How to use the slider to change frames?

Question

I'm guessing that the slider's max value needs to be set to the total number of frames in the video, and that we need to use the slider's value to find the frame but I have no idea how to do it.

Comments

Instead of setting the slider's max value to the total number of frames as you said, you could also consider these 3 values to compute the % of your "point" in the slider that corresponds to % length of the video :

1. newValue.doubleValue() represents the new value in the slider (where you
   changed it)
2. sliderSeekBar.getMax() represents the total value of the slider (usually returns 100 by default)
3. capture.get(Videoio.CV_CAP_PROP_FRAME_COUNT) that tells you the number of actual frames in the video

Answer 1

Good point. You can do this with:

vidCap.get(Videoio.CV_CAP_PROP_FRAME_COUNT);

where vidCap is an opencv VideoCapture object.

Answer 2

I also use these to set the value that the slider bar represents:
sliderSeekBar.setMax();
sliderSeekBar.setWidthMax();

those 2 look the same and I don't know for sure if one of them is unnecessary, but when removed the sliderSeekBar.setWidthMax, it didn't work.

Comments

is sliderSeekBar the name of your Slider object?

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yes it is! sorry for not clarifying that.

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What computation did you have using both sliderSeekBar.setMax(); and sliderSeekBar.setWidthMax();?