感谢Chintan R Dave: - UIImageScanlineFloodfill
我使用以下UIImage类别填充封闭轮廓中的颜色。它使用扫描线泛光填充算法。
对于未从设备捕获的图像,它可以正常工作。对于从设备捕获的图像,它给我EXC_BAD_ACCESS错误(如问题末尾给出的屏幕截图所示)。众所周知,这种类型的错误确实难以实现。所以我真的很感谢有关如何开始解决方案的建议。
代码如下: -
的UIImage + FloodFill.m
@implementation UIImage (FloodFill)
/*
startPoint : Point from where you want to color. Generaly this is touch point.
This is important because color at start point will be replaced with other.
newColor : This color will be apply at point where the match on startPoint color found.
tolerance : If Tolerance is 0 than it will search for exact match of color
other wise it will take range according to tolerance value.
If You dont want to use tolerance and want to incress performance Than you can change
compareColor(ocolor, color, tolerance) with just ocolor==color which reduse function call.
*/
- (UIImage *) floodFillFromPoint:(CGPoint)startPoint withColor:(UIColor *)newColor andTolerance:(int)tolerance
{
return [self floodFillFromPoint:startPoint withColor:newColor andTolerance:tolerance useAntiAlias:YES];
}
- (UIImage *) floodFillFromPoint:(CGPoint)startPoint withColor:(UIColor *)newColor andTolerance:(int)tolerance useAntiAlias:(BOOL)antiAlias
{
@try
{
/*
First We create rowData from UIImage.
We require this conversation so that we can use detail at pixel like color at pixel.
*/
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGImageRef imageRef = [self CGImage];
NSUInteger width = CGImageGetWidth(imageRef);
NSUInteger height = CGImageGetHeight(imageRef);
unsigned char *imageData = malloc(height * width * 4);
NSUInteger bytesPerPixel = CGImageGetBitsPerPixel(imageRef) / 8;
NSUInteger bytesPerRow = CGImageGetBytesPerRow(imageRef);
NSUInteger bitsPerComponent = CGImageGetBitsPerComponent(imageRef);
CGBitmapInfo bitmapInfo = CGImageGetBitmapInfo(imageRef);
if (kCGImageAlphaLast == (uint32_t)bitmapInfo || kCGImageAlphaFirst == (uint32_t)bitmapInfo) {
bitmapInfo = (uint32_t)kCGImageAlphaPremultipliedLast;
}
CGContextRef context = CGBitmapContextCreate(imageData,
width,
height,
bitsPerComponent,
bytesPerRow,
colorSpace,
bitmapInfo);
CGColorSpaceRelease(colorSpace);
CGContextDrawImage(context, CGRectMake(0, 0, width, height), imageRef);
//Get color at start point
unsigned int byteIndex = (bytesPerRow * roundf(startPoint.y)) + roundf(startPoint.x) * bytesPerPixel;
unsigned int ocolor = getColorCode(byteIndex, imageData);
if (compareColor(ocolor, 0, 0)) {
return nil;
}
//Convert newColor to RGBA value so we can save it to image.
int newRed, newGreen, newBlue, newAlpha;
const CGFloat *components = CGColorGetComponents(newColor.CGColor);
if(CGColorGetNumberOfComponents(newColor.CGColor) == 2)
{
newRed = newGreen = newBlue = components[0] * 255;
newAlpha = components[1] * 255;
}
else if (CGColorGetNumberOfComponents(newColor.CGColor) == 4)
{
if ((bitmapInfo&kCGBitmapByteOrderMask) == kCGBitmapByteOrder32Little)
{
newRed = components[2] * 255;
newGreen = components[1] * 255;
newBlue = components[0] * 255;
newAlpha = 255;
}
else
{
newRed = components[0] * 255;
newGreen = components[1] * 255;
newBlue = components[2] * 255;
newAlpha = 255;
}
}
unsigned int ncolor = (newRed << 24) | (newGreen << 16) | (newBlue << 8) | newAlpha;
/*
We are using stack to store point.
Stack is implemented by LinkList.
To incress speed I have used NSMutableData insted of NSMutableArray.
