bbPress.org

This works for me :

1) Add this to function.php in your child theme

via http://bavotasan.com/2014/add-media-upload-button-to-bbpress/

Open up your functions.php file and add the following snippet to get it working:

add_filter( 'bbp_after_get_the_content_parse_args', 'bavotasan_bbpress_upload_media' );
/**
 * Allow upload media in bbPress
 *
 * This function is attached to the 'bbp_after_get_the_content_parse_args' filter hook.
 */
function bavotasan_bbpress_upload_media( $args ) {
	$args['media_buttons'] = true;

	return $args;
}

So now you have the Add Media button in the posting

2) What you need now is to fine tune the user capabilities so that not only administrators but normal users can upload media direct to the form post using the Add Media button

I am using the Capability Manager Enhanced plugin

https://wordpress.org/plugins/capability-manager-enhanced

I guess you could use a Custom user type (e.g. clone the normal participants) to experiment. Later on you could edit all your users and convert them to this Custom user type

Check the ability to:

a) Upload files
b) Unfiltered HTML

for this Custom user type

I guess it comes with risks but it has the benefits of direct Media upload to the bbPress forum

It’s not only images but other media e.g. PDF (which works nicely with thhe Google Doc Embedder Plugin