Repository: opencv
Issue:  cv::findDecoder imread_: can't open/read file: check file path/integrity
Labels: question (invalid tracker)

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##### System information (version)
<!-- Example
- OpenCV => 4.2
- Operating System / Platform => Windows 64 Bit
- Compiler => Visual Studio 2017
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- OpenCV => 4.5.5
- Operating System / Platform => Windows 64 Bit/Anaconda 4.1.2
- Compiler => Spyder/anaconda prompt

##### Detailed description
Opencv doesnt open videos. It works normally with static images, but cv2.VideoCapture() fails.
The error:
[ WARN:0@0.211] global C:\build\master_winpack-build-win64-vc15\opencv\modules\imgcodecs\src\loadsave.cpp (239) cv::findDecoder imread_('cinto.mp4'): can't open/read file: check file path/integrity

where 'cinto.mp4' is the file i'm trying to read.
The problem is not with the file or the file location as i'm running the code in the same path as the video.
<!-- your description -->

##### Steps to reproduce

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    ```.cpp
    // C++ code example
    ```
 or attach as .txt or .zip file
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```.py
  import cv2
  file_name = 'cinto.mp4'
  vcap = cv2.VideoCapture(file_name)
  if vcap.isOpened():
    width  = int(vcap.get(cv2.CAP_PROP_FRAME_WIDTH))   # float `width`
    height = int(vcap.get(cv2.CAP_PROP_FRAME_HEIGHT))  # float `height`
    fps =  vcap.get(cv2.CAP_PROP_FPS)
  else:
    print("Error opening the video")
    return -1
 ```
The code above prints:
Error opening the video

[ WARN:0@0.211] global C:\build\master_winpack-build-win64-vc15\opencv\modules\imgcodecs\src\loadsave.cpp (239) cv::findDecoder imread_('cinto.mp4'): can't open/read file: check file path/integrity

I tried to install opencv with conda and couldn't, so i tried with opencv version. I also tried with the Windows Release downloaded in https://opencv.org/releases/

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 - [X] There is reproducer code and related data files: videos, images, onnx, etc
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