*/
LinkedListStack *points = [[LinkedListStack alloc] initWithCapacity:500 incrementSize:500 andMultiplier:height];
LinkedListStack *antiAliasingPoints = [[LinkedListStack alloc] initWithCapacity:500 incrementSize:500 andMultiplier:height];
int x = roundf(startPoint.x);
int y = roundf(startPoint.y);
[points pushFrontX:x andY:y];
/*
Scanline Floodfill Algorithm With Stack (floodFillScanlineStack)
*/
unsigned int color;
BOOL spanLeft,spanRight;
while ([points popFront:&x andY:&y] != INVALID_NODE_CONTENT)
{
byteIndex = (bytesPerRow * roundf(y)) + roundf(x) * bytesPerPixel;
color = getColorCode(byteIndex, imageData);
while(y >= 0 && compareColor(ocolor, color, tolerance))
{
y--;
if(y >= 0)
{
byteIndex = (bytesPerRow * roundf(y)) + roundf(x) * bytesPerPixel;
color = getColorCode(byteIndex, imageData);
}
}
// Add the top most point on the antialiasing list
if(y >= 0 && !compareColor(ocolor, color, 0))
{
[antiAliasingPoints pushFrontX:x andY:y];
}
y++;
spanLeft = spanRight = NO;
byteIndex = (bytesPerRow * roundf(y)) + roundf(x) * bytesPerPixel;
color = getColorCode(byteIndex, imageData);
while (y < height && compareColor(ocolor, color, tolerance) && ncolor != color)
{
//Change old color with newColor RGBA value
imageData[byteIndex + 0] = newRed;
imageData[byteIndex + 1] = newGreen;
imageData[byteIndex + 2] = newBlue;
imageData[byteIndex + 3] = newAlpha;
if(x > 0)
{
byteIndex = (bytesPerRow * roundf(y)) + roundf(x - 1) * bytesPerPixel;
color = getColorCode(byteIndex, imageData);
if(!spanLeft && x > 0 && compareColor(ocolor, color, tolerance))
{
[points pushFrontX:(x - 1) andY:y];
spanLeft = YES;
}
else if(spanLeft && x > 0 && !compareColor(ocolor, color, tolerance))
{
spanLeft = NO;
}
// we can't go left. Add the point on the antialiasing list
if(!spanLeft && x > 0 && !compareColor(ocolor, color, tolerance) && !compareColor(ncolor, color, tolerance))
{
[antiAliasingPoints pushFrontX:(x - 1) andY:y];
}
}
if(x < width - 1)
{
byteIndex = (bytesPerRow * roundf(y)) + roundf(x + 1) * bytesPerPixel;;
color = getColorCode(byteIndex, imageData);
if(!spanRight && compareColor(ocolor, color, tolerance))
{
[points pushFrontX:(x + 1) andY:y];
spanRight = YES;
}
else if(spanRight && !compareColor(ocolor, color, tolerance))
{
spanRight = NO;
}
// we can't go right. Add the point on the antialiasing list
if(!spanRight && !compareColor(ocolor, color, tolerance) && !compareColor(ncolor, color, tolerance))
{
[antiAliasingPoints pushFrontX:(x + 1) andY:y];
}
}
y++;
if(y < height)
{
byteIndex = (bytesPerRow * roundf(y)) + roundf(x) * bytesPerPixel;
color = getColorCode(byteIndex, imageData);
}
}
if (y<height)
{
byteIndex = (bytesPerRow * roundf(y)) + roundf(x) * bytesPerPixel;
color = getColorCode(byteIndex, imageData);
// Add the bottom point on the antialiasing list
if (!compareColor(ocolor, color, 0))
[antiAliasingPoints pushFrontX:x andY:y];
}
}
// For each point marked
// perform antialiasing on the same pixel, plus the top,left,bottom and right pixel
unsigned int antialiasColor = getColorCodeFromUIColor(newColor,bitmapInfo&kCGBitmapByteOrderMask );
int red1 = ((0xff000000 & antialiasColor) >> 24);
int green1 = ((0x00ff0000 & antialiasColor) >> 16);
int blue1 = ((0x0000ff00 & antialiasColor) >> 8);
