Merge branch 'master' into pr/145

Author: 叶晓冬

README.md

@@ -51,7 +51,7 @@ Simply add the following lines to your `Podfile`:
 # required by Cocoapods 0.36.0.rc.1 for Swift Pods
 use_frameworks!
 
-pod 'RSBarcodes_Swift', '~> 5.1.0'
+pod 'RSBarcodes_Swift', '~> 5.1.1'
 ```
 
 You will need to import RSBarcodes_Swift manually in the ViewController file after creating the file using wizard.
@@ -63,7 +63,7 @@ You will need to import RSBarcodes_Swift manually in the ViewController file aft
 Simply add the following line to your `Cartfile`:
 
 ```ruby
-github "yeahdongcn/RSBarcodes_Swift" >= 5.1.0
+github "yeahdongcn/RSBarcodes_Swift" >= 5.1.1
 ```
 
 You will need to import RSBarcodes_Swift manually in the ViewController file after creating the file using wizard.

RSBarcodes_Swift.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name         = "RSBarcodes_Swift"
-  s.version      = "5.1.0"
+  s.version      = "5.1.1"
   s.summary      = "1D and 2D barcodes reader and generators for iOS 9 with delightful controls. Now Swift. "
   s.homepage     = "https://github.com/yeahdongcn/RSBarcodes_Swift"
   s.license      = { :type => 'MIT', :file => 'LICENSE.md' }

Source/RSCodeGenerator.swift

@@ -12,6 +12,7 @@ import AVFoundation
 import CoreImage
 
 let DIGITS_STRING = "0123456789"
+let BARCODE_DEFAULT_HEIGHT = 28
 
 // Controls the amount of additional data encoded in the output image to provide error correction.
 // Higher levels of error correction result in larger output images but allow larger areas of the code to be damaged or obscured without.
@@ -106,9 +107,13 @@ open class RSAbstractCodeGenerator : RSCodeGenerator {
         // Top spacing          = 1.5
         // Bottom spacing       = 2
         // Left & right spacing = 2
-        // Height               = 28
         let width = length + 4
-        let size = CGSize(width: CGFloat(width), height: 28)
+        // Calculate the correct aspect ratio, so that the resulting image can be resized to the target size
+        var height = BARCODE_DEFAULT_HEIGHT
+        if let targetSize = targetSize {
+            height = Int(targetSize.height / targetSize.width * CGFloat(width))
+        }
+        let size = CGSize(width: CGFloat(width), height: CGFloat(height))
         UIGraphicsBeginImageContextWithOptions(size, false, 1)
         if let context = UIGraphicsGetCurrentContext() {
             context.setShouldAntialias(false)