HDMI vs DisplayPort vs SDI: Video Connection Guide
Choosing the right video connection for your digital signage installation impacts reliability, image quality, cable runs, and future scalability. This guide compares all major video interfaces to help you select the best option for your deployment.
Quick Comparison
| Feature | HDMI 2.1 | DisplayPort 2.1 | SDI (12G) | HDBaseT | AV-over-IP |
|---|
| Max Resolution | 10K | 16K | 4K | 4K | 8K+ |
| Max Cable Length | 15m (passive) | 15m (passive) | 100m+ | 100m | Unlimited |
| Audio Support | Yes | Yes | Embedded | Yes | Yes |
| Daisy Chain | No | Yes (MST) | No | No | N/A |
| Locking Connector | No | Yes | Yes (BNC) | Yes | N/A |
| Cost | Low | Low | Medium | Medium | High |
| Best For | General use | High-res, video walls | Broadcast, pro AV | Long runs | Enterprise |
Overview
HDMI is the most common video connection in digital signage due to its ubiquity, ease of use, and support across virtually all displays and media players.
┌─────────────────────────────────────────────────────────────────────┐
│ HDMI SPECIFICATIONS │
├─────────────────────────────────────────────────────────────────────┤
│ │
│ VERSION COMPARISON │
│ │
│ │ Version │ Max Res @ 60Hz │ Bandwidth │ HDR │ Key Feature │
│ ├─────────┼────────────────┼────────────┼──────┼───────────────────│
│ │ 1.4 │ 4K @ 30Hz │ 10.2 Gbps │ No │ 3D support │
│ │ 2.0 │ 4K @ 60Hz │ 18 Gbps │ Yes │ 4K standard │
│ │ 2.0b │ 4K @ 60Hz │ 18 Gbps │ Yes │ HDR10, HLG │
│ │ 2.1 │ 8K @ 60Hz │ 48 Gbps │ Yes │ 10K, VRR, eARC │
│ │
│ CONNECTOR TYPES │
│ │
│ Type A (Standard): 19-pin, most common │
│ Type C (Mini): Smaller devices │
│ Type D (Micro): Mobile devices │
│ │
│ CABLE LENGTH GUIDELINES │
│ │
│ │ Resolution │ Passive Cable │ Active Cable │ Fiber HDMI │ │
│ ├──────────────┼───────────────┼───────────────┼────────────│ │
│ │ 1080p │ Up to 15m │ Up to 30m │ 100m+ │ │
│ │ 4K @ 60Hz │ Up to 5m │ Up to 15m │ 100m+ │ │
│ │ 8K @ 60Hz │ Up to 3m │ Up to 10m │ 100m+ │ │
│ │
└─────────────────────────────────────────────────────────────────────┘
Pros & Cons for Digital Signage
| Pros | Cons |
|---|
| Universal compatibility | No locking connector |
| Low cost | Limited cable length |
| Audio + video in one cable | HDCP can cause issues |
| CEC control support | No daisy chain |
| Widely available | Connector can work loose |
When to Use HDMI
- Standard installations with cable runs under 15m
- Budget-conscious deployments
- Single displays (not video walls requiring daisy chain)
- Consumer-grade displays that only have HDMI inputs
HDMI Tips for Digital Signage
- Use certified cables - Avoid cheap cables for 4K; look for "Premium High Speed" certification
- Secure connections - Use HDMI locks or cable ties to prevent disconnection
- Consider active cables - For runs over 7m at 4K
- HDCP compliance - Ensure all devices in chain support same HDCP version
- CEC control - Enable for remote power control of displays
DisplayPort
Overview
DisplayPort is often superior to HDMI for professional applications, offering higher bandwidth, daisy chaining, and locking connectors.
