DFK 33UX252 Technical Reference Manual
16
Camera Controls
5.1.1.4
YUV 4:1:1
This format transmits an 8-bit luminance value for every pixel and a pair of
chrominance values for every four pixels.
The two YUV 4:1:1 pixel formats only differ in their byte order.
The camera converts the raw pixel data from the sensor to YUV 4:2:2. Since YUV 4:2:2
averages to 1.5 bytes per pixel, the YUV 4:2:2 pixel format requires two 50% more
bandwidth than the 8-bit raw format, thus reducing the maximum possible frame rate.
USB3 Vision
drivers see this pixel format as
YCbCr411_8
and
YCbCr411_8_CbYYCrYY
.
UVC drivers see it with the
FourCC
Y411
.
The
Device Driver for The Imaging Source USB 33U, 37U and 38U Cameras
offers this
pixel format as the
Y411
video format.
5.1.1.5
RGB24
The camera converts the raw pixel data from the sensor to RGB24. Since RGB24 uses 3
bytes to store 1 pixel, the RGB24 pixel format requires three times the bandwidth of the
8-bit raw format, thus reducing the maximum possible frame rate.
USB3 Vision
drivers enumerate this pixel format as
BGR8
.
UVC drivers see it with the
FourCC
RGB24
.
The
Device Driver for The Imaging Source USB 33U, 37U and 38U Cameras
enumerates
this pixel format as the
RGB24
video format.
5.1.1.6
8-Bit Monochrome
The camera generates the pixel data by debayering the raw pixel data and transmitting
only the luminance information.
USB3 Vision
drivers enumerate this pixel format as
Mono8
.
UVC drivers do not have access to this format.
5.1.2
Resolution
The DFK 33UX252 allows the user to specify which rectangular region of the image
sensor to read out during camera operation. The size of this rectangle determines the
number of pixels that have to be transferred for each frame and has a significant
influence on the required USB bandwidth.
Lowering the resolution also often allows the image sensor to operate at a higher frame
rate. Changes in the vertical resolution have more effect on the maximum frame rate
than changes in the horizontal direction.
The way the resolution is controlled varies greatly between the driver technology used
to access the camera:
