OpenVX 1.1 Reference Guide

www.khronos.org/openvx©2016 Khronos Group - Rev. 0616
OpenVX 1.1 Quick Reference Guide Page 1
Vision Functions
Absolute Difference [3.2]
out(x, y) = |in1 (x, y) − in2 (x, y)|
vx_node vxAbsDiffNode (vx_graph graph, vx_image in1,
vx_image in2, vx_image out);
vx_status vxuAbsDiff (vx_context context, vx_image in1,
in1, in2, out: Image of VX_DF_IMAGE_U8 or VX_DF_IMAGE_S16 format.
Accumulate [3.3]
•accum(x, y) = accum(x, y) + input(x, y)
vx_node vxAccumulateImageNode (vx_graph graph,
vx_image input, vx_image accum);
vx_status vxuAccumulateImage (vx_context context,
vx_image input, vx_image accum);
input: The input image of VX_DF_IMAGE_U8 format.
accum: The accumulation image of VX_DF_IMAGE_S16 format.
Accumulate Squared [3.4]
•Accumulates a squared input image to an output image.
vx_node vxAccumulateSquareImageNode (vx_graph graph,
vx_image input, vx_scalar shift, vx_image accum);
vx_status vxuAccumulateSquareImage (vx_context context,
vx_image input, vx_scalar shift, vx_image accum);
shift: Shift amount of type VX_TYPE_UINT32 (0 ≤ shift ≤ 15).
accum: The accumulation image of VX_DF_IMAGE_S16 format.
Accumulate Weighted [3.5]
accum(x, y) = (1 − α) * accum(x, y) + α * input(x, y)
vx_node vxAccumulateWeightedImageNode (vx_graph graph,
vx_image input, vx_scalar alpha, vx_image accum);
vx_status vxuAccumulateWeightedImage (vx_context context,
vx_image input, vx_scalar alpha, vx_image accum);
alpha: The scale of type VX_TYPE_FLOAT32 (0.0 ≤ α ≤ 1.0).
accum: The accumulation image of VX_DF_IMAGE_U8 format.
Arithmetic Addition [3.6]
out(x, y) = in1 (x, y) + in2 (x, y)
vx_node vxAddNode (vx_graph graph, vx_image in1,
vx_image in2, vx_enum policy, vx_image out);
vx_status vxuAdd (vx_context context, vx_image in1,
in1, in2, out: Image of VX_DF_IMAGE_{U8, S16} format.
policy: VX_CONVERT_POLICY_{WRAP, SATURATE}.
Arithmetic Subtraction [3.7]
out(x, y) = in1 (x, y) − in2 (x, y)
vx_node vxSubtractNode (vx_graph graph, vx_image in1,
vx_status vxuSubtract (vx_context context, vx_image in1,
in1, in2, out: Image of VX_DF_IMAGE_{U8, S16} format.
Bitwise AND [3.8]
out(x, y) = in1 (x, y) ⋀ in2 (x, y)
vx_node vxAndNode (vx_graph graph, vx_image in1,
vx_status vxuAnd (vx_context context, vx_image in1,
in1, in2: The input image of VX_DF_IMAGE_U8 format.
out: The output image of VX_DF_IMAGE_U8 format.
Bitwise EXCLUSIVE OR [3.9]
out(x, y) = in1 (x, y) ⊕ in2 (x, y)
vx_node vxXorNode (vx_graph graph, vx_image in1,
vx_status vxuXor (vx_context context, vx_image in1,
Bitwise INCLUSIVE OR [3.10]
out(x, y) = in1 (x, y) ⋁ in2 (x, y)
vx_node vxOrNode (vx_graph graph, vx_image in1,
vx_status vxuOr (vx_context context, vx_image in1,
Bitwise NOT [3.11]
out(x, y) = in(x, y)
vx_node vxNotNode (vx_graph graph, vx_image input,
vx_image output);
vx_status vxuNot (vx_context context, vx_image input,
vx_image output);
input, output: Image of VX_DF_IMAGE_U8 format.
Box Filter [3.12]
Computes a Box filter over a window of the input image.
vx_node vxBox3x3Node (vx_graph graph, vx_image input,
vx_image output);
vx_status vxuBox3x3 (vx_context context, vx_image input,
vx_image output);
Canny Edge Detector [3.13]
Provides a Canny edge detector kernel.
vx_node vxCannyEdgeDetectorNode (vx_graph graph,
vx_image input, vx_threshold hyst, vx_int32 gradient_size,
vx_enum norm_type, vx_image output);
vx_status vxuCannyEdgeDetector (vx_context context,
vx_image input, vx_threshold hyst, vx_int32 gradient_size,
vx_enum norm_type, vx_image output);
hyst: The double threshold for hysteresis. VX_TYPE_{U8, U16}.
gradient_size: Size of Sobel filter window; supports at least 3, 5, 7.
norm_type: Norm used to compute the gradient. VX_NORM_{L1, L2}.
Channel Combine [3.14]
Combines multiple image planes.
vx_node vxChannelCombineNode (vx_graph graph,
vx_image plane0, vx_image plane1, vx_image plane2,
vx_image plane3, vx_image output);
vx_status vxuChannelCombine (vx_context context,
vx_image plane0, vx_image plane1, vx_image plane2,
vx_image plane3, vx_image output);
plane{0, 1}: Plane forming channel {0, 1}. VX_DF_IMAGE_U8.
plane{2, 3}: [Opt.] Plane that forms channel {2, 3}. VX_DF_IMAGE_U8.
output: The output image.
Channel Extract [3.15]
Extracts a plane from a multi-planar or interleaved image.
vx_node vxChannelExtractNode (vx_graph graph,
vx_image input, vx_enum channel, vx_image output);
vx_status vxuChannelExtract (vx_context context,
vx_image input, vx_enum channel, vx_image output);
input: One of the defined vx_df_image_e multi-channel formats.
channel: Channel to extract. VX_CHANNEL_{0, 1, 2, 3, R, G, B, A, Y, U, V}.
output: The output image of VX_DF_IMAGE_U8 format.
Color Convert [3.16]
Converts the format of an image.
vx_node vxColorConvertNode (vx_graph graph,
vx_image input, vx_image output);
vx_status vxuColorConvert (vx_context context,
input, output: The image {to, from} which to convert.
Convert Bit Depth [3.17]
•Converts image bit depth.
vx_node vxConvertDepthNode (vx_graph graph,
vx_image input, vx_image output, vx_enum policy,
vx_scalar shift);
vx_status vxuConvertDepth (vx_context context,
vx_image input, vx_image output, vx_enum policy,
vx_int32 shift);
input, output: The {input, output} image.
shift: The shift value of type VX_TYPE_INT32.
Custom Convolution [3.18]
•Convolves an image with a user-defined matrix.
vx_node vxConvolveNode (vx_graph graph, vx_image input,
vx_convolution conv, vx_image output);
vx_status vxuConvolve (vx_context context, vx_image input,
vx_convolution conv, vx_image output);
input: An input image of VX_DF_IMAGE_U8 format.
conv: The vx_int16 convolution matrix.
output: The output image of VX_DF_IMAGE_{S16, U8} format.
Dilate Image [3.19]
Grows the white space in a VX_DF_IMAGE_U8 Boolean image.
vx_node vxDilate3x3Node (vx_graph graph, vx_image input,
vx_image output);
vx_status vxuDilate3x3 (vx_context context, vx_image input,
vx_image output);
Equalize Histogram [3.20]
Normalizes brightness and contrast of a grayscale image.
vx_node vxEqualizeHistNode (vx_graph graph, vx_image input,
vx_image output);
vx_status vxuEqualizeHist (vx_context context, vx_image input,
vx_image output);
input, output: The grayscale image of VX_DF_IMAGE_U8 format.
Erode Image [3.21]
Shrinks the white space in a VX_DF_IMAGE_U8 Boolean image.
vx_node vxErode3x3Node (vx_graph graph, vx_image input,
vx_image output);
vx_status vxuErode3x3 (vx_context context, vx_image input,
vx_image output);
Fast Corners [3.22]
Finds corners in an image.
vx_node vxFastCornersNode (vx_graph graph, vx_image input,
vx_scalar strength_thresh, vx_bool nonmax_suppression,
vx_array corners, vx_scalar num_corners);
vx_status vxuFastCorners (vx_context context, vx_image input,
vx_scalar strength_thresh, vx_bool nonmax_suppression,
vx_array corners, vx_scalar num_corners);
strength_thresh: (VX_TYPE_FLOAT32) Intensity difference threshold.
nonmax_suppression: Boolean specifying if non-maximum suppression
is applied to detected corners before being placed in the vx_array.
corners: Output corner vx_array of type VX_TYPE_KEYPOINT.
num_corners: [Opt.] Number of detected corners in image. (VX_TYPE_SIZE)
(Continued on next page)
OpenVX (Open Computer Vision Acceleration API) is a low-level programming
framework domain to access computer vision hardware acceleration with both
functional and performance portability. OpenVX supports modern hardware
architectures, such as mobile and embedded SoCs as well as desktop systems.
[n.n] refers to sections in the OpenVX 1.1 specification available at khronos.org/registry/vx/
Parameter color coding: Output, Input, and Input/Output parameters.
