The dcam1394 driver supports devices implementing the 1394 Trade Association Digital Camera Specification (also referred to as the IIDC specification). Only a subset of the specification is supported.
READING DATA
Isochronous data is read from the driver frame-by-frame and is maintained within the driver in a ring buffer.
Video frames are read from the isochronous input device using read(2).
The dcam1394_frame_t structure describes the frame layout and is defined as follows:
struct {
unsigned int vid_mode;
unsigned int seq_num;
hrtime_t timestamp;
unsigned char *buff;
};
The size to allocate for the structure is determined by the video mode for which the camera is configured. Possible values for the vid_mode field are listed under DCAM1394_PARAM_VID_MODE below.
IOCTL REQUESTS
The following ioctl requests are supported:
DCAM1394_CMD_CAM_RESET
Reset the device.
DCAM1394_CMD_REG_READ
Read the indicated dcam/IIDC register. The argument is a pointer to a dcam1394_reg_io_t structure, which is defined as follows:
struct {
unsigned int offs;
unsigned int val;
};
The offs field should be set to the offset of the register from which to read. Register offset values are defined in the 1394 Trade Association Digital Camera Specification.
After the operation is completed, the camera register value is put in the val field.
DCAM1394_CMD_REG_WRITE
Write the indicated dcam/IIDC register. The argument is a pointer to a dcam1394_reg_io_t structure (described above).
The offs field should be set to the offset of the register from which to read. The register offset values are defined in the 1394 Trade Association Digital Camera Specification.
The val field should be set to the value to be written to the camera register.
DCAM1394_CMD_PARAM_GET
Gets a list of parameters associated with a camera. The argument is a pointer to a dcam1394_param_list_t structure (described below). The parameter list is accessed through macros defined below.
The paramter list only supports Format 1 video formats.
DCAM1394_CMD_PARAM_SET
Sets a list of parameters associated with a camera. The argument is a pointer to a dcam1394_param_list_t structure (described below). The parameter list is accessed through macros defined below.
The paramter list only supports Format 1 video formats.
DCAM1394_CMD_FRAME_RCV_START
Start receiving video frames from the camera.
The contents of the ring buffer may be accessed by reading the isochronous stream device.
DCAM1394_CMD_FRAME_RCV_STOP
Stop receiving frames from the camera.
DCAM1394_CMD_RING_BUFF_FLUSH
Flush the frames in the ring buffer.
DCAM1394_CMD_FRAME_SEQ_NUM_COUNT_RESET
Reset frame sequence number.
PARAMETER LIST ACCESS
The parameter list is initialized and access through macros. The data type for the parameter list is dcam1394_param_list_t.
The following macros are used to access the parameter list:
PARAM_LIST_INIT(param_list)
Initialize the parameter list.
PARAM_LIST_ADD(param_list, param, subparam)
Add a parameter to the list.
PARAM_LIST_REMOVE(param_list, param, subparam)
Remove a parameter from the list.
PARAM_LIST_IS_ENTRY(param_list, param, subparam)
Indicates if a specific parameter is in the list.
PARAM_VAL(param_list, param, subparam)
Value of a specified parameter.
PARAM_ERR(param_list, param, subparam)
Indicates if a specific parameter is successfully set.
When no subparam value is required, the value DCAM1394_SUBPARAM_NONE may be used.
PARAMETERS
The following parameters may appear in the list:
DCAM1394_PARAM_CAP_POWER_CTRL
Queries if the camera can be turned off and on through software. The subparam value is ignored.
DCAM1394_PARAM_POWER
Controls or queries if the camera is powered up. Verify this feature using DCAM1394_PARAM_CAP_POWER_CTRL before use. The subparam field is ignored.
DCAM1394_PARAM_CAP_VID_MOD
Queries if a specific video mode is supported by the camera.
subparam is one of the following and is used to determine if a specified video mode is supported by the camera:
DCAM1394_SUBPARAM_VID_MODE_0
DCAM1394_SUBPARAM_VID_MODE_YUV_444_160_120
Video mode is 4:4:4, YUV color space, 160x120 resolution.
DCAM1394_SUBPARAM_VID_MODE_1
DCAM1394_SUBPARAM_VID_MODE_YUV_422_320_240
Video mode is 4:2:2, YUV color space, 320x240 resolution.
DCAM1394_SUBPARAM_VID_MODE_2
DCAM1394_SUBPARAM_VID_MODE_YUV_411_640_480
Video mode is 4:1:1, YUV color space, 640x480 resolution.
DCAM1394_SUBPARAM_VID_MODE_3
DCAM1394_SUBPARAM_VID_MODE_YUV_422_640_480
Video mode is 4:2:2, YUV color space, 640x480 resolution.
DCAM1394_SUBPARAM_VID_MODE_4
DCAM1394_SUBPARAM_VID_MODE_RGB_640_480
Video mode is RGB color space, 640x480 resolution.
