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@liufsd
Created September 19, 2018 15:57
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UIImage Pixel
extension UIImage {
func maxArea() -> CGRect{
let provider = self.cgImage!.dataProvider
let providerData = provider!.data
let data = CFDataGetBytePtr(providerData)
var minX = 0
var minY = 0
var maxX = 0
var maxY = 0
for row in 0..<Int(self.size.height) {
for col in 0..<Int(self.size.width) {
let numberOfComponents = 4
let pixelData = ((Int(size.width) * row) + col) * numberOfComponents
let r = CGFloat(data![pixelData]) / 255.0
let g = CGFloat(data![pixelData + 1]) / 255.0
let b = CGFloat(data![pixelData + 2]) / 255.0
let a = CGFloat(data![pixelData + 3]) / 255.0
if r != 0 || g != 0 || b != 0 || a != 0 {
if r == 1 && g == 1 && b == 1 && a == 1 {
continue
} else {
if row >= maxY {
maxY = row
}
if row <= minY {
minY = row
}
if col >= maxX {
maxX = col
}
if col <= minX {
minX = col
}
}
}
}
}
return CGRect(x: minX, y: minY, width: maxX - minX, height: maxY - minY)
}
func pixelData() -> [Pixel] {
let provider = self.cgImage!.dataProvider
let providerData = provider!.data
let data = CFDataGetBytePtr(providerData)
var r, g, b, a: UInt8
var pixels: [Pixel] = []
for row in 0..<Int(self.size.height) {
for col in 0..<Int(self.size.width) {
// r = data.memory
// data = data?.advancedBy(1)
// g = data.memory
// data = data.advancedBy(1)
// b = data.memory
// data = data.advancedBy(1)
// a = data.memory
// data = data.advancedBy(1)
// pixels.append(Pixel(r: r, g: g, b: b, a: a, row: row, col: col))
let numberOfComponents = 4
let pixelData = ((Int(size.width) * col) + row) * numberOfComponents
let r = CGFloat(data![pixelData]) / 255.0
let g = CGFloat(data![pixelData + 1]) / 255.0
let b = CGFloat(data![pixelData + 2]) / 255.0
let a = CGFloat(data![pixelData + 3]) / 255.0
pixels.append(Pixel(r: UInt8(r), g: UInt8(g), b: UInt8(b), a: UInt8(a), row: row, col: col))
}
}
return pixels
}
}
struct Pixel {
var r: Float
var g: Float
var b: Float
var a: Float
var row: Int
var col: Int
init(r: UInt8, g: UInt8, b: UInt8, a: UInt8, row: Int, col: Int) {
self.r = Float(r)
self.g = Float(g)
self.b = Float(b)
self.a = Float(a)
self.row = row
self.col = col
}
var color: UIColor {
return UIColor(red: CGFloat(r/255.0), green: CGFloat(g/255.0), blue: CGFloat(b/255.0), alpha: CGFloat(a/255.0))
}
var description: String {
return "RGBA(\(r), \(g), \(b), \(a))"
}
}
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