NSData+ImageContentType.m
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//
// Created by Fabrice Aneche on 06/01/14.
// Copyright (c) 2014 Dailymotion. All rights reserved.
//
#import "NSData+ImageContentType.h"
@implementation NSData (ImageContentType)
+ (NSString *)contentTypeForImageData:(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:
// R as RIFF for WEBP
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