如何将文本转换为表情符号？
How to convert Text into Emoji?
我有一个将文本转换为表情符号的计划。但是，我不知道如何开始。这是我正在寻找的一些屏幕截图。
我的想法是，要实现上述结果，我们应该为每个字符保存字典，但问题是该字典将如何根据字符结构保存表情符号。
我建议您使用简单的位图技术。在第一步中，您构建一个黑白位图，其中包含与最终图像相同尺寸的书面文本。
在第二步中，您 "divide" 将此图像转换为光栅，例如比最终表情符号字符小 20% 以创建重叠效果。
在每个光栅矩形中计算黑色像素。在那里你得到一个介于 0-100% 黑色像素之间的百分比。例如，如果此百分比超过 40%，则会在该矩形的中心放置一个随机表情符号。
您可以通过添加少量随机位移来改善效果。
最后的想法
我实现了这个并且效果很好。我可以通过一些小的优化进一步改善图像：
- 对于每个大于 40% 黑色的矩形，我将这个矩形分成四个区域（左上、右上、左下、右下）。
- 如果其中一个区域中有一个黑色像素，我将该区域记为 1，否则记为 0。
- 这将创建 16 种不同的模式。对于这些模式中的一些，我将表情符号从矩形的中心移开更多。
例如，如果我得到 1000，我将它移到左上角。如果我得到 1010 到左边。
示例代码
以下示例代码演示了所示方法，没有 "final thought" 部分中的调整。它是用 Swift 编写的，用于 Cocoa 应用程序。您会看到一个简单应用程序的应用程序委托，它在主 window.
中提供了一个文本字段和一个图像视图
您可以完成将文本字段和图像视图添加到主 window 并将值绑定到插座 textField 和 imageView 的应用程序。您还必须将文本字段值绑定到 parameterText 属性.
应用程序的输出如下所示：
@NSApplicationMain
class AppDelegate: NSObject, NSApplicationDelegate {
@IBOutlet weak var window: NSWindow!
@IBOutlet weak var textField: NSTextField!
@IBOutlet weak var imageView: NSImageView!
var updateTimer: NSTimer = NSTimer()
let canvasSize = CGSize(width: 1024, height: 768)
let canvasPadding: CGFloat = 32.0
let emojiSize = 20.0
let emojiSet: [NSString] = ["","","",""]
let emojiJitter = 4.0
var parameterText: NSString = "Hello!" {
didSet {
triggerImageUpdate()
}
}
func applicationDidFinishLaunching(aNotification: NSNotification) {
triggerImageUpdate()
}
func applicationWillTerminate(aNotification: NSNotification) {
}
func triggerImageUpdate() {
updateTimer.invalidate()
updateTimer = NSTimer.scheduledTimerWithTimeInterval(0.5, target: self, selector: Selector("updateImage"), userInfo: nil, repeats: false);
}
func updateImage() {
imageView.image = createEmojiImage(parameterText, size: canvasSize, padding: canvasPadding)
}
// This function creates a simple bitmap with the given text. The text
// is centered in the bitmap and scaled to the maximum size.
func createTextImage(text: NSString, size: CGSize, padding: CGFloat) -> NSImage {
let canvasRect = CGRect(x: 0.0, y: 0.0, width: size.width, height: size.height)
let textRect = CGRectInset(canvasRect, padding, padding)
var textBitmap = NSImage(size: size)
textBitmap.lockFocus()
NSColor.whiteColor().setFill()
NSRectFill(canvasRect)
let textFont = NSFont(name: "Helvetica Bold", size: 100)
var textAttributes: [NSObject: AnyObject] = [
NSFontAttributeName: textFont!,
NSForegroundColorAttributeName: NSColor.blackColor()]
let textSize = text.sizeWithAttributes(textAttributes);
let scaleWidth = textRect.size.width/textSize.width
let scaleHeight = textRect.size.height/textSize.height
let scale: CGFloat
if (scaleWidth < scaleHeight) {
scale = scaleWidth
} else {
scale = scaleHeight
}
let scaledCanvasSize = CGSize(width: size.width/scale, height: size.height/scale)
let offset = CGPoint(x: (scaledCanvasSize.width - textSize.width)/2.0,
y: (scaledCanvasSize.height - textSize.height)/2.0)
CGContextScaleCTM(NSGraphicsContext.currentContext()!.CGContext, scale, scale)
text.drawAtPoint(offset, withAttributes: textAttributes)
textBitmap.unlockFocus()
return textBitmap
}
func createTextBitmap(text: NSString, size: CGSize, padding: CGFloat) -> NSBitmapImageRep {
let textImage = createTextImage(text, size: size, padding: padding)
let tiffImageData = textImage.TIFFRepresentation
return NSBitmapImageRep(data: tiffImageData!)!
