideoCaptureForm

Example code:

paste your core code

Output:

paste your output

What did you intend to be?

Issue Analytics

State:
Created 2 years ago
Reactions:1
Comments:5

Top GitHub Comments

3reactions

bryansiebertcommented, Feb 21, 2022

It seems to be this issue opencv/opencv#17687 Adding Environment.SetEnvironmentVariable("OPENCV_VIDEOIO_MSMF_ENABLE_HW_TRANSFORMS", "0"); will fix it. Using VideoCapturesAPIs.DSHOW also works but it gave me a much choppier stream

1reaction

Timocopcommented, Nov 10, 2021

What Capture API do you use? You haven’t posted any sample code to reproduce. But i also noticed that - when getting webcam streams - camera.Set(OpenCvSharp.VideoCaptureProperties.FourCC, OpenCvSharp.VideoWriter.FourCC("MJPG")) and VideoCaptureAPIs.MSMF takes a very long time to load (10 seconds) compared to VideoCapturesAPIs.DSHOW which loads instantly. Set the Capture API manually, instead of VideoCaptureAPIs.ANY. This will also remove weird webcam artifacts!