Sensoray 817 - Manual (Page 5)

5
Data Types
All data types are defined in
s817.h . Integer types are 32-bit.
VIDEO_MODE
typedef struct {
MODE_TV_FORMAT
tvFormat;
MODE_JPG_SIZE jpgSize;
MODE_BMP_TYPE bmpType;
int
brightness;
int contrast;
int saturation;
int hue;
} VIDEO_MODE;
tvFormat
Defines TV format:
TV_NTSC for NTSC ,
TV_PAL for PAL .
Note : It is not recommended to switch the input signal from one TV standard to
another while the board is capturing. This may result in a lock up requiring
software restart.
jpgSize
Defines captured image size:
SIZE_4CIF - 640x480 (NTSC), 704x576 (PAL);
SIZE_4CIFI - 640x480 (NTSC), 704x576 (PAL), deinterlaced;
SIZE_2CIF - 640x240 (NTSC), 704x288 (PAL);
SIZE_1CIF - 320x240 (NTSC), 352x288 (PAL).
This parameter applies to both JPEG and bitmap captured images.
Images captured in
SIZE_2CIF format represent one field of interlaced video. Such
an image looks stretched in the horizontal direction, if displayed directly, but it does
not have motion artifacts characteristic to interlaced images. Capture of fields is
supported only at the frame rate (i.e. one field per frame, 30 fields per second for
NTSC, 25 for PAL).
Images captured in
SIZE_1CIF format represent one field of interlaced video scaled
down horizontally by a factor of 2. The same capture rate limitation as for
SIZE_2CIF applies.
Images captured in SIZE_4CIFI format have one field recreated by interpolating the
lines of another field. This removes motion artifacts at the expense of some losws of
vertical resolution.
PAL images captured in
SIZE_4CIF and SIZE_1CIF sizes have slightly distorted
aspect ratio of 1.222 instead of 1.333.
bmpType
Format of uncompressed image. Currently only monochrome 1 byte/pixel (Y8)
format is supported.