Parameters marked as [Opt.] are optional. If omitted, NULL.
In descriptions, curly braces {} mean “one of,” and square braces [] mean “optional.”
•Indicates the overflow policy used is VX_CONVERT_POLICY_SATURATE.
•Refer to list of enumerations on page 7 of this reference guide.
OpenVX Functions and Objects
VX_API_CALL
In every OpenVX function and object, insert VX_API_CALL before the function name, as shown in
the example below. It was omitted from the functions on this reference card to save space.
<return_type> VX_API_CALL vxFunctionName(T arg1 , . . . , T argN);
Vision Functions
Vision functions in OpenVX may be graph mode or immediate mode.
• Graph mode functions have “Node” in the function name. They may be created and linked
together, verified by the implementation, then executed as often as needed.
• Immediate mode functions are executed on a context immediately, as if they were single
node graphs, with no leaking side-effects.
In the vision functions, the parameter graph is the reference to the graph, and the parameter
context is the reference to the overall context.

Vision Functions (cont.)
Gaussian Filter [3.23]
Computes a Gaussian filter over a window of the input image.
vx_node vxGaussian3x3Node (vx_graph graph,
vx_status vxuGaussian3x3 (vx_context context,
Non-linear Filter [3.24]
Computes a non-linear filter over a window of the input image.
vx_node vxNonLinearFilterNode (vx_graph graph,
vx_enum function, vx_image input,
vx_matrix mask, vx_image output);
vx_status vxuNonLinearFilter (vx_context context,
vx_enum function, vx_image input,
vx_matrix mask, vx_image output);
function: The non-linear function of type
VX_NONLINEAR_FILTER_{MEDIAN, MIN, MAX}.
mask: The mask to apply (See vxCreateMatrixFromPattern).
Harris Corners [3.25]
Computes the Harris Corners of an image.
vx_node vxHarrisCornersNode (vx_graph graph, vx_image input,
vx_scalar strength_thresh, vx_scalar min_distance,
vx_scalar sensitivity, vx_int32 gradient_size,
vx_int32 block_size, vx_array corners, vx_scalar num_corners);
vx_status vxuHarrisCorners (vx_context context, vx_image input,
vx_scalar strength_thresh, vx_scalar min_distance,
vx_scalar sensitivity, vx_int32 gradient_size,
vx_int32 block_size, vx_array corners, vx_scalar num_corners);
strength_thresh: The minimum threshold of type VX_TYPE_FLOAT32
with which to eliminate Harris corner scores.
min_distance: The radial Euclidean distance of type VX_TYPE_FLOAT32
for non-maximum suppression.
sensitivity: The scalar sensitivity threshold k of type VX_TYPE_FLOAT32.
gradient_size: The gradient window size to use on the input.
block_size: Block window size used to compute the Harris corner score.
corners: The array of objects of type VX_TYPE_KEYPOINT.
num_corners: [Opt.] Num. of detected corners in image. (VX_TYPE_SIZE)
Histogram [3.26]
Generates a distribution from an image.
vx_node vxHistogramNode (vx_graph graph, vx_image input,
vx_distribution distribution);
vx_status vxuHistogram (vx_context context, vx_image input,
vx_distribution distribution);
distribution: The output distribution.
Gaussian Image Pyramid [3.27]
Computes a Gaussian image pyramid using a 5x5 kernel.
vx_node vxGaussianPyramidNode (vx_graph graph,
vx_image input, vx_pyramid gaussian);
vx_status vxuGaussianPyramid (vx_context context,
vx_image input, vx_pyramid gaussian);
gaussian: The Gaussian pyramid of VX_DF_IMAGE_U8 format.
Laplacian Image Pyramid [3.28]
Computes a Laplacian Image Pyramid from an input image.
vx_node vxLaplacianPyramidNode (vx_graph graph,
vx_image input, vx_pyramid laplacian, vx_image output);
vx_status vxuLaplacianPyramid (vx_context context,
vx_image input, vx_pyramid laplacian, vx_image output);
laplacian: The Laplacian pyramid of VX_DF_IMAGE_S16 format.
output: The lowest-resolution image of VX_DF_IMAGE_S16 necessary
to reconstruct the input image from the pyramid.
Reconstruction from Laplacian Image Pyramid [3.29]
Reconstructs the original image from a Laplacian Image Pyramid.
vx_node vxLaplacianReconstructNode (vx_graph graph,
vx_pyramid laplacian, vx_image input, vx_image output);
vx_status vxLaplacianReconstruct (vx_context context,
vx_pyramid laplacian, vx_image input, vx_image output);
laplacian: The Laplacian pyramid of VX_DF_IMAGE_S16 format.
input: The lowest-resolution image of VX_DF_IMAGE_S16 format.
output: The image of VX_DF_IMAGE_U8 with the highest possible
resolution reconstructed from the pyramid.
Integral Image [3.30]
Computes the integral image of the input.
vx_node vxIntegralImageNode (vx_graph graph,
vx_status vxuIntegralImage (vx_context context,
Magnitude [3.31]
mag(x, y) = √ gradx (x, y)2 + grady (x, y)2
vx_node vxMagnitudeNode (vx_graph graph, vx_image grad_x,
vx_image grad_y, vx_image mag);
vx_status vxuMagnitude (vx_context context, vx_image grad_x,
vx_image grad_y, vx_image mag);
grad_{x, y}: The input {x, y} image of VX_DF_IMAGE_S16 format.
mag: The magnitude image of VX_DF_IMAGE_S16 format.
Mean and Standard Deviation [3.32]
Computes the mean and standard deviation of the input pixels.
vx_node vxMeanStdDevNode (vx_graph graph,
vx_image input, vx_scalar mean, vx_scalar stddev);
vx_status vxuMeanStdDev (vx_context context,
vx_image input, vx_float32 *mean, vx_float32 *stddev);
input: The input image. VX_DF_IMAGE_U8 is supported.
mean: Average pixel value of type VX_TYPE_FLOAT32.
stddev: Standard deviation of the pixel values of VX_TYPE_FLOAT32.
Median Filter [3.33]
Computes median values over a window of the input image.
vx_node vxMedian3x3Node (vx_graph graph,
vx_status vxuMedian3x3 (vx_context context,
Min, Max Location [3.34]
Locates the minima and maxima in an image.
vx_node vxMinMaxLocNode (vx_graph graph,
vx_image input, vx_scalar minVal, vx_scalar maxVal,
vx_array minLoc, vx_array maxLoc, vx_scalar minCount,
vx_scalar maxCount);
vx_status vxuMinMaxLoc (vx_context context,
vx_image input, vx_scalar minVal, vx_scalar maxVal,
vx_array minLoc, vx_array maxLoc, vx_scalar minCount,
vx_scalar maxCount);
input: The input image of VX_DF_IMAGE_{U8, S16} format.
{min, max}Val: The {min, max} value in the image.
{min, max}Loc: [Opt.] The {min, max} locations of type
VX_TYPE_COORDINATES2D.
{min, max}Count: [Opt.] The number of detected {mins, maxes} in
image. Type VX_TYPE_UINT32.
Optical Flow Pyramid (LK) [3.35]
Computes the optical flow between two pyramid images.
vx_node vxOpticalFlowPyrLKNode (vx_graph graph,
vx_pyramid old_images, vx_pyramid new_images,
vx_array old_points, vx_array new_points_estimates,
vx_array new_points, vx_enum termination,
vx_scalar epsilon, vx_scalar num_iterations,
vx_scalar use_initial_estimate, vx_size window_dimension);
vx_status vxuOpticalFlowPyrLK (vx_context context,
vx_pyramid old_images, vx_pyramid new_images,
vx_array old_points, vx_array new_points_estimates,
vx_array new_points, vx_enum termination,
vx_scalar epsilon, vx_scalar num_iterations,
vx_scalar use_initial_estimate, vx_size window_dimension);
{old, new}_images: The {old, new} image pyramid of VX_DF_IMAGE_U8.
old_points: Array of key points in a vx_array of VX_TYPE_KEYPOINT.
new_points_estimates: An array of estimation on what is the output key
points in a vx_array of type VX_TYPE_KEYPOINT.
new_points: Array of key points in vx_array of type VX_TYPE_KEYPOINT.
termination: VX_TERM_CRITERIA_{ITERATIONS, EPSILON, BOTH}.
epsilon: The vx_float32 error for terminating the algorithm.
num_iterations: The number of iterations of type VX_TYPE_UINT32.
use_initial_estimate: VX_TYPE_BOOL set to vx_false_e or vx_true_e.
window_dimension: The size of the window.
Phase [3.36]
φ = tan−1 (grady (x, y) / gradx (x, y) ) , 0 ≤ φ ≤ 255
vx_node vxPhaseNode (vx_graph graph,
vx_image grad_x, vx_image grad_y, vx_image output);
vx_status vxuPhase (vx_context context,
vx_image grad_x, vx_image grad_y, vx_image output);
grad_{x, y}: The input {x, y} image of VX_DF_IMAGE_S16 format.
output: The phase image of VX_DF_IMAGE_U8 format.
