<?php

use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;

class CreateFavoritesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('favorites', function ($table) {
            $table->integer('video_id')->unsigned();
            $table->foreign('video_id')->references('id')->on('videos');

            $table->integer('user_id')->unsigned();
            $table->foreign('user_id')->references('id')->on('users');

            $table->timestamp('registered_at')->useCurrent();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::drop('favorites');
    }
}

<?php

use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;

class CreateFavoritesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('favorites', function (Blueprint $table) {
            $table->integer('video_id', false, true);
            $table->foreign('video_id')->references('id')->on('videos');

            $table->integer('user_id', false, true);
            $table->foreign('user_id')->references('id')->on('users');

            $table->timestamp('registered_at')->useCurrent();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::drop('favorites');
    }
}

Use integer parameter to set the fields unsigned
Use integer parameter to set the fields unsigned
