Custom Upload Path by File Type

Use this code, but first of all make sure you set path —( on ),
year/month — ( off ) in your plugin admin settings, then the code.

// the priority for this filter must be less than 100.
add_filter( 'wp_update_attachment_metadata','wp_update_attachment_metadata_2', 90, 2 );
function wp_update_attachment_metadata_2( $data, $post_id ) {
	$type = get_post_mime_type( $post_id );
	$type = explode( '/', $type );
	$ext = $type[ sizeof( $type ) - 1 ];
	$folder = '';
	$img_exts = array( 'jpg', 'jpeg', 'png', 'gif' );
	if ( in_array( $ext, $img_exts ) ) {
		$folder = 'img';
	} elseif ( $ext == 'pdf' ) {
		$folder = 'pdf';
	} else {
		$folder = 'misc';
	}

	if ( $folder ) {
		add_filter( 'as3cf_setting_object-prefix','dynamic_path_'.$folder, 10,1 );
	}
	return $data;
}

function dynamic_path_img( $value ) {
	return 'img';
}

function dynamic_path_pdf ( $value ) {
	return 'pdf';
}

function dynamic_path_misc ( $value ) {
	return 'misc';
}

And Of course you can adjust the folders on s3,for example, returning this string for image file ‘upload/img’ will store your images in folder ‘upload ‘under ‘img’ subfolder on s3.

Thanks! The snippet works perfectly. I really appreciate it.