PPTX creation, editing, and analysis

Overview

A .pptx file is a ZIP archive containing XML files (Open XML Presentation format).

Quick Reference

Task	Approach
Read/extract content	python-pptx or unpack for raw XML
Create new presentation	pptxgenjs (JavaScript) or python-pptx
Edit existing presentation	python-pptx or unpack/edit XML/repack
Convert to images	LibreOffice headless -> PDF -> images

Reading Presentations

Extract Text with python-pptx

from pptx import Presentation

prs = Presentation("presentation.pptx")
for i, slide in enumerate(prs.slides):
    print(f"--- Slide {i+1} ---")
    for shape in slide.shapes:
        if shape.has_text_frame:
            for paragraph in shape.text_frame.paragraphs:
                print(paragraph.text)
        if shape.has_table:
            table = shape.table
            for row in table.rows:
                for cell in row.cells:
                    print(cell.text, end="\t")
                print()

Extract Metadata

prs = Presentation("presentation.pptx")
print(f"Slides: {len(prs.slides)}")
print(f"Width: {prs.slide_width}")
print(f"Height: {prs.slide_height}")

core = prs.core_properties
print(f"Title: {core.title}")
print(f"Author: {core.author}")

Creating Presentations with python-pptx

Basic Presentation

from pptx import Presentation
from pptx.util import Inches, Pt, Emu
from pptx.dml.color import RGBColor
from pptx.enum.text import PP_ALIGN

prs = Presentation()
prs.slide_width = Inches(13.333)   # Widescreen 16:9
prs.slide_height = Inches(7.5)

slide_layout = prs.slide_layouts[0]  # Title layout
slide = prs.slides.add_slide(slide_layout)
title = slide.shapes.title
subtitle = slide.placeholders[1]

title.text = "Presentation Title"
subtitle.text = "Subtitle goes here"

prs.save("output.pptx")

Adding Text Boxes

slide_layout = prs.slide_layouts[6]  # Blank layout
slide = prs.slides.add_slide(slide_layout)

txBox = slide.shapes.add_textbox(Inches(1), Inches(1), Inches(8), Inches(2))
tf = txBox.text_frame
tf.word_wrap = True

p = tf.paragraphs[0]
p.text = "First paragraph"
p.font.size = Pt(24)
p.font.bold = True
p.font.color.rgb = RGBColor(0x2E, 0x75, 0xB6)
p.alignment = PP_ALIGN.LEFT

p2 = tf.add_paragraph()
p2.text = "Second paragraph"
p2.font.size = Pt(18)
p2.space_before = Pt(12)

Adding Images

slide = prs.slides.add_slide(prs.slide_layouts[6])
slide.shapes.add_picture(
    "image.png",
    left=Inches(1), top=Inches(1.5),
    width=Inches(5), height=Inches(3.5)
)

Adding Tables

slide = prs.slides.add_slide(prs.slide_layouts[6])
rows, cols = 4, 3
table_shape = slide.shapes.add_table(
    rows, cols, Inches(1), Inches(1.5), Inches(8), Inches(3)
)
table = table_shape.table

table.columns[0].width = Inches(3)
table.columns[1].width = Inches(2.5)
table.columns[2].width = Inches(2.5)

headers = ["Name", "Role", "Department"]
for i, header in enumerate(headers):
    cell = table.cell(0, i)
    cell.text = header
    for paragraph in cell.text_frame.paragraphs:
        paragraph.font.bold = True
        paragraph.font.size = Pt(14)
        paragraph.font.color.rgb = RGBColor(0xFF, 0xFF, 0xFF)
    cell.fill.solid()
    cell.fill.fore_color.rgb = RGBColor(0x2E, 0x75, 0xB6)

data = [["Alice", "Engineer", "R&D"], ["Bob", "Designer", "UX"], ["Carol", "Manager", "Ops"]]
for row_idx, row_data in enumerate(data, start=1):
    for col_idx, value in enumerate(row_data):
        table.cell(row_idx, col_idx).text = value

Adding Charts

from pptx.chart.data import CategoryChartData
from pptx.enum.chart import XL_CHART_TYPE

slide = prs.slides.add_slide(prs.slide_layouts[6])
chart_data = CategoryChartData()
chart_data.categories = ['Q1', 'Q2', 'Q3', 'Q4']
chart_data.add_series('Revenue', (120, 135, 148, 162))
chart_data.add_series('Expenses', (95, 102, 108, 115))

chart = slide.shapes.add_chart(
    XL_CHART_TYPE.COLUMN_CLUSTERED,
    Inches(1), Inches(1.5), Inches(8), Inches(5),
    chart_data
).chart
chart.has_legend = True

Creating with pptxgenjs (JavaScript)

const pptxgen = require("pptxgenjs");
const pres = new pptxgen();
pres.layout = "LAYOUT_WIDE";

let slide = pres.addSlide();
slide.addText("Title", {
    x: 0.5, y: 2, w: 12, h: 1.5,
    fontSize: 36, bold: true, color: "2E75B6", align: "center"
});

slide = pres.addSlide();
slide.addText([
    { text: "Point 1", options: { bullet: true, fontSize: 18 } },
    { text: "Point 2", options: { bullet: true, fontSize: 18 } },
], { x: 0.5, y: 1.5, w: 11, h: 4 });

pres.writeFile({ fileName: "output.pptx" });

Editing Existing Presentations

from pptx import Presentation

prs = Presentation("existing.pptx")
slide = prs.slides[0]
if slide.shapes.title:
    slide.shapes.title.text = "Updated Title"
prs.save("modified.pptx")

Converting to Images

python scripts/office/soffice.py --headless --convert-to pdf presentation.pptx
pdftoppm -jpeg -r 150 presentation.pdf slide

Design Best Practices

• Consistent fonts: Arial/Calibri for body; limit to 2-3 fonts
• Color palette: primary + 2-3 complementary colors
• 16:9 widescreen (13.333 x 7.5 inches) is standard
• One main idea per slide
• High-quality images (min 150 DPI)
• Title: 28-36pt; body: 18-24pt; minimum 14pt

Dependencies

• python-pptx: pip install python-pptx
• pptxgenjs: npm install pptxgenjs
• LibreOffice: PDF/image conversion
• Poppler: pdftoppm for PDF to images