User`s guide

Creating Image Acquisition Objects
The following sections describe these options. If you do not specify a video
format, the
videoinput function uses one of the video formats supported by
the device. For Matrox and Data Translation devices, it chooses the RS170
video format. For Windows devices, it us es the first RG B format in the list of
supported formats or, if no RGB formats are supported, the device’s default
format.
Using a Video Format String
To specify a video format as a text string, use the imaqhwin fo function to
determine the list of supported formats. The
imaqhwinfo function returns
this information in the
SupportedFormats field of the device information
structure. See “Determining Supported Video Formats” o n page 4-6 for more
information.
In this example, each of the text strings is a video format supported by a
Matrox device.
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'
For Matrox devices, the toolbox uses the RS170 format as the d efault. (To find
out which is the default video format, look in the
DefaultFormat field of the
device information structure returned by the
imaqhwinfo function.)
4-13