int alpha1 = (0x000000ff & antialiasColor);
while ([antiAliasingPoints popFront:&x andY:&y] != INVALID_NODE_CONTENT)
{
byteIndex = (bytesPerRow * roundf(y)) + roundf(x) * bytesPerPixel;
color = getColorCode(byteIndex, imageData);
if (!compareColor(ncolor, color, 0))
{
int red2 = ((0xff000000 & color) >> 24);
int green2 = ((0x00ff0000 & color) >> 16);
int blue2 = ((0x0000ff00 & color) >> 8);
int alpha2 = (0x000000ff & color);
if (antiAlias) {
imageData[byteIndex + 0] = (red1 + red2) / 2;
imageData[byteIndex + 1] = (green1 + green2) / 2;
imageData[byteIndex + 2] = (blue1 + blue2) / 2;
imageData[byteIndex + 3] = (alpha1 + alpha2) / 2;
} else {
imageData[byteIndex + 0] = red2;
imageData[byteIndex + 1] = green2;
imageData[byteIndex + 2] = blue2;
imageData[byteIndex + 3] = alpha2;
}
#if DEBUG_ANTIALIASING
imageData[byteIndex + 0] = 0;
imageData[byteIndex + 1] = 0;
imageData[byteIndex + 2] = 255;
imageData[byteIndex + 3] = 255;
#endif
}
// left
if (x>0)
{
byteIndex = (bytesPerRow * roundf(y)) + roundf(x - 1) * bytesPerPixel;
color = getColorCode(byteIndex, imageData);
if (!compareColor(ncolor, color, 0))
{
int red2 = ((0xff000000 & color) >> 24);
int green2 = ((0x00ff0000 & color) >> 16);
int blue2 = ((0x0000ff00 & color) >> 8);
int alpha2 = (0x000000ff & color);
if (antiAlias) {
imageData[byteIndex + 0] = (red1 + red2) / 2;
imageData[byteIndex + 1] = (green1 + green2) / 2;
imageData[byteIndex + 2] = (blue1 + blue2) / 2;
imageData[byteIndex + 3] = (alpha1 + alpha2) / 2;
} else {
imageData[byteIndex + 0] = red2;
imageData[byteIndex + 1] = green2;
imageData[byteIndex + 2] = blue2;
imageData[byteIndex + 3] = alpha2;
}
#if DEBUG_ANTIALIASING
imageData[byteIndex + 0] = 0;
imageData[byteIndex + 1] = 0;
imageData[byteIndex + 2] = 255;
imageData[byteIndex + 3] = 255;
#endif
}
}
if (x<width)
{
byteIndex = (bytesPerRow * roundf(y)) + roundf(x + 1) * bytesPerPixel;
color = getColorCode(byteIndex, imageData);
if (!compareColor(ncolor, color, 0))
{
int red2 = ((0xff000000 & color) >> 24);
int green2 = ((0x00ff0000 & color) >> 16);
int blue2 = ((0x0000ff00 & color) >> 8);
int alpha2 = (0x000000ff & color);
if (antiAlias) {
imageData[byteIndex + 0] = (red1 + red2) / 2;
imageData[byteIndex + 1] = (green1 + green2) / 2;
imageData[byteIndex + 2] = (blue1 + blue2) / 2;
imageData[byteIndex + 3] = (alpha1 + alpha2) / 2;
} else {
imageData[byteIndex + 0] = red2;
imageData[byteIndex + 1] = green2;
imageData[byteIndex + 2] = blue2;
imageData[byteIndex + 3] = alpha2;
}
#if DEBUG_ANTIALIASING
imageData[byteIndex + 0] = 0;
imageData[byteIndex + 1] = 0;
imageData[byteIndex + 2] = 255;
imageData[byteIndex + 3] = 255;
#endif
}
}
if (y>0)
{
byteIndex = (bytesPerRow * roundf(y - 1)) + roundf(x) * bytesPerPixel;
color = getColorCode(byteIndex, imageData);
if (!compareColor(ncolor, color, 0))
{
int red2 = ((0xff000000 & color) >> 24);
int green2 = ((0x00ff0000 & color) >> 16);
int blue2 = ((0x0000ff00 & color) >> 8);
int alpha2 = (0x000000ff & color);
if (antiAlias) {
imageData[byteIndex + 0] = (red1 + red2) / 2;
imageData[byteIndex + 1] = (green1 + green2) / 2;
imageData[byteIndex + 2] = (blue1 + blue2) / 2;
imageData[byteIndex + 3] = (alpha1 + alpha2) / 2;
} else {
imageData[byteIndex + 0] = red2;