}
// This is a class which represents a single field.
class Field {
let center: CGPoint
let black: Double
init(center: CGPoint, black: Double) {
self.center = center
self.black = black
}
}
// A function to get the black value from a certain rectangle in an image.
func blackValue(image: NSBitmapImageRep, rect: CGRect) -> Double {
let pixelInRect = Int(rect.size.width * rect.size.height)
var blackCount = 0;
for (var x = 0; x < Int(rect.size.width); ++x) {
for (var y = 0; y < Int(rect.size.height); ++y) {
var color = image.colorAtX(Int(rect.origin.x), y: Int(rect.origin.y))!
if (color.redComponent < 0.1) {
blackCount++
}
}
}
return Double(blackCount) / Double(pixelInRect)
}
// A function to rasterize the bitmap into single fields.
func rasterizeBitmap(image: NSBitmapImageRep, size: CGFloat) -> (width: Int, fields: [Field]) {
let width = Int(image.size.width/size)
let height = Int(image.size.height/size)
var fields = [Field]()
for (var x = 0; x < width; ++x) {
for (var y = 0; y < height; ++y) {
let rect = CGRect(x: CGFloat(x) * size, y: CGFloat(y) * size, width: size, height: size)
let center = CGPoint(x: floor(CGFloat(x) * size + size/2.0), y: image.size.height - floor(CGFloat(y) * size + size/2.0))
let black = blackValue(image, rect: rect)
var field = Field(center: center, black: black)
fields.append(field)
}
}
return (width, fields)
}
// Function to create the emoji image.
func createEmojiImage(text: NSString, size: CGSize, padding: CGFloat) -> NSImage {
// Create and rasterize the bitmap.
let textBitmap = self.createTextBitmap(text, size: size, padding: padding)
let (fieldsWidth, fields) = self.rasterizeBitmap(textBitmap, size: CGFloat(emojiSize*0.75))
// Create a new image
var result = NSImage(size: size)
result.lockFocus()
NSColor.whiteColor().setFill()
let canvasRect = CGRect(x: 0.0, y: 0.0, width: size.width, height: size.height)
NSRectFill(canvasRect)
let textFont = NSFont(name: "Apple Color Emoji", size: CGFloat(self.emojiSize))
var textAttributes: [NSObject: AnyObject] = [NSFontAttributeName: textFont!]