DCAM1394_SUBPARAM_VID_MODE_5
DCAM1394_SUBPARAM_VID_MODE_Y_640_480
Video mode is Y color space, 640x480 resolution.
DCAM1394_PARAM_VID_MODE
Controls or queries the current video mode of the camera. The subparam field is ignored. When selecting the video mode, it should be compatible with the capability of the camera, which may be determined by checking the DCAM1394_PARAM_CAP_VID_MODE
parameter.
The value of this parameter may be one of the following:
DCAM1394_VID_MODE_0
DCAM1394_VID_MODE_YUV_444_160_120
Video mode is 4:4:4, YUV color space, 160x120 resolution.
DCAM1394_VID_MODE_1
DCAM1394_VID_MODE_YUV_422_320_240
Video mode is 4:2:2, YUV color space, 320x240 resolution.
DCAM1394_VID_MODE_2
DCAM1394_VID_MODE_YUV_411_640_480
Video mode is 4:1:1, YUV color space, 640x480 resolution.
DCAM1394_VID_MODE_3
DCAM1394_VID_MODE_YUV_422_640_480
Video mode is 4:2:2, YUV color space, 640x480 resolution.
DCAM1394_VID_MODE_4
DCAM1394_VID_MODE_RGB_640_480
Video mode is RGB color space, 640x480 resolution.
DCAM1394_VID_MODE_5
DCAM1394_VID_MODE_Y_640_480
Video mode is Y color space, 640x480 resolution.
DCAM1394_PARAM_CAP_FRAME_RATE_VID_MODE_0
Queries if a specific frame rate is supported by the camera in video mode 0 (4:4:4, YUV, 160x120).
subparam is one of the following and used to determine if a specified frame rate is supported by the camera:
DCAM1394_SUBPARAM_FRAME_RATE_0
DCAM1394_SUBPARAM_FRAME_RATE_3_75_FPS
Frame rate is 3.75 frames/second.
DCAM1394_SUBPARAM_FRAME_RATE_1
DCAM1394_SUBPARAM_FRAME_RATE_7_5_FPS
Frame rate is 7.5 frames/second.
DCAM1394_SUBPARAM_FRAME_RATE_2
DCAM1394_SUBPARAM_FRAME_RATE_15_FPS
Frame rate is 15 frames/second.
DCAM1394_SUBPARAM_FRAME_RATE_3
DCAM1394_SUBPARAM_FRAME_RATE_30_FPS
Frame rate is 30 frames/second.
DCAM1394_SUBPARAM_FRAME_RATE_4
DCAM1394_SUBPARAM_FRAME_RATE_60_FPS
Frame rate is 60 frames/second.
DCAM1394_PARAM_CAP_FRAME_RATE_VID_MODE_1
Queries if a specific frame rate is supported by the camera in video mode 1 (4:2:2, YUV, 320x240). See DCAM1394_PARAM_CAP_FRAME_RATE_VID_MODE_0 for a listing of valid subparam values.
DCAM1394_PARAM_CAP_FRAME_RATE_VID_MODE_2
Queries if a specific frame rate is supported by the camera in video mode 2 (4:1:1, YUV, 640x480). See DCAM1394_PARAM_CAP_FRAME_RATE_VID_MODE_0 for a listing of valid subparam values.
DCAM1394_PARAM_CAP_FRAME_RATE_VID_MODE_3
Queries if a specific frame rate is supported by the camera in video mode 3 (4:2:2, YUV, 640x480). See DCAM1394_PARAM_CAP_FRAME_RATE_VID_MODE_0 for a listing of valid subparam values.
DCAM1394_PARAM_CAP_FRAME_RATE_VID_MODE_4
Queries if a specific frame rate is supported by the camera in video mode 4. (RGB, 640x480). See DCAM1394_PARAM_CAP_FRAME_RATE_VID_MODE_0 for a listing of valid subparam values.
DCAM1394_PARAM_CAP_FRAME_RATE_VID_MODE_5
Queries if a specific frame rate is supported by the camera in video mode 5. (Y, 640x480). See DCAM1394_PARAM_CAP_FRAME_RATE_VID_MODE_0 for a listing of valid subparam values.
DCAM1394_PARAM_FRAME_RATE
Controls or queries the current frame rate of the camera. The subparam field is ignored. When selecting a frame rate, it should be compatible with the capability of the camera, which can be determined by querying one of the frame rate
capability parameters above.
The value of this parameter may be one of the following:
DCAM1394_FRAME_RATE_0
DCAM1394_3_75_FPS
The frame rate is 3.75 frames per second.
DCAM1394_FRAME_RATE_1
DCAM1394_7_5_FPS
The frame rate is 7.5 frames per second.
DCAM1394_FRAME_RATE_2
DCAM1394_15_FPS
The frame rate is 15 frames per second.
