Live filtering with slider

[agruchala]

Is there an option to change filter values in fly, with slider or other control?

[Silence-GitHub]

For camera and video, just change the filter value.

contrastFilter.contrast = slider.value

For static image, change the filter value and transmit texture.

contrastFilter.contrast = slider.value
imageSource.transmitTexture()

[niraj547]

Hi It's not working, what I was doing wrong??

@objc func sliderValueDidChange(_ sender:UISlider!){
        let roundedStepValue = Float(round(sender.value / step) * step)
        sender.value = roundedStepValue

        var contrastFilter = BBMetalContrastFilter(contrast: roundedStepValue)
        contrastFilter.contrast = roundedStepValue

        if let filter = self.filter {
           camera.add(consumer: filter).add(consumer: filterView)
            filter.add(consumer: videoWriter)
            if let source = imageSource {
                camera.willTransmitTexture = { [weak self] _, _ in
                    guard self != nil else { return }
                    source.transmitTexture()
                }
                source.add(consumer: filter)
            }

        } else {
            camera.add(consumer: filterView)
            camera.willTransmitTexture = nil
            imageSource = nil
            camera.add(consumer: videoWriter)

        }

    }

[Silence-GitHub]

@niraj547 Hi, the problem is the contrastFilter (local variable) is not in the filter chain.

Set up filter chain before changing the slider value. When changing the slider value, do not change the filter chain. Please try the code below.

// Call this function before changing the slider value
func setupFilterChain() {
    if let filter = self.filter {
        camera.add(consumer: filter).add(consumer: filterView)
        ...
    } else {
        camera.add(consumer: filterView)
        ...
    }
}

@objc func sliderValueDidChange(_ sender:UISlider!) {
    self.filter.contrast = ...
}

[niraj547]

Hi It doesn't work and also I think I have multiple filter buttons and each of them has a slider, doing this freeze the whole screen that might be the reason?

Also 1 quick question can we chain multiple filters in a single video recording or do I have to join all the video after each filter has been applied?? For example: filter1 applied 32sec + filter2 applied 32sec = final Video something like this

Sorry for asking a dumb question, I'm really new in ios Thanks