Buffer types

ifm3d supports multiple device families (O3R, O3D3xx, O3X1xx).

Each device natively provides different types of data, and the ifm3d library adds additional buffers for convenience.

The tables below list all available buffer types and which device they apply to. We also specify if the data is provided directly by the device, meaning it is streamed from the embedded device, or calculated by ifm3d API on the receiver device. This is important information to be considered when trying to work around bandwidth limitations and delays.

In this tables, the NA abbreviation stands for “Not Applicable.”

O3R Available buffers

buffer_id	Description	Native or calculated in ifm3d
ALGO_DEBUG	Proprietary data used for troubleshooting by ifm. For internal use only.	Native
CONFIDENCE_IMAGE	2D image containing information about each pixel status. Only available for the 3D ports.	Native
EXTRINSIC_CALIB	Current values of the optical system to user coordinate transformation for the port currently targeted by the FrameGrabber. Only available for the 3D port. Can also be retrieved with the TOF_INFO buffer.	Calculated
INTRINSIC_CALIB	The intrinsic parameters for the port or camera currently targeted by theFrameGrabber. Only available for the 3D port. Can also be retrieved with the TOF_INFO buffer.	Native
INVERSE_INTRINSIC_CALIBRATION	The inverse intrinsic parameters for the port or camera currently targeted by theFrameGrabber. Only available for the 3D port. Can also be retrieved with the TOF_INFO	Native
JPEG_IMAGE	The 2D RGB image.	Native
NORM_AMPLITUDE_IMAGE	The normalized amplitude image.	Native
O3R_ODS_INFO	The zones output of ODS. Only available for devices with an ODS license.	Native
O3R_ODS_OCCUPANCY_GRID	The occupancy grid output of ODS. Only available for devices with an ODS license.	Native
O3R_RESULT_ARRAY2D	Contains the result for O3R applications like PDS and MCC.	Native
O3R_RESULT_IMU	The IMU data for the OVP on-board IMU at port 6.	Native
O3R_RESULT_JSON	Contains the result for O3R applications like PDS and MCC.	Native
RADIAL_DISTANCE_IMAGE	2D image containing the radial distance value for each pixel.	Native
RADIAL_DISTANCE_NOISE	2D image containing the distance noise value for each pixel.	Native
REFLECTIVITY	2D image containing the estimated IR reflectivity (in percent). Only available for the 3D ports.	Native
RGB_INFO	Contains various information about the RGB camera and the latest RGB frame (seeRGBInfoV1)	Native
TOF_INFO	Contains various information about the TOF camera and the latest TOF frame (seeTOFInfoV4)	Native
XYZ	The point cloud in Cartesian coordinates.	Calculated

O3D Available buffers

buffer_id	Description	Native or calculated in ifm3d
AMPLITUDE_IMAGE	2D image containing amplitude information for each pixel.	Native
CARTESIAN_X_COMPONENT	Cartesian coordinate along X axis.	Calculated
CARTESIAN_Y_COMPONENT	Cartesian coordinate along Y axis.	Calculated
CARTESIAN_Z_COMPONENT	Cartesian coordinate along Z axis.	Calculated
CONFIDENCE_IMAGE	2D image containing information about each pixel status.	Native
DIAGNOSTIC	Provides some diagnostic information. See details below.	Native
EXPOSURE_TIME	Exposure times used for the last frame.	Calculated
EXTRINSIC_CALIB	Current values of the optical system to user coordinate transformation for the port currently targeted by the FrameGrabber.	Calculated
ILLUMINATION_TEMP	The temperature of the illumination module	Native
INTRINSIC_CALIB	The intrinsic parameters for the port or camera currently targeted by theFrameGrabber.	Native
INVERSE_INTRINSIC_CALIBRATION	The inverse intrinsic parameters for the port or camera currently targeted by theFrameGrabber.	Native
JSON_DIAGNOSTIC	Diagnostic information in JSON format.	Native
JSON_MODEL	For internal use only.	??
NORM_AMPLITUDE_IMAGE	The normalized amplitude image.	Native
RADIAL_DISTANCE_IMAGE	2D image containing the radial distance value for each pixel.	Native
UNIT_VECTOR_ALL	Unit vectors that can be used to calculate the point cloud directly from the distance image.	Native
XYZ	The point cloud in Cartesian coordinates.	Calculated

Note

The CARTESIAN_ALL buffer is deprecated, and the XYZ buffer should be used instead.

