RampForge

Turn marker points into polished speed ramps automatically.

RampForge is a personal video editing tool that automatically generates smooth speed ramp effects from user-defined markers and curve presets. It is built for creators who want cinematic motion changes without manually keyframing speed graphs in complex editors. The product calculates the ramp curve, applies optional zoom presets, and renders a finished video in a few clicks.

Business Goals

  • Reach 5,000 monthly active users within 6 months of launch.
  • Convert at least 12% of free users to paid plans within 90 days of first use.
  • Keep monthly churn below 6% among paid subscribers after month 3.
  • Reduce average time from upload to exported video to under 8 minutes for 1080p clips by the end of Q2.
  • Achieve a 25% week-4 retention rate for first-time users.

User Goals

  • Create a smooth speed ramp without manually animating keyframes.
  • Apply a consistent zoom preset that matches the ramp timing.
  • Preview the final effect before rendering the export.
  • Produce a shareable or downloadable edited video in one workflow.
  • Save favorite marker and curve presets for repeated use.

Non-Goals

  • Full multi-track nonlinear video editing is out of scope for MVP.
  • AI-generated scene selection or automatic cinematic direction is out of scope.
  • Collaboration, comments, and shared project workspaces are out of scope initially.
  • Advanced color grading, sound design, and compositing tools are out of scope.

Creator Dimas, 27 - A short-form content creator who edits action clips for TikTok, Instagram Reels, and YouTube Shorts. He wants a fast way to make movement feel cinematic without spending time in pro editors.

Creator Dimas, 27

  • As a creator, I want to drop in markers at key moments, so that the speed change happens exactly where the action peaks.
  • As a creator, I want to choose a preset ramp curve, so that I can get a professional look without tuning keyframes manually.
  • As a creator, I want to preview the motion before export, so that I can catch awkward transitions early.

Social Media Manager Rina, 34 - A marketer who needs to produce branded vertical videos quickly for campaigns and product launches. She values repeatable presets, consistency, and simple exports.

Social Media Manager Rina, 34

  • As a social media manager, I want to reuse saved ramp and zoom presets, so that every campaign video has a consistent style.
  • As a social media manager, I want to export in platform-friendly aspect ratios, so that I can publish without reformatting in another tool.
  • As a social media manager, I want the tool to warn me about unsupported clips or bad marker placement, so that I avoid failed renders.

Motion Hobbyist Arif, 22 - An enthusiast experimenting with cinematic edits from phone footage and action camera clips. He cares about creative control, but not about learning complex pro software.

Motion Hobbyist Arif, 22

  • As a hobbyist, I want to see how the curve affects timing, so that I can learn what looks best for my footage.
  • As a hobbyist, I want to adjust zoom intensity independently from speed, so that I can create a more dramatic effect.
  • As a hobbyist, I want to render locally or in the cloud depending on file size, so that I can finish edits on different devices.

Marker-Based Ramp Creation · High priority

  • Users can define the start, peak, and end points of a speed ramp using timeline markers, and the system converts those markers into a continuous speed curve.
  • Support at least three marker types: ramp start, slow-motion peak, and ramp end.
  • Validate that markers are in chronological order and show inline errors if they overlap or are too close.
  • Allow users to drag markers on a timeline with frame-level snapping.
  • Persist marker positions per project so users can reopen and refine them later.

Preset Curve Engine · High priority

  • Users choose from predefined speed curve presets and the system computes the interpolation logic automatically.
  • Provide at least four presets: cinematic, aggressive, subtle, and punch-in.
  • Map each preset to a configurable speed profile with min/max speed limits.
  • Display a visual curve preview before rendering.
  • Allow users to save custom presets with a name, curve shape, and default zoom style.

