Feature Walkthrough Video Generation

Feature Walkthrough Video Generation

Generate polished demo videos from Playwright test suites. Perfect for showcasing features, onboarding flows, or creating documentation videos.

Prerequisites

Required tools:

• Playwright - Test runner with video recording
• ffmpeg - Video processing and concatenation
• ImageMagick - Title card generation

# Verify prerequisites
which ffmpeg && which convert && npx playwright --version

Working Directory

All artifacts stored in /​tmp/​walkthrough/​{session-id}/:

/​tmp/​walkthrough/​{session-id}/
  config.json                    # Session configuration
  playwright-video.config.ts     # Generated Playwright config
  recordings/                    # Raw Playwright video output
  build/                         # Intermediate files (title cards, slowed clips)
  {output-name}.mp4              # Final video (copied to user's output dir)

This location preserves context between sessions and avoids accidental commits.

Playwright Video Config

Enable recording with sequential execution:

import { defineConfig, devices } from '@playwright/​test'

export default defineConfig({
  fullyParallel: false,  // Sequential for predictable ordering
  retries: 0,            // No retries - clean recordings
  workers: 1,            // Single worker for consistent capture
  reporter: [['list']],
  use: {
    video: 'on',         // Always record
    trace: 'off',        // Reduce overhead
  },
  projects: [
    { name: 'chromium', use: { ...devices['Desktop Chrome'] } },
  ],
  outputDir: '/​tmp/​walkthrough/​{session-id}/​recordings/',
  timeout: 120 * 1000,   // Generous timeout for recording
})

Configuration Options

ffmpeg Reference

Get video dimensions:

ffprobe -v error -select_streams v:0 -show_entries stream=width,height -of csv=p=0 video.webm

WebM to MP4:

ffmpeg -i video.webm -c:v libx264 -c:a aac -y video.mp4 2>/​dev/​null

Title card image to video (3 seconds):

ffmpeg -loop 1 -i title.png -c:v libx264 -t 3 -pix_fmt yuv420p -r 30 title.mp4 -y 2>/​dev/​null

Slow down video (10x):

ffmpeg -i input.mp4 -filter:v "setpts=10*PTS" -r 30 slowed.mp4 -y 2>/​dev/​null

Concatenate clips:

# Create concat_list.txt:
# file 'title_main.mp4'
# file 'title_01.mp4'
# file 'slow_01.mp4'
# ...

ffmpeg -f concat -safe 0 -i concat_list.txt -c:v libx264 -preset medium -crf 23 output.mp4 -y

ImageMagick Title Cards

Main title card:

convert -size {WIDTH}x{HEIGHT} xc:'#1e293b' \
  -font DejaVu-Sans-Bold -pointsize 48 -fill white -gravity center \
  -annotate +0-20 "{MAIN_TITLE}" \
  -font DejaVu-Sans -pointsize 20 -fill '#94a3b8' \
  -annotate +0+40 "{SUBTITLE}" \
  title_main.png

Section title card:

convert -size {WIDTH}x{HEIGHT} xc:'#1e293b' \
  -font DejaVu-Sans-Bold -pointsize 36 -fill white -gravity center \
  -annotate +0-30 "{SECTION_TITLE}" \
  -font DejaVu-Sans -pointsize 20 -fill '#94a3b8' \
  -annotate +0+30 "{SECTION_SUBTITLE}" \
  title_01.png

Test Selection

By spec file:

npx playwright test tests/​integration/​onboarding.spec.ts --config=...

By grep pattern:

npx playwright test --grep "checkout" --config=...

List available tests first:

npx playwright test --list --grep "{pattern}"

Title Generation

Auto-generate from test names:

• should complete checkout flow -> "Complete Checkout Flow"
• displays validation errors on empty form -> "Form Validation Errors"

User can override with custom titles per test.

Error Handling

Test failures: Still process the video - shows what happened. Report which tests failed.

Missing videos: Skip tests without recordings. Continue with available clips.

Font issues: Fall back to default fonts. Warn about substitution.

Quality Checklist

• All selected tests ran
• All video files converted successfully
• Title cards match video dimensions
• Final video plays without errors
• Output copied to user's specified directory