I Built a PDF to Editable PowerPoint Converter—Here's How I Extract Vector Icons as Editable Shapes

LotusWang — Mon, 06 Apr 2026 03:01:14 +0000

The Problem

You've been there: someone sends you a beautifully designed PDF deck and asks you to "just edit a few slides." You try an online converter, and what do you get? A PowerPoint full of flat images. Every icon, every text box—just a screenshot you can't touch.

I kept hitting this wall, so I built PDFtoDeck—an open-source tool that converts PDF to truly editable PowerPoint files.

What Makes It Different?

Most converters take the easy route: render each PDF page as an image and embed it into a slide. Done. But useless if you need to edit anything.

PDFtoDeck does three things differently:

Text → Editable text boxes with correct positioning, font size, and color
Vector icons → Editable freeform shapes (not bitmaps!)
Layout preservation—spacing, alignment, and visual hierarchy stay intact

The vector icon extraction is the part I'm most proud of—and the hardest to get right.

The Technical Challenge: PDF Vector Paths → PowerPoint Shapes

How PDF Stores Vector Graphics

A PDF doesn't have a concept of "icons." It has drawing operators—sequences of path commands like:

m 100 200       % moveto
l 150 250       % lineto
c 160 260 170 270 180 280  % curveto
h               % closepath
f               % fill

A single icon might be composed of dozens of these path fragments, potentially scattered across the page content stream.

Step 1: Extracting Paths with PyMuPDF

I use PyMuPDF (fitz) to extract all vector drawings from a page:

import fitz

doc = fitz.open("slides.pdf")
page = doc[0]
drawings = page.get_drawings()

for path in drawings:
    # Each path has: items (line/curve/rect commands),
    # fill color, stroke color, width, rect (bounding box)
    print(f"Path with {len(path['items'])} segments, "
          f"fill={path['fill']}, rect={path['rect']}")

A typical slide might yield 200+ individual paths. Most of them are just background rectangles or decorative lines. The challenge is figuring out which paths form an icon.

Step 2: Grouping Paths into Icons

This is where it gets interesting. My approach:

Filter out large shapes — anything spanning more than 5% of the page area is likely a background element, not an icon
Spatial clustering — paths whose bounding boxes overlap or are very close together probably belong to the same icon
Size thresholds — icons typically fall within a certain size range (16×16 to 128×128 points in PDF coordinates)

def cluster_icon_paths(paths, proximity=5.0):
    """Group nearby small paths into icon candidates."""
    clusters = []
    used = set()

    for i, p in enumerate(paths):
        if i in used or is_background(p):
            continue
        cluster = [p]
        used.add(i)
        bbox = fitz.Rect(p["rect"])

        # Find nearby paths that belong to this icon
        for j, q in enumerate(paths):
            if j in used or is_background(q):
                continue
            q_rect = fitz.Rect(q["rect"])
            if bbox.intersects(q_rect) or distance(bbox, q_rect) < proximity:
                cluster.append(q)
                used.add(j)
                bbox |= q_rect  # expand bounding box

        if len(cluster) >= 2:  # single paths are usually not icons
            clusters.append(cluster)

    return clusters

Step 3: Converting to PowerPoint Freeform Shapes

This is the final piece. PowerPoint has a FreeformBuilder API in python-pptx that lets you construct arbitrary shapes from line and curve segments:

from pptx.util import Emu

def add_icon_to_slide(slide, paths, offset_x, offset_y):
    """Convert PDF paths to a PowerPoint freeform shape."""
    builder = slide.shapes.build_freeform(
        start_x=Emu(0), start_y=Emu(0)
    )

    for path in paths:
        for item in path["items"]:
            cmd = item[0]
            if cmd == "l":  # line
                _, p1, p2 = item
                builder.add_line_segment(
                    Emu(int(p2.x - offset_x) * 12700),
                    Emu(int(p2.y - offset_y) * 12700),
                )
            elif cmd == "c":  # cubic bezier curve
                _, p1, p2, p3, p4 = item
                # python-pptx doesn't directly support cubic beziers,
                # so we approximate with line segments
                points = approximate_bezier(p1, p2, p3, p4, segments=8)
                for pt in points:
                    builder.add_line_segment(
                        Emu(int(pt.x - offset_x) * 12700),
                        Emu(int(pt.y - offset_y) * 12700),
                    )

    shape = builder.convert_to_shape()
    shape.fill.solid()
    shape.fill.fore_color.rgb = RGBColor(*paths[0]["fill"])
    return shape

The result: icons in your PowerPoint that you can resize, recolor, and edit—just like native shapes.

Architecture

┌─────────────┐     ┌──────────────────┐     ┌─────────────┐
│   Browser    │────▶│  FastAPI Backend  │────▶│  .pptx file │
│  (Next.js)   │◀────│  pymupdf + pptx   │◀────│  download   │
└─────────────┘     └──────────────────┘     └─────────────┘

Frontend: Next.js 15 (App Router) + Tailwind CSS—drag-and-drop upload with real-time progress
Backend: Python FastAPI—PDF parsing, icon extraction, PPTX generation
Auth: Google OAuth via next-auth
Payments: PayPal (pay-per-use credits)
Infra: VPS + Nginx + Cloudflare CDN + Let's Encrypt SSL

Try It / Contribute

🔗 Live demo: pdf2deck.xyz — free tier, no sign-up needed (5 pages max)

📦 GitHub: github.com/LotusWang0723/PDFtoDeck

The free tier lets you convert PDFs up to 5 pages long with no registration required. Signed-in users get 5 conversions per day. For heavier usage, credit packs start at $1.99.

What's Next

[ ] Batch conversion (upload multiple PDFs)
[ ] Better font matching (map PDF fonts to system fonts)
[ ] SVG icon detection using ML-based classification
[ ] API endpoint for programmatic access

I'd love to hear feedback—especially from anyone who's worked with PDF internals or python-pptx. The vector path grouping algorithm is still pretty naive, and I'm sure there are smarter approaches.

*If this is useful, a ⭐ on GitHub would mean a lot!*p

DEV Community: LotusWang