Zoom Presets and Motion Sync · High priority

  • The app applies zoom movements that stay synchronized with the speed ramp for a cohesive cinematic result.
  • Offer preset zoom behaviors such as no zoom, gentle push, and dramatic punch-in.
  • Tie zoom timing to ramp markers by default, with optional independent adjustment.
  • Limit zoom to safe bounds to avoid crop artifacts.
  • Warn when the chosen zoom preset may cut off subject framing on portrait clips.

Preview and Render Pipeline · High priority

  • Users can preview the effect and render a final output video with a reliable processing workflow.
  • Generate a low-resolution preview within 30 seconds for clips under 60 seconds.
  • Render final exports in H.264 MP4 by default, with optional H.265 where supported.
  • Show render progress, estimated completion time, and retry options on failure.
  • Preserve original audio timing unless the user explicitly opts into audio time-stretching.

Project Management and Export · Medium priority

  • Users can organize, reuse, and export projects in a lightweight personal workflow.
  • Let users create, duplicate, rename, and delete projects.
  • Store project metadata, source clip references, markers, preset selections, and export history.
  • Support exporting to local download and cloud share link.
  • Keep a simple activity log of edits and render attempts.

First-Time User Experience

  • Sign up with email, Google, or Apple.
  • Upload or import a short video clip from device storage or cloud storage.
  • Choose an aspect ratio and a ramp preset.
  • Place markers on the timeline and see the curve auto-generate immediately.
  • Preview the effect and render a sample export.
  • Reach a first successful render in under 5 minutes for a 30 to 60 second clip.

1. Import Clip

  • The user starts by uploading a source video and selecting a project format. The app prepares metadata, duration, and a scrubber timeline.
  • Accept MP4, MOV, and common phone camera formats.
  • Reject corrupted or unsupported files with a clear recovery message.
  • Show clip duration, frame rate, and aspect ratio after import.

2. Place Markers

  • The user sets ramp start, peak, and end markers on the timeline. The system snaps markers to frames and validates spacing.
  • Prevent markers from being placed outside clip bounds.
  • Show a warning when marker spacing is too tight for a smooth ramp.
  • Allow keyboard nudging for precise adjustments.

3. Select Preset

  • The user chooses a speed curve preset and an optional zoom preset. The app updates the curve visualization instantly.
  • Display a before/after preview of the selected preset.
  • Let users compare presets without losing marker positions.
  • Show the resulting min and max speeds in plain language.

4. Preview Motion

  • The user scrubs through a rendered preview to confirm timing and framing. The app generates a lightweight preview quickly before full export.
  • Render a proxy preview at lower resolution first.
  • Highlight any sections where zoom framing may clip the subject.
  • Pause preview generation if the user makes a new edit.

5. Render and Export

  • The user exports the finished video to the device or a shareable link. The app renders the final file and tracks status until completion.
  • Show progress percentage, estimated remaining time, and error states.
  • Retry failed renders from the last valid checkpoint when possible.
  • Allow users to rename the output before download.

Advanced Features

  • Custom curve editor for users who want to fine-tune acceleration and deceleration points.
  • Batch processing for applying one preset to multiple clips.
  • Project templates for recurring styles such as sports, travel, and product demos.
  • Smart zoom safety guide that detects likely subject cutoffs on vertical video.
  • Cloud rendering fallback for large files or low-powered devices.

UI and Interaction Principles

  • Timeline must be visually clear, with distinct marker colors and curve overlays.
  • Preview should update responsively without forcing full re-render on every small change.
  • Use large touch targets and keyboard shortcuts for marker placement and timeline scrubbing.
  • Provide strong contrast and readable labels for users editing on laptops and phones.
  • Show deterministic progress states so users understand whether the app is analyzing, previewing, or rendering.

Dimas has a 45-second skate clip with a great landing moment, but in his usual editor the speed ramp takes too long to build. He uploads the clip into RampForge, drops three markers around the trick, picks the cinematic preset, and immediately sees the curve and zoom preview update on the timeline.

