Files
RoundCode/Sources/Internal/RCImageDecoder.swift
T

238 lines
12 KiB
Swift

// MIT License
// Copyright (c) 2020 Haik Aslanyan
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
import UIKit
import CoreImage
final class RCImageDecoder {
private var context = CIContext()
func process(pointer: UnsafeMutablePointer<UInt8>, size: Int) throws -> [RCBit] {
let bufferData = UnsafeMutableBufferPointer<UInt8>(start: pointer, count: size * size)
let data = RCMatrix<UInt8>(rows: size, items: bufferData)
let sectionSize = size / 5
let sectors = Side.allCases.map { side -> (side: Side, x: Int, y: Int) in
switch side {
case .top:
let x = (size - sectionSize) / 2
let y = 0
return (side, x, y)
case .bottom:
let x = (size - sectionSize) / 2
let y = size - sectionSize
return (side, x, y)
case .left:
let x = 0
let y = (size - sectionSize) / 2
return (side, x, y)
case .right:
let x = size - sectionSize
let y = (size - sectionSize) / 2
return (side, x, y)
}
}
var points = [CGPoint]()
for sector in sectors {
let point = try scanControlPoint(region: (sector.x, sector.y, sectionSize), data: data, side: sector.side)
points.append(point)
}
print(points)
let image = try fixPerspective(pointer, points: points, size: size)
let bits = decode(image)
return bits
}
func decode(_ image: UIImage) throws -> [RCBit] {
let size = image.cgImage!.height
var pixelData = UnsafeMutableRawPointer.allocate(byteCount: size * size, alignment: MemoryLayout<UInt8>.alignment)
let context = CGContext(data: pixelData, width: size, height: size, bitsPerComponent: 8, bytesPerRow: size, space: CGColorSpaceCreateDeviceGray(), bitmapInfo: CGImageAlphaInfo.none.rawValue)
context?.draw(image.cgImage!, in: CGRect(origin: .zero, size: CGSize(width: size, height: size)))
defer {
pixelData.deallocate()
}
let bits = try process(pointer: pixelData.assumingMemoryBound(to: UInt8.self), size: size)
return bits
}
}
extension RCImageDecoder {
private func scanControlPoint(region: (x: Int, y: Int, size: Int), data: RCMatrix<UInt8>, side: Side) throws -> CGPoint {
var points = [CGPoint]()
var lastPattern = RCPixelPattern(bit: data[region.x, region.y] > 180 ? RCBit.zero : RCBit.one, row: region.y, column: region.x, count: 0)
var pixelPatterns = [lastPattern]
var count = 0
let maxSize = region.size * region.size
while count < maxSize {
let rowIndex = count / region.size + region.y
let columnIndex = count % region.size + region.x
let bit = data[columnIndex, rowIndex] > 180 ? RCBit.zero : RCBit.one
if lastPattern.row == rowIndex, lastPattern.bit == bit {
lastPattern.count += 1
pixelPatterns[pixelPatterns.count - 1] = lastPattern
} else {
lastPattern = RCPixelPattern(bit: bit, row: rowIndex, column: columnIndex, count: 1)
pixelPatterns.append(lastPattern)
}
count += 1
}
let pixelPatternsBuffer = UnsafeMutableBufferPointer(start: UnsafeMutableRawPointer(mutating: pixelPatterns).assumingMemoryBound(to: RCPixelPattern.self), count: pixelPatterns.count)
// NotificationCenter.default.post(name: NSNotification.Name.init("random"), object: pixelPatterns)
guard pixelPatternsBuffer.count >= 5 else { throw RCError.decoding }
var countIndex = 0
while countIndex < pixelPatternsBuffer.count - 5 {
let pattern1 = pixelPatternsBuffer[countIndex]
let pattern2 = pixelPatternsBuffer[countIndex + 1]
let pattern3 = pixelPatternsBuffer[countIndex + 2]
let pattern4 = pixelPatternsBuffer[countIndex + 3]
let pattern5 = pixelPatternsBuffer[countIndex + 4]
countIndex += 1
guard pattern3.count >= 10 else { continue }
let row = pattern1.row
guard pattern2.row == row, pattern3.row == row, pattern4.row == row, pattern5.row == row else { continue }
guard pattern1.bit == .one, pattern2.bit == .zero, pattern3.bit == .one, pattern4.bit == .zero, pattern5.bit == .one else { continue }
guard RCConstants.dotPointRange.contains(pattern3.count / pattern1.count) else { continue }
guard RCConstants.dotPointRange.contains(pattern3.count / pattern2.count) else { continue }
guard RCConstants.dotPointRange.contains(pattern3.count / pattern4.count) else { continue }
guard RCConstants.dotPointRange.contains(pattern3.count / pattern5.count) else { continue }
switch side {
case .left:
points.append(CGPoint(x: pattern1.column, y: pattern1.row))
case .right:
points.append(CGPoint(x: CGFloat(pattern5.column) + CGFloat(pattern5.count), y: CGFloat(pattern5.row)))
case .top:
let distance = (CGFloat(pattern5.column) + CGFloat(pattern5.count) - CGFloat(pattern1.column)) / 2
let centerX = CGFloat(pattern1.column) + distance
let centerY = CGFloat(row) - distance
points.append(CGPoint(x: centerX, y: centerY))
case .bottom:
let distance = (CGFloat(pattern5.column) + CGFloat(pattern5.count) - CGFloat(pattern1.column)) / 2
let centerX = CGFloat(pattern1.column) + distance
let centerY = CGFloat(row) + distance
points.append(CGPoint(x: centerX, y: centerY))
}
}
guard !points.isEmpty else { throw RCError.decoding }
switch side {
case .left:
return points.sorted(by: {$0.x < $1.x}).first!
case .right:
return points.sorted(by: {$0.x > $1.x}).first!
case .top:
return points.sorted(by: {$0.y < $1.y}).first!
case .bottom:
return points.sorted(by: {$0.y > $1.y}).first!