DCAM1394_FRAME_RATE_3
DCAM1394_30_FPS
The frame rate is 30 frames per second.
DCAM1394_FRAME_RATE_4
DCAM1394_60_FPS
The frame rate is 60 frames per second.
DCAM1394_PARAM_RING_BUFF_CAPACITY
Controls or queries the number of frames that the ring buffer may hold. This value can range between 2 and 30. The subparam field is ignored.
DCAM1394_PARAM_RING_BUFF_NUM_FRAMES_READY
Queries the number of frames in the ring buffer ready to be accessed. The subparam field is ignored.
DCAM1394_PARAM_RING_BUFF_READ_PTR_INCR
Controls or queries the number of bytes to advance the read pointer as it consumes data from the ring buffer. The subparam field is ignored.
DCAM1394_PARAM_FRAME_NUM_BYTES
Queries the number of bytes in a frame at the current video mode. The subparam field is ignored.
DCAM1394_PARAM_STATUS
Queries the parameter status. The subparam field is ignored.
The values for the parameter status is a bit field with the following values possibly set:
DCAM1394_STATUS_FRAME_RCV_DONE
Frame successfully received.
DCAM1394_STATUS_RING_BUFF_LOST_FRAME
A frame has been lost while processing the ring buffer.
DCAM1394_STATUS_PARAM_CHANGE
A parameter has been changed.
DCAM1394_STATUS_FRAME_SEQ_NUM_COUNT_OVERFLOW
Frame sequence number has reached its maximum possible value and has overflowed.
DCAM1394_STATUS_CAM_UNPLUG
Camera has been unplugged.
DCAM1394_PARAM_BRIGHTNESS
Query or control a camera feature. This feature queries or controls the brightness of the camera.
DCAM1394_SUBPARAM_PRESENCE
Indicates if the feature is available.
DCAM1394_SUBPARAM_CAP_ON_OFF
Indicates if the feature may be enabled and disabled. May only be queried.
DCAM1394_SUBPARAM_ON_OFF
Indicates if the feature is enabled.
DCAM1394_SUBPARAM_CAP_CTRL_AUTO
Indicates if the automatic control of this feature is supported by the camera. May only be queried.
DCAM1394_SUBPARAM_CAP_CTRL_MANUAL
Indicates if the manual control of this feature is supported by the camera. May only be queried.
DCAM1394_SUBPARAM_CTRL_MODE
Indicates if the feature is in auto or manual mode.
DCAM1394_SUBPARAM_MIN_VAL
Minimum value of the feature. May only be queried.
DCAM1394_SUBPARAM_MAX_VAL
Maximum value of the feature. May only be queried.
DCAM1394_SUBPARAM_VALUE
Current value of the feature.
DCAM1394_SUBPARAM_CAP_READ
Indicates if the feature may be read. May only be queried.
DCAM1394_PARAM_EXPOSURE
Query or control a camera feature. This feature queries or controls the exposure of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DCAM1394_PARAM_SHARPNESS
Query or control a camera feature. This feature queries or controls the sharpness of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DCAM1394_PARAM_WHITE_BALANCE
Query or control a camera feature. This feature queries or controls the white balance of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS, except for DCAM1394_SUBPARAM_VALUE. DCAM1394_SUBPARAM_VALUE
is replaced by two distinct subparams.
DCAM1394_SUBPARAM_U_VALUE
U or B component of the white balance.
DCAM1394_SUBPARAM_V_VALUE
V or R component of the white balance.
DCAM1394_PARAM_HUE
Query or control a camera feature. This feature queries or controls the hue of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DCAM1394_PARAM_SATURATION
Query or control a camera feature. This feature queries or controls the saturation of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DCAM1394_PARAM_GAMMA
Query or control a camera feature. This feature queries or controls the gamma of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DCAM1394_PARAM_SHUTTER
Query or control a camera feature. This feature queries or controls the sharpness of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DCAM1394_PARAM_GAIN
Query or control a camera feature. This feature queries or controls the gain of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DCAM1394_PARAM_IRIS
Query or control a camera feature. This feature queries or controls the iris of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DCAM1394_PARAM_FOCUS
Query or control a camera feature. This feature queries or controls the focus of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DCAM1394_PARAM_ZOOM
Query or control a camera feature. This feature queries or controls the zoom of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DCAM1394_PARAM_PAN
Query or control a camera feature. This feature queries or controls the pan of the camera. The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DCAM1394_PARAM_TILT
Query or control a camera feature. This feature queries or controls the tilt of the camera.The subparams supported by this feature are described under DCAM1394_PARAM_BRIGHTNESS.
DEVICE SPECIAL FILES
/dev/dcamN
Device node for isochronous input from camera.
/dev/dcamctlN
Device node for camera control.
FILES
kernel/drv/sparcv9/dcam1394
64-bit ELF kernel module.
kernel/drv/dcam1394
32-bit ELF kernel module.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes: