Wordpress image resize dynamically

fn.php

<?php
/**
	 * @param array $params
	 *
	 * @since 4.2
	 * ifo_filters : ifo_ifoods_getimagesize - to override output of this function
	 * @return array|bool
	 */
	function ifoods_getImageBySize( $params = array() ) {
		$params = array_merge( array(
			'post_id' => null,
			'attach_id' => null,
			'thumb_size' => 'thumbnail',
			'class' => '',
			), $params );

		if ( ! $params['thumb_size'] ) {
			$params['thumb_size'] = 'thumbnail';
		}

		if ( ! $params['attach_id'] && ! $params['post_id'] ) {
			return false;
		}

		$post_id = $params['post_id'];

		$attach_id = $post_id ? get_post_thumbnail_id( $post_id ) : $params['attach_id'];
		$thumb_size = $params['thumb_size'];
		$thumb_class = ( isset( $params['class'] ) && '' !== $params['class'] ) ? $params['class'] . ' ' : '';

		global $_wp_additional_image_sizes;
		$thumbnail = '';

		if ( is_string( $thumb_size ) && ( ( ! empty( $_wp_additional_image_sizes[ $thumb_size ] ) && is_array( $_wp_additional_image_sizes[ $thumb_size ] ) ) || in_array( $thumb_size, array(
			'thumbnail',
			'thumb',
			'medium',
			'large',
			'full',
			) ) )
			) {
			$attributes = array( 'class' => $thumb_class . 'attachment-' . $thumb_size );
		$thumbnail = wp_get_attachment_image( $attach_id, $thumb_size, false, $attributes );
	} elseif ( $attach_id ) {
		if ( is_string( $thumb_size ) ) {
			preg_match_all( '/\d+/', $thumb_size, $thumb_matches );
			if ( isset( $thumb_matches[0] ) ) {
				$thumb_size = array();
				if ( count( $thumb_matches[0] ) > 1 ) {
						$thumb_size[] = $thumb_matches[0][0]; // width
						$thumb_size[] = $thumb_matches[0][1]; // height
					} elseif ( count( $thumb_matches[0] ) > 0 && count( $thumb_matches[0] ) < 2 ) {
						$thumb_size[] = $thumb_matches[0][0]; // width
						$thumb_size[] = $thumb_matches[0][0]; // height
					} else {
						$thumb_size = false;
					}
				}
			}
			if ( is_array( $thumb_size ) ) {
				// Resize image to custom size
				$p_img = ifo_resize( $attach_id, null, $thumb_size[0], $thumb_size[1], true );
				$alt = trim( strip_tags( get_post_meta( $attach_id, '_wp_attachment_image_alt', true ) ) );
				$attachment = get_post( $attach_id );
				if ( ! empty( $attachment ) ) {
					$title = trim( strip_tags( $attachment->post_title ) );

					if ( empty( $alt ) ) {
						$alt = trim( strip_tags( $attachment->post_excerpt ) ); // If not, Use the Caption
					}
					if ( empty( $alt ) ) {
						$alt = $title;
					} // Finally, use the title
					if ( $p_img ) {

						$attributes = ifo_stringify_attributes( array(
							'class' => $thumb_class,
							'src' => $p_img['url'],
							'width' => $p_img['width'],
							'height' => $p_img['height'],
							'alt' => $alt,
							'title' => $title,
							) );

						$thumbnail = '<img ' . $attributes . ' />';
					}
				}
			}
		}

		$p_img_large = wp_get_attachment_image_src( $attach_id, 'large' );


		return apply_filters( 'ifo_ifoods_getimagesize', array(
			'thumbnail' => $thumbnail,
			'p_img_large' => $p_img_large,
			'p_img' => $p_img['url'],
			), $attach_id, $params );
	}

