Lightweight image cropping with jQuery

.gitignore

# Ignore everything in this directory
*
# Except this file
!.gitignore

code-preview.jpg

form.html

<!-- Elsewhere on your document -->
<button class="btn btn-info" id="showAvatar">Change Photo</button>

<!-- the modal code -->
<div id="avatar" class="modal fade">
    <div class="modal-dialog">
        <div class="modal-content">
            <div class="modal-header">
                <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>
                <h4 class="modal-title">Profile Picture</h4>
            </div>
            <form method="POST" action="your-avatar-url" accept-charset="UTF-8" enctype="multipart/form-data">
                <input name="_token" type="hidden" value="your-token-value">
                <div class="modal-body">
                        <!-- crop data -->
                            <!-- points for cropping -->
                            <input type="hidden" name="x" />
                            <input type="hidden" name="y" />
                            <!-- the size of the crop window -->
                            <input type="hidden" name="width" />
                            <input type="hidden" name="height" />
                            <!-- the size that the full size image needs to
                                be resized to before cropping due to the use
                                 of width:100% and how it affects the size/x,y
                                 points of the crop -->
                            <input type="hidden" name="img-width" />
                            <input type="hidden" name="img-height" />
                        <div class="row">
                            <div class="col-md-12">
                                <h5>Step 1: Select a photo (at least 140px by 140px)</h5>
                                <input type="file" name="avatar" />
                            </div>
                            <div class="col-md-12">
                                <div class="errors"></div>
                            </div>
                            <div class="col-md-12 step2">
                                <h5>Step2: Select a crop region</h5>
                                <div class="preview-container">
                                    <img class="preview" />
                                </div>
                            </div>
                        </div>
                </div>
                <div class="modal-footer">
                    <button type="button" class="btn btn-default" data-dismiss="modal">Cancel</button>
                    <button type="submit" class="btn btn-primary">Save</button>
                </div>
            </form>
        </div><!-- /.modal-content -->
    </div><!-- /.modal-dialog -->
</div><!-- /.modal -->

functions.js

$(function() {
    $input = $('#avatar input:file');
    $form = $input.closest('form');
    $errors = $('#avatar .errors');
    $step2 = $form.find('.step2');
    $previewContainer = $form.find('.preview-container');

    $form.submit(function(e){
        $errors.hide();
        if(typeof $file == 'undefined') {
            e.preventDefault();
            $errors.text('Select an image and crop it first!').show();
            throw 'Select an image and crop it first!';
        }
        if(!$form.find('[name="width"]').val().length) {
            e.preventDefault();
            $errors.text('Select a crop region first!').show();
            throw 'Select a crop region first!';
        }
    });

    $('#showAvatar').click(function(){
        $('#avatar').modal({
            backdrop: 'static',
            keyboard: false
        });
    });

    $('#avatar').on('hidden.bs.modal', function(){
        $form.trigger('reset');
        $step2.hide();
        $previewContainer.empty();
    });

    $input.on('change', function () {
        $step2.hide();
        $file = $input[0].files[0];
        $allowed = ['image/jpeg', 'image/png'];

        // check if image is actually an accepted image type
        if($.inArray($file.type, $allowed) == -1) {
            $errors.text('Invalid file type! JPG(JPEG) and PNG only!').show();
            throw 'Invalid file type! JPG(JPEG) and PNG only!';
        }

        // 3MB limit on images
        if($file.size > 3 * 1024 * 1024) {
            $errors.text('The image you have selected is too big! 3MB limit!').show();
            throw 'The image you have selected is too big! 3MB limit!';
        }

        $errors.hide();

        var reader = new FileReader();

        reader.onload = function(e) {

            $previewContainer.html('<img class="preview" src="'+ e.target.result+'" />');

            $preview = $form.find('.preview');

            $preview.on('load change', function(){
                new Cropper(this, {
                    ratio: {
                        width:  1,
                        height: 1
                    },
                    min_width: 140,
                    min_height: 140,
                    max_width: ($preview.width() > $preview.height() ? $preview.height() : $preview.width()),
                    max_height: ($preview.width() > $preview.height() ? $preview.height() : $preview.width()),
                    update: function (coordinates) {
                        for (var i in coordinates) {
                            $form.find('[name="'+i+'"]').val(coordinates[i]);
                        }
                    }
                });
                $form.find('[name="img-width"]').val($preview.width());
                $form.find('[name="img-height"]').val($preview.height());
            });

