Angular 12 image crop and upload with npm ngx-image-cropper example; In this tutorial, i am going to show you on how to show image preview by creating a Base64 url in angular before upload. And as well as how to crop an image in angular, how to zoom the image, and how to scale the image in Angular.
Crop image is great feature for server space optimization. Crop image will resize image as per required size while uploading on the server. Crop image will reduce image size and optimize image before uploading to the server. Crop image will upload image with our required width and height.
Angular 12 Image Upload, Preview, Crop, Zoom and Scale Tutorial
- Step 1 – Create New Angular App
- Step 2 – Install ngx-image-cropper and Bootstrap Library
- Step 3 – Import Modules on App.Module.ts File
- Step 4 – Add Code on View File
- Step 5 – Add Code On app.Component ts File
- Step 6 – Start the Angular App
Step 1 – Create New Angular App
First of all, open your terminal and execute the following command on it to install angular app:
ng new my-new-app
Step 2 – Install ngx-image-cropper and Bootstrap Library
Then install bootstrap library for implement image crop and upload in angular app. So, You can install the packages by executing the following commands on the terminal:
npm install bootstrap
Include bootstrap css into angular.json file:
... ... "styles": [ "src/styles.scss", "node_modules/bootstrap/dist/css/bootstrap.min.css" ], ... ...
Once you created a new angular app and entered into the project further, you have to install and add the image cropper plugin into the angular app:
npm install ngx-image-cropper
Step 3 – Import Modules on App.Module.ts File
Go to src/directory and open app.module.ts file. And then add the following lines of into app.module.ts file:
import { NgModule } from '@angular/core'; import { BrowserModule } from '@angular/platform-browser'; import { AppRoutingModule } from './app-routing.module'; import { AppComponent } from './app.component'; import { ImageCropperModule } from 'ngx-image-cropper'; @NgModule({ declarations: [ AppComponent ], imports: [ BrowserModule, AppRoutingModule, ImageCropperModule ], providers: [], bootstrap: [AppComponent] }) export class AppModule { }
Step 4 – Add Code on View File
Ceate image upload form in angular 12 app. So, go to src/ and app.component.html and update the following code into it:
<div class="container mt-5 text-center"> <h3 class="mb-5">Angular Image Crop Example - Laratutorials.com</h3> <div class="col-md-12"> <input type="file" (change)="onFileChange($event)" /> </div> <div class="col-md-8"> <image-cropper [imageChangedEvent]="imgChangeEvt" [maintainAspectRatio]="true" [aspectRatio]="4 / 4" [resizeToWidth]="256" format="png" (imageCropped)="cropImg($event)" (imageLoaded)="imgLoad()" (cropperReady)="initCropper()" (loadImageFailed)="imgFailed()"> </image-cropper> </div> <div class="col-md-4"> <h6>Image Preview</h6> <img [src]="cropImgPreview" /> </div> </div>
Step 5 – Add Code On app.Component ts File
Go to src/ directory and open app.component.ts. Then add the following code into component.ts file:
import { Component } from '@angular/core'; import { ImageCroppedEvent } from 'ngx-image-cropper'; @Component({ selector: 'app-root', templateUrl: './app.component.html', styleUrls: ['./app.component.scss'] }) export class AppComponent { imgChangeEvt: any = ''; cropImgPreview: any = ''; onFileChange(event: any): void { this.imgChangeEvt = event; } cropImg(e: ImageCroppedEvent) { this.cropImgPreview = e.base64; } imgLoad() { // display cropper tool } initCropper() { // init cropper } imgFailed() { // error msg } }
Step 6 – Start the Angular App
Execute the following command on terminal to start angular app:
ng serve
All features and methods of ngx-image-cropper
All inputs are optional. Either the imageChangedEvent
, imageBase64
or imageFile
should be set to load an image into the cropper.
