FRAME 00000 • 00:00:00 • NTSC • LINE 240/525
🔌 COMPOSITE (CVBS) — Yellow RCA
▶ SHOW SIGNAL REFERENCE
◈ NTSC (525-line, 59.94 Hz)
Used in North America, Japan, parts of South America.
- Subcarrier: 3.579545 MHz
- QAM encoding: I & Q channels
- Phase-sensitive — hue can shift ("Never The Same Color")
- Colorburst: ~8–10 cycles of inverted subcarrier reference
◈ PAL (625-line, 50 Hz)
Used in most of Europe, Australia, parts of Asia & Africa.
- Subcarrier: 4.43361875 MHz
- Phase Alternating Line — V-component inverted every other line
- Cancels phase errors automatically (no tint control needed)
- Better color accuracy than NTSC, slightly lower vertical resolution perception at 50 Hz
◈ SECAM (625-line, 50 Hz)
Used in France, Russia, parts of Africa & Middle East.
- FM-encoded chroma — Db at 4.25 MHz, Dr at 4.406 MHz
- Color transmitted sequentially, one component per line
- No colorburst — phase is irrelevant
- "SECAM fire" artifacts on sharp color transitions
◈ CROSS-COLOR ARTIFACTS
Because luma and chroma share bandwidth:
- Cross-Color: High-freq luma → false color (rainbow on stripes)
- Cross-Luminance: Chroma → visible dot crawl pattern
- S-Video eliminates these by keeping Y/C separate
- Comb filters reduce artifacts by comparing adjacent lines
◈ VHS & RECORDING FORMATS
Different recording formats degrade the signal in unique ways:
- VHS: Color-under at ~629 kHz, ~3 MHz luma BW, ~500 kHz chroma
- LaserDisc: True composite on FM carrier, higher quality
- U-matic: Professional color-under, better than VHS
- D-2: Digital composite at 4fsc sampling
◈ CONNECTORS
Composite video uses various physical connections:
- RCA (yellow): Consumer standard, 75Ω unbalanced
- BNC: Professional broadcast, bayonet lock
- DIN: European home computers (C64, etc.)
- Cable: 75Ω coaxial, 52–69 pF/m capacitance