	/*
	* Resize images dynamically using wp built in functions
	* Victor Teixeira
	*
	* php 5.2+
	*
	* Exemplo de uso:
	*
	* <?php
	* $thumb = get_post_thumbnail_id();
	* $image = vt_resize( $thumb, '', 140, 110, true );
	* ?>
	* <img src="<?php echo $image[url]; ?>" width="<?php echo $image[width]; ?>" height="<?php echo $image[height]; ?>" />
	*
	*/
	if ( ! function_exists( 'ifo_resize' ) ) {
		/**
		 * @param int $attach_id
		 * @param string $img_url
		 * @param int $width
		 * @param int $height
		 * @param bool $crop
		 *
		 * @since 4.2
		 * @return array
		 */
		function ifo_resize( $attach_id = null, $img_url = null, $width, $height, $crop = false ) {
			// this is an attachment, so we have the ID
			$image_src = array();
			if ( $attach_id ) {
				$image_src = wp_get_attachment_image_src( $attach_id, 'full' );
				$actual_file_path = get_attached_file( $attach_id );
				// this is not an attachment, let's use the image url
			} elseif ( $img_url ) {
				$file_path = parse_url( $img_url );
				$actual_file_path = rtrim( ABSPATH, '/' ) . $file_path['path'];
				$orig_size = getimagesize( $actual_file_path );
				$image_src[0] = $img_url;
				$image_src[1] = $orig_size[0];
				$image_src[2] = $orig_size[1];
			}
			if ( ! empty( $actual_file_path ) ) {
				$file_info = pathinfo( $actual_file_path );
				$extension = '.' . $file_info['extension'];

				// the image path without the extension
				$no_ext_path = $file_info['dirname'] . '/' . $file_info['filename'];

				$cropped_img_path = $no_ext_path . '-' . $width . 'x' . $height . $extension;

				// checking if the file size is larger than the target size
				// if it is smaller or the same size, stop right here and return
				if ( $image_src[1] > $width || $image_src[2] > $height ) {

					// the file is larger, check if the resized version already exists (for $crop = true but will also work for $crop = false if the sizes match)
					if ( file_exists( $cropped_img_path ) ) {
						$cropped_img_url = str_replace( basename( $image_src[0] ), basename( $cropped_img_path ), $image_src[0] );
						$vt_image = array(
							'url' => $cropped_img_url,
							'width' => $width,
							'height' => $height,
						);

						return $vt_image;
					}

					if ( false == $crop ) {
						// calculate the size proportionaly
						$proportional_size = wp_constrain_dimensions( $image_src[1], $image_src[2], $width, $height );
						$resized_img_path = $no_ext_path . '-' . $proportional_size[0] . 'x' . $proportional_size[1] . $extension;

						// checking if the file already exists
						if ( file_exists( $resized_img_path ) ) {
							$resized_img_url = str_replace( basename( $image_src[0] ), basename( $resized_img_path ), $image_src[0] );

							$vt_image = array(
								'url' => $resized_img_url,
								'width' => $proportional_size[0],
								'height' => $proportional_size[1],
							);

							return $vt_image;
						}
					}

					// no cache files - let's finally resize it
					$img_editor = wp_get_image_editor( $actual_file_path );

					if ( is_wp_error( $img_editor ) || is_wp_error( $img_editor->resize( $width, $height, $crop ) ) ) {
						return array(
							'url' => '',
							'width' => '',
							'height' => '',
						);
					}

					$new_img_path = $img_editor->generate_filename();

					if ( is_wp_error( $img_editor->save( $new_img_path ) ) ) {
						return array(
							'url' => '',
							'width' => '',
							'height' => '',
						);
					}
					if ( ! is_string( $new_img_path ) ) {
						return array(
							'url' => '',
							'width' => '',
							'height' => '',
						);
					}

					$new_img_size = getimagesize( $new_img_path );
					$new_img = str_replace( basename( $image_src[0] ), basename( $new_img_path ), $image_src[0] );

					// resized output
					$vt_image = array(
						'url' => $new_img,
						'width' => $new_img_size[0],
						'height' => $new_img_size[1],
					);

					return $vt_image;
				}

				// default output - without resizing
				$vt_image = array(
					'url' => $image_src[0],
					'width' => $image_src[1],
					'height' => $image_src[2],
				);

				return $vt_image;
			}

			return false;
		}
	}

	/**
	 * Convert array of named params to string version
	 * All values will be escaped
	 *
	 * E.g. f(array('name' => 'foo', 'id' => 'bar')) -> 'name="foo" id="bar"'
	 *
	 * @param $attributes
	 *
	 * @return string
	 */
	function ifo_stringify_attributes( $attributes ) {
		$atts = array();
		foreach ( $attributes as $name => $value ) {
			$atts[] = $name . '="' . esc_attr( $value ) . '"';
		}

		return implode( ' ', $atts );
	}

usage.php

<?php
$img_size = '380x380';
$img = ifoods_getImageBySize( array(
		'attach_id' => get_post_thumbnail_id(),
		'thumb_size' => $img_size,
		'class' => 'vc_single_image-img',
	) );