User`s guide

6 Working with Acquired Image Data
image data being provided by the device; the ROIPosition property specifies
the dimensions of the image frames being logged. See the
ROIPosition
property reference page for more information.
Example: Video Format and Image Dimensions
The following example illustrates how video format affects the size of the
image f rames returned.
1 Select a video format —Usetheimaqhwinfo function to view the list of
video forma ts supported by your image acquisition d evice. This exampl e
shows the video formats supported by a Matrox Orion frame grabber. The
formats are industry standard, such as RS170, NTSC, and PAL. These
standards define the image resolution.
info = imaqhwinfo('ma trox');
info.DeviceInfo.SupportedFormats
ans =
Columns 1 through 4
'M_RS170' 'M_R S170 _VIA_RGB' 'M_CCIR' 'M_CCIR_VIA_RGB'
Columns 5 through 8
'M_NTSC' 'M_NTS C_RG B' 'M_NTSC_YC' 'M_PAL'
Columns 9 through 10
'M_PAL_RGB' 'M_ PAL_ YC'
2 Create an im age acquisition object — Th i s example creates a video
input object for a Matrox image acquisition device using the default video
format, RS170. To run this example on your system, use the
imaqhwinfo
function to get the object constructor for your image acquisition device and
substitute that syntax for the following code.
vid = videoinput('mat rox',1);
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