In my app, i use UIImageView and UIScrollView to show lot of pictures(Every time there are about 20 pictures and every pictures about 600px*500px and size is about 600KB ), i use for this code to do this function. Here is code:

//Here is pictures Data;
self.klpArry = self.pictureData;

CGSize size = self.klpScrollView1.frame.size;
for (int i=0; i < [klpArr count]; i++) {
    UIImageView *iv = [[UIImageView alloc] initWithFrame:CGRectMake((size.width * i)+300, 20, 546, 546)];
    NSString *filePath = [[NSBundle mainBundle] pathForResource:[klpArr objectAtIndex:i] ofType:@"jpg"];
    UIImage *imageData = [[UIImage alloc]initWithData:[NSData dataWithContentsOfFile:filePath]];
    [iv setImage:imageData];   
    iv.backgroundColor = [UIColor grayColor];
    [self.klpScrollView1 addSubview:iv];
    imageData = nil;
    iv = nil;
    iv.image = nil;
    filePath = nil;
    [imageData release];
    [filePath release];
    [iv release];
}
    // show the picture in scrollview;
[self.klpScrollView1 setContentSize:CGSizeMake(size.width * numImage, size.height)];
self.klpScrollView1.pagingEnabled = YES;
self.klpScrollView1.showsHorizontalScrollIndicator = NO;
self.klpScrollView1.backgroundColor = [UIColor grayColor];

But everytime i init this function, the memory will increase about 5MB, Actually i release UIImageView, UIimage and UIScrollView (vi.image=nil,[vi release]) but i doesn't work, it can't release the memory. BTW, i use my friend code first vi.image=nil then vi=nil; but the pictures not to show on scrollview. any one can help me ?? Thx ~~