Failed to display images from the web folder

I have succeeded in uploading an image and saving it to the database. I generate a random string after saving the image in the database and in the images folder under web/uploads/images. I have failed to display the images on the web yet other images can show corrrectly. Any idea?

This is my controller
public function actionUploadPicture()
{
$model = $this->findModel(Yii::$app->user->id);
$model->scenario = ‘picture’;

    if ($model->load(Yii::$app->request->post())) {
        $image = UploadedFile::getInstance($model, 'image');
        if (!is_null($image)) {
            $model->image_src_filename = $image->name;
            $file_extension = explode(".", $image->name);
            $ext   = end($file_extension);
            // generate a unique file name to prevent duplicate filenames
            $model->image_web_filename = Yii::$app->security->generateRandomString().".{$ext}";
            // the path to save file, you can set an uploadPath

            Yii::$app->params['uploadPath'] = Yii::$app->basePath . '/web/uploads/images/';
            $path = Yii::$app->params['uploadPath'] . $model->image_web_filename;
            $image->saveAs($path);
        }
        if ($model->save(false)) {
            return $this->redirect(['view', 'id' => $model->id]);
        }  else {
            var_dump ($model->getErrors()); die();
        }
    }
    return $this->render('signup', [
        'model' => $model,
    ]);
}

And this is my view.

<h1><?= Html::encode($this->title) ?></h1>

<?= DetailView::widget([
    'model' => $model,
    'attributes' => [
            'firstname',
        'lastname',
        'username',
        'email',
        'mobile_phone',
        'user_level',
        'created_at',
        'updated_at',
        'image_web_filename',
        'image_src_filename',
    ],

]) ?>

<?php
if ($model->image_web_filename!='') {

  echo  Html::a(Html::img(Yii::getAlias('@web').'/uploads/images/'.$model->image_web_filename, ['alt'=>'somepic']));

}
?>

Do you have the image in question in the file system? If the directory in question accessible to web server?