imageData[byteIndex + 1] = green2;
imageData[byteIndex + 2] = blue2;
imageData[byteIndex + 3] = alpha2;
}
#if DEBUG_ANTIALIASING
imageData[byteIndex + 0] = 0;
imageData[byteIndex + 1] = 0;
imageData[byteIndex + 2] = 255;
imageData[byteIndex + 3] = 255;
#endif
}
}
if (y<height)
{
byteIndex = (bytesPerRow * roundf(y + 1)) + roundf(x) * bytesPerPixel;
color = getColorCode(byteIndex, imageData);
if (!compareColor(ncolor, color, 0))
{
int red2 = ((0xff000000 & color) >> 24);
int green2 = ((0x00ff0000 & color) >> 16);
int blue2 = ((0x0000ff00 & color) >> 8);
int alpha2 = (0x000000ff & color);
if (antiAlias) {
imageData[byteIndex + 0] = (red1 + red2) / 2;
imageData[byteIndex + 1] = (green1 + green2) / 2;
imageData[byteIndex + 2] = (blue1 + blue2) / 2;
imageData[byteIndex + 3] = (alpha1 + alpha2) / 2;
} else {
imageData[byteIndex + 0] = red2;
imageData[byteIndex + 1] = green2;
imageData[byteIndex + 2] = blue2;
imageData[byteIndex + 3] = alpha2;
}
#if DEBUG_ANTIALIASING
imageData[byteIndex + 0] = 0;
imageData[byteIndex + 1] = 0;
imageData[byteIndex + 2] = 255;
imageData[byteIndex + 3] = 255;
#endif
}
}
}
//Convert Flood filled image row data back to UIImage object.
CGImageRef newCGImage = CGBitmapContextCreateImage(context);
UIImage *result = [UIImage imageWithCGImage:newCGImage scale:[self scale] orientation:UIImageOrientationUp];
CGImageRelease(newCGImage);
CGContextRelease(context);
free(imageData);
return result;
}
@catch (NSException *exception)
{
NSLog(@"Exception : %@", exception);
}
}
/*
I have used pure C function because it is said than C function is faster than Objective - C method in call.
This two function are called most of time so it require that calling this work in speed.
I have not verified this performance so I like to here comment on this.
*/
/*
This function extract color from image and convert it to integer represent.
Converting to integer make comperation easy.
*/
unsigned int getColorCode (unsigned int byteIndex, unsigned char *imageData)
{
unsigned int red = imageData[byteIndex];
unsigned int green = imageData[byteIndex + 1];
unsigned int blue = imageData[byteIndex + 2];
unsigned int alpha = imageData[byteIndex + 3];
return (red << 24) | (green << 16) | (blue << 8) | alpha;
}
/*
This function compare two color with counting tolerance value.
If color is between tolerance rancge than it return true other wise false.
*/
bool compareColor (unsigned int color1, unsigned int color2, int tolorance)
{
if(color1 == color2)
return true;
int red1 = ((0xff000000 & color1) >> 24);
int green1 = ((0x00ff0000 & color1) >> 16);
int blue1 = ((0x0000ff00 & color1) >> 8);
int alpha1 = (0x000000ff & color1);
int red2 = ((0xff000000 & color2) >> 24);
int green2 = ((0x00ff0000 & color2) >> 16);
int blue2 = ((0x0000ff00 & color2) >> 8);
int alpha2 = (0x000000ff & color2);
int diffRed = abs(red2 - red1);
int diffGreen = abs(green2 - green1);
int diffBlue = abs(blue2 - blue1);
int diffAlpha = abs(alpha2 - alpha1);
if( diffRed > tolorance ||
diffGreen > tolorance ||
diffBlue > tolorance ||
diffAlpha > tolorance )
{
return false;
}
return true;
}
unsigned int getColorCodeFromUIColor(UIColor *color, CGBitmapInfo orderMask)
{
//Convert newColor to RGBA value so we can save it to image.