Inputs
Name | Type | Default | Description |
---|---|---|---|
imageChangedEvent | FileEvent | The change event from your file input (set to null to reset the cropper) | |
imageFile | Blob(File) | The file you want to change (set to null to reset the cropper) | |
imageBase64 | string | If you don’t want to use a file input, you can set a base64 image directly and it will be loaded into the cropper | |
imageURL | string | If you don’t want to use a file input or a base64 you can set an URL to get the image from. If requesting an image from a different domain make sure Cross-Origin Resource Sharing (CORS) is allowed or the image will fail to load. | |
format | string | png | Output format (png, jpeg, webp, bmp, ico) (not all browsers support all types, png is always supported, others are optional) |
aspectRatio | number | 1 / 1 | The width / height ratio (e.g. 1 / 1 for a square, 4 / 3, 16 / 9 …) |
maintainAspectRatio | boolean | true | Keep width and height of cropped image equal according to the aspectRatio |
containWithinAspectRatio | boolean | false | When set to true, padding will be added around the image to make it fit to the aspect ratio |
resizeToWidth | number | 0 (disabled) | Cropped image will be resized to at most this width (in px) |
resizeToHeight | number | 0 (disabled) | Cropped image will be resized to at most this height (in px) |
cropperStaticWidth | number | 0 (disabled) | Set Cropper Width and disable resize (in px) |
cropperStaticHeight | number | 0 (disabled) | Set Cropper Height and disable resize (in px) |
cropperMinWidth | number | 0 (disabled) | The cropper cannot be made smaller than this number of pixels in width (relative to original image’s size) (in px) |
cropperMinHeight | number | 0 (disabled) | The cropper cannot be made smaller than this number of pixels in height (relative to original image’s size) (in px) (will be ignored if maintainAspectRatio is set) |
cropperMaxWidth | number | 0 (disabled) | The cropper cannot be made bigger than this number of pixels in width (in px) |
cropperMaxHeight | number | 0 (disabled) | The cropper cannot be made bigger than this number of pixels in height (in px) |
initialStepSize | number | 3 (px) | The initial step size in pixels when moving the cropper using the keyboard. Step size can then be changed by using the numpad when the cropper is focused |
onlyScaleDown | boolean | false | When the resizeToWidth or resizeToHeight is set, enabling this option will make sure smaller images are not scaled up |
cropper | CropperPosition | To be able to overwrite the cropper coordinates, you can use this input. Create a new object of type CropperPosition and assign it to this input. Make sure to create a new object each time you wish to overwrite the cropper’s position and wait for the cropperReady event to have fired. | |
roundCropper | boolean | false | Set this to true for a round cropper. Resulting image will still be square, use border-radius: 100% on resulting image to show it as round. |
imageQuality | number | 92 | This only applies when using jpeg or webp as output format. Entering a number between 0 and 100 will determine the quality of the output image. |
autoCrop | boolean | true | When set to true, the cropper will emit an image each time the position or size of the cropper is changed. When set to false, you can call the crop method yourself (use @ViewChild to get access to the croppers methods). |
alignImage | ‘left’ or ‘center’ | ‘center’ | Use this to align the image in the cropper either to the left or center. |
backgroundColor | string | Use this to set a backgroundColor, this is useful if you upload an image of a format with transparent colors and convert it to ‘jpeg’ or ‘bmp’. The transparent pixels will then become the set color or the default value. Enter any string representing a CSS color (https://developer.mozilla.org/en-US/docs/Web/CSS/color_value). | |
hideResizeSquares | boolean | false | Disables the resize-squares at the border of the cropper. This is mostly useful for Touch Devices where you can change the Size of the Cropper via Pinch-To-Zoom |
disabled | boolean | false | Disables the component and prevents changing the cropper position |
canvasRotation | number | 0 | Rotate the canvas (1 = 90deg, 2 = 180deg…) |
transform | ImageTransform | {} | Flip, rotate and scale image |
CSS Variables
Name | Type | Default | Description |
---|---|---|---|
--cropper-outline-color | string | rgba(255,255,255,0.3) | The background color you see around the cropper |
--cropper-overlay-color | string | rgba(255,255,255) | The background color you see around the image |
Outputs
Name | Type | Description |
---|---|---|
imageCropped | ImageCroppedEvent | Emits an ImageCroppedEvent each time the image is cropped |
imageLoaded | LoadedImage | Emits the LoadedImage when it was loaded into the cropper |
cropperReady | Dimensions | Emits when the cropper is ready to be interacted. The Dimensions object that is returned contains the displayed image size |
startCropImage | void | Emits when the component started cropping the image |
loadImageFailed | void | Emits when a wrong file type was selected (only png, gif and jpg are allowed) |
Methods
To gain access to the image cropper’s methods use @ViewChild(ImageCropperComponent) imageCropper: ImageCropperComponent;
Name | Returns | Description |
---|---|---|
crop | ImageCroppedEvent | Crops the source image to the current cropper position. Be sure to set autoCrop to false if you only wish to use this function directly. |
Interfaces
CropperPosition
Property | Type | Description |
---|---|---|
x1 | number | X position of first coordinate (in px) |
y1 | number | Y position of first coordinate (in px) |
x2 | number | X position of second coordinate (in px) |
y2 | number | Y position of second coordinate (in px) |
ImageTransform
Property | Type | Description |
---|---|---|
scale | number | Scale image (1=normal, 2=2x zoom…) |
rotate | number | Rotation in degrees |
flipH | boolean | Flipped horizontally |
flipV | boolean | Flipped vertically |
ImageCroppedEvent
Property | Type | Description |
---|---|---|
base64 | string | Base64 string of the cropped image |
width | number | Width of the cropped image |
height | number | Height of the cropped image |
cropperPosition | CropperPosition | Position of the cropper when it was cropped relative to the displayed image size |
imagePosition | CropperPosition | Position of the cropper when it was cropped relative to the original image size |
offsetImagePosition | CropperPosition | Position of the cropper when it was cropped relative to the original image size without padding when containWithinAspectRatio is true |
LoadedImage
Property | Type | Description |
---|---|---|
original.base64 | string | Base64 string of the original image |
original.image | HTMLImageElement | HTMLImageElement of the original image |
original.size | Dimension | Width and height of the original image |
transformed.base64 | string | Base64 string of the transformed image |
transformed.image | HTMLImageElement | HTMLImageElement of the transformed image |
transformed.size | Dimension | Width and height of the transformed image |
exifTransform | ExifTransform | Exif transformations read from original image |