All the PicPort® models are based on similar architecture, so let us look through it.
I/O interface here stands for video input connectors, synchronization and optoisolated trigger inputs and outputs and other plugs. The interface is model-specific and will be described later in details.
PicPort® cards feature one (PicPort®-Stereo models two) digitizer channels, each of them handling up to 4 video inputs. Besides the A/D converter, each digitizer channel contains additional circuits for image preprocessing. The available functionality is dependent on PicPort® version (see description of all the models).
The Pixel Stream Manager is the real heart of every PicPort®. It consists of two data paths (DMA channels) with different features (see the figure). Data path A features following circuits: High Performance Scaler for fine interpolating, detail-preserving image scaling down to about 40×40 pixels and horizontal plus vertical mirroring, Lock Mask Control for text or graphics overlay on the top of the live image and Pixel Packer and Color Space Converter which performs conversion to desired color format. Such features are very useful for image display on a monitor.
The second data path B contains only the Binary Ratio Scaler (rough image scaling by skipping pixels, mirroring), which allows high speed processing of the image potentially displayed by data path A. The path B is also used for reverse data transfer from PCI bus to PicPort®-Connect interface.
Both data paths contain FIFO buffers for proper synchronizing the DMA transfers.
This unique bi-directional interface (allowing exchange of both, commands and image data) enables usage of optional hardware extension plug-in modules provided by Leutron Vision or by third party OEM developers.
Not shown in the figure.
The operating system (Microsoft Windows) cannot handle real time critical tasks such as acquiring image sequences. That’s why PicPort® boards feature on board programmable intelligence to guarantee performance of such tasks independently of other activities on the PC (i.e. independently of the host processor).
Not shown in the figure.
Electronically Erasable Programmable ROM serves for saving firmware information which is automatically administered by our software. Thus the user need not deal with differences between various hardware/firmware releases of the boards.
As the image transfer rate to the host is one of the most critical claims for most applications, the PicPort® boards were projected for and should be used with PCI bus Rev. 2.1 compliant hardware (chipset and graphic adapter, see our recommendations). Thus peak image data transfer rates of 132 MB/s are assured.
The cards are able to digitize video image from various color (PAL, SECAM, NTSC, S-video) or monochrome (CCIR, RS170) sources; moreover, arbitrary nonstandard (easily user-defined) video sources are supported.
Up to eight cameras can be interfaced to one board with no delay in switching between them; in case of PicPort®-Stereo, two signals can be digitized at the same time. The number of PicPort® boards that can be operated by single PC is only limited by the number of free PCI slots. The input image is preprocessed, manipulated and transferred via PCI bus to host and/or video memory for potential further processing.
Moreover, all the cards are equipped with a special two-way interface (PicPort®-Connect) for optional hardware extension modules, to allow user to enhance framegrabber's capabilities in a modular way.
All offered models are available in versions for CompactPCI systems. The PicPort®-Color is provided also in Industrial PCI (SIPS) version.