preview current image when opts.show_progress_every_n_steps is enabled

modules/api/api.py

 import time
 import uvicorn
 from gradio.processing_utils import encode_pil_to_base64, decode_base64_to_file, decode_base64_to_image
-from fastapi import APIRouter, HTTPException
+from fastapi import APIRouter, Depends, HTTPException
 import modules.shared as shared
 from modules import devices
 from modules.api.models import *
@@ -187,7 +187,11 @@ class Api:
 
         progress = min(progress, 1)
 
-        return ProgressResponse(progress=progress, eta_relative=eta_relative, state=shared.state.dict())
+        current_image = None
+        if shared.state.current_image:
+            current_image = encode_pil_to_base64(shared.state.current_image)
+
+        return ProgressResponse(progress=progress, eta_relative=eta_relative, state=shared.state.dict(), current_image=current_image)
 
     def launch(self, server_name, port):
         self.app.include_router(self.router)

modules/api/models.py

@@ -161,3 +161,4 @@ class ProgressResponse(BaseModel):
     progress: float = Field(title="Progress", description="The progress with a range of 0 to 1")
     eta_relative: float = Field(title="ETA in secs")
     state: dict = Field(title="State", description="The current state snapshot")
+    current_image: str = Field(default=None, title="Current image", description="The current image in base64 format. opts.show_progress_every_n_steps is required for this to work.")