┌─────────────────────────────────────────────────────────────────────┐
│ DISPLAYPORT SPECIFICATIONS │
├─────────────────────────────────────────────────────────────────────┤
│ │
│ VERSION COMPARISON │
│ │
│ │ Version │ Max Res @ 60Hz │ Bandwidth │ Key Feature │
│ ├─────────┼────────────────┼────────────┼──────────────────────────│
│ │ 1.2 │ 4K @ 60Hz │ 21.6 Gbps │ MST (daisy chain) │
│ │ 1.4 │ 8K @ 30Hz │ 32.4 Gbps │ HDR, DSC compression │
│ │ 2.0 │ 16K @ 60Hz │ 80 Gbps │ Full 8K uncompressed │
│ │ 2.1 │ 16K @ 60Hz │ 80 Gbps │ Improved cable specs │
│ │
│ MST (Multi-Stream Transport) DAISY CHAIN │
│ │
│ ┌─────────┐ ┌─────────┐ ┌─────────┐ ┌─────────┐ │
│ │ Media │───►│Display 1│───►│Display 2│───►│Display 3│ │
│ │ Player │ DP │ DP In │ DP │ DP In │ DP │ DP In │ │
│ └─────────┘ │ DP Out │───►│ DP Out │───►│ (End) │ │
│ └─────────┘ └─────────┘ └─────────┘ │
│ │
│ MST Resolution Limits (Total bandwidth shared): │
│ • 2 displays: 2x 4K @ 60Hz │
│ • 3 displays: 3x 2560x1440 @ 60Hz │
│ • 4 displays: 4x 1920x1080 @ 60Hz │
│ │
│ CONNECTOR TYPES │
│ │
│ Standard DisplayPort: 20-pin, locking mechanism │
│ Mini DisplayPort: Compact version (Thunderbolt compatible) │
│ USB-C (Alt Mode): DisplayPort over USB-C connector │
│ │
└─────────────────────────────────────────────────────────────────────┘
Pros & Cons for Digital Signage
| Pros | Cons |
|---|
| Locking connector | Less common on displays |
| Daisy chain (MST) | Consumer TVs rarely have DP |
| Higher bandwidth than HDMI | Cable length still limited |
| Royalty-free | Less universal than HDMI |
| Better for high refresh rates | May need adapters |
When to Use DisplayPort
- Video walls using MST daisy chain
- High-resolution displays (8K, high refresh rate)
- Commercial displays with DP inputs
- PC-based media players with DP outputs
- When locking connectors are required for reliability
SDI (Serial Digital Interface)
Overview
SDI is the professional broadcast standard, offering long cable runs, locking connectors, and robust reliability for mission-critical applications.
┌─────────────────────────────────────────────────────────────────────┐
│ SDI SPECIFICATIONS │
├─────────────────────────────────────────────────────────────────────┤
│ │
│ SDI STANDARDS │
│ │
│ │ Standard │ Bandwidth │ Max Resolution │ Cable Length │
│ ├──────────┼───────────┼────────────────┼──────────────────────────│
│ │ SD-SDI │ 270 Mbps │ 480i/576i │ 300m │
│ │ HD-SDI │ 1.5 Gbps │ 1080i/720p │ 100m │
│ │ 3G-SDI │ 3 Gbps │ 1080p60 │ 100m │
│ │ 6G-SDI │ 6 Gbps │ 2160p30 (4K) │ 50m │
│ │ 12G-SDI │ 12 Gbps │ 2160p60 (4K) │ 50m (high-quality cable)│
│ │
│ CONNECTOR: BNC (Bayonet Neill-Concelman) │
│ │
│ ╭───╮ │
│ ┌──│ │──┐ • Twist-lock mechanism │
│ │ ╰───╯ │ • Extremely secure connection │
│ │ (BNC) │ • Industry standard in broadcast │
│ └─────────┘ • 75-ohm coaxial cable │
│ │
│ SDI CABLE TYPES │
│ │
│ RG-6: Consumer grade, shorter runs │
│ RG-59: Standard broadcast, up to 100m for HD │
│ Belden 1694A: Premium, recommended for 3G-SDI │
│ Belden 4694R: 12G-SDI rated, low-loss │
│ │
└─────────────────────────────────────────────────────────────────────┘
Pros & Cons for Digital Signage
| Pros | Cons |
|---|
| Very long cable runs (100m+) | Max 4K resolution (12G) |
| Locking BNC connectors | Requires converters for HDMI displays |
| Broadcast-grade reliability | Higher cable cost |
| No HDCP issues | Not on consumer displays |
| Embedded audio | Specialized equipment needed |
When to Use SDI
- Long cable runs where HDMI/DP won't reach
- Broadcast environments (TV studios, control rooms)
- Mission-critical installations requiring maximum reliability
- Outdoor LED walls (many accept SDI directly)
- Integration with broadcast equipment
HDBaseT
Overview
HDBaseT transmits video, audio, power, and control signals over standard Cat6 ethernet cable for runs up to 100m.