Pixel-wise Multiplication [3.37]
out(x, y) = in1 (x, y) in2 (x, y) scale
vx_node vxMultiplyNode (vx_graph graph, vx_image in1,
vx_image in2, vx_scalar scale, vx_enum overflow_policy,
vx_enum rounding_policy, vx_image out);
vx_status vxuMultiply (vx_context context, vx_image in1,
vx_image in2, vx_float32 scale, vx_enum overflow_policy,
vx_enum rounding_policy, vx_image out);
in{1, 2}, out: Image of VX_DF_IMAGE_{U8, S16} format.
rounding_policy: VX_ROUND_POLICY_TO_{ZERO, NEAREST_EVEN}.
overflow_policy: VX_CONVERT_POLICY_{WRAP, SATURATE}.
scale: A non-negative value of type VX_TYPE_FLOAT32.
Remap [3.38]
output(x, y) = input(mapx (x, y), mapy (x, y))
vx_node vxRemapNode (vx_graph graph, vx_image input,
vx_remap table, vx_enum policy, vx_image output);
vx_status vxuRemap (vx_context context, vx_image input,
vx_remap table, vx_enum policy, vx_image output);
input, output: Image of type VX_DF_IMAGE_U8.
table: The remap table object.
policy: An interpolation type.
VX_INTERPOLATION_{NEAREST_NEIGHBOR, BILINEAR}.
Scale Image [3.39]
vx_node vxScaleImageNode (vx_graph graph, vx_image src,
vx_image dst, vx_enum type);
vx_status vxuScaleImage (vx_context context, vx_image src,
vx_image dst, vx_enum type);
src, dst: The {source, destination} image of type VX_DF_IMAGE_U8.
type: An interpolation type.
Half Scale Gaussian [3.39]
Performs a Gaussian blur on an image then half-scales it.
vx_node vxHalfScaleGaussianNode (vx_graph graph,
vx_image input, vx_image output, vx_int32 kernel_size);
vx_status vxuHalfScaleGaussian (vx_context context,
vx_image input, vx_image output, vx_int32 kernel_size);
kernel_size: Gaussian filter input size. Supported values are 1, 3, and 5.
Sobel3x3 [3.40]
Sobel filter, produces X and Y output planes.
vx_node vxSobel3x3Node (vx_graph graph, vx_image input,
vx_image output_x, vx_image output_y);
vx_status vxuSobel3x3 (vx_context context, vx_image input,
vx_image output_x, vx_image output_y);
input: The input of VX_DF_IMAGE_U8 format.
output_{x, y}: [Opt.] The output gradient in the {x, y} direction of
VX_DF_IMAGE_S16 format.
Table Lookup [3.41]
Uses a LUT to convert pixel values.
vx_node vxTableLookupNode (vx_graph graph,
vx_image input, vx_lut lut, vx_image output);
vx_status vxuTableLookup (vx_context context,
vx_image input, vx_lut lut, vx_image output);
input: Image of VX_DF_IMAGE_{U8, S16} format.
lut: The LUT of type VX_DF_IMAGE_{U8, S16}.
output: Image of VX_DF_IMAGE_{U8, S16} format.
Thresholding [3.42]
Produces a Boolean image by thresholding the input image.
vx_node vxThresholdNode (vx_graph graph, vx_image input,
vx_threshold thresh, vx_image output);
vx_status vxuThreshold (vx_context context, vx_image input,
vx_threshold thresh, vx_image output);
output: The output Boolean image.
thresh: Thresholding object.
Warp Affine [3.43]
Performs an affine transform on an image.
vx_node vxWarpAffineNode (vx_graph graph, vx_image input,
vx_matrix matrix, vx_enum type, vx_image output);
vx_status vxuWarpAffine (vx_context context, vx_image input,
vx_matrix matrix, vx_enum type, vx_image output);
matrix: The affine matrix. Must be 2x3 of type VX_TYPE_FLOAT32.
type: The interpolation type.

Get Status [3.45.6]
Return status values from Object constructors if they fail.
vx_status vxGetStatus (vx_reference reference);
reference: The reference to check for construction errors.
Array Objects [3.51]
Attributes: enum vx_array_attribute_e:
VX_ARRAY_{ITEMTYPE, NUMITEMS, CAPACITY, ITEMSIZE}
Add items to the Array.
vx_status vxAddArrayItems (vx_array arr, vx_size count,
const void *ptr, vx_size stride);
arr: The reference to the array.
count: The total number of elements to insert.
ptr: Location from which to read the input values.
stride: The stride in bytes between elements.
Allows the application to copy a range from/into an array object.
ret vxCopyArrayRange (vx_array array, vx_size range_start,
vx_size range_end, vx_size user_stride, void *user_ptr,
vx_enum usage, vx_enum user_mem_type);
array: The reference to the source/destination array object.
range_start: The index of the first item of the array object to copy.
range_end: Index of item following last item of array object to copy.
user_stride: Number of bytes between the beginning of two
consecutive items in the user memory pointed by user_ptr.
user_ptr: Address of memory location to store the requested data, or
from where to get the data to store into the array object.
usage: Declares the effect of the copy with regard to the array
object. VX_READ_ONLY or VX_WRITE_ONLY.
user_mem_type: VX_MEMORY_TYPE_{NONE, HOST}.
Create a reference to an Array object.
vx_array vxCreateArray (vx_context context,
vx_enum item_type, vx_size capacity);
context: The reference to the overall Context.
item_type: The type of objects to hold.
capacity: The maximal number of items that the array can hold.
Creates an opaque reference to a virtual Array with no direct
user access.
vx_array vxCreateVirtualArray (vx_graph graph,
vx_enum item_type, vx_size capacity);
graph: The reference to the parent graph.
item_type: The type of objects to hold, or zero to indicate an
unspecified item type.
capacity: The maximal number of items that the array can hold, or zero
to indicate an unspecified capacity.
Gives the application direct access to a range of an array object.
vx_status vxMapArrayRange (vx_array array,
vx_size range_start, vx_size range_end,
vx_map_id *map_id, vx_size *stride, void *ptr,
vx_enum usage, vx_enum mem_type, vx_uint32 flags);
array: The array object that contains the range to map.
range_start: The index of the first item of the array object to map.
range_end: The index of the item following the last item of the array
object to map.
map_id: The address of a vx_map_id variable where the function
returns a map identifier.
stride: The address of a vx_size variable where the function returns the
memory layout of the mapped array range.
ptr: The address of a pointer that the function sets to the address
where the requested data can be accessed.
usage: VX_{READ, WRITE}_ONLY or VX_READ_AND_WRITE.
mem_type: VX_MEMORY_TYPE_{NONE, HOST}.
flags: VX_NOGAP_X.
Query the Array for some specific information.
vx_status vxQueryArray (vx_array arr, vx_enum attribute,
void *ptr, vx_size size);
arr: The Array to release.
attribute: An attribute from vx_array_attribute_e.
ptr: Location at which to store the result.
size: The size in bytes of the container to which ptr points.
Release a reference of an Array object.
vx_status vxReleaseArray (vx_array *arr);
Truncate an Array (remove items from the end).
vx_status vxTruncateArray (vx_array arr,
vx_size new_num_items);
new_num_items: The new number of items for the Array.
Unmap and commit potential changes to an array object range.
vx_status vxUnmapArrayRange (vx_array array,
vx_map_id map_id);
array: The reference to the array object to unmap.
map_id: The unique map identifier returned by vxMapArrayRange.
Object: Array (Advanced) [3.64]
Registers user-defined structures to the context.
vx_enum vxRegisterUserStruct (vx_context context,
vx_size size);
size: The size of user struct in bytes.
Vision Functions (cont.)
Warp Perspective [3.44]
Performs a perspective transform on an image.
vx_node vxWarpPerspectiveNode (vx_graph graph,
vx_image input, vx_matrix matrix, vx_enum type,
vx_image output);
vx_status vxuWarpPerspective (vx_context context,
vx_image input, vx_matrix matrix, vx_enum type,
vx_image output);
matrix: Perspective matrix. Must be 3x3 of type VX_TYPE_FLOAT32.
type: The interpolation type.
Context Objects [3.48]
Attributes: enum vx_context_attribute_e:
VX_CONTEXT_{VENDOR[_ID], UNIQUE_KERNELS, MODULES,
REFERENCES, IMPLEMENTATION, EXTENSIONS[_SIZE],
UNIQUE_KERNEL_TABLE, IMMEDIATE_BORDER[_POLICY],
{CONVOLUTION, NONLINEAR}_MAX_DIMENSION,
OPTICAL_FLOW_MAX_WINDOW_DIMENSION}
Create a vx_context.
vx_context vxCreateContext ();
Retrieve the context from any reference from within a context.
vx_context vxGetContext (vx_reference reference);
reference: The reference from which to extract the context.
Query the context for some specific information.
vx_status vxQueryContext (vx_context context,
vx_enum attribute, void *ptr, vx_size size);
attribute: Attribute to query of type vx_context_attribute_e.
ptr: Pointer to where to store the result.
size: Size of the container to which ptr points.
Release the OpenVX object context.
vx_status vxReleaseContext (vx_context *context);
Set an attribute on the context.
vx_status vxSetContextAttribute (vx_context context,
vx_enum attribute, const void *ptr, vx_size size);
attribute: Attribute to set of type vx_context_attribute_e.
ptr: Pointer to the data to which to set the attribute.
size: Size in bytes of the container to which ptr points.
