Userland issue raspberrypi#76

Added  option to set the exposure/shutter time.

Needs a change on GPU binary, Brcm ref: 425060 and
a consequent change to
userland/interface/mmal/mmal_parameters_camera.h

There is currently a limitation of about 350ms beyond which
the camera will lock (depending on other settings). This
is being investigated, but is unrelated to this change
i.e. You can get the fault in other ways, not just by setting
the shutter speed.

host_applications/linux/apps/raspicam/RaspiCamControl.c

@@ -131,6 +131,7 @@ static const int metering_mode_map_size = sizeof(metering_mode_map)/sizeof(meter
 #define CommandHFlip       13
 #define CommandVFlip       14
 #define CommandROI         15
+#define CommandShutterSpeed 16
 
 static COMMAND_LIST  cmdline_commands[] =
 {
@@ -149,7 +150,8 @@ static COMMAND_LIST  cmdline_commands[] =
    {CommandRotation,    "-rotation",  "rot","Set image rotation (0-359)", 1},
    {CommandHFlip,       "-hflip",     "hf", "Set horizontal flip", 0},
    {CommandVFlip,       "-vflip",     "vf", "Set vertical flip", 0},
-   {CommandROI,         "-roi",       "roi","Set region of interest (x,y,w,d as normalised coordinates [0.0-1.0])", 1}
+   {CommandROI,         "-roi",       "roi","Set region of interest (x,y,w,d as normalised coordinates [0.0-1.0])", 1},
+   {CommandShutterSpeed,"-shutter",   "ss", "Set shutter speed in microseconds", 1}
 };
 
 static int cmdline_commands_size = sizeof(cmdline_commands) / sizeof(cmdline_commands[0]);
@@ -573,6 +575,12 @@ int raspicamcontrol_parse_cmdline(RASPICAM_CAMERA_PARAMETERS *params, const char
       break;
    }
 
+   case CommandShutterSpeed : // Shutter speed needs single number parameter
+      sscanf(arg2, "%d", &params->shutter_speed);
+      used = 2;
+      break;
+
+
    }
 
    return used;
@@ -704,6 +712,7 @@ void raspicamcontrol_set_defaults(RASPICAM_CAMERA_PARAMETERS *params)
    params->hflip = params->vflip = 0;
    params->roi.x = params->roi.y = 0.0;
    params->roi.w = params->roi.h = 1.0;
+   params->shutter_speed = 0;          // 0 = auto
 }
 
 /**
@@ -763,6 +772,7 @@ int raspicamcontrol_set_all_parameters(MMAL_COMPONENT_T *camera, const RASPICAM_
    result += raspicamcontrol_set_rotation(camera, params->rotation);
    result += raspicamcontrol_set_flips(camera, params->hflip, params->vflip);
    result += raspicamcontrol_set_ROI(camera, params->roi);
+   result += raspicamcontrol_set_shutter_speed(camera, params->shutter_speed);
 
    return result;
 }
@@ -1125,6 +1135,21 @@ int raspicamcontrol_set_ROI(MMAL_COMPONENT_T *camera, PARAM_FLOAT_RECT_T rect)
    return mmal_port_parameter_set(camera->control, &crop.hdr);
 }
 
+/**
+ * Adjust the exposure time used for images
+ * @param camera Pointer to camera component
+ * @param shutter speed in microseconds
+ * @return 0 if successful, non-zero if any parameters out of range
+ */
+int raspicamcontrol_set_shutter_speed(MMAL_COMPONENT_T *camera, int speed)
+{
+   if (!camera)
+      return 1;
+
+   return mmal_status_to_int(mmal_port_parameter_set_uint32(camera->control, MMAL_PARAMETER_SHUTTER_SPEED, speed));
+}
+
+
 
 /**
  * Asked GPU how much memory it has allocated

host_applications/linux/apps/raspicam/RaspiCamControl.h

@@ -129,6 +129,7 @@ typedef struct
    int hflip;                 /// 0 or 1
    int vflip;                 /// 0 or 1
    PARAM_FLOAT_RECT_T  roi;   /// region of interest to use on the sensor. Normalised [0,1] values in the rect
+   int shutter_speed;         /// 0 = auto, otherwise the shutter speed in ms
 } RASPICAM_CAMERA_PARAMETERS;
 
 
@@ -162,6 +163,7 @@ int raspicamcontrol_set_colourFX(MMAL_COMPONENT_T *camera, const MMAL_PARAM_COLO
 int raspicamcontrol_set_rotation(MMAL_COMPONENT_T *camera, int rotation);
 int raspicamcontrol_set_flips(MMAL_COMPONENT_T *camera, int hflip, int vflip);
 int raspicamcontrol_set_ROI(MMAL_COMPONENT_T *camera, PARAM_FLOAT_RECT_T rect);
+int raspicamcontrol_set_shutter_speed(MMAL_COMPONENT_T *camera, int speed_ms);
 
 //Individual getting functions
 int raspicamcontrol_get_saturation(MMAL_COMPONENT_T *camera);