He notices the zoom is too tight near the landing, so he switches to a gentler preset and replays the preview. The final render finishes in minutes, and he exports a polished clip that looks professionally timed without wrestling with keyframes.

For Dimas, the win is speed and consistency. For the product, the win is repeat usage: once he trusts the workflow, every action clip becomes a fast, repeatable session instead of a frustrating edit.},

User-Centric Metrics

  • At least 80% of first-time users complete one render within 5 minutes.
  • Preview satisfaction rating of 4.5 out of 5 or higher.
  • Less than 10% of projects require marker rework after preview.
  • Average number of renders per active user reaches 3 per month within 90 days.
  • At least 35% of users save or reuse a preset within two weeks.

Business Metrics

  • Free-to-paid conversion reaches 12% within 90 days.
  • Monthly active users grow to 5,000 within 6 months.
  • Paid churn remains below 6% monthly after the third billing cycle.
  • Referral or organic sharing drives 20% of new signups by month 6.

Technical Metrics

  • 99.5% monthly uptime for the web app and render service.
  • Preview generation p95 under 30 seconds for clips under 60 seconds.
  • Final render p95 under 10 minutes for 1080p clips up to 2 minutes.
  • Zero known data loss incidents from project save or export workflows.

Tracking Plan

  • Track signup_completed with source and auth provider.
  • Track clip_uploaded with file duration, format, and size.
  • Track markers_added with marker count and spacing validity.
  • Track preset_selected with preset name and zoom style.
  • Track preview_generated with render time and success or failure.
  • Track export_started and export_completed with output format and duration.
  • Track preset_saved to measure repeatability and retention.

Technical Needs

  • Frontend in Next.js with React for a fast browser-based editing experience.
  • Timeline and waveform/curve visualization using Canvas or WebGL for responsive interaction.
  • Backend API in Node.js or TypeScript for project orchestration and preset logic.
  • Render workers using FFmpeg for speed remapping, zoom transforms, and output encoding.
  • Job queue with Redis and BullMQ or a managed queue for reliable asynchronous rendering.
  • Object storage such as AWS S3 or Cloudflare R2 for source and output media.
  • Database such as Postgres for projects, markers, presets, and render history.

Integration Points

  • Google OAuth and Apple Sign-In for authentication.
  • Stripe for subscriptions and usage-based billing.
  • Cloud storage imports from Google Drive and Dropbox.
  • S3-compatible storage for uploads and rendered exports.
  • Optional email notifications through SendGrid or Postmark for render completion.

Data Storage & Privacy

  • Store only the minimum video metadata required for processing unless the user opts into cloud persistence.
  • Encrypt media at rest and in transit with TLS 1.2+ and server-side encryption on object storage.
  • Provide delete project and delete account flows that remove associated media and metadata.
  • Support GDPR and CCPA requests for export, deletion, and disclosure of personal data.
  • Set retention limits for temporary preview files and failed render artifacts, such as automatic cleanup after 7 days.

Scalability & Performance

  • Use asynchronous job processing so rendering load does not block the user interface.
  • Cache preset calculations and render parameters to avoid recomputing the same curve repeatedly.
  • Separate preview renders from final exports to protect final render throughput.
  • Scale worker pool horizontally based on queue depth and average render time.

Potential Challenges

  • Frame-accurate speed ramps can drift across codecs; mitigate by normalizing timestamps and validating with FFmpeg probes.
  • Zoom can crop important content on vertical clips; mitigate with framing safety checks and visible warnings.
  • Large uploads may fail on unstable connections; mitigate with resumable uploads and chunked transfer support.
  • Rendering costs can rise quickly with heavy usage; mitigate with job limits, tiered pricing, and preview compression.
  • Users may expect perfect audio handling; mitigate by clearly labeling audio behavior and offering optional time-stretching in later phases.

Team & resourcing - Small team - 2 engineers, 1 product designer, part-time PM, and shared QA/support.