Sets the default target of the immediate mode.
vx_status vxSetImmediateModeTarget (vx_context context,
vx_enum target_enum, const char *target_string);
context: The reference to the implementation context.
target_enum: Default immediate mode target enum to be set to
vx_context object. VX_TARGET_{ANY, STRING, VENDOR_BEGIN}.
target_string: The target name ASCII string.
Delay Objects [3.67]
Attributes: enum vx_delay_attribute_e: VX_DELAY_{TYPE, SLOTS}
Age the internal delay ring by one.
vx_status vxAgeDelay (vx_delay delay);
delay: The pointer to the delay object.
Create a Delay object.
vx_delay vxCreateDelay (vx_context context, vx_reference
exemplar, vx_size slots);
context: The reference to the system context.
exemplar: The exemplar object.
slots: The number of reference in the delay.
Retrieve a reference from a delay object.
vx_reference vxGetReferenceFromDelay (vx_delay delay,
vx_int32 index);
delay: The reference to the delay object.
index: The index into the delay from which to extract the reference.
Query a vx_delay object attribute.
vx_status vxQueryDelay (vx_delay delay, vx_enum attribute,
attribute: The attribute to query from VX_DELAY_{TYPE, SLOTS}.
ptr: The location at which to store the resulting value.
size: The size of the container to which ptr points.
Release a reference to a delay object.
vx_status vxReleaseDelay (vx_delay *delay);
Convolution Objects [3.52]
Attributes: enum vx_convolution_attribute_e:
VX_CONVOLUTION_{ROWS, COLUMNS, SCALE, SIZE}
Copy coefficients from/into a convolution object.
vx_status vxCopyConvolutionCoefficients (
vx_convolution conv, void *user_ptr, vx_enum usage,
vx_enum user_mem_type);
conv: The reference to the source/destination convolution object.
user_ptr: The address of the memory location at which to store the
coefficient data.
usage: VX_READ_ONLY or VX_WRITE_ONLY.
Create a reference to a convolution matrix object.
vx_convolution vxCreateConvolution (vx_context context,
vx_size columns, vx_size rows);
columns, rows: Must be odd and = 3 and less than
VX_CONTEXT_CONVOLUTION_MAX_DIMENSION.
Queries an attribute on the convolution matrix object.
vx_status vxQueryConvolution (vx_convolution conv,
vxQueryConvolution parameters:
conv: The convolution matrix object to set.
attribute: VX_CONVOLUTION_{ROWS, COLUMNS, SCALE, SIZE}.
size: The size in bytes of the container or data to which ptr points.
Release the reference to a convolution matrix.
vx_status vxReleaseConvolution (vx_convolution *conv);
conv: The pointer to the convolution matrix to release.
Set attributes on the convolution object.
vx_status vxSetConvolutionAttribute (vx_convolution conv,
conv: The coordinates object to set.
attribute: VX_CONVOLUTION_{ROWS, COLUMNS, SCALE, SIZE}.
ptr: The pointer to the value to which to set the attribute.
size: The size in bytes of the container or data to which ptr points.
Distribution Objects [3.53]
Attributes: enum vx_distribution_attribute_e:
VX_DISTRIBUTION_{DIMENSIONS, OFFSET, RANGE, BINS,
WINDOW, SIZE}
Allows the application to copy from/into a distribution object.
vx_status vxCopyDistribution (vx_distribution distribution,
void * user_ptr, vx_enum usage,
distribution: The reference to the source/destination distribution
object.
user_ptr: The address of the memory location to store or get the data.
Create a reference to a 1D Distribution.
vx_distribution vxCreateDistribution (vx_context context,
vx_size numBins, vx_int32 offset, vx_int32 range);
context: The reference to the overall context.
numBins: The number of bins in the distribution.
offset: The start offset into the range value.
range: Total number of consecutive values of the distribution interval.

Image Objects[3.54]
Attributes: enum vx_image_attribute_e: VX_IMAGE_{WIDTH, HEIGHT,
FORMAT, PLANES, SPACE, RANGE, SIZE, MEMORY_TYPE}
Computes size needed to retrieve an image patch from an image.
vx_size vxComputeImagePatchSize (vx_image image,
const vx_rectangle_t *rect, vx_uint32 plane_index);
image: The reference to the image from which to extract the patch.
rect: Coordinates. Must be 0 = start end = dimension.
plane_index: The plane index from which to get the data.
Copies a rectangular patch from/into an image object plane.
vx_status vxCopyImagePatch (vx_image image,
const vx_rectangle_t *image_rect,
vx_uint32 image_plane_index,
const vx_imagepatch_addressing_t *user_addr,
void *user_ptr, vx_enum usage,
image: The reference to the source/destination image object.
image_rect: The coordinates of the image patch.
image_plane_index: The plane index of the image object.
user_addr: The address of a structure describing the layout of the user
memory location pointed by user_ptr.
user_ptr: The address of the memory location to store or get the data.
Create an opaque reference to an image buffer.
vx_image vxCreateImage (vx_context context,
vx_uint32 width, vx_uint32 height, vx_df_image color);
width, height: The image {width, height} in pixels.
color: •The VX_DF_IMAGE (vx_df_image_e) code that represents the
format of the image and the color space.
Create a sub-image from a single plane channel of another image.
vx_image vxCreateImageFromChannel (vx_image img,
vx_enum channel);
img: The reference to the parent image.
channel: The channel. VX_CHANNEL_{0, 1, 2, 3, R, G, B, A, Y, U, V}.
Create a reference to an externally allocated image object.
vx_image vxCreateImageFromHandle (
vx_context context, vx_df_image color,
const vx_imagepatch_addressing_t addrs[ ],
void *const ptrs[ ], vx_enum memory_type);
color: •The VX_DF_IMAGE (vx_df_image_e) code that represents the
format of the image and the color space.
addrs[ ]: The array of image patch addressing structures that define
the dimension and stride of the array of pointers.
ptrs[ ]: The array of platform-defined references to each plane.
memory_type: VX_MEMORY_TYPE_{NONE, HOST}.
Create an image from another image given a rectangle.
vx_image vxCreateImageFromROI (vx_image img,
vx_rectangle_t *rect);
img: The reference to the parent image.
rect: The region of interest rectangle.
Create a reference to an image object that has a singular,
uniform value in all pixels.
vx_image vxCreateUniformImage (vx_context context,
vx_uint32 width, vx_uint32 height, vx_df_image color,
const vx_pixel_value_t *value);
color: •The VX_DF_IMAGE (vx_df_image_e) code that represents
the format of the image and the color space.
value: The pointer to the pixel value to which to set all pixels.
Create opaque reference to image buffer with no direct user
access.
vx_image vxCreateVirtualImage (vx_graph graph,
vx_uint32 width, vx_uint32 height, vx_df_image color);
color: •The VX_DF_IMAGE (vx_df_image_e) code that represents
the format of the image and color space. VX_DF_IMAGE_VIRT
means the format is unspecified.
Access a specific indexed pixel in an image patch.
void *vxFormatImagePatchAddress1d (void *ptr,
vx_uint32 index,
const vx_imagepatch_addressing_t *addr);
ptr: The base pointer.
index: The 0-based index of the pixel count in the patch.
addr: Pointer to addressing mode information.
Access a specific pixel at a 2d coordinate in an image patch.
void *vxFormatImagePatchAddress2d (void *ptr,
vx_uint32 x, vx_uint32 y,
const vx_imagepatch_addressing_t *addr);
ptr: The base pointer.
addr: Pointer to addressing mode information.
Retrieve the valid region of the image as a rectangle.
vx_status vxGetValidRegionImage (vx_image image,
vx_rectangle_t *rect);
image: The image from which to retrieve the valid region.
rect: The destination rectangle.
Gives the application direct access to a rectangular patch of
an image object plane.
vx_status vxMapImagePatch (vx_image image,
const vx_rectangle_t *rect, vx_uint32 plane_index,
vx_map_id *map_id,
vx_imagepatch_addressing_t * addr, void **ptr,
vx_enum usage, vx_enum mem_type, vx_uint32 flags);
vxMapImagePatch parameters:
image: Reference to the image object containing the patch to map.
rect: The coordinates of the image patch.
plane_index: The plane index of the image object to be accessed.
map_id: Address of a vx_map_id variable where function returns a
map identifier.
addr: Address of a structure describing memory layout of image
patch.
usage: Declares the access mode for image patch.
VX_{READ, WRITE}_ONLY or VX_READ_AND_WRITE.
mem_type: Type of image patch memory.
VX_MEMORY_TYPE_{NONE, HOST}.
flags: VX_NOGAP_X.
Retrieve various attributes of an image.
vx_status vxQueryImage (vx_image image,
image: The reference to the image to query.
attribute: The attribute to query. From vx_image_attribute_e.
ptr: The pointer to the location at which to store the result.
Release a reference to an image object.
vx_status vxReleaseImage (vx_image *image);
image: The reference to the image to release.
Set attributes on the image.
vx_status vxSetImageAttribute (vx_image image,
image: The reference to the image on which to set the attribute.
attribute: The attribute to set. From vx_image_attribute_e.
ptr: The pointer to the location from which to read the value.
