Create UIImage from raw data.

Demo iOS/ViewController.swift

@@ -106,6 +106,54 @@ class ViewController: UICollectionViewController {
         }
         items.append(effects)
 
+        // Raw Image
+        sections.append("Raw to Image")
+        var raw = [CellItem]()
+        let size = CGSize.init(width: 100, height: 100)
+        // RGBA
+        var rgba: Array<UInt8> = Array.init(repeating: 0, count: Int(size.width * size.height * 4))
+        for y in 0..<Int(size.height) {
+            for x in 0..<Int(size.width) {
+                var r: UInt8 = 0
+                var g: UInt8 = 0
+                var b: UInt8 = 0
+
+                if y > 100 / 3 * 2 {
+                    let unit = UInt(x / 10) * 10
+                    let value = UInt8(Double(unit) / 100.0 * 255)
+                    r = value
+                    g = value
+                    b = value
+                } else {
+                    r = x < 40 ? 255 : 0
+                    g = (x > 20 && x < 80) ? 255 : 0
+                    b = x > 60 ? 255 : 0
+                }
+
+                rgba[(y * Int(size.width) + x) * 4]     = r
+                rgba[(y * Int(size.width) + x) * 4 + 1] = g
+                rgba[(y * Int(size.width) + x) * 4 + 2] = b
+                rgba[(y * Int(size.width) + x) * 4 + 3] = 255
+            }
+        }
+        if let image = UIImage(rgbaBuffer: rgba, size: size) {
+            raw.append(CellItem(text: "RGBA", image: image))
+        }
+
+        // Grayscale
+        var gray: Array<UInt8> = Array.init(repeating: 0, count: Int(size.width * size.height))
+        for y in 0..<Int(size.height) {
+            for x in 0..<Int(size.width) {
+                let unitSize: Int = 20
+                let buf: UInt8 = (((x / unitSize) % 2) != ((y / unitSize) % 2)) == true ? 255 : 0
+                gray[y * Int(size.width) + x] = buf
+            }
+        }
+        if let image = UIImage(grayBuffer: gray, size: size) {
+            raw.append(CellItem(text: "Grayscale", image: image))
+        }
+        items.append(raw)
+
         // Web Image
         sections.append("Web Image")
         var web = [CellItem]()

Sources/ImageHelper.swift

@@ -202,6 +202,83 @@ public extension UIImage {
         UIGraphicsEndImageContext()
     }
 
+    // MARK: Image from raw RGBA data
+    /**
+     Creates a RGB image from raw RGBA.
+
+     - Parameter rgbaData: raw RGBA data
+     - Parameter size: Image size
+
+     - Returns A new image
+     */
+    convenience init?(rgbaBuffer: [UInt8], size: CGSize) {
+        let bitsPerComponent:Int = 8
+        let bitsPerPixel:Int = 32
+        let rgbaSize = 4
+        let bitsPerRow:Int = Int(CGFloat(rgbaSize) * size.width)
+
+        let colorSpace = CGColorSpaceCreateDeviceRGB()
+        let bitmapInfo = CGBitmapInfo(rawValue: CGImageAlphaInfo.premultipliedLast.rawValue)
+        let data = NSData.init(bytes: rgbaBuffer, length: Int(size.width * size.height * CGFloat(rgbaSize)))
+        let provider = CGDataProvider.init(data: data)!
+        let renderingIntent = CGColorRenderingIntent.defaultIntent
+
+        let cgim = CGImage(
+            width: Int(size.width),
+            height: Int(size.height),
+            bitsPerComponent: bitsPerComponent,
+            bitsPerPixel: bitsPerPixel,
+            bytesPerRow: bitsPerRow,
+            space: colorSpace,
+            bitmapInfo: bitmapInfo,
+            provider: provider,
+            decode: nil,
+            shouldInterpolate: true,
+            intent: renderingIntent
+        )
+
+        // Draw it
+        self.init(cgImage:cgim!)
+    }
+
+    // MARK: Image from raw mono data
+    /**
+     Creates a Grayscale image from raw mono.
+
+     - Parameter rgbaData: raw mono data
+     - Parameter size: Image size
+
+     - Returns A new image
+     */
+    convenience init?(grayBuffer: [UInt8], size: CGSize) {
+        let bitsPerComponent:Int = 8
+        let bitsPerPixel:Int = 8
+        let bitsPerRow:Int = Int(size.width)
+
+        let colorSpace = CGColorSpaceCreateDeviceGray()
+        let bitmapInfo = CGBitmapInfo()
+        let data = NSData.init(bytes: grayBuffer, length: Int(size.width * size.height))
+        let provider = CGDataProvider.init(data: data)!
+        let renderingIntent = CGColorRenderingIntent.defaultIntent
+
+        let cgim = CGImage(
+            width: Int(size.width),
+            height: Int(size.height),
+            bitsPerComponent: bitsPerComponent,
+            bitsPerPixel: bitsPerPixel,
+            bytesPerRow: bitsPerRow,
+            space: colorSpace,
+            bitmapInfo: bitmapInfo,
+            provider: provider,
+            decode: nil,
+            shouldInterpolate: true,
+            intent: renderingIntent
+        )
+
+        // Draw it
+        self.init(cgImage:cgim!)
+    }
+
     // MARK: Alpha
     /**
      Returns true if the image has an alpha layer.

_config.yml

@@ -0,0 +1 @@
+theme: jekyll-theme-minimal