Phase 1: MVP Workflow · Weeks 1-4

  • Authentication and project creation
  • Video upload and clip metadata extraction
  • Marker placement on a basic timeline
  • Preset curve selection with visual preview
  • Single-output MP4 render pipeline with download

Phase 2: Preview and Presets · Weeks 5-8

  • Low-resolution preview rendering
  • Zoom preset system synchronized with ramp markers
  • Saved custom presets and project duplication
  • Render progress UI and retry handling
  • Basic analytics instrumentation

Phase 3: Reliability and Monetization · Weeks 9-12

  • Stripe subscriptions and feature gating
  • Cloud rendering fallback for large jobs
  • Improved validation and error messaging
  • Account deletion and data export flows
  • Performance optimization for uploads and renders

Phase 4: Growth Features · Weeks 13-16

  • Batch processing
  • Project templates for common creator workflows
  • Cloud import integrations
  • Refined keyboard shortcuts and accessibility improvements
  • Usage dashboards for retention and conversion monitoring

Paste this into Cursor, Bolt, Lovable, or v0 to start building.

Build a web app called RampForge that automatically creates smooth video speed ramps from user-defined markers and preset curves.

Core product:
Users upload a short video, place ramp markers on a timeline, choose a speed curve preset, optionally apply a zoom preset, preview the result, and render/export the final MP4.

Build these screens and flows:
1) Auth and onboarding with Google, Apple, and email login
2) Dashboard with recent projects and create-new-project button
3) Project editor with video player, scrubber timeline, draggable markers, curve preview, preset picker, zoom preset picker, and render controls
4) Preview generation state with progress and retry
5) Export history and project settings
6) Billing screen for Stripe subscription management

Data model:
User(id, email, name, authProvider, plan, createdAt)
Project(id, userId, name, sourceVideoUrl, aspectRatio, duration, status, createdAt, updatedAt)
Marker(id, projectId, type, timeMs, order)
Preset(id, userId nullable, name, speedCurveJson, zoomStyle, isSystemDefault)
RenderJob(id, projectId, mode preview or final, status, progress, outputUrl, errorMessage, createdAt)
ExportHistory(id, projectId, fileName, format, duration, outputUrl, createdAt)

Functional requirements:
- Upload MP4, MOV, and common mobile video formats
- Extract duration, framerate, and aspect ratio from the source clip
- Validate marker ordering and spacing
- Auto-generate a smooth speed curve from marker points
- Apply synchronized zoom presets
- Render low-res previews quickly and final exports asynchronously using FFmpeg
- Support save, duplicate, rename, and delete project actions
- Track analytics events for upload, marker placement, preset selection, preview generation, and export completion

Recommended stack:
Next.js 14, React, TypeScript, Tailwind CSS, shadcn/ui, Framer Motion for interactions, Canvas or WebGL for timeline visualization, Node.js backend with NestJS or Express, Postgres, Redis + BullMQ, AWS S3 or Cloudflare R2, FFmpeg workers, Stripe, Google/Apple OAuth, SendGrid or Postmark, and deployment on Vercel for frontend plus Dockerized workers on AWS ECS or Fly.io.

Implementation notes:
- Make the editor feel fast and responsive with local state updates and debounced server sync
- Use a job queue for all preview and final renders
- Store projects and presets in Postgres and media in object storage
- Include loading, error, empty, and unsupported-file states
- Design for mobile and desktop responsive layouts
- Add keyboard shortcuts for timeline scrubbing and marker nudging
- Include accessibility support with high contrast, focus states, and ARIA labels

Business Idea

Proyek ini membangun alat bantu pribadi yang membuat speed ramp (perubahan kecepatan video yang halus, misalnya normal → slow-motion → normal) secara otomatis. Pengguna cukup menentukan titik marker dan memilih preset kurva; alat menghitung kurva kecepatan; memilih preset zoom dan merender video hasil.

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