Sets valid rectangle for image according to a supplied rectangle.
vx_status vxSetImageValidRectangle (vx_image image,
const vx_rectangle_t *rect);
image: The reference to the image.
rect: The value to be set to the image valid rectangle.
Create a reference to an externally allocated image object.
vx_status vxSwapImageHandle (vx_image image,
void *const new_ptrs[ ], void *prev_ptrs[ ],
vx_size num_planes);
image: The reference to the image created from handle.
new_ptrs[ ]: The pointer to a caller-owned array that contains the
new image handle.
prev_ptrs[ ]: The pointer to a caller-owned array in which the
application returns the previous image handle.
num_planes: Number of planes in the image.
Unmap and commit potential changes to an image object patch.
vx_status vxUnmapImagePatch (vx_image image,
vx_map_id map_id);
image: The reference to the image object to unmap.
map_id: The unique map identifier returned by vxMapImagePatch.
Graph Objects[3.49]
Attributes: enum vx_graph_attribute_e: VX_GRAPH_{NUMNODES,
PERFORMANCE, NUMPARAMETERS, STATE}
Create an empty graph.
vx_graph vxCreateGraph (vx_context context);
Returns a Boolean to indicate the state of graph verification.
vx_bool vxIsGraphVerified (vx_graph graph);
graph: The pointer to the graph to verify.
Cause the synchronous processing of a graph.
vx_status vxProcessGraph (vx_graph graph);
graph: The graph to execute.
Query attributes of the Graph.
vx_status vxQueryGraph (vx_graph graph,
graph: The reference to the created graph.
attribute: An attribute from vx_graph_attribute_e.
Register a delay for auto-aging.
vx_status vxRegisterAutoAging (vx_graph graph,
vx_delay delay);
graph: The graph to which the delay is registered for auto-aging.
delay: The delay to automatically age.
Release a reference to a graph.
vx_status vxReleaseGraph (vx_graph *graph);
graph: The pointer to the graph to release.
Schedule a graph for future execution.
vx_status vxScheduleGraph (vx_graph graph);
graph: The graph to schedule.
Allows the user to set attributes on the graph.
vx_status vxSetGraphAttribute (vx_graph graph,
graph: The reference to the created graph.
attribute: VX_GRAPH_{NUMNODES, PERFORMANCE,
NUMPARAMETERS, STATE}.
ptr: The location from which to read the value.
Verify the state of the graph before it is executed.
vx_status vxVerifyGraph (vx_graph graph);
graph: The reference to the graph to verify.
Wait for a specific graph to complete.
vx_status vxWaitGraph (vx_graph graph);
graph: The graph on which to wait.
Distribution Objects (cont.)
Allows application direct access to the distribution object.
vx_status vxMapDistribution (vx_distribution distribution,
vx_map_id *map_id, void *ptr, vx_enum usage,
vx_enum mem_type, vx_bitfield flags);
distribution: The reference to the distribution object to map.
map_id: Address of variable where function returns a map identifier.
ptr: Address of a pointer that the function sets to the address where
the requested data can be accessed.
usage: VX_READ_ONLY, VX_WRITE_ONLY, or VX_READ_AND_WRITE.
mem_type: VX_MEMORY_TYPE_{NONE, HOST}.
flags: Must be 0.
Query a Distribution object.
vx_status vxQueryDistribution (vx_distribution distribution,
distribution: Reference to the distribution.
attribute: Attribute to query. From vx_distribution_attribute_e.
ptr: The location at which to store the result.
Release a reference to a distribution object.
vx_status vxReleaseDistribution ( vx_distribution *distribution);
distribution: The reference to the distribution.
Set the Distribution back to the memory.
vx_status vxUnmapDistribution (
vx_distribution distribution, vx_map_id map_id);
distribution: The reference to the distribution object to unmap.
map_id: The unique map identifier that was returned when calling
vxMapDistribution.

ObjectArray Objects[3.61]
Attributes: enum vx_object_array_attribute_e:
VX_OBJECT_ARRAY_{ITEMTYPE, NUMITEMS}
Creates a reference to an ObjectArray of count objects.
vx_object_array vxCreateObjectArray (vx_context context,
vx_reference exemplar, vx_size count);
context: The reference to the overall Context.
exemplar: The exemplar object that defines the metadata of the
created objects in the ObjectArray.
count: The number of Objects to create in the ObjectArray.
Creates an opaque reference to a virtual ObjectArray.
vx_object_array vxCreateVirtualObjectArray (
vx_graph graph, vx_reference exemplar, vx_size count);
graph: The reference to the graph in which to create the
ObjectArray.
exemplar: The exemplar object that defines the type of object in
the ObjectArray.
count: The number of Objects to create in the ObjectArray.
Retrieves the reference to the OpenVX Object.
vx_reference vxGetObjectArrayItem (vx_object_array arr,
vx_uint32 index);
arr: The ObjectArray.
index: The index of the object in the ObjectArray.
Queries an attribute from the ObjectArray.
vx_status vxQueryObjectArray (vx_object_array arr,
arr: The reference to the ObjectArray.
attribute: VX_OBJECT_ARRAY_{ITEMTYPE, NUMITEMS}
Releases a reference of an ObjectArray Object.
vx_status vxReleaseObjectArray (vx_object_array *arr);
arr: The pointer to the ObjectArray to release.
ParameterObjects [3.69]
Attributes: enum vx_parameter_attribute_e:
VX_PARAMETER_{INDEX, DIRECTION, TYPE, STATE, REF}
Retrieve a vx_parameter from a vx_kernel.
vx_parameter vxGetKernelParameterByIndex (
vx_kernel kernel, vx_uint32 index);
kernel: The reference to the kernel.
index: The index of the parameter.
Retrieve a vx_parameter from a vx_node.
vx_parameter vxGetParameterByIndex (vx_node node,
vx_uint32 index);
node: The node from which to extract the parameter.
Query a parameter to determine its meta-information.
vx_status vxQueryParameter (vx_parameter param,
param: The reference to the parameter.
attribute: The attribute to query from vx_parameter_attribute_e.
Release a reference to a parameter object.
vx_status vxReleaseParameter (vx_parameter *param);
param: The pointer to the parameter.
Set the specified parameter data for a kernel on the node.
vx_status vxSetParameterByIndex (vx_node node,
vx_uint32 index, vx_reference value);
node: The node that contains the kernel.
value: The desired value of the parameter.
Associate parameter and data references with a kernel on a node.
vx_status vxSetParameterByReference (
vx_parameter parameter, vx_reference value);
parameter: The reference to the parameter.
value: The value to associate with the parameter.
NodeObjects [3.50]
Attributes: enum vx_node_attribute_e: VX_NODE_{STATUS,
PERFORMANCE, BORDER, LOCAL_DATA_{SIZE, PTR}, PARAMETERS,
IS_REPLICATED, REPLICATE_FLAGS, VALID_RECT_RESET}
Queries information out of a node.
vx_status vxQueryNode (vx_node node, vx_enum attribute,
node: The reference to the node to query.
attribute: The vx_node_attribute_e value to query.
Release a reference to a Node object.
vx_status vxReleaseNode (vx_node *node);
node: The reference of the node to release.
Remove a Node from its parent Graph and release it.
void vxRemoveNode (vx_node *node);
node: The reference to the node to remove.
Creates replicas of the same node to process a set of objects.
vx_status vxReplicateNode (vx_graph graph,
vx_node first_node, vx_bool replicate[ ],
vx_uint32 number_of_parameters);
graph: The reference to the graph.
first_node: The reference to the graph node to replicate.
replicate[ ]: An array indicating the parameters to replicate.
number_of_parameters: Number of elements in the replicate array.
Set attributes of a node before Graph Validation.
vx_status vxSetNodeAttribute (vx_node node,
node: The reference to the node.
attribute: The vx_node_attribute_e value to set.
ptr: Pointer to desired value of the attribute.
size: The size in bytes of the objects to which ptr points.
Set attributes of a node before Graph Validation.
vx_status vxSetNodeTarget (vx_node node,
vx_enum target_enum, const char *target_string);
node: The reference to the vx_node object.
target_enum: The target enum to be set to the vx_node object.
VX_TARGET_{ANY, STRING, VENDOR_BEGIN}.
target_string: The target name ASCII string.
Object: Node (Advanced) [3.65]
Defines the advanced features of the Node Interface.
vx_node vxCreateGenericNode (vx_graph graph,
vx_kernel kernel);
graph: The reference to the graph in which this node exists.
kernel: The kernel reference to associate with this new node.
Matrix Objects[3.56]
Attributes: enum vx_matrix_attribute_e:
VX_MATRIX_{TYPE, ROWS, COLUMNS, SIZE, ORIGIN, PATTERN}
Copy from or to a matrix data.
vx_status vxCopyMatrix (vx_matrix matrix, void *user_ptr,
matrix: The reference to the source/destination matrix object.
user_ptr: The address of the memory location for storage or
retrieval.
Creates a reference to a matrix object.
vx_matrix vxCreateMatrix (vx_context c,
vx_enum data_type, vx_size columns, vx_size rows);
vxCreateMatrix parameters:
c: The reference to the overall context.
data_type: Unit format of matrix. VX_TYPE_{UINT8, INT32, FLOAT32}.
columns: The first dimension.
rows: The second dimension.
