videobeaux/docs/programs/effects/ball_point_pen.md

ball_point_pen

Description

Applies a ball-point-pen illustration effect to the input video, simulating hand-drawn line textures, monochrome ink shading, and stylized pen-stroke contrast.
The result evokes sketchbook drawings, technical notebook diagrams, or lo-fi comic-style renderings.

Purpose

ball_point_pen is intended for artists who want to:

• transform footage into a drawn, pen-sketched look,
• reduce photographic realism while retaining motion,
• create stylized rotoscope-like results,
• mimic ink illustrations or doodle-style animation,
• apply a minimalistic or DIY illustration aesthetic.

How It Works

1. Edge Extraction
   The effect identifies major contours and turns them into pen-like strokes.
2. Ink Shading Simulation
   Midtones and shadows are reinterpreted as sparse or dense ink hatching.
3. Monochrome / Limited Palette Rendering
   The image is reduced to a pen-like tonal range, often high-contrast and desaturated.
4. Encoding
   The processed frames are written using global Videobeaux output settings (codec, CRF, pixel format).

Program Template

videobeaux -P ball_point_pen \
  -i input.mp4 \
  -o output.mp4

Arguments

• (No additional program-specific arguments; uses global videobeaux options only.)

Real World Example

videobeaux -P ball_point_pen \
  -i myvideo.mp4 \
  -o ball_point_pen_styled.mp4

Program Output

Technical Notes

• The final aesthetic depends on global pixel format and compression parameters.
• Works especially well on footage with strong edges, clean lighting, or high motion.
• Since the process reduces tonal detail, compression artifacts may become more noticeable — sometimes adding to the hand-drawn look.
• Best results may come from source footage with minimal noise.

Recommended Usage

• Rotoscope-style animation sequences.
• Comic-inspired music videos or narrative interludes.
• Experimental art filtering where realism is intentionally minimized.
• Educational or technical visualization with a “diagram” aesthetic.
• Mixed-media projects combining live-action with hand-drawn elements.

Quality Tips

• Consider pairing with convert_dims (square formats like 1080×1080) for Instagram-style sketch loops.
• Use a lower CRF (higher quality) to preserve line fidelity.
• Pair with gamma_fix or lut_apply before applying the pen effect for clearer edges.
• Apply final sharpening or embossing in a later step if you want more aggressive pen stroke definition.
• Rotoscoped motion reads best when frame rate is preserved — avoid additional frame dropping unless stylistically intentional.