使用Base64编码图像的空值

Question

我想将图像加密成Base64字符串。请找到所需的代码。我得到空值作为响应

fullpath = /Users/srt/Library/Application Support/iPhone Simulator/5.1/Applications//Documents/image.png 



UIImage *sImage=[UIImage imageNamed:fullPath]; 
    [fileManager createFileAtPath:fullPath contents:imageData attributes:nil]; 
    NSLog(@"image saved"); 
    NSLog(@"%@",fullPath); 
    NSData* data = UIImageJPEGRepresentation(sImage, 1.0f); 


    NSString *strEncoded = [self Base64ImageEncode:data]; 
    NSLog(@"This is the encryption %@ ",strEncoded); 

-(NSString *)Base64ImageEncode:(NSData *)data{ 
    //Point to start of the data and set buffer sizes 
    int inLength = [data length]; 
    int outLength = ((((inLength * 4)/3)/4)*4) + (((inLength * 4)/3)%4 ? 4 : 0); 
    const char *inputBuffer = [data bytes]; 
    char *outputBuffer = malloc(outLength); 
    outputBuffer[outLength] = 0; 

    //64 digit code 
    static char Encode[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz/"; 

    //start the count 
    int cycle = 0; 
    int inpos = 0; 
    int outpos = 0; 
    char temp; 

    //Pad the last to bytes, the outbuffer must always be a multiple of 4 
    outputBuffer[outLength-1] = '='; 
    outputBuffer[outLength-2] = '='; 

    /* http://en.wikipedia.org/wiki/Base64 
    Text content M   a   n 
    ASCII   77   97   110 
    8 Bit pattern 01001101 01100001 01101110 

    6 Bit pattern 010011 010110 000101 101110 
    Index   19  22  5  46 
    Base64-encoded T  W  F  u 
    */ 


    while (inpos < inLength){ 
     switch (cycle) { 
      case 0: 
       outputBuffer[outpos++] = Encode[(inputBuffer[inpos]&0xFC)>>2]; 
       cycle = 1; 
       break; 
      case 1: 
       temp = (inputBuffer[inpos++]&0x03)<<4; 
       outputBuffer[outpos] = Encode[temp]; 
       cycle = 2; 
       break; 
      case 2: 
       outputBuffer[outpos++] = Encode[temp|(inputBuffer[inpos]&0xF0)>> 4]; 
       temp = (inputBuffer[inpos++]&0x0F)<<2; 
       outputBuffer[outpos] = Encode[temp]; 
       cycle = 3; 
       break; 
      case 3: 
       outputBuffer[outpos++] = Encode[temp|(inputBuffer[inpos]&0xC0)>>6]; 
       cycle = 4; 
       break; 
      case 4: 
       outputBuffer[outpos++] = Encode[inputBuffer[inpos++]&0x3f]; 
       cycle = 0; 
       break; 
      default: 
       cycle = 0; 
       break; 
     } 
    } 
    NSString *pictemp = [NSString stringWithUTF8String:outputBuffer]; 
    free(outputBuffer); 
    return pictemp; 
} 

编码的结果是This is the encryption请纠正我，我的错误和原因还，如果需要或任何其他更好的办法做到这一点。

Answer 1

使用imageNamed:方法无法从文档目录加载图像。 此方法用于从应用程序包中加载图像。参数应该是图像的名称。

像：

UIImage *tempImage = [UIImage imageNamed:@"myImage.png"]; 

这就是为什么像越来越空。

使用imageWithContentsOfFile:方法。

UIImage *sImage = [UIImage imageWithContentsOfFile:fullPath];