Create Ticket with Image Zammad v2.5

I would like to create a ticket via REST API.
The application via curl works, but if I hang pictures with it, I can not open the pictures in the ticket.
Text files can be viewed from the ticket.
I hand over the data as follows:

$ticket = array(
“title” => $data[‘betreff’],
“group_id” => $data[‘bereich’],
“priority_id” => 2,
“customer” => $data[‘email’],
“php_datei” => $data[‘php_datei’],
“article” => array(
“body” => $data[‘beschreibung’],
“type” => “note”,
“subject” => $data[‘betreff’],
“internal” => false
),
“note” => $data[‘beschreibung’]

);
foreach ($pictures as $picture) {
    $ticket['article']['attachments'][] = array(
        "filename" => $picture['name'],
        "data" => base64_encode(make_iso($picture['content'])),
        "mime-type" => 'application/octet-stream'
    );
}

curl_setopt($curl, CURLOPT_POSTFIELDS, json_encode($ticket));

I have nowhere in the documentation found anything with uploading images, maybe “mime-type” is not right.

Über eine Hilfe währe ich sehr dankbar.

3rd search result on Google:
https://docs.zammad.org/en/latest/api-ticket.html#create

Another possible hint:

The provided information is quite well… small.
The Zammad logfile nearly always helps you and might contain further information on why something does not work. You also did not porvide the API response.

Maybe the above links help you.
Oh and edit: Asking for help on community