┌─────────────────────────────────────────────────────────────────────┐
│ HDBaseT SPECIFICATIONS │
├─────────────────────────────────────────────────────────────────────┤
│ │
│ THE 5PLAY FEATURE SET │
│ │
│ HDBaseT transmits 5 signals over a single Cat6 cable: │
│ │
│ 1. VIDEO: Up to 4K @ 60Hz (with HDBaseT 2.0) │
│ 2. AUDIO: Multi-channel, uncompressed │
│ 3. ETHERNET: 100Mbps data connection │
│ 4. CONTROL: RS-232, IR passthrough │
│ 5. POWER: Up to 100W PoH (Power over HDBaseT) │
│ │
│ │
│ SYSTEM ARCHITECTURE │
│ │
│ ┌─────────┐ ┌──────────────┐ Cat6 ┌──────────────┐ │
│ │ Media │───►│ HDBaseT │═══════════►│ HDBaseT │ │
│ │ Player │HDMI│ Transmitter │ (100m) │ Receiver │ │
│ └─────────┘ └──────────────┘ └──────┬───────┘ │
│ │ HDMI │
│ ┌──────▼───────┐ │
│ │ Display │ │
│ └──────────────┘ │
│ │
│ HDBASET VERSIONS │
│ │
│ │ Version │ Bandwidth │ Max Resolution │ Distance │
│ ├──────────┼───────────┼────────────────┼─────────────────────────│
│ │ 1.0 │ 10.2 Gbps │ 4K @ 30Hz │ 100m │
│ │ 2.0 │ 18 Gbps │ 4K @ 60Hz │ 100m │
│ │ 3.0 │ 48 Gbps │ 8K @ 60Hz │ 100m (uncompressed) │
│ │
│ CABLE REQUIREMENTS │
│ │
│ Minimum: Cat5e (shorter runs, 1080p) │
│ Recommended: Cat6 (full spec, up to 100m) │
│ Best: Cat6A (guaranteed 4K performance) │
│ │
│ Important: Use SOLID CORE cable, not stranded │
│ │
└─────────────────────────────────────────────────────────────────────┘
Pros & Cons for Digital Signage
| Pros | Cons |
|---|
| 100m over standard Cat6 | Requires TX/RX equipment |
| Single cable for video + control | Added cost per endpoint |
| Uses existing cable infrastructure | Point-to-point only |
| Power over cable (PoH) | Latency slightly higher than direct |
| Locking RJ45 option | Not as common as HDMI |
When to Use HDBaseT
- Runs between 15-100m where HDMI won't reach
- Retrofits using existing Cat6 infrastructure
- Centralized equipment rooms with remote displays
- Installations requiring RS-232 control over distance
- Displays without local power (using PoH)
AV-over-IP
Overview
AV-over-IP distributes video over standard IP networks, enabling unlimited scalability and flexibility for enterprise deployments.
┌─────────────────────────────────────────────────────────────────────┐
│ AV-OVER-IP ARCHITECTURE │
├─────────────────────────────────────────────────────────────────────┤
│ │
│ NETWORK-BASED VIDEO DISTRIBUTION │
│ │
│ ┌─────────┐ ┌──────────────┐ │
│ │ Source 1│───►│ Encoder │──┐ │
│ └─────────┘ └──────────────┘ │ │
│ │ ┌─────────────────┐ │
│ ┌─────────┐ ┌──────────────┐ │ │ │ │
│ │ Source 2│───►│ Encoder │──┼─────►│ Network Switch │ │
│ └─────────┘ └──────────────┘ │ │ (10GbE/25GbE) │ │
│ │ │ │ │
│ ┌─────────┐ ┌──────────────┐ │ └────────┬────────┘ │
│ │ Source 3│───►│ Encoder │──┘ │ │
│ └─────────┘ └──────────────┘ │ │
│ │ │
│ ┌───────────────────────────────────┼────────┐ │
│ │ │ │ │
│ ▼ ▼ ▼ │
│ ┌──────────────┐ ┌──────────────┐ │
│ │ Decoder │ │ Decoder │ ... │
│ └──────┬───────┘ └──────┬───────┘ │
│ │ │ │
│ ┌──────▼───────┐ ┌──────▼───────┐ │
│ │ Display │ │ Display │ │
│ └──────────────┘ └──────────────┘ │
│ │
│ COMMON PROTOCOLS │
│ │
│ │ Protocol │ Compression │ Latency │ Bandwidth Required │
│ ├────────────┼─────────────┼────────────┼─────────────────────────│
│ │ NDI │ Moderate │ 2-3 frames │ ~150 Mbps (1080p60) │
│ │ SDVoE │ None │ <1 frame │ 10 Gbps (4K60) │
│ │ SMPTE 2110 │ None │ <1 frame │ 12+ Gbps (4K60) │
│ │ Dante AV │ Moderate │ 4-5 frames │ ~200 Mbps (1080p60) │
