How to get the correct link to the image from the post?

Good afternoon. Posts from a group page to classmates read api. If to the post the image is attached instead of the link to the image that it returns a reference to the preloader. Can anyone explain this behavior of the api? Is there any possibility to get the link to the attached picture?
The following is information on the request and response api.
Make a request discussions.get
In response to receiving the json in which the elements of
{
"discussion": {
"title": "sbeve 1",
"message": "Topic",
"object_type": "GROUP_TOPIC",
"object_id": "123",
"creation_date": "2019-03-27 11:18:23",
"last_activity_date": "1970-01-01 02:59:59",
"last_user_access_date": "1970-01-01 02:59:59",
"new_comments_count": 0,
"total_comments_count": 0,
"like_count": 0,
"liked_it": false,
"ref_objects": [
{
"type": "GROUP",
"id": "123"
}
],
"attrs": {
"flags": "c,l,s,unsb"
}
},
"entities": {
"themes": [
{
"id": "123",
"title": "sbeve 1",
"images": [
{
"type": "group",
"id": "123",
"pic50x50": "https://i.mycdn.me/image?id=867891877674&t=32&plc=...",
"pic128x128": "https://i.mycdn.me/image?id=867891877674&t=23&plc=...",
"pic640x480": "https://i.mycdn.me/image?id=867891877674&t=0&plc=A...",
"group_id": "123",
"author_type": "GROUP"
}
],
"attrs": {
"p": 1
}
}
],
"groups": [
{
"uid": "123",
"name": "Group"
}
]
}
}
March 19th 20 at 08:48
0 answer

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