获取网络图片的大小 改变 图片色值 灰度什么的方法集合－b

直接上代码了 头文件

1. // 图片处理 0 半灰色  1 灰度   2 深棕色    3 反色
2. +(UIImage*)imageWithImage:(UIImage*)image grayLevelType:(UIImageGrayLevelType)type;
3. //色值 变暗多少 0.0 - 1.0
4. +(UIImage*)imageWithImage:(UIImage*)image darkValue:(float)darkValue;
5. /**
6. 获取网络图片的Size, 先通过文件头来获取图片大小
7. 如果失败 会下载完整的图片Data 来计算大小 所以最好别放在主线程
8. 如果你有使用SDWebImage就会先看下 SDWebImage有缓存过改图片没有
9. 支持文件头大小的格式 png、gif、jpg   http://www.cocoachina.com/bbs/read.php?tid=165823
10. */
11. +(CGSize)downloadImageSizeWithURL:(id)imageURL;

代码实现:

1. //讨厌警告
2. -(id)diskImageDataBySearchingAllPathsForKey:(id)key{return nil;}
3. +(CGSize)downloadImageSizeWithURL:(id)imageURL
4. {
5. NSURL* URL = nil;
6. if([imageURL isKindOfClass:[NSURL class]]){
7. URL = imageURL;
8. }
9. if([imageURL isKindOfClass:[NSString class]]){
10. URL = [NSURL URLWithString:imageURL];
11. }
12. if(URL == nil)
13. return CGSizeZero;
14. NSString* absoluteString = URL.absoluteString;
15. #ifdef dispatch_main_sync_safe
16. if([[SDImageCache sharedImageCache] diskImageExistsWithKey:absoluteString])
17. {
18. UIImage* image = [[SDImageCache sharedImageCache] imageFromMemoryCacheForKey:absoluteString];
19. if(!image)
20. {
21. NSData* data = [[SDImageCache sharedImageCache] performSelector:@selector(diskImageDataBySearchingAllPathsForKey:) withObject:URL.absoluteString];
22. image = [UIImage imageWithData:data];
23. }
24. if(image)
25. {
26. return image.size;
27. }
28. }
29. #endif
30. NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:URL];
31. NSString* pathExtendsion = [URL.pathExtension lowercaseString];
32. CGSize size = CGSizeZero;
33. if([pathExtendsion isEqualToString:@"png"]){
34. size =  [self downloadPNGImageSizeWithRequest:request];
35. }
36. else if([pathExtendsion isEqual:@"gif"])
37. {
38. size =  [self downloadGIFImageSizeWithRequest:request];
39. }
40. else{
41. size = [self downloadJPGImageSizeWithRequest:request];
42. }
43. if(CGSizeEqualToSize(CGSizeZero, size))
44. {
45. NSData* data = [NSURLConnection sendSynchronousRequest:[NSURLRequest requestWithURL:URL] returningResponse:nil error:nil];
46. UIImage* image = [UIImage imageWithData:data];
47. if(image)
48. {
49. #ifdef dispatch_main_sync_safe
50. [[SDImageCache sharedImageCache] storeImage:image recalculateFromImage:YES imageData:data forKey:URL.absoluteString toDisk:YES];
51. #endif
52. size = image.size;
53. }
54. }
55. return size;
56. }
57. +(CGSize)downloadPNGImageSizeWithRequest:(NSMutableURLRequest*)request
58. {
59. [request setValue:@"bytes=16-23" forHTTPHeaderField:@"Range"];
60. NSData* data = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
61. if(data.length == 8)
62. {
63. int w1 = 0, w2 = 0, w3 = 0, w4 = 0;
64. [data getBytes:&w1 range:NSMakeRange(0, 1)];
65. [data getBytes:&w2 range:NSMakeRange(1, 1)];
66. [data getBytes:&w3 range:NSMakeRange(2, 1)];
