seems to work for now. GET / will return HTML and via POST / one can upload an image and will get the pixelated result as binary stream

1 year ago · 9e3cf97a63
4 changed files with 106 additions and 0 deletions
--- a/README.md
+++ b/README.md
@ -0,0 +1,10 @@
+# pixelate via API
+
+Setup:
+```bash
+python3 -m venv venv
+source venv/bin/activate
+pip install -r requirements.txt
+uvicorn main:app --reload
+```
+and go to http://localhost:8000
--- a/fileutils.py
+++ b/fileutils.py
@ -0,0 +1,7 @@
+from pathlib import Path
+
+VALID_FILE_FORMATS = [".jpg",".jpeg",".png"]
+
+
+def has_valid_suffix(file):
+    return Path(file).suffix.lower() in VALID_FILE_FORMATS
--- a/img_proc.py
+++ b/img_proc.py
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+import numpy as np
+from PIL import Image, ImageEnhance
+import io
+
+def pixelate(img_name: str,
+             saturation: float = 1.25,
+             contrast: float = 1.2,
+             n_colors: int = 10,
+             superpixel_size: int = 10):
+    """
+    See: https://github.com/ferretj/pixelate
+    """
+
+    img = Image.open(img_name)
+    img_size = img.size
+
+    # boost saturation of image
+    sat_booster = ImageEnhance.Color(img)
+    img = sat_booster.enhance(saturation)
+
+    # increase contrast of image
+    contr_booster = ImageEnhance.Contrast(img)
+    img = contr_booster.enhance(contrast)
+
+    # reduce the number of colors used in picture
+    img = img.convert('P', palette=Image.ADAPTIVE, colors=n_colors)
+    # reduce image size
+    reduced_size = (img_size[0] // superpixel_size, img_size[1] // superpixel_size)
+    img = img.resize(reduced_size, Image.BICUBIC)
+
+    # resize to original shape to give pixelated look
+    img = img.resize(img_size, Image.BICUBIC)
+
+    return img
+
+
+def img2byte(img:Image):
+    imgByteArr = io.BytesIO()
+    img.save(imgByteArr, format="PNG")
+    imgByteArr = imgByteArr.getvalue()
+    return imgByteArr
+
+if __name__ == '__main__':
+    img =  pixelate("img.jpg")
+    img.save("out.png")
--- a/main.py
+++ b/main.py
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+from fastapi import FastAPI, File, UploadFile, Response, HTTPException
+from fastapi.responses import HTMLResponse
+from img_proc import pixelate, img2byte
+import fileutils as fu
+
+app = FastAPI()
+
+
+@app.get("/", response_class=HTMLResponse, include_in_schema=False)
+async def root_html():
+    return """
+    <html>
+        <head>
+            <title>pixelate via API</title>
+        </head>
+        <body>
+            <h2>pixelate</h2>
+            <strong> go to <a href="/docs"> /docs</a> for OpenAPI docs </strong>
+            <p>based on: <a href="https://github.com/ferretj/pixelate">https://github.com/ferretj/pixelate</a> </p>
+        </body>
+    </html>
+    """
+
+@app.post("/")
+async def root(saturation: float = 1.5,
+               contrast: float = 1.2,
+               n_colors: int = 10,
+               superpixel_size: int = 15,
+               file: UploadFile = File(...)):
+    """
+    saturation: float = 1.25,
+    contrast: float = 1.2,
+    n_colors: int = 10,
+    superpixel_size: int = 10,
+    """
+    if not fu.has_valid_suffix(file.filename):
+        raise HTTPException(status_code=400,
+                            detail="Invalid file ending! Only {} accepted".fomrat(fs.VALID_FILE_FORMATS))
+    out_img = pixelate(file.file,
+                        saturation = saturation,
+                        contrast = contrast,
+                        n_colors = n_colors,
+                        superpixel_size = superpixel_size)
+    return Response(content=img2byte(out_img), media_type="image/png")