IOS 圖片上傳處理 圖片壓縮 圖片處理

提到從網路攝影機/相簿擷取圖片是面向終端使用者的，由使用者去瀏覽並選擇圖片為程式使用。在這裡，我們需要過UIImagePickerController類來和使用者互動。
使用UIImagePickerController和使用者互動，我們需要實現2個協議<UIImagePickerControllerDelegate,UINavigationControllerDelegate>。

 

View Code

 

代碼如下 複製代碼

 

#pragma mark 從使用者相簿擷取活動圖表片

- (void)pickImageFromAlbum

{

    imagePicker = [[UIImagePickerController alloc] init];

    imagePicker.delegate =self;

    imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

    imagePicker.modalTransitionStyle = UIModalTransitionStyleCoverVertical;

    imagePicker.allowsEditing =YES;

   
    [self presentModalViewController:imagePicker animated:YES];

}

 

我們來看看上面的從相簿擷取圖片，我們首先要執行個體化UIImagePickerController對象，然後設定imagePicker對象為當前對象，設定imagePicker的圖片來源為UIImagePickerControllerSourceTypePhotoLibrary，表明當前圖片的來源為相簿，除此之外還可以設定使用者對圖片是否可編輯。

View Code

 

代碼如下 複製代碼

#pragma mark 從網路攝影機擷取活動圖表片

- (void)pickImageFromCamera

{

    imagePicker = [[UIImagePickerController alloc] init];

    imagePicker.delegate =self;

    imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;

    imagePicker.modalTransitionStyle = UIModalTransitionStyleCoverVertical;

    imagePicker.allowsEditing =YES;

   
    [self presentModalViewController:imagePicker animated:YES];

}

 

//開啟相機

- (IBAction)touch_photo:(id)sender {

    // for iphone

    UIImagePickerController *pickerImage = [[UIImagePickerController alloc] init];

   if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {

        pickerImage.sourceType = UIImagePickerControllerSourceTypeCamera;

        pickerImage.mediaTypes = [UIImagePickerController availableMediaTypesForSourceType:pickerImage.sourceType];

       
    }

    pickerImage.delegate =self;

    pickerImage.allowsEditing =YES;//自訂照片樣式

    [self presentViewController:pickerImage animated:YES completion:nil];

}

 

以上是從網路攝影機擷取圖片，和從相簿擷取圖片只是圖片來源的設定不一樣，網路攝影機圖片的來源為UIImagePickerControllerSourceTypeCamera。

　　　　在和使用者互動之後，使用者選擇好圖片後，會回調選擇結束的方法。

 

-(void)imagePickerController:(UIImagePickerController*)picker didFinishPickingMediaWithInfo:(NSDictionary*)info

{

    //初始化imageNew為從相機中獲得的--

    UIImage *imageNew = [info objectForKey:@"UIImagePickerControllerOriginalImage"];

    //設定image的尺寸

    CGSize imagesize = imageNew.size;

    imagesize.height =626;

    imagesize.width =413;

    //對圖片大小進行壓縮--

    imageNew = [self imageWithImage:imageNew scaledToSize:imagesize];

    NSData *imageData = UIImageJPEGRepresentation(imageNew,0.00001);

   if(m_selectImage==nil)

    {

        m_selectImage = [UIImage imageWithData:imageData];

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

        [self.TakePhotoBtn setImage:m_selectImage forState:UIControlStateNormal];

        [picker dismissModalViewControllerAnimated:YES];

       return ;

    }

    [picker release];

}

//對圖片尺寸進行壓縮--

-(UIImage*)imageWithImage:(UIImage*)image scaledToSize:(CGSize)newSize

{

    // Create a graphics image context

    UIGraphicsBeginImageContext(newSize);

   
    // Tell the old image to draw in this new context, with the desired

    // new size

    [image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];

   
    // Get the new image from the context

    UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();

   
    // End the context

    UIGraphicsEndImageContext();

   
    // Return the new image.

   return newImage;

}

 

圖片儲存到本地document裡面--以及圖片格式的轉換

IOS開發之儲存圖片到Documents目錄及PNG，JPEG格式相互轉換- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary*)info {

    NSString *mediaType = [info objectForKey:UIImagePickerControllerMediaType];

    if ([mediaType isEqualToString:@"public.image"]){

        image = [info objectForKey:@"UIImagePickerControllerOriginalImage"];

        NSData *data;

        if (UIImagePNGRepresentation(image) == nil) {

            data = UIImageJPEGRepresentation(image, 1);

        } else {

            data = UIImagePNGRepresentation(image);

        }

       

        NSFileManager *fileManager = [NSFileManager defaultManager];

        NSString *filePath = [NSString stringWithString:[self getPath:@"image1"]];         //將圖片儲存到本地documents

 

         [fileManager createDirectoryAtPath:filePath withIntermediateDirectories:YES attributes:nil error:nil];

         [fileManager createFileAtPath:[filePath stringByAppendingString:@"/image.png"] contents:dataattributes:nil];

       

        UIImage *editedImage = [[UIImage alloc] init];

        editedImage = image;

        CGRect rect = CGRectMake(0, 0, 64, 96);

        UIGraphicsBeginImageContext(rect.size);

        [editedImage drawInRect:rect];

        editedImage = UIGraphicsGetImageFromCurrentImageContext();

       

        UIButton *imageButton = [UIButton buttonWithType:UIButtonTypeCustom];

        imageButton.frame = CGRectMake(10, 10, 64, 96);

        [imageButton setImage:editedImage forState:UIControlStateNormal];

        [self.view addSubview:imageButton];

        [imageButton addTarget:self action:@selector(imageAction:)forControlEvents:UIControlEventTouchUpInside];

 

        [ipc dismissModalViewControllerAnimated:YES];

    } else {

        NSLog(@"MEdia");

    }

   

上面的代碼是當從相簿裡面選取圖片之後儲存到本地程式沙箱，在上面我們得到的圖片中不能夠得到圖片名字，以及不清楚圖片格式，所以這個時候我們需要將其轉換成NSdata二進位儲存，

 image = [info objectForKey:@"UIImagePickerControllerOriginalImage"];

NSData *data;

        if (UIImagePNGRepresentation(image) == nil) {

            data = UIImageJPEGRepresentation(image, 1);

        } else {

            data = UIImagePNGRepresentation(image);

        }

UIImagePNGRepresentation轉換PNG格式的圖片為二進位，如果圖片的格式為JPEG則返回nil；

 [fileManager createFileAtPath:[filePath stringByAppendingString:@"/image.png"] contents:data attributes:nil];    將圖片儲存為PNG格式

 [fileManager createFileAtPath:[filePath stringByAppendingString:@"/image.jpg"] contents:data attributes:nil];   將圖片儲存為JPEG格式

 

 

我們也可以寫成下面的格式儲存圖片

NSString *pngImage = [filePath stringByAppendingPathComponent:@"Documents/image.png"];

NSString *jpgImage = [filePath stringByAppendingPathComponent:@"Documents/image.jpg"];

 

 

[data writeToFile:pngImage atomically:YES];

[data writeToFile:jpgImage atomically:YES];