Description

Model 2255 captures uncompressed frames from four NTSC or PAL video sources and sends them over USB 2.0 to a host computer. Frames are captured simultaneously from all channels. The maximum aggregate rate in full resolution color mode is 60/50 fps (NTSC/PAL), yielding a per-channel NTSC capture frame rate of 30 fps for 2 channels, or 15 fps for four channels. In monochrome and/or scaled down modes all four channels can capture at full frame rate.

Model 2255 block diagram

Model 2257 is functionally identical to the 2255 except for input types: Model 2255 has four composite video inputs, while Model 2257 has two S-Video and two composite inputs. Both units support a variety of output resolutions and formats, eliminating the need for the application program to perform format and resolution conversions. The units are capable of capturing frames in any of these formats:

• RGB packed (24 bits/pixel, bitmap compatible)
• YCrCb packed (16 bits/pixel, YUY2 compatible)
• YCrCb planar (16 bits/pixel, optimal for image processing)
• Y8 (8 bits/pixel, monochrome)

The units support Y8 and YCrCb planar natively, while conversions to RGB and YCrCb packed formats are optionally performed by Sensoray drivers. Please refer to the 2255 software documentation for details.

Each unit has a serial number that can be read through the API, thus enabling the application software to easily identify specific units in multi-unit systems.

Low latency

Models 2255/2257 have exceptionally low latency, making them especially useful in applications that require fast visual feedback.

Deinterlacing

Models 2255/2257 are capable of performing advanced video deinterlacing to reduce motion artifacts in captured images. Deinterlacing is performed by hardware so that the host computer is not burdened with this task.

No deinterlacing

With deinterlacing

Software

Sensoray offers several free, downloadable Software Development Kits (SDKs) to enable OEMs to quickly integrate Model 2255/2257 units into application systems:

• Windows API. This is recommended for most Windows applications. Image buffers are allocated by the application and then registered with the driver, thereby greatly simplifying both custom application development and integration with third-party image processing software.
• Direct Show API for Windows. This is recommended only for Direct Show application development.
• Linux API, which includes Video4Linux2 (V4L2) support.

An optional driver version is available that enables hardware JPEG compression. This facilitates JPEG capture at 30 fps on two channels, or on four channels at 15 fps. The standard driver (included with free SDK) supports a limited preview of the JPEG capture capability. To purchase the JPEG-enabled driver, please contact Sensoray sales.

Mounting options

The 2255 is available as an OEM bare board (Model 2255), in a metal enclosure (Model 2255S), or mounted on a PC expansion bracket (Model 2255S-PC). For OEM applications, the unit can be custom-ordered to include high density headers in place of the standard connectors (Model 2255-NC).

The 2257 is available as an OEM bare board (Model 2257) or in a metal enclosure (Model 2257S).

Specifications

System requirements: USB 2.0 high-speed port, PIII 700 MHz CPU or equivalent. A high performance CPU is recommended for applications in which heavy image processing is performed.

Activation of deinterlacing is optional; when active, it reduces the maximum capture rate by a few percent.

Video
Inputs	Type	2255: 4 composite (BNC) 2257: 2 composite, 2 S-Video
	Video format	NTSC (M), PAL (BDGHIMN)
Output	Resolution	NTSC: 640 x 480, 320 x 240, 640 x 240 PAL: 704 x 576, 352 x 288, 704 x 288
Maximum capture rate (from all channels)	Color, full size	60 (50) fps (NTSC/PAL)
	Monochrome and/or scaled down	120 (100) fps (NTSC/PAL)
Other
USB	Current (max)	470 mA
Mechanical	Weight	2255S (with enclosure): 0.58 lbs 2255 (without enclosure): 0.25 lbs

Documentation

File	Version	Type	Size	Last Updated
Model 2255 / 2257 Hardware and Software Manual	1.0.4	PDF	398 KB	30 Jun 2011
2255 dimensions	n/a	PDF	129 KB	25 Sep 2009
2257 dimensions	n/a	PDF	113 KB	13 Oct 2010

Downloads

File	Version	Type	Size	Last Updated
Software Development Kits
Windows Drivers and SDK	1.1.5	ZIP	1.96 MB	24 Jan 2012
Windows Direct Show SDK	1.1.4	ZIP	954 KB	14 Mar 2011
Linux drivers and SDK	1.1.26	BZ2	235 KB	6 Apr 2011
Firmware
USB firmware update	0.3.12	ZIP	105 KB	14 Mar 2011

Prices

Model	Description	Qty 1	Qty 2-9
2255S	USB frame grabber with enclosure	$515	$468
2255	USB 4-Channel Frame Grabber	$467	$424
2255S-PC	USB frame grabber without enclosure, with bracket	$487	$444
2257	USB 4-Channel frame grabber with 2 S-Video + 2 composite inputs	$call	$call
2255-NC	USB frame grabber with high density headers	$call	$call
SDK2255-E	Optional JPEG encoding firmware for model 2255	$call	$call
2250C1	1-meter USB cable (supplied with enclosed model only)	$3	$3