压缩图像文件大小 (iPhone)？

Question

我有一个简单的 iPhone 应用程序，允许用户将图像上传到服务器。问题是，如果他们上传一个大图像文件怎么办。我想将其限制为（最大）200 KB。我开始了一些事情，但它似乎在我的while 声明中崩溃了。

代码如下：

NSString *jpgPath = [NSString stringWithFormat:@"Documents/%@",sqlImageUploadPathTwo];
NSString *jpgPathTwo = [NSString stringWithFormat:@"./../Documents/%@",sqlImageUploadPathTwo];
NSString *yourPath = [NSHomeDirectory() stringByAppendingPathComponent:jpgPath];

NSLog(@"yourPath: %@", yourPath);

NSFileManager *man = [[NSFileManager alloc] init];
NSDictionary *attrs = [man attributesOfItemAtPath: yourPath error: NULL];
int *result = [attrs fileSize];
NSLog(@"Here's the original size: %d", result);

NSLog(@"jpgPath: %@ // jpgPathTwo: %@", jpgPath, jpgPathTwo);

while (result > 9715) {
    UIImage *tempImage = [UIImage imageNamed: jpgPath];
    NSData *imageData = [NSData dataWithData:UIImageJPEGRepresentation(tempImage, 0.9)];
    [imageData writeToFile:jpgPathTwo atomically:YES];
    NSLog(@"just shrunk it once.");
}

NSLog(@"SIZE AFTER SHRINK: %@", result);

谢谢！
库尔顿

Answer 1

类似这样的： （另请注意，您将结果声明为 int*（即指针），而不是数字，并且条件应该是 >，而不是

NSFileManager *man = [[NSFileManager alloc] init];
NSDictionary *attrs = [man attributesOfItemAtPath: yourPath error: NULL];
int result = [attrs fileSize];
int count = 0;
while (result > 9715 && count < 5) {
    UIImage *tempImage = [UIImage imageNamed: jpgPath];
    NSData *imageData = [NSData dataWithData:UIImageJPEGRepresentation(tempImage, 0.9)];
    [imageData writeToFile:jpgPathTwo atomically:YES];
    NSDictionary *attrs = [man attributesOfItemAtPath: jpgPathTwo error: NULL];
    result = [attrs fileSize];
    count++;
    NSLog(@"just shrunk it once.");
}