67. [data getBytes:&w4 range:NSMakeRange(3, 1)];
68. int w = (w1 << 24) + (w2 << 16) + (w3 << 8) + w4;
69. int h1 = 0, h2 = 0, h3 = 0, h4 = 0;
70. [data getBytes:&h1 range:NSMakeRange(4, 1)];
71. [data getBytes:&h2 range:NSMakeRange(5, 1)];
72. [data getBytes:&h3 range:NSMakeRange(6, 1)];
73. [data getBytes:&h4 range:NSMakeRange(7, 1)];
74. int h = (h1 << 24) + (h2 << 16) + (h3 << 8) + h4;
75. return CGSizeMake(w, h);
76. }
77. return CGSizeZero;
78. }
79. +(CGSize)downloadGIFImageSizeWithRequest:(NSMutableURLRequest*)request
80. {
81. [request setValue:@"bytes=6-9" forHTTPHeaderField:@"Range"];
82. NSData* data = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
83. if(data.length == 4)
84. {
85. short w1 = 0, w2 = 0;
86. [data getBytes:&w1 range:NSMakeRange(0, 1)];
87. [data getBytes:&w2 range:NSMakeRange(1, 1)];
88. short w = w1 + (w2 << 8);
89. short h1 = 0, h2 = 0;
90. [data getBytes:&h1 range:NSMakeRange(2, 1)];
91. [data getBytes:&h2 range:NSMakeRange(3, 1)];
92. short h = h1 + (h2 << 8);
93. return CGSizeMake(w, h);
94. }
95. return CGSizeZero;
96. }
97. +(CGSize)downloadJPGImageSizeWithRequest:(NSMutableURLRequest*)request
98. {
99. [request setValue:@"bytes=0-209" forHTTPHeaderField:@"Range"];
100. NSData* data = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
101. if ([data length] <= 0x58) {
102. return CGSizeZero;
103. }
104. if ([data length] < 210) {// 肯定只有一个DQT字段
105. short w1 = 0, w2 = 0;
106. [data getBytes:&w1 range:NSMakeRange(0x60, 0x1)];
107. [data getBytes:&w2 range:NSMakeRange(0x61, 0x1)];
108. short w = (w1 << 8) + w2;
109. short h1 = 0, h2 = 0;
110. [data getBytes:&h1 range:NSMakeRange(0x5e, 0x1)];
111. [data getBytes:&h2 range:NSMakeRange(0x5f, 0x1)];
112. short h = (h1 << 8) + h2;
113. return CGSizeMake(w, h);
114. } else {
115. short word = 0x0;
116. [data getBytes:&word range:NSMakeRange(0x15, 0x1)];
117. if (word == 0xdb) {
118. [data getBytes:&word range:NSMakeRange(0x5a, 0x1)];
119. if (word == 0xdb) {// 两个DQT字段
120. short w1 = 0, w2 = 0;
121. [data getBytes:&w1 range:NSMakeRange(0xa5, 0x1)];
122. [data getBytes:&w2 range:NSMakeRange(0xa6, 0x1)];
123. short w = (w1 << 8) + w2;
124. short h1 = 0, h2 = 0;
125. [data getBytes:&h1 range:NSMakeRange(0xa3, 0x1)];
126. [data getBytes:&h2 range:NSMakeRange(0xa4, 0x1)];
127. short h = (h1 << 8) + h2;
128. return CGSizeMake(w, h);
129. } else {// 一个DQT字段
130. short w1 = 0, w2 = 0;
131. [data getBytes:&w1 range:NSMakeRange(0x60, 0x1)];
132. [data getBytes:&w2 range:NSMakeRange(0x61, 0x1)];
133. short w = (w1 << 8) + w2;
134. short h1 = 0, h2 = 0;
135. [data getBytes:&h1 range:NSMakeRange(0x5e, 0x1)];
136. [data getBytes:&h2 range:NSMakeRange(0x5f, 0x1)];
137. short h = (h1 << 8) + h2;
138. return CGSizeMake(w, h);
139. }
140. } else {
141. return CGSizeZero;
142. }
143. }
144. }

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