}
}
private func fixPerspective(_ data: UnsafeMutablePointer<UInt8>, points: [CGPoint], size: Int) throws -> CGImage {
let data = CFDataCreate(nil, data, size * size)!
let provider = CGDataProvider(data: data)!
let cgImage = CGImage(width: size, height: size, bitsPerComponent: 8, bitsPerPixel: 8, bytesPerRow: size, space: CGColorSpaceCreateDeviceGray(), bitmapInfo: CGBitmapInfo(rawValue: 0), provider: provider, decode: nil, shouldInterpolate: true, intent: CGColorRenderingIntent.defaultIntent)!
// let path = UIBezierPath()
// path.move(to: points[0])
// path.addLine(to: points[1])
// path.addLine(to: points[2])
// path.addLine(to: points[3])
// path.close()
// let originalBounds = path.bounds
// path.apply(CGAffineTransform(scaleX: sqrt(2.0), y: sqrt(2.0)))
// let scaledBounds = path.bounds
// path.apply(CGAffineTransform(translationX: (originalBounds.width - scaledBounds.width) / 2 , y: (originalBounds.height - scaledBounds.height) / 2))
// let vectors = points.map{CGVector(dx: $0.x, dy: $0.y)}
// let image = CIImage() //.image(from: data)
// let perspectiveFilter = CIFilter(name: "CIPerspectiveCorrection")!
// perspectiveFilter.setValue(image, forKey: "inputImage")
// perspectiveFilter.setValue(vectors[0], forKey: "inputTopLeft")
// perspectiveFilter.setValue(vectors[1], forKey: "inputTopRight")
// perspectiveFilter.setValue(vectors[2], forKey: "inputBottomRight")
// perspectiveFilter.setValue(vectors[3], forKey: "inputBottomLeft")
// let transform = CGAffineTransform(translationX: image.extent.midX, y: image.extent.midY).rotated(by: CGFloat.pi / 4).translatedBy(x: -image.extent.midX, y: -image.extent.midY)
// let correctedImage = perspectiveFilter.outputImage!.transformed(by: transform)
// let cgImage = context.createCGImage(correctedImage, from: CGRect(x: 0, y: 0, width: data.columns, height: data.columns))!
// var pixelValues = UnsafeMutableRawPointer.allocate(byteCount: cgImage.width * cgImage.height, alignment: MemoryLayout<UInt8>.alignment)
// let colorSpace = CGColorSpaceCreateDeviceGray()
// let contextRef = CGContext(data: &pixelValues, width: cgImage.width, height: cgImage.height, bitsPerComponent: 8, bytesPerRow: cgImage.width, space: colorSpace, bitmapInfo: 0)
// contextRef?.draw(cgImage, in: CGRect(origin: .zero, size: CGSize(width: cgImage.width, height: cgImage.height)))
// data.data.deallocate()
// data.data = UnsafeMutableBufferPointer<UInt8>(start: pixelValues.bindMemory(to: UInt8.self, capacity: data.columns * data.rows), count: data.columns * data.rows)
// return data
throw RCError.decoding
// return UIImage().cgImage!
}
private func decode(_ image: CGImage) -> [RCBit] {
let pixelData = UnsafeMutableRawPointer.allocate(byteCount: image.width * image.height, alignment: MemoryLayout<UInt8>.alignment)
let context = CGContext(data: pixelData, width: image.width, height: image.height, bitsPerComponent: 8, bytesPerRow: image.width, space: CGColorSpaceCreateDeviceGray(), bitmapInfo: CGImageAlphaInfo.none.rawValue)
context?.draw(image, in: CGRect(origin: .zero, size: CGSize(width: image.width, height: image.height)))
let buffer = UnsafeMutableBufferPointer<UInt8>(start: pixelData.assumingMemoryBound(to: UInt8.self), count: image.width * image.height)
let data = RCMatrix(rows: image.height, items: buffer)
let size = CGFloat(data.columns)
let lineWidth = size * RCConstants.dotSizeScale / 11 * 2 //number of lines including spaces
let mainRadius = (size - lineWidth) / 2
let startAngle = asin(size * RCConstants.dotSizeScale / mainRadius)
let distancePerBit = (CGFloat.pi / 2 - startAngle * 2) / CGFloat(RCConstants.level1BitesCount)
var points = [CGPoint]()
[RCConstants.level1BitesCount, RCConstants.level2BitesCount, RCConstants.level3BitesCount].enumerated().forEach { row in
let radius = mainRadius - lineWidth * CGFloat(row.offset * 2)
(0..<4).forEach { group in
let baseDistance = -CGFloat.pi / 2 + CGFloat.pi / 2 * CGFloat(group) + startAngle
(0..<row.element).forEach { bitCount in
let angle = baseDistance + distancePerBit * CGFloat(bitCount) + distancePerBit / 2
let x = cos(angle) * radius
let y = sin(angle) * radius
let point = CGPoint(x: x + size / 2, y: y + size / 2)
points.append(point)
}
}
}
pixelData.deallocate()
return points.map { data[Int($0.x), Int($0.y)] > 200 ? RCBit.zero : RCBit.one }
}
}
extension RCImageDecoder {
struct RCPixelPattern: CustomStringConvertible {
let bit: RCBit
let row: Int
let column: Int
var count: Float
var description: String {
"\(bit.debugDescription), start: \(row) \(column), count: \(count)"
}
}
enum Side: CaseIterable {
case left
case top
case right
case bottom
}
}