int newRed, newGreen, newBlue, newAlpha;
const CGFloat *components = CGColorGetComponents(color.CGColor);
if(CGColorGetNumberOfComponents(color.CGColor) == 2)
{
newRed = newGreen = newBlue = components[0] * 255;
newAlpha = components[1] * 255;
}
else if (CGColorGetNumberOfComponents(color.CGColor) == 4)
{
if (orderMask == kCGBitmapByteOrder32Little)
{
newRed = components[2] * 255;
newGreen = components[1] * 255;
newBlue = components[0] * 255;
newAlpha = 255;
}
else
{
newRed = components[0] * 255;
newGreen = components[1] * 255;
newBlue = components[2] * 255;
newAlpha = 255;
}
}
else
{
newRed = newGreen = newBlue = 0;
newAlpha = 255;
}
unsigned int ncolor = (newRed << 24) | (newGreen << 16) | (newBlue << 8) | newAlpha;
return ncolor;
}
@end
LinkedListStack.h
#import <Foundation/Foundation.h>
#define FINAL_NODE_OFFSET -1
#define INVALID_NODE_CONTENT INT_MIN
typedef struct PointNode
{
int nextNodeOffset;
int point;
} PointNode;
@interface LinkedListStack : NSObject
{
NSMutableData *nodeCache;
int freeNodeOffset;
int topNodeOffset;
int _cacheSizeIncrements;
int multiplier;
}
- (id)initWithCapacity:(int)capacity incrementSize:(int)increment andMultiplier:(int)mul;
- (id)initWithCapacity:(int)capacity;
- (void)pushFrontX:(int)x andY:(int)y;
- (int)popFront:(int *)x andY:(int *)y;
@end
LinkedListStack.m
#import "LinkedListStack.h"
@implementation LinkedListStack
#pragma mark - Initialisation
/*
A linked List is create with size of <capicity>.
When you add more element that <capicity> than Lisk List is incressed by size <increment>
mul is value for H (for H see comment Stack methods)
*/
- (id)init
{
return [self initWithCapacity:500];
}
- (id)initWithCapacity:(int)capacity
{
return [self initWithCapacity:capacity incrementSize:500 andMultiplier:1000];
}
- (id)initWithCapacity:(int)capacity incrementSize:(int)increment andMultiplier:(int)mul
{
self = [super init];
if(self)
{
_cacheSizeIncrements = increment;
int bytesRequired = capacity * sizeof(PointNode);
nodeCache = [[NSMutableData alloc] initWithLength:bytesRequired];
[self initialiseNodesAtOffset:0 count:capacity];
freeNodeOffset = 0;
topNodeOffset = FINAL_NODE_OFFSET;
multiplier = mul;
}
return self;
}
#pragma mark - Stack methods
/*
X and Y are converted in single integer value (P) to push in stack.
