NSData+ImageContentType.m
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//
// NSData+ImageContentType.m
// WSWebImageDemo
//
// Created by 王帅 on 16/7/21.
// Copyright © 2016年 王帅. All rights reserved.
//
#import "NSData+ImageContentType.h"
@implementation NSData (ImageContentType)
+ (NSString *)ws_imageContentTypeWithData:(NSData *)data
{
uint8_t c;
[data getBytes:&c length:1];
switch (c) {
case 0xFF:
return @"image/jpeg";
case 0x89:
return @"image/png";
case 0x47:
return @"image/gif";
case 0x49:
case 0x4D:
return @"image/tiff";
case 0x52:
if ([data length] < 12) {
return nil;
}
NSString *testString = [[NSString alloc] initWithData:[data subdataWithRange:NSMakeRange(0, 12)] encoding:NSASCIIStringEncoding];
if ([testString hasPrefix:@"RIFF"] && [testString hasSuffix:@"WEBP"]) {
return @"image/webp";
}
return nil;
}
return nil;
}
@end