Creates a reference to a matrix object from a Boolean pattern.
vx_matrix vxCreateMatrixFromPattern (vx_context c,
vx_enum pattern, vx_size columns, vx_size rows);
pattern: From vx_matrix_attribute_e.
columns: The first dimension.
rows: The second dimension.
Queries an attribute on the matrix object.
vx_status vxQueryMatrix (vx_matrix mat, vx_enum
attribute, void *ptr, vx_size size);
mat: The reference to the matrix.
attribute: The attribute to query. From vx_matrix_attribute_e.
Releases a reference to a matrix object.
vx_status vxReleaseMatrix (vx_matrix *mat);
mat: The reference to the matrix.
LUT Objects[3.55]
Attributes: enum vx_lut_attribute_e:
VX_LUT_{TYPE, COUNT, SIZE, OFFSET}
Allows the application to copy from/into a LUT object.
vx_status vxCopyLUT (vx_lut lut, void *user_ptr,
lut: The reference to the source/destination LUT object.
user_ptr: The address of the memory location to store or get data.
Create LUT object of a given type.
vx_lut vxCreateLUT (vx_context context, vx_enum data_type,
vx_size count);
context: The reference to the context.
data_type: The type of data stored in the LUT.
count: The number of entries desired.
vx_status vxMapLUT (vx_lut lut, vx_map_id *map_id,
void **ptr, vx_enum usage, vx_enum mem_type,
vx_bitfield flags);
lut: The reference to the LUT object to map.
map_id: Address where the function returns a map identifier.
usage: Declares the access mode for the LUT.
VX_{READ, WRITE}_ONLY or VX_READ_AND_WRITE.
mem_type: Specifies the type of the memory where the LUT is
requested to be mapped. VX_MEMORY_TYPE_{NONE, HOST}.
flags: Must be 0.
Query attributes from a LUT.
vx_status vxQueryLUT (vx_lut lut, vx_enum attribute,
lut: The LUT to query.
attribute: Attribute to query. From vx_lut_attribute_e.
Release a reference to a LUT object.
vx_status vxReleaseLUT (vx_lut *lut);
lut: The pointer to the LUT to release.
vx_status vxUnmapLUT (vx_lut lut, vx_map_id map_id);
lut: The reference to the LUT object to unmap.
map_id: The unique map identifier returned by vxMapLUT.
Kernel Objects[3.68]
Attributes: enum vx_kernel_attribute_e:
VX_KERNEL_{PARAMETERS, NAME, ENUM, LOCAL_DATA_SIZE}
Obtain a reference to kernel using vx_kernel_e enumeration.
vx_kernel vxGetKernelByEnum (vx_context context,
vx_enum kernel);
kernel: •Value from vx_kernel_e or vendor or client-defined value.
Obtain a reference to a kernel using a string to specify the
name.
vx_kernel vxGetKernelByName (vx_context context,
const vx_char *name);
name: The string of the name of the kernel to get.
Query the kernel to get information about the number of
parameters, enum values, etc.
vx_status vxQueryKernel (vx_kernel kernel,
kernel: The kernel reference to query.
attribute: The attribute to query. From vx_kernel_attribute_e.
Release the reference to the kernel.
vx_status vxReleaseKernel (vx_kernel *kernel);
kernel: The pointer to the kernel reference to release.

Hints [3.74]
Provide a generic API to give platform-specific hints.
vx_status vxHint (vx_reference reference, vx_enum hint,
const void *data, vx_size data_size);
reference: The reference to the object to hint at.
hint: •See vx_hint_e.
data: Optional vendor specific data.
data_size: Size of the data structure data.
Directives [3.75]
Provide a generic API to give platform-specific directives.
vx_status vxDirective (vx_reference reference,
vx_enum directive);
reference: The reference to the object to set the directive on.
directive: •The directive to set. See vx_directive_e.
User Kernels [3.76]
Set the signatures of the custom kernel.
vx_status vxAddParameterToKernel (vx_kernel kernel,
vx_uint32 index, vx_enum dir, vx_enum data_type,
vx_enum state);
index: The index of the parameter to add.
dir: VX_INPUT or VX_OUTPUT.
data_type: •Type of parameter, from vx_type_e (on page 8).
state: •Parameter state. See vx_parameter_state_e.
Advanced Framework
Node Callbacks [3.71]
Assign a callback to a node.
vx_status vxAssignNodeCallback (vx_node node,
vx_nodecomplete_f callback);
callback: Callback function pointer.
Retrieve the current node callback function pointer.
vx_nodecomplete_f vxRetrieveNodeCallback (vx_node node);
Callback prototype.
typedef vxAction(*vx_nodecomplete_f )(vx_node node);
node: The reference to the vx_node object.
Log [3.73]
Add a line to the log.
void vxAddLogEntry (vx_reference ref, vx_status status,
const char *message, ...);
ref: The reference to add the log entry against.
status: The status code. VX_SUCCESS status entries are ignored.
message: The human readable message to add to the log.
Register a callback facility to receive error logs.
void vxRegisterLogCallback (vx_context context,
vx_log_callback_f callback, vx_bool reentrant);
context: The overall context to OpenVX.
callback: The callback function or NULL.
reentrant: Boolean reentrancy flag indicating whether the callback
may be entered from multiple simultaneous tasks or threads.
Callback prototype for vxRegisterLogCallback.
typedef void (*vx_log_callback_f) (vx_context context,
vx_reference ref, vx_status status, vx_char string[ ]);
context: The overall context to OpenVX.
ref: The reference to add the log entry against.
status: The status code.
ScalarObjects [3.59]
Attribute: enum vx_scalar_attribute_e: VX_SCALAR_TYPE
Allows the application to copy from/into a scalar object.
vx_status vxCopyScalar(vx_scalar scalar, void *user_ptr,
scalar: The reference to the source/destination scalar object.
user_ptr: Address of the memory location where to store the
requested data, or from where to get the data to store into the
scalar object.
user_mem_type: Type of the memory referenced by the user_addr.
VX_MEMORY_TYPE_{NONE, HOST}.
Create a reference to a scalar object.
vx_scalar vxCreateScalar (vx_context context,
vx_enum data_type, const void *ptr);
context: The reference to the system context.
data_type: •The type of the scalar, from vx_type_e (on page 8).
ptr: Pointer to the initial value of the scalar.
Query attributes from a scalar.
vx_status vxQueryScalar (vx_scalar scalar,
scalar: The scalar object.
attribute: VX_SCALAR_TYPE.
ptr: Location at which to store the result.
Gets the scalar value out of a reference.
vx_status vxReadScalarValue (vx_scalar ref, void *ptr);
ref: The reference from which to get the scalar value.
ptr: A pointer to a location to which to copy the scalar value.
Release a reference to a scalar object.
vx_status vxReleaseScalar (vx_scalar *scalar);
scalar: The pointer to the scalar to release.
Sets the scalar value in a reference.
vx_status vxWriteScalarValue (vx_scalar ref, const void *ptr);
ref: The reference to which to set the scalar value.
ptr: A pointer to a location from where to copy the scalar value.
Reference Objects [3.47]
Attributes: enum vx_reference_attribute_e:
VX_REF_ATTRIBUTE_{COUNT, TYPE, NAME}
Query any reference type for basic information (count, type).
vx_status vxQueryReference (vx_reference ref,
ref: Reference to the object to query.
attribute: The value to query.
VX_REF_ATTRIBUTE_{COUNT, TYPE, NAME}
Release a reference.
vx_status vxReleaseReference (vx_reference *ref_ptr);
ref_ptr: The pointer to the reference of the object to release.
Increments the reference counter of an object.
vx_status vxRetainReference (vx_reference ref);
ref: The reference to retain.
Name a reference.
vx_status vxSetReferenceName (vx_reference ref,
const vx_char *name);
ref: The reference to the object to be named.
name: NULL if not named, or a pointer to NUL-terminated name.
RemapObjects [3.58]
Attributes: enum vx_remap_attribute_e: VX_REMAP_
{SOURCE_{WIDTH, HEIGHT}, DESTINATION_{WIDTH, HEIGHT}}
Create a remap table object.
vx_remap vxCreateRemap (vx_context context,
vx_uint32 src_width, vx_uint32 src_height,
vx_uint32 dst_width, vx_uint32 dst_height);
src_{width, height}: The {width, height} of the source image in pixels.
dst_{width, height}: The {width, height} of destination image in pixels.
Retrieve the source pixel point from a destination pixel.
vx_status vxGetRemapPoint (vx_remap table, vx_uint32 dst_x,
vx_uint32 dst_y, vx_float32 *src_x, vx_float32 *src_y);
table: Remap table reference.
dst_{x, y}: The destination {x, y} coordinate.
src_{x, y}: Pointer to location where to store the source coordinates in
float representation to allow interpolation.
Query attributes from a remap table.
vx_status vxQueryRemap (vx_remap r, vx_enum attribute,
r: The remap to query.
attribute: An attribute from vx_remap_attribute_e.
Release a reference to a remap table object.
vx_status vxReleaseRemap (vx_remap *table);
table: A pointer to the remap table to release.