And again that value (P) are converted to X and Y when pop by using following equation:
P = H * X + Y
X = P / H;
Y = P % H;
H is same for all X and Y and must be grater than Y. So generaly Height is prefered value;
*/
- (void)pushFrontX:(int)x andY:(int)y;
{
int p = multiplier * x + y;
PointNode *node = [self getNextFreeNode];
node->point = p;
node->nextNodeOffset = topNodeOffset;
topNodeOffset = [self offsetOfNode:node];
}
- (int)popFront:(int *)x andY:(int *)y;
{
if(topNodeOffset == FINAL_NODE_OFFSET)
{
return INVALID_NODE_CONTENT;
}
PointNode *node = [self nodeAtOffset:topNodeOffset];
int thisNodeOffset = topNodeOffset;
// Remove this node from the queue
topNodeOffset = node->nextNodeOffset;
int value = node->point;
// Reset it and add it to the free node cache
node->point = 0;
node->nextNodeOffset = freeNodeOffset;
freeNodeOffset = thisNodeOffset;
*x = value / multiplier;
*y = value % multiplier;
return value;
}
#pragma mark - utility functions
- (int)offsetOfNode:(PointNode *)node
{
return node - (PointNode *)nodeCache.mutableBytes;
}
- (PointNode *)nodeAtOffset:(int)offset
{
return (PointNode *)nodeCache.mutableBytes + offset;
}
- (PointNode *)getNextFreeNode
{
if(freeNodeOffset < 0)
{
// Need to extend the size of the nodeCache
int currentSize = nodeCache.length / sizeof(PointNode);
[nodeCache increaseLengthBy:_cacheSizeIncrements * sizeof(PointNode)];
// Set these new nodes to be the free ones
[self initialiseNodesAtOffset:currentSize count:_cacheSizeIncrements];
freeNodeOffset = currentSize;
}
PointNode *node = (PointNode*)nodeCache.mutableBytes + freeNodeOffset;
freeNodeOffset = node->nextNodeOffset;
return node;
}
- (void)initialiseNodesAtOffset:(int)offset count:(int)count
{
PointNode *node = (PointNode *)nodeCache.mutableBytes + offset;
for (int i=0; i<count - 1; i++)
{
node->point = 0;
node->nextNodeOffset = offset + i + 1;
node++;
}
node->point = 0;
// Set the next node offset to make sure we don't continue
node->nextNodeOffset = FINAL_NODE_OFFSET;
}
提出错误的代码: -
unsigned int getColorCode (unsigned int byteIndex, unsigned char *imageData)
{
unsigned int red = imageData[byteIndex];
unsigned int green = imageData[byteIndex + 1];
unsigned int blue = imageData[byteIndex + 2];
unsigned int alpha = imageData[byteIndex + 3];
return (red << 24) | (green << 16) | (blue << 8) | alpha;
}
屏幕拍摄
给我错误的图片:
答案 0 :(得分:2)
我在github repo documentation
的公开问题上解决了这个问题问题出在UIImage + Floodfill.m上,大约是第60行,
CGImageRef imageRef = [self CGImage];
在第40行,班级打电话:
CGDataProviderRef imgDataProvider = CGDataProviderCreateWithCFData((CFDataRef)UIImagePNGRepresentation(self));
CGImageRef imageRef = CGImageCreateWithPNGDataProvider(imgDataProvider, NULL, true, kCGRenderingIntentDefault);
所以我没有用那种方式获得CGImageRef,而是使用了图像的NSData:
var monthNames = ['jan', 'fev', 'mar', 'abr', 'mai', 'jun', 'jul', 'ago', 'set', 'out', 'nov', 'dez'];
var objectYouWant = monthNames.map(function(month) { return {Mes: month}; });
console.log(objectYouWant);
// To convert to json
var jsonYouThinkYouWant = JSON.stringify(objectYouWant);
console.log(jsonYouThinkYouWant );
// Object you think you want.
var objectYouThinkIsDifferent = [{Mes:'jan'}, {Mes:'fev'}, {Mes:'mar'}, {Mes:'abr'}, {Mes:'mai'}, {Mes:'jun'}, {Mes:'jul'}, {Mes:'ago'}, {Mes:'set'}, {Mes:'out'}, {Mes:'nov'}, {Mes:'dez'}];
// Notice that the object is the same as the object my solution provides in the log.
console.log(objectYouThinkIsDifferent);
我把它变成了PNG,因为我正在使用该库来制作alpha泛光填充,而不是纯色填充。只要CGDataRef和CGImageRef是从相同的格式获得的,它就修复了坏的访问崩溃。此外,我没有包含释放这些对象的内存,就像我稍后在代码中所做的那样,但只是想指出它。
有点迟到但希望这会帮助其他人使用该代码。
答案 1 :(得分:0)
当你调用一个解除分配的对象,它的&#34;僵尸&#34; 你可以按照以下步骤搞清楚:
在&#39;编辑方案&#39;中启用僵尸对象
配置文件而不是Xcode中的正常运行(长按运行按钮)
然后使用其中一种乐器(即[zombie])
并记录活动
你可以关注this link,因为我没有多少名声可以发布两个以上的链接!