add 5102 overlay images proposal

kinds/5102.md

@@ -0,0 +1,54 @@
+---
+layout: default
+title: Image Overlay
+description: Job request to overlay two images.
+---
+
+# Input
+
+Clients must provide exactly two `"i"` tags specifying the two images to overlay. The supported input types are:
+- `"url"`
+- `"job"` (content field must be a URL)
+
+One of the `"i"` tags must specify the `"background"` [marker](https://github.com/nostr-protocol/nips/blob/master/90.md), which specifies that this input image is used as the  background image.
+
+# Params
+
+## `position`
+
+Description:
+Specifies the position of the "foreground" image relative to the origin point, using an `x:y` coordinate pair denominated in pixels. The origin point (0,0) is the top left corner of the "background" image. 
+
+A higher value in the x-axis means more to the right. A higher value in the y-axis means more downward.  Only positive values are allowed.
+
+
+Usage:
+```
+["param", "position", "x:y"]
+```
+
+Example: position the "foreground" image 50 pixels to the right of the origin, 25 pixels down from the origin.
+```
+["param", "position", "50:25"]
+```
+
+
+# Output
+
+A link to the generated image(s)
+
+# Example 1
+
+## Generates an output image based on the input prompt and params
+
+```json
+{
+    "content": "",
+    "kind": 5102,
+    "tags": [
+        [ "i", "https://some-url.net", "url", "background" ],
+        [ "i", "https://some-thing.net", "url"],
+        ["param", "position", "100:100"]
+    ]
+}
+```