Assign a destination pixel mapping to the source pixel.
vx_status vxSetRemapPoint (vx_remap table, vx_uint32 dst_x,
vx_uint32 dst_y, vx_float32 src_x, vx_float32 src_y);
table: Remap table reference.
dst_{x, y}: The destination {x, y} coordinate.
src_{x, y}: The source {x, y} coordinate in float to allow interpolation.
ThresholdObjects [3.60]
Attributes: enum vx_threshold_attribute_e:
VX_REMAP_{TYPE, THRESHOLD_{VALUE, LOWER, UPPER},
TRUE_VALUE, FALSE_VALUE, DATA_TYPE}
Create a reference to a threshold object of a given type.
vx_threshold vxCreateThreshold (vx_context c,
vx_enum thresh_type, vx_enum data_type);
thresh_type: The type of threshold to create.
data_type: The data type of the threshold’s value(s).
Query an attribute on the threshold object.
vx_status vxQueryThreshold (vx_threshold thresh,
thresh: Threshold object to query.
attribute: The attribute to modify from vx_threshold_attribute_e.
ptr: The location at which to store the result.
size: The size of the container pointed to by ptr.
Release a reference to a threshold object.
vx_status vxReleaseThreshold (vx_threshold *thresh);
thresh: A pointer to a threshold object to release.
Set attributes on the threshold object.
vx_status vxSetThresholdAttribute (vx_threshold thresh,
thresh: Threshold object to set.
attribute: The attribute to modify from vx_threshold_attribute_e.
ptr: The pointer to the value to which to set the attribute.
size: The size of the data pointed to by ptr.
Pyramid Objects[3.57]
Attributes: enum vx_pyramid_attribute_e:
VX_PYRAMID_{LEVELS, SCALE, WIDTH, HEIGHT, FORMAT}
Create a reference to a pyramid object.
vx_pyramid vxCreatePyramid (vx_context context,
vx_size levels, vx_float32 scale, vx_uint32 width,
vx_uint32 height, vx_df_image format);
levels: The number of levels desired.
scale: This must be a non-zero positive value.
width: The width of the 0th-level image in pixels.
height: The height of the 0th-level image in pixels.
format: Format of all images in the pyramid or VX_DF_IMAGE_VIRT.
Create a reference to a virtual pyramid object.
vx_pyramid vxCreateVirtualPyramid (vx_graph graph,
vx_size levels, vx_float32 scale, vx_uint32 width,
vx_uint32 height, vx_df_image format);
levels: The number of levels desired.
scale: This must be a non-zero positive value.
width: The width of the 0th-level image in pixels.
height: The height of the 0th-level image in pixels.
format: Format of all images in the pyramid or VX_DF_IMAGE_VIRT.
Retrieve a level of the pyramid as a vx_image.
vx_image vxGetPyramidLevel (vx_pyramid pyr,
vx_uint32 index);
pyr: The pointer to the pyramid.
index: The index of the level, such that index is less than levels.
Query an attribute from an image pyramid.
vx_status vxQueryPyramid (vx_pyramid pyr,
pyr: The pointer to the pyramid to query.
attribute: The attribute to query from vx_pyramid_attribute_e.
Release a reference to a pyramid object.
vx_status vxReleasePyramid (vx_pyramid *pyr);
pyr: The pointer to the pyramid to release.

Advanced Framework (cont.)
Allows users to add custom kernels to the known kernel database.
vx_kernel vxAddUserKernel (vx_context context,
const vx_char name[VX_MAX_KERNEL_NAME],
vx_enum enumeration, vx_kernel_f func_ptr,
vx_uint32 numParams, vx_kernel_validate_f validate,
vx_kernel_initialize_f init, vx_kernel_deinitialize_f deinit);
name: The string to use to match the kernel.
enumeration: Enumerated value of the kernel to be used by clients.
func_ptr: The process-local function pointer to be invoked.
numParams: The number of parameters for this kernel.
validate: The pointer to vx_kernel_validate_f, which validates
parameters to this kernel.
init, deinit: The kernel {initialization, deinitialization} function.
Allocates/registers user-defined kernel enumeration to a context.
vx_status vxAllocateUserKernelId (vx_context context,
vx_enum *pKernelEnumId);
pKernelEnumId: The pointer to return vx_enum for user-defined kernel.
Allocates/registers user-defined kernel library ID to a context.
vx_status vxAllocateUserKernelLibraryId (vx_context context,
vx_enum *pLibraryId);
pLibraryId: The pointer to vx_enum for user-kernel libraryId.
Called after parameters have been added and kernel is ready.
vx_status vxFinalizeKernel (vx_kernel kernel);
Load one or more kernels into the OpenVX context.
vx_status vxLoadKernels (vx_context context,
const vx_char *module);
module: The short name of the module to load.
Remove a vx_kernel from the vx_context.
vx_status vxRemoveKernel (vx_kernel kernel);
Set kernel attributes.
vx_status vxSetKernelAttribute (vx_kernel kernel,
attribute: The attribute to set, from vx_kernel_attribute_e.
(VX_KERNEL_{PARAMETERS, NAME, ENUM, LOCAL_DATA_SIZE})
ptr: Pointer to the attribute.
Set the attributes of a vx_meta_format object.
vx_status vxSetMetaFormatAttribute (vx_meta_format meta,
meta: The reference to the vx_meta_format object to set.
attribute: Use the subset of data object attributes that define the meta
data of this object or attributes from vx_meta_format_attribute_e.
ptr: The input pointer of the value to set on the meta format object.
Set the attributes of a vx_meta_format object.
vx_status vxSetMetaFormatFromReference (
vx_meta_format meta, vx_reference exemplar);
meta: The meta format object to set.
exemplar: The exemplar data object.
Unload one or more kernels from the module.
vx_status vxUnloadKernels (vx_context context,
const vx_char *module);
module: The short name of the module to unload.
Graph Parameters [3.77]
Add the given parameter extracted from a vx_node to the graph.
vx_status vxAddParameterToGraph (vx_graph graph,
vx_parameter parameter);
graph: The graph reference.
parameter: Parameter reference to add to the graph from the node.
Retrieve a vx_parameter from a vx_graph.
vx_parameter vxGetGraphParameterByIndex (
vx_graph graph, vx_uint32 index);
index: The parameter index.
Set a reference to the parameter on the graph.
vx_status vxSetGraphParameterByIndex (vx_graph graph,
vx_uint32 index, vx_reference value);
index: The parameter index.
value: The reference to set to the parameter.
Enumerators
vx_enum_e
VX_ENUM_ACCESSOR vx_accessor_e
VX_ENUM_ACTION vx_action_e
VX_ENUM_BORDER vx_border_e
VX_ENUM_BORDER_POLICY vx_border_policy_e
VX_ENUM_CHANNEL vx_channel_e
VX_ENUM_COLOR_RANGE vx_channel_range_e
VX_ENUM_COLOR_SPACE vx_color_space_e
VX_ENUM_CONVERT_POLICY vx_convert_policy_e
VX_ENUM_DIRECTION vx_direction_e
VX_ENUM_DIRECTIVE vx_directive_e
VX_ENUM_GRAPH_STATE vx_graph_state_e
VX_ENUM_HINT vx_hint_e
VX_ENUM_INTERPOLATION vx_interpolation_type_e
VX_ENUM_MEMORY_TYPE vx_memory_type_e
VX_ENUM_NONLINEAR vx_non_linear_filter_e
VX_ENUM_NORM_TYPE vx_norm_type_e
VX_ENUM_PARAMETER_STATE vx_parameter_state_e
VX_ENUM_PATTERN vx_pattern_e
VX_ENUM_ROUND_POLICY vx_round_policy_e
VX_ENUM_TARGET vx_target_e
VX_ENUM_TERM_CRITERIA vx_termination_criteria_e
VX_ENUM_THRESHOLD_TYPE vx_threshold_type_e