DIAGNOSTIC buffer

This buffer provides diagnostic information such as temperature, frame duration and framerate.

To unpack the information in the DIAGNOSTIC buffer, use the following structure:

Content	Type	Size
Illumination temperature	32-bit signed int	4 bytes
Frontend Temperature 1	32-bit signed int	4 bytes
Frontend Temperature 2	32-bit signed int	4 bytes
i.mx6 Temperature	32-bit signed int	4 bytes
Frame duration: time between the last trigger and the readiness for a new trigger. Only relevant in triggered mode.	32-bit unsigned integer	4 bytes
Framerate. Only relevant in continuous mode (also called free running mode).	32-bit unsigned integer	4 bytes

Note

All the temperatures are displayed in 0.1 °C. Invalid temperatures have the value 0x7FFF (32767). Some temperatures are only measured for specific part numbers, which might be why they are invalid.

In Python, the DIAGNOSTIC data can be unpacked with:

# Necessary imports
import struct
import time
from ifm3dpy.device import O3D
from ifm3dpy.framegrabber import FrameGrabber, buffer_id

# Create the objects
o3d = O3D() #EDIT here when using a non-default IP address
fg = FrameGrabber(o3d)

#Collect a frame
fg.start([buffer_id.DIAGNOSTIC,])
time.sleep(5) # Grace period after initialization of the data stream
[ok, frame] = fg.wait_for_frame().wait_for(500)

# Get the data from the collected frame 
data = frame.get_buffer(buffer_id.DIAGNOSTIC)
# Unpack the data 
unpacked_data = struct.unpack('<4i2I', data)

fg.stop()

O3X Available buffers

buffer_id	Description	Native or calculated in ifm3d
CARTESIAN_X_COMPONENT	Cartesian coordinate along X axis.	Calculated
CARTESIAN_Y_COMPONENT	Cartesian coordinate along Y axis.	Calculated
CARTESIAN_Z_COMPONENT	Cartesian coordinate along Z axis.	Calculated
CONFIDENCE_IMAGE	2D image containing information about each pixel status.	Native
NORM_AMPLITUDE_IMAGE	The normalized amplitude image.	Native
RADIAL_DISTANCE_IMAGE	2D image containing the radial distance value for each pixel.	Native
RADIAL_DISTANCE_NOISE	2D image containing the distance noise value for each pixel.	Native
XYZ	The point cloud in Cartesian coordinates.	Calculated

Note

Even though the GRAYSCALE_IMAGE buffer is shown to be available in the O3X JSON configuration, no acquisition mode currently provides this buffer, so we have not included it in the list.

Data formats

ifm3d supports multiple devices. These devices support multiple buffers and data types which can have different data formats on different devices.

We recommend to retrieve the format of a specific buffer_id programmatically. One can use the code below (adapt to the specific buffer_id):

C++Python

ifm3d::Buffer xyz = frame->GetBuffer(ifm3d::buffer_id::XYZ);

// Query the data format and channel.
std::cout << xyz.nchannels() << std::endl;
std::cout << static_cast<int>(xyz.dataFormat()) << std::endl;

In C++, one has to refer to the pixel format correspondence defined below:

FORMAT_8U = 0,
FORMAT_8S = 1,
FORMAT_16U = 2,
FORMAT_16S = 3,
FORMAT_32U = 4,
FORMAT_32S = 5,
FORMAT_32F = 6,
FORMAT_64U = 7,
FORMAT_64F = 8,
FORMAT_16U2 = 9,
FORMAT_32F3 = 10

For instance, the format returned for ifm3d::buffer_id::XYZ is 2, which corresponds to FORMAT_32F (32 bit float).

See the full examples in the ifm3d-examples repository, in Python, and in C++.