Model 953-ET | 4-Channel A/V H.264 Encoder/Decoder


  • 4 input channels: 4 NTSC/PAL composite/S-Video + 4 stereo audio
  • H.264 HP@L3, MPEG-4 ASP, MJPEG video; AAC, G.711, PCM audio
  • Ultra-low latency video preview concurrent with compressed capture
  • Full duplex hardware encode/decode
  • Text overlay, GPIO
  • Supports both stack-up and stack-down
  • -40 to +85°C extended temperature range
  • SDKs for both Linux and Windows


Model 953-ET is a PCIe/104 form factor audio/video codec that simultaneously captures four channels of analog video and four channels of audio. Each video channel captures at up to full frame rate (30 fps for NTSC or 25 fps for PAL). Model 953 implements H.264, MJPEG, or MPEG-4 compression for video (with MPEG-TS supported), and G.711 or AAC for audio. A low-latency video preview stream is also provided for each channel.

Model 953 is capable of decoding compressed sreams in a full duplex mode (simultaneously with encoding). The decoded audio/video data is available on analog outputs.

The board's PCIe/104 connector supports both stack-up and stack-down, so that the board can be stacked anywhere in a PC/104 stack or an EPIC stack. The board's full conformance to the PCIe/104 and PCI/104-Express specification guarantees that it won't mechanically interfere with adjacent boards. All operating power is obtained from the PCIe/104 bus connector; no external power supply is needed.


The unit is capable of simultaneously producing two different video streams from its single composite video input and sending the streams out over the PCI-Express x1 link. One of the streams can be a low-latency stream (in umcompressed format and useful for real time previewing) and the other compressed, or both streams may be compressed. Image resolution, compression type and bit rate can all be independently configurable for each compressed stream.

Up to 1024 bytes of application-supplied data may be inserted in the H.264 or MPEG stream, at a specified frame interval or single shot.

Model 953-ET Sample Encoding Application

Stream Formats

Video and audio are available as elementary streams or may be multiplexed in MP4 container format.

Model 953-ET supports transport stream using AAC audio and H.264 or MPEG-4 video.


The Model 953-ET eliminates "lip sync" problems by implementing hardware-generated timestamps to keep audio synchronized to the video.

Digital I/O

One general purpose digital input and one output is provided for each channel. Both input and output are optically isolated. The input is sampled every millisecond, when a state change is detected a notification is sent to the application program.

Image Overlay

For each channel of video output, overlay images can be displayed on top of the composite video output. The overlayed video may be sourced from either the composite video input or a decoded compressed stream. Image formats supported are Windows bitmap (BMP) and Portable Network Graphics (PNG), with 24 or 32 bits per pixel. Overlays support 7 transparency levels.


The Model 953-ET can also perform as a 4-channel decoder, converting a compressed A/V stream into standard analog video and audio signals. Decoding is guaranteed only for the streams captured with the Sensoray Model 953-ET. The following formats are supported for decoding: MPEG-4 (.m4v), H.264 (.264 or .h264), MP4 (.mp4) and MJPEG (.mjpg or .mjpeg).

Ultra-low Latency Preview

The Model 953-ET supports an ultra-low latency preview mode for real-time applications. When capturing in native resolution (704x480 for NTSC or 704x576 for PAL) this mode reduces the overall latency by approximately one frame time to around 35 ms.


Software Development Kits (SDKs) are available for both Linux and Windows developers. The SDKs include drivers, programming examples and comprehensive documentation to enable the users and programmers to quickly develop custom application software for the Model 953-ET.


Sensoray offers breakout boards that route the 953-ET video, audio signals to standard connectors.

Model 953TA-Input provides connectors for four 3.5mm stereo audio inputs and four BNC composite video inputs.

Model 953TA-Input

Model 953TA-Output provides connectors for four 3.5mm stereo audio outputs and four BNC composite video outputs.

Model 953TAC1 cable connects a Model 953-ET board to the 953TA-Output breakout board. One of its three 16-pin connectors plugs into the 953-ET board, while one or both of the other connectors can be plugged into breakout boards.

953TAC1 Cable

Model 911TAC1 cable connects a Model 953-ET board to the 953TA-Input. One of its three 24-pin connectors plugs into the 953-ET board, while one or both of the other connectors can be plugged into breakout boards.

911TAC1 Cable


Inputs Channels 4 input channels, simultaneously
Formats NTSC, PAL
Connector 4 Composite video via a 24-pin connector
Impedance 75 Ω
Outputs Channels 4 input channels, simultaneously
Formats NTSC, PAL
Connector 4 Composite video via a 16-pin connector
Impedance 75 Ω
Capture Modes Raw digital frame or video, RGB or YUV
Frame Rate
30 frames/second per channel for NTSC/RS-170/CCIR
25 frames/second per channel for PAL/SECAM
Resolution Up to: 4 x D1 (NTSC: 720x480 / PAL: 720x576)
Encoding H.264 HP@L3, MPEG-4 ASP, or MJPEG
Output Stream Format Elementary Audio/Video, MPEG-4 Program Stream (.MP4), MJPEG Stream, Transport Stream
Video Preview Format 720x480 @30fps (NTSC) / 720x576 @25fps (PAL)
YUV4:2:2, GRAY8, or JPEG
Text Overlay Up to 160 characters with date and time stamp insertion
Inputs Channels 4 input channels: associated with 4 video channels
Signal level Line level, 1.0 Vpp
Connector Stereo or mono for each channel, via the same 24-pin connector
Outputs Channels 4 output channels: associated with 4 video channels
Signal level Line level, 1.0 Vpp
Connector Stereo or mono for each channel, via the same 16-pin connector
Capture Sampling Rate 48 kHz
Encoding G.711 or AAC
Digital I/O
Channels 4 inputs and 4 outputs
Signal Type All signals are isolated by optoisolators
Connector Break-in/out via a 18-pin connector
Bus Compliance PCI/104-Express & PCIe/104 Specification (Version 1.1)
PCI-Express Base Specification (Revision 1.1)
OS Platform Windows and Linux
Power Nominal < 7.5 W (1.5 A @ 5 V)
Temperature Operating Extended Industrial: -40 to 85 °C
Mechanical Dimensions (W x H): 3.775 x 3.55 inches; 96 x 90 mm


File Version Type Size
953-ET User Manual1.0.1PDF785 KB
953-ET Windows SDK Manual1.2.10PDF535 KB
953-ET Linux SDK Manual1.2.8PDF396 KB
Mechanical Drawings
953-ET Board Layout & Connector Pinout1.0.0PDF335 KB
Application Notes
SBC Compatibility1.0.0PDF318 KB


File Version Type Size
953 Linux SDK1.2.8BZ25.57 MB
953 Windows SDK1.2.11ZIP25.1 MB
Other Operating Systems
Need a software development kit for another operating system? We can port our SDK to
your OS or provide the information you need to port it yourself. Contact Sales for details.


Model Description Qty 1 Qty 2-9 Order Qty.
953-ET4-Channel A/V H.264 Encoder/Decoder$715$660
Breakout Boards
953TA-Input24 pin Breakout (audio in and composite video in)$69$63
953TA-Output16 pin Breakout (audio out and composite video out)$67$61
911TAC1Cable, video$7$7
953TAC1Cable, 16 conductor, for 953 breakout boards$7$7

SENSORAY | 7313 SW Tech Center Dr. | Tigard, OR 97223 | 503.684.8005 | Email Us

Privacy Policy | Copyright © 1982-2015 Sensoray