vx_accessor_e
VX_{READ, WRITE}_ONLY
VX_READ_AND_WRITE
vx_action_e
VX_ACTION_{CONTINUE, ABANDON}
vx_border_e
VX_BORDER_{UNDEFINED, CONSTANT, REPLICATE}
vx_border_policy_e
VX_BORDER_POLICY_DEFAULT_TO_UNDEFINED
VX_BORDER_POLICY_RETURN_ERROR
vx_channel_e
VX_CHANNEL_{0, 1, 2, 3}
VX_CHANNEL_{R, G, B, A}
VX_CHANNEL_{Y, U , V}
vx_channel_range_e
VX_CHANNEL_RANGE_{FULL, RESTRICTED}
vx_color_space_e
VX_COLOR_SPACE_{NONE, DEFAULT}
VX_COLOR_SPACE_BT601_{525, 625}
VX_COLOR_SPACE_BT709
vx_convert_policy_e
VX_CONVERT_POLICY_{WRAP, SATURATE}
vx_df_image_e
VX_DF_IMAGE_VIRT
VX_DF_IMAGE_RGB
VX_DF_IMAGE_RGBX
VX_DF_IMAGE_NV12
VX_DF_IMAGE_NV21
VX_DF_IMAGE_UYVY
VX_DF_IMAGE_YUYV
VX_DF_IMAGE_IYUV
VX_DF_IMAGE_YUV4
VX_DF_IMAGE_U8
VX_DF_IMAGE_U16
VX_DF_IMAGE_S16
VX_DF_IMAGE_U32
VX_DF_IMAGE_S32
vx_direction_e
VX_INPUT, VX_OUTPUT, VX_BIDIRECTIONAL
vx_directive_e
VX_DIRECTIVE_{DISABLE, ENABLE}_LOGGING
VX_DIRECTIVE_{DISABLE, ENABLE}_PERFORMANCE
vx_graph_state_e
VX_GRAPH_STATE_{UNVERIFIED, VERIFIED}
VX_GRAPH_STATE_{RUNNING, ABANDONED, COMPLETED}
vx_hint_e
VX_HINT_PERFORMANCE_DEFAULT
VX_HINT_PERFORMANCE_LOW_POWER
VX_HINT_PERFORMANCE_HIGH_SPEED
vx_interpolation_type_e
VX_INTERPOLATION_NEAREST_NEIGHBOR
VX_INTERPOLATION_BILINEAR
VX_INTERPOLATION_AREA
vx_map_flag_e
VX_NOGAP_X
vx_memory_type_e
VX_MEMORY_TYPE_NONE
VX_MEMORY_TYPE_ HOST
vx_non_linear_filter_e
VX_NONLINEAR_FILTER_MEDIAN
VX_NONLINEAR_FILTER_MIN
VX_NONLINEAR_FILTER_ MAX
vx_norm_type_e
VX_NORM_{L1, L2}
vx_parameter_state_e
VX_PARAMETER_STATE_REQUIRED
VX_PARAMETER_STATE_OPTIONAL
vx_pattern_e
VX_PATTERN_BOX
VX_PATTERN_CROSS
VX_PATTERN_DISK
VX_PATTERN_OTHER
vx_round_policy_e
VX_ROUND_POLICY_TO_ZERO
VX_ROUND_POLICY_TO_NEAREST_EVEN
vx_status_e
VX_STATUS_MIN
VX_ERROR_REFERENCE_NONZERO
VX_ERROR_MULTIPLE_WRITERS
VX_ERROR_GRAPH_ABANDONED
VX_ERROR_GRAPH_SCHEDULED
VX_ERROR_INVALID_{SCOPE, NODE, GRAPH, TYPE, VALUE,
DIMENSION, FORMAT, LINK, REFERENCE, MODULE,
PARAMETERS}
VX_ERROR_OPTIMIZED_AWAY
VX_ERROR_NO_MEMORY
VX_ERROR_NO_RESOURCES
VX_ERROR_NOT_COMPATIBLE
VX_ERROR_NOT_ ALLOCATED
VX_ERROR_NOT_ SUFFICIENT
VX_ERROR_NOT_ SUPPORTED
VX_ERROR_NOT_ IMPLEMENTED
VX_FAILURE
VX_SUCCESS
vx_target_e
VX_TARGET_ANY
VX_TARGET_STRING
VX_TARGET_VENDOR_BEGIN
vx_termination_criteria_e
VX_TERM_CRITERIA_ITERATIONS
VX_TERM_CRITERIA_EPSILON
VX_TERM_CRITERIA_BOTH
vx_threshold_type_e
VX_THRESHOLD_TYPE_BINARY
VX_THRESHOLD_TYPE_ RANGE

Macros [3.45.3]
Defines the major version number macro.
#define VX_VERSION_MAJOR( x ) ((x 0xFF) 8)
Defines the minor version number macro.
#define VX_VERSION_MINOR( x ) ((x 0xFF) 0)
Defines the OpenVX Version Number.
#define VX_VERSION VX_VERSION_1_1
A type mask removes the scalar/object type from the attribute.
#define VX_TYPE_MASK (0x000FFF00)
Converts a set of four chars into a uint32_t container of a VX_DF_IMAGE code.
#define VX_DF_IMAGE( a, b, c, d ) ((a) | (b 8) | (c 16) | (d 24))
Defines the manner in which to combine the Vendor and Object IDs to get the base value of the
enumeration.
#define VX_ENUM_BASE( vendor, id ) (((vendor) 20) | (id 12))
Use to aid in debugging values in OpenVX.
#define VX_FMT_REF “%p”
Use to aid in debugging values in OpenVX.
#define VX_FMT_SIZE “%zu”
Use to indicate the 1:1 ratio in Q22.10 format.
#define VX_SCALE_UNITY (1024u)
OpenVX is a trademark of the Khronos Group. The Khronos Group is an industry consortium
creating open standards for the authoring and acceleration of parallel computing, graphics, and
dynamic media, and more on a wide variety of platforms and devices.
See www.khronos.org to learn more about the Khronos Group.
See www.khronos.org/openvx to learn more about OpenVX.
Image Access Example [2.15.2]
vx_status status = VX_SUCCESS;
void *base_ptr = NULL;
vx_uint32 width = 640, height = 480, plane = 0;
vx_image image = vxCreateImage(context, width, height, VX_DF_IMAGE_U8);
vx_rectangle_t rect;
vx_imagepatch_addressing_t addr;
rect.start_x = rect.start_y = 0;
rect.end_x = rect.end_y = PATCH_DIM;
status = vxAccessImagePatch(image, rect, plane,addr,
base_ptr, VX_READ_AND_WRITE);
if (status == VX_SUCCESS)
{
vx_uint32 x,y,i,j;
vx_uint8 pixel = 0;
/* addressing options */
/* use linear addressing function/macro */
for (i = 0; i addr.dim_x*addr.dim_y; i++) {
vx_uint8 *ptr2 = vxFormatImagePatchAddress1d(base_ptr, i, addr);
*ptr2 = pixel;
}
/* 2d addressing option */
for (y = 0; y addr.dim_y; y+=addr.step_y) {
for (x = 0; x addr.dim_x; x+=addr.step_x) {
vx_uint8 *ptr2 = vxFormatImagePatchAddress2d(base_ptr, x, y, addr);
*ptr2 = pixel;
}
}
/* direct addressing by client. for subsampled planes, scale will change. */
for (y = 0; y addr.dim_y; y+=addr.step_y) {
j = (addr.stride_y*y*addr.scale_y)/VX_SCALE_UNITY;
for (x = 0; x addr.dim_x; x+=addr.step_x) {
vx_uint8 *tmp = (vx_uint8 *)base_ptr;
i = j + (addr.stride_x*x*addr.scale_x) / VX_SCALE_UNITY;
tmp[i] = pixel;
}
}
/* commits the data back to the image. If rect were 0 or empty, it would just decrement
* the reference (used when reading an image only).
*/
status = vxCommitImagePatch(image, rect, plane, addr, base_ptr);
}
vxReleaseImage(image);
OpenVX Types (vx_type_e) [3.45.5]
VX_TYPE_INVALID Invalid type value.
VX_TYPE_CHAR vx_char
VX_TYPE_INT8 vx_int8
VX_TYPE_UINT8 vx_uint8
VX_TYPE_FLOAT32 vx_float32
VX_TYPE_FLOAT64 vx_float64
VX_TYPE_ENUM vx_enum
VX_TYPE_SIZE vx_size
VX_TYPE_DF_IMAGE vx_df_image
VX_TYPE_BOOL vx_bool
VX_TYPE_SCALAR_MAX
Floating value for comparison between OpenVX scalars
and OpenVX structs.
VX_TYPE_RECTANGLE vx_rectangle_t
VX_TYPE_KEYPOINT vx_keypoint_t
VX_TYPE_COORDINATES2D vx_coordinates2d_t
VX_TYPE_COORDINATES3D vx_coordinates3d_t
VX_TYPE_USER_STRUCT_START User-defined struct base index.
VX_TYPE_VENDOR_STRUCT_START Vendor-defined struct base index.
VX_TYPE_KHRONOS_OBJECT_START Khronos-defined object base index.
VX_TYPE_VENDOR_OBJECT_START Vendor-defined object base index.
VX_TYPE_KHRONOS_STRUCT_MAX Value for comparison between Khronos-defined
structs and user structs.
VX_TYPE_USER_STRUCT_END
Value for comparison between user structs and vendor
structs.
VX_TYPE_VENDOR_STRUCT_END
Value for comparison between vendor structs and
Khronos-defined objects.
VX_TYPE_KHRONOS_OBJECT_END
Value for comparison between Khronos-defined
objects and vendor structs.
VX_TYPE_VENDOR_OBJECT_END Value used for bound checking of vendor objects.
VX_TYPE_REFERENCE vx_reference
VX_TYPE_CONTEXT vx_context
VX_TYPE_GRAPH vx_graph
VX_TYPE_NODE vx_node
VX_TYPE_KERNEL vx_kernel
VX_TYPE_PARAMETER vx_parameter
VX_TYPE_DELAY vx_delay
VX_TYPE_LUT vx_lut
VX_TYPE_DISTRIBUTION vx_distribution
VX_TYPE_PYRAMID vx_pyramid
VX_TYPE_THRESHOLD vx_threshold
VX_TYPE_MATRIX vx_matrix
VX_TYPE_CONVOLUTION vx_convolution
VX_TYPE_SCALAR vx_scalar
VX_TYPE_ARRAY vx_array
VX_TYPE_IMAGE vx_image
VX_TYPE_REMAP vx_remap
VX_TYPE_ERROR Error object which has no type.
VX_TYPE_META_FORMAT vx_meta_format
VX_TYPE_OBJECT_ARRAY vx_object_array

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