Technical Requirements

The following technical requirements are specific to each NDI format, but if a device can support more than one format, it will be certified and tested under both types separately.

In addition to the following technical requirements, Interoperability Requirements must be followed.

You can find other examples of bandwidth requirements on this page.

The transmission of NDI is agnostic to any specific aspect ration. You can expect it to work regardless of your resolution

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NDI High Bandwidth

The specific criteria for NDI High Bandwidth certification are:

• Interoperability requirements

• I Frame only for Keyframe

• Less than 100ms latency

• SpeedHQ codec

Resolution Supported	Framerates
2160p	60fps, 50fps, 30fps, 25fps
1080p	60fps, 50fps, 30fps, 25fps
1080i	60fps, 50fps
720p	60fps, 50fps, 30fps, 25fps
576i	50fps
480p	30fps, 25fps
480i	60fps

Codec	Supported Bit Depth	Chroma Subsampling	Color Space
SHQ0-7	8bit, 10bit	4:2:0, 4:2:2, 4:2:2:4	YUV

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NDI HX2

This certification is for products that support NDI HX2 but cannot pass the technical certification requirements of NDI HX3. Critically, they still pass the Interoperability requirements. These devices may have slower latency or keyframe or a larger GOP. The key criteria are:

• Interoperability requirements
• 150ms glass-to-glass latency

• Keyframe response time under 80ms

• Current SDK or previous SDK (6.0 currently, 5.6 previous as of this writing)

• H.264 or H.265 encoding

Resolution Supported	Framerates
2160p	60fps, 50fps, 30fps, 25fps
1080p	60fps, 50fps, 30fps, 25fps
720p	60fps, 50fps, 30fps, 25fps
480p	30fps, 25fps

Codec	Supported Bit Depth	Supported Chroma Subsampling	Color Space
H.264	8bit, 10bit	4:2:0, 4:2:0:4	YUV
H.265 HEVC	8bit, 10bit	4:2:0, 4:2:0:4	YUV

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NDI HX3

This certification is for products supporting NDI HX3 that fit one of the following criteria:

• Interoperability requirements

Encoder

• H.264 or H.265 encoding

• GOP setting set to 20

• Video compression set to low latency

Latency

• 100ms Glass-to-glass Latency

• Keyframe response time under 80ms

Compression

• Quality: no visible compression artifacts

• Compression: constant bitrate (CBR)

Resolution Supported	Framerates
2160p	60fps, 50fps, 30fps, 25fps
1080p	60fps, 50fps, 30fps, 25fps
720p	60fps, 50fps, 30fps, 25fps
480p	30fps, 25fps

Codec	Supported Bit Depth	Supported Chroma Subsampling	Color Space
H.264	8bit, 10bit	4:2:0, 4:2:0:4	YUV
H.265 HEVC	8bit, 10bit	4:2:0, 4:2:0:4	YUV

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NDI HX1 is a legacy format that will be discontinued over time. As such we are not certifying devices that support this format. Contact our technical support team if you have any questions.

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NDI 6 Optional Features

HDR

With NDI 6, HDR is now officially supported as a sender and receiver for NDI HX (HX2 and HX3 only) and NDI High Bandwidth. To qualify under either, the following must be met:

• HDR optional toggle - not every receiver is HDR compatible, and NDI strives for forward and backward compatibility. HDR must be allowed to turn off at the end user's request

• BT_2020 or BT_2100 primaries (as defined in the SDK for HDR)
• 10 and 12-bit video

NDI Bridge

With NDI 6, NDI Bridge functionalities can now be embedded into a device or application to connect across networks, even across the public Internet, easily. As this is a connection method rather than a quality metric, certification will depend on the ability to implement the following:

• NDI Bridge optional toggle - Bridge must be enabled or disabled at the end user's request

• Fields to enter IP, port, username, and password

• Connection success or failure messaging

We conduct testing on common industry standards, but certification only covers widely used resolutions and aspect ratios. Other resolutions and aspect ratios may work but are not officially certified at this time.