NSColor.blackColor().setFill()
for field in fields {
let jitterX = CGFloat(Double(arc4random_uniform(101))/100.0*self.emojiJitter-self.emojiJitter/2.0)
let jitterY = CGFloat(Double(arc4random_uniform(101))/100.0*self.emojiJitter-self.emojiJitter/2.0)
if field.black > 0.4 {
var randomEmoji = self.emojiSet[Int(arc4random_uniform(UInt32(self.emojiSet.count)))]
var drawingPoint = CGPoint(x: field.center.x - CGFloat(self.emojiSize/2.0) + jitterX, y: field.center.y - CGFloat(self.emojiSize/2.0) + jitterY)
randomEmoji.drawAtPoint(drawingPoint, withAttributes: textAttributes)
}
}
result.unlockFocus()
return result
}
}
我有一个将文本转换为表情符号的计划。但是，我不知道如何开始。这是我正在寻找的一些屏幕截图。
我的想法是，要实现上述结果，我们应该为每个字符保存字典，但问题是该字典将如何根据字符结构保存表情符号。
我建议您使用简单的位图技术。在第一步中，您构建一个黑白位图，其中包含与最终图像相同尺寸的书面文本。
在第二步中，您 "divide" 将此图像转换为光栅，例如比最终表情符号字符小 20% 以创建重叠效果。
在每个光栅矩形中计算黑色像素。在那里你得到一个介于 0-100% 黑色像素之间的百分比。例如，如果此百分比超过 40%，则会在该矩形的中心放置一个随机表情符号。
您可以通过添加少量随机位移来改善效果。
最后的想法
我实现了这个并且效果很好。我可以通过一些小的优化进一步改善图像：
- 对于每个大于 40% 黑色的矩形，我将这个矩形分成四个区域（左上、右上、左下、右下）。
- 如果其中一个区域中有一个黑色像素，我将该区域记为 1，否则记为 0。
- 这将创建 16 种不同的模式。对于这些模式中的一些，我将表情符号从矩形的中心移开更多。
例如，如果我得到 1000，我将它移到左上角。如果我得到 1010 到左边。
示例代码
以下示例代码演示了所示方法，没有 "final thought" 部分中的调整。它是用 Swift 编写的，用于 Cocoa 应用程序。您会看到一个简单应用程序的应用程序委托，它在主 window.
中提供了一个文本字段和一个图像视图您可以完成将文本字段和图像视图添加到主 window 并将值绑定到插座 textField 和 imageView 的应用程序。您还必须将文本字段值绑定到 parameterText 属性.
应用程序的输出如下所示：
@NSApplicationMain
class AppDelegate: NSObject, NSApplicationDelegate {
@IBOutlet weak var window: NSWindow!
@IBOutlet weak var textField: NSTextField!
@IBOutlet weak var imageView: NSImageView!
var updateTimer: NSTimer = NSTimer()
let canvasSize = CGSize(width: 1024, height: 768)
let canvasPadding: CGFloat = 32.0
let emojiSize = 20.0
let emojiSet: [NSString] = ["","","",""]
let emojiJitter = 4.0
var parameterText: NSString = "Hello!" {
didSet {
triggerImageUpdate()
}
}
func applicationDidFinishLaunching(aNotification: NSNotification) {
triggerImageUpdate()
}
func applicationWillTerminate(aNotification: NSNotification) {
}
func triggerImageUpdate() {
updateTimer.invalidate()
updateTimer = NSTimer.scheduledTimerWithTimeInterval(0.5, target: self, selector: Selector("updateImage"), userInfo: nil, repeats: false);
}
func updateImage() {
imageView.image = createEmojiImage(parameterText, size: canvasSize, padding: canvasPadding)
}
// This function creates a simple bitmap with the given text. The text
// is centered in the bitmap and scaled to the maximum size.
func createTextImage(text: NSString, size: CGSize, padding: CGFloat) -> NSImage {
let canvasRect = CGRect(x: 0.0, y: 0.0, width: size.width, height: size.height)
let textRect = CGRectInset(canvasRect, padding, padding)
var textBitmap = NSImage(size: size)
textBitmap.lockFocus()
NSColor.whiteColor().setFill()
NSRectFill(canvasRect)
let textFont = NSFont(name: "Helvetica Bold", size: 100)
var textAttributes: [NSObject: AnyObject] = [
NSFontAttributeName: textFont!,
NSForegroundColorAttributeName: NSColor.blackColor()]
let textSize = text.sizeWithAttributes(textAttributes);
let scaleWidth = textRect.size.width/textSize.width
let scaleHeight = textRect.size.height/textSize.height
let scale: CGFloat
if (scaleWidth < scaleHeight) {
scale = scaleWidth
} else {
scale = scaleHeight
}
let scaledCanvasSize = CGSize(width: size.width/scale, height: size.height/scale)
let offset = CGPoint(x: (scaledCanvasSize.width - textSize.width)/2.0,
y: (scaledCanvasSize.height - textSize.height)/2.0)
CGContextScaleCTM(NSGraphicsContext.currentContext()!.CGContext, scale, scale)
text.drawAtPoint(offset, withAttributes: textAttributes)
textBitmap.unlockFocus()
return textBitmap
}
func createTextBitmap(text: NSString, size: CGSize, padding: CGFloat) -> NSBitmapImageRep {
let textImage = createTextImage(text, size: size, padding: padding)
let tiffImageData = textImage.TIFFRepresentation
return NSBitmapImageRep(data: tiffImageData!)!