│ │ H.264/265 │ High │ 5-15 frames│ 10-50 Mbps │
│ │
└─────────────────────────────────────────────────────────────────────┘
Pros & Cons for Digital Signage
| Pros | Cons |
|---|
| Unlimited distance (over network) | Higher per-endpoint cost |
| Any source to any display | Requires managed network |
| Easy to scale | Compression may affect quality |
| Centralized management | Network expertise needed |
| Uses existing IT infrastructure | Latency (protocol dependent) |
When to Use AV-over-IP
- Large enterprise deployments (100+ displays)
- Campus-wide distribution over existing network
- Video walls requiring flexible source switching
- Centralized control rooms managing multiple sources
- Future-proof installations requiring scalability
Comparison by Use Case
Recommended Connections by Scenario
| Scenario | Recommended | Alternative | Why |
|---|
| Single display, <5m | HDMI 2.0 | DisplayPort | Cost, simplicity |
| Single display, 5-15m | Active HDMI | HDBaseT | Reliability |
| Single display, 15-100m | HDBaseT | SDI | Single cable solution |
| Video wall (3-4 displays) | DisplayPort MST | HDMI + splitter | Daisy chain simplicity |
| Video wall (large) | AV-over-IP | SDI matrix | Flexibility, scalability |
| Outdoor LED | SDI | Fiber HDMI | Distance, reliability |
| Broadcast/studio | SDI | AV-over-IP (2110) | Industry standard |
| Enterprise (50+ displays) | AV-over-IP | HDBaseT matrix | Scalability |
Cable Quality & Installation Tips
General Best Practices
┌─────────────────────────────────────────────────────────────────────┐
│ CABLE INSTALLATION TIPS │
├─────────────────────────────────────────────────────────────────────┤
│ │
│ HDMI CABLES │
│ • Use "Premium High Speed" certified for 4K │
│ • Active cables for runs over 7m at 4K │
│ • Fiber HDMI for runs over 15m │
│ • Secure with HDMI locks or velcro │
│ • Avoid tight bends (min 3" radius) │
│ │
│ DISPLAYPORT CABLES │
│ • Use DP certified cables │
│ • Engage locking mechanism fully │
│ • VESA-certified for 8K (DP80) │
│ • Active cables for 4K over 5m │
│ │
│ SDI CABLES │
│ • Use appropriate grade for SDI version │
│ • Belden 1694A for 3G-SDI │
│ • Keep runs under max length for version │
│ • Proper BNC termination critical │
│ │
│ CAT6 (HDBaseT / AV-over-IP) │
│ • Solid core only (not stranded) │
│ • Cat6 minimum, Cat6A recommended │
│ • Shielded (STP) for noisy environments │
│ • Professional termination required │
│ • Test with cable certifier │
│ │
│ GENERAL RULES │
│ • Label both ends of every cable │
│ • Document cable runs in spreadsheet/diagram │
│ • Leave service loops at both ends │
│ • Separate video cables from power (parallel runs) │
│ • Use conduit in accessible areas │
│ │
└─────────────────────────────────────────────────────────────────────┘
Adapters & Converters
Common Conversion Scenarios
| From | To | Adapter Type | Notes |
|---|
| DisplayPort | HDMI | Passive adapter | Common, inexpensive |
| HDMI | DisplayPort | Active adapter | Requires power |
| SDI | HDMI | Converter box | Blackmagic, AJA |
| HDMI | SDI | Converter box | Adds latency |
| USB-C | HDMI/DP | Adapter/dock | Check alt mode support |
| VGA | HDMI | Active converter | Analog to digital |
Frequently Asked Questions
Next Steps
This guide covers current standards as of 2026. Connection standards evolve; verify specific cable and equipment capabilities for your installation. Maintained by MediaSignage, pioneers of digital signage technology since 2008.