            $step2.show();

        };

        reader.readAsDataURL($file);
    });

});

laravel-upload.php

// A nice way to manage it on laravel using Intervention Image package
// Also, there needs to be a 'avatar' varchar/string column on users table
// $table->string('avatar')->nullable();
// you should also have an /uploads/avatar directory in your public folder

    public function avatar(Request $request)
    {
        $validator = Validator::make($request->all(), [
            'x' => 'required|numeric',
            'y' => 'required|numeric',
            'width' => 'required|numeric',
            'height' => 'required|numeric',
            'img-width' => 'required|numeric',
            'img-height' => 'required|numeric',
            'avatar' => 'required|image'
        ]);

        if ($validator->fails()) {
            session()->flash('error_msg', 'There was an issue with your avatar! Try again!');

            return redirect()->back();
        }

        if(auth()->user()->avatar) {
            if(File::exists(public_path(auth()->user()->avatar))) {
                File::delete(public_path(auth()->user()->avatar));
            }
        }

        $name = hash("SHA256", env('APP_KEY') . str_random(30) . time());
        $db_location = 'uploads/avatar/' . $name . '.jpg';
        $save_location = public_path('uploads/avatar/') . $name . '.jpg';

        Image::make($request->file('avatar')->getRealPath())
            ->resize($request->input('img-width'), $request->input('img-height'))
            ->crop($request->input('width'), $request->input('height'), $request->input('x'), $request->input('y'))
            ->resize(140, 140)
            ->encode('jpg', 100)
            ->save($save_location, 100);

        $user = User::find(auth()->user()->getAuthIdentifier());
        $user->avatar = $db_location;
        $user->save();

        return redirect()->back();
    }

Lightweight image cropping with jQuery.md

This is a simple implementation of this lightweight image cropping library Pure JavaScript Image Crop Component - wouldn't be hard to implement this free cropping library

Be sure to include the required files cropper.css, cropper.min.js, [functions.js](https://gist.github.com/Kryptonit3/f3e7e29707ed791087c6#file-functions-js)

This assumes you are using bootstrap with modals, and have a button with the ID of showAvatar somewhere on your document to invoke the modal.

When processing on the backend you will have the following inputs to work with:

x & y = the starting crop points
width & height = the size of the crop window
img-width & img-height = the size that the full size image needs to be resized to
                            before cropping due to the use of width:100% and how it 
                            affects the size/x,y points of the crop

You will need to add your action/url to the form and process it how you choose to.

If you are using Laravel you can add this method to your user model

A nice way to manage it on laravel using Intervention Image package Also, there needs to be a 'avatar' varchar/string column on users table add this to a new column migration or your user migration

$table->string('avatar')->nullable();

you should also have an /uploads/avatar directory in your public folder with the following file in it for when pushing to git https://gist.github.com/Kryptonit3/f3e7e29707ed791087c6#file-gitignore

public function avatar()
{
    $avatar = ($this->avatar) ? asset($this->avatar) : asset('img/default-avatar.png');

    return $avatar;
}

Be sure to set the default avatar url ('img/default-avatar.png') for users who have not set theirs.

Then in your loops you can do

@foreach($users as $user)
    <img src="{{ $user->avatar() }}" alt="{{ $user->username }}" />
@endforeach

That way if you ever change the structure of how your avatars are fetched, you only need to update your method on your User model.

Here is a method for uploading the image to the filesystem

If you have any questions, ask away in the comments! :)

modal-step-1.jpg

modal-step-2-a.jpg

modal-step-2-b.jpg

profile_picture_button.jpg

sample-error.jpg

style.css

.step2,.errors{display:none}
.errors{background:#e74430;color:#fff;padding:6px 10px;margin:10px 0;}
.preview{max-width:100%;max-height:600px;}

step 2 i have getting the error, not showing the cropper