feat(info.jl): added get_fps

[AbelHo]

function to retrieve video fps

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Codecov Report

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[IanButterworth]

VideoIO.framerate(f) exists, but I notice it is only mentioned in passing in the manual.

Does that meet your needs? If so can you PR to add that to the manual.

Thanks!

[AbelHo]

Thanks for your quick response! VideoIO.framerate(f) gives 1//0 for the videos I have. I hope I am not doing something wrong?

[IanButterworth]

I think it requires that at least one frame has been read. Can you test that?

Perhaps that's fixable

[AbelHo]

The following is what I did:

vid = VideoIO.openvideo("somefile.mp4")
img = read(vid);
VideoIO.framerate(vid)

3 out of 5 video still gives: 1//0

2 out of 5 video successfully give the frame rate after reading one frame

[IanButterworth]

Can you try https://github.com/JuliaIO/VideoIO.jl/pull/393

[AbelHo]

Results from the current master branch before:

julia> VideoIO.framerate.(VideoIO.openvideo.(fnames))
5-element Vector{Rational{Int32}}:
 1//0
 1//0
 1//0
 1//0
 1//0

julia> map(fnames) do x
               vid=VideoIO.openvideo(x); read(vid); VideoIO.framerate(vid)
       end
5-element Vector{Rational{Int32}}:
    1//0
   50//1
 3840//1
    1//0
    1//0

julia> get_fps.(fnames)
5-element Vector{Rational{Int64}}:
 30//1
 25//1
 30//1
 25//1
 25//1

[AbelHo]

Can you try #393

Thank you. tested, added results for both before and after changes, here and in #393 respectively

[IanButterworth]

@AbelHo thanks for the help here. I'm going to close this and try to finish all the framerate fixes over in #393

I'd appreciate your review there as I can't see why tests are failing currently