}
// This is a class which represents a single field.
class Field {
let center: CGPoint
let black: Double
init(center: CGPoint, black: Double) {
self.center = center
self.black = black
}
}
// A function to get the black value from a certain rectangle in an image.
func blackValue(image: NSBitmapImageRep, rect: CGRect) -> Double {
let pixelInRect = Int(rect.size.width * rect.size.height)
var blackCount = 0;
for (var x = 0; x < Int(rect.size.width); ++x) {
for (var y = 0; y < Int(rect.size.height); ++y) {
var color = image.colorAtX(Int(rect.origin.x), y: Int(rect.origin.y))!
if (color.redComponent < 0.1) {
blackCount++
}
}
}
return Double(blackCount) / Double(pixelInRect)
}
// A function to rasterize the bitmap into single fields.
func rasterizeBitmap(image: NSBitmapImageRep, size: CGFloat) -> (width: Int, fields: [Field]) {
let width = Int(image.size.width/size)
let height = Int(image.size.height/size)
var fields = [Field]()
for (var x = 0; x < width; ++x) {
for (var y = 0; y < height; ++y) {
let rect = CGRect(x: CGFloat(x) * size, y: CGFloat(y) * size, width: size, height: size)
let center = CGPoint(x: floor(CGFloat(x) * size + size/2.0), y: image.size.height - floor(CGFloat(y) * size + size/2.0))
let black = blackValue(image, rect: rect)
var field = Field(center: center, black: black)
fields.append(field)
}
}
return (width, fields)
}
// Function to create the emoji image.
func createEmojiImage(text: NSString, size: CGSize, padding: CGFloat) -> NSImage {
// Create and rasterize the bitmap.
let textBitmap = self.createTextBitmap(text, size: size, padding: padding)
let (fieldsWidth, fields) = self.rasterizeBitmap(textBitmap, size: CGFloat(emojiSize*0.75))
// Create a new image
var result = NSImage(size: size)
result.lockFocus()
NSColor.whiteColor().setFill()
let canvasRect = CGRect(x: 0.0, y: 0.0, width: size.width, height: size.height)
NSRectFill(canvasRect)
let textFont = NSFont(name: "Apple Color Emoji", size: CGFloat(self.emojiSize))
var textAttributes: [NSObject: AnyObject] = [NSFontAttributeName: textFont!]
NSColor.blackColor().setFill()
for field in fields {
let jitterX = CGFloat(Double(arc4random_uniform(101))/100.0*self.emojiJitter-self.emojiJitter/2.0)
let jitterY = CGFloat(Double(arc4random_uniform(101))/100.0*self.emojiJitter-self.emojiJitter/2.0)
if field.black > 0.4 {
var randomEmoji = self.emojiSet[Int(arc4random_uniform(UInt32(self.emojiSet.count)))]
var drawingPoint = CGPoint(x: field.center.x - CGFloat(self.emojiSize/2.0) + jitterX, y: field.center.y - CGFloat(self.emojiSize/2.0) + jitterY)
randomEmoji.drawAtPoint(drawingPoint, withAttributes: textAttributes)
}
}
result.unlockFocus()
return result
}
}