Editing UnifiedCameraAccess

= Unified Camera Access = `libuca` is a thin wrapper to make the different cameras (via !CameraLink or PCIe) accessible in an easy way. == Specification of Properties == Properties of cameras are accessed in a vendor-neutral way by specifying the property names as defined in [http://ufo.kit.edu/ufo/browser/vogelgesang/uca/src/uca.h uca.h]. The following list is the definite specification of basic properties that all devices must implement. If a property cannot be set or get via `uca_(get|set)_property()` the function shall return UCA_ERR_PROP_INVALID. ||= Property Name =||= Property String =||= Unit =||= Access =||= Meaning =|| || `UCA_PROP_NAME` || `name` || null-terminated C string || r || Name of camera || || `UCA_PROP_WIDTH` || `width` || pixels || r/w || Width of image to be taken || || `UCA_PROP_WIDTH_MIN` || `width.min` || pixels || r || Minimum width of image to be taken || || `UCA_PROP_WIDTH_MAX` || `width.max` || pixels || r || Maximum possible width || || `UCA_PROP_HEIGHT` || `height` || pixels || r/w || Height of image to be taken || || `UCA_PROP_HEIGHT_MIN` || `height.min` || pixels || r || Minimum height of image to be taken || || `UCA_PROP_HEIGHT_MAX` || `height.max` || pixels || r || Maximum possible height || || `UCA_PROP_X_OFFSET` || `x-offset` || pixels || r/w || Horizontal coordinate of start of ROI || || `UCA_PROP_Y_OFFSET` || `y-offset` || pixels || r/w || Vertical coordinate of start of ROI || || `UCA_PROP_BITDEPTH` || `bit-depth` || number of bits || r || Bits per pixel || || `UCA_PROP_EXPOSURE` || `exposure` || microseconds || r/w || Duration of image capture || || `UCA_PROP_DELAY` || `delay` || microseconds || r/w || Delay before image capture || || `UCA_PROP_FRAMERATE` || `frame-rate` || frames per second || r || Current number of frames per second || || `UCA_PROP_TRIGGER_MODE` || `trigger-mode` || see below || r/w || Trigger mode for shutter opening || The following table lists special properties that are ignored (and also flagged with an `UCA_ERR_PROP_INVALID` return value) by cameras that don't support them: ||= Property Name =||= Property String =||= Unit =||= Access =||= Meaning =|| || `UCA_PROP_TIMESTAMP_MODE` || `timestamp-mode` || bitmask (see below) || r/w || Print a timestamp || || `UCA_PROP_INTERLACE_SAMPLE_RATE` || `interlace-sample-rate` || integer quantity || r/w || Take only every `interlace-sample-rate` rows into account for the Fast-Reject algorithm || || `UCA_PROP_INTERLACE_PIXEL_THRESH` || `interlace-pixel-threshold` || number of pixels || r/w || Row is classified as triggered, when more than `interlace-row-threshold` pixels trigger || || `UCA_PROP_INTERLACE_ROW_THRESH` || `interlace-row-threshold` || number of rows || r/w || Ignore row trigger when less than `interlace-row-threshold` rows trigger || || `UCA_PROP_CORRECTION_MODE` || `correction-mode` || bitmask (see below) || r/w || Enable/disable certain correction modes || === Values === `UCA_PROP_TIMESTAMP_MODE` (boolean combinations possible): ||= Timestamp bit =||= Meaning =|| || UCA_TIMESTAMP_BINARY || Binary encoded timestamp || || UCA_TIMESTAMP_ASCII || Human-readable ASCII timestamp || `UCA_PROP_TRIGGER_MODE`: ||= Trigger Name =||= Meaning =|| || `UCA_TRIGGER_AUTO` || Free run mode || || `UCA_TRIGGER_INTERNAL` || Trigger via !CameraLink interface || || `UCA_TRIGGER_EXTERNAL` || Trigger via external hardware || `UCA_PROP_CORRECTION_MODE` (boolean combinations possible): ||= Correction bit =||= Meaning =|| || `UCA_CORRECT_OFFSET` || Remove static fixed-pattern noise using a black-reference image || || `UCA_CORRECT_HOTPIXEL` || Interpolate marked hot pixels as average of surrounding pixels || || `UCA_CORRECT_GAIN` || Apply correction to each pixel for linear behaviour || == Code == Followingly, we will build libpco (the hardware-dependent pco.edge "driver") and libuca. First of all, get the sources {{{ #!sh cd some-empty-dir bzr clone bzr+ssh://user@ufo.kit.edu/vogelgesang/pco-diag libpco bzr clone bzr+ssh://user@ufo.kit.edu/vogelgesang/uca libuca }}} Make sure, that you have installed the Silicon Software [http://www.silicon-software.de/download.html Runtime Environment]. Then build and install libpco using {{{ #!sh mkdir build && cd build cmake ../libpco make && sudo make install }}} If everything went okay, you can try the `diagnose` program in the build directory. It tries to open the camera and frame grabber, prints out some information and stores one frame as `out.raw`. Finally, you can build libuca {{{ #!sh rm -rf * cmake ../libuca make }}} == Using libuca == The following test program is supplied with `libuca` and demonstrates the general functionality of the library: {{{ #!c #include <stdio.h> #include "uca.h" int main(int argc, char *argv[]) { struct uca_t *uca = uca_init(); if (uca == NULL) { printf("Couldn't find a camera\n"); return 1; } uint32_t width = 800, height = 600; uca->cam_set_property(uca, UCA_PROP_WIDTH, &width); uca->cam_set_property(uca, UCA_PROP_HEIGHT, &height); char camera_name[256] = "foobar"; uca->cam_get_property(uca, UCA_PROP_NAME, camera_name); printf("Camera name: %s\n", camera_name); uca_destroy(uca); return 0; } }}}