Image Histogram

Computes image histogram from the input image. More...

Functions
VPIStatus	vpiCreateHistogramEven (uint64_t backends, VPIImageFormat fmt, float start, float end, int32_t numBins, VPIPayload *payload)
	Creates payload for Image Histogram Even algorithm. More...
VPIStatus	vpiSubmitHistogram (VPIStream stream, uint64_t backend, VPIPayload payload, VPIImage input, VPIArray output, uint64_t flags)
	Computes the image histogram. More...

Detailed Description

Computes image histogram from the input image.

Refer to Image Histogram for more details and usage examples.

Function Documentation

vpiCreateHistogramEven()

VPIStatus vpiCreateHistogramEven	(	uint64_t	backends,
		VPIImageFormat	fmt,
		float	start,
		float	end,
		int32_t	numBins,
		VPIPayload *	payload
	)

#include <vpi/algo/Histogram.h>

Creates payload for Image Histogram Even algorithm.

It calculates the image histogram assuming uniform (even) bins.

Parameters

[in]	backends	VPI backends that are eligible to execute the algorithm. Valid values: VPI_BACKEND_CPU VPI_BACKEND_CUDA Backend must be enabled in current context.
[in]	fmt	Format of input image. The accepted image formats are: VPI_IMAGE_FORMAT_U8 VPI_IMAGE_FORMAT_U16
[in]	start	Specifies the low end of the histogram range (inclusive). Must be <= end.
[in]	end	Specifies the high end of the histogram range (exclusive). Must be >= start.
[in]	numBins	Specifies the number of bins in the output array. Maximum number of bins depends on input image format: VPI_IMAGE_FORMAT_U8 : 256 VPI_IMAGE_FORMAT_U16 : 65536
[out]	payload	Pointer to the payload variable that receives the created handle.

Return values

VPI_ERROR_INVALID_ARGUMENT	payload is NULL.
VPI_ERROR_INVALID_ARGUMENT	Maximum allowed numBins for given fmt outside valid range.
VPI_ERROR_INVALID_ARGUMENT	Invalid start and end values.
VPI_ERROR_INVALID_ARGUMENT	backends refers to an invalid backend.
VPI_ERROR_NOT_IMPLEMENTED	Histogram Even algorithm is not supported by given backends.
VPI_ERROR_INVALID_CONTEXT	Current context was destroyed.
VPI_IMAGE_FORMAT_INVALID	fmt is not supported.
VPI_ERROR_OUT_OF_MEMORY	Cannot allocate required resources.
VPI_ERROR_INVALID_OPERATION	Backend isn't enabled in current context.
VPI_SUCCESS	Operation executed successfully.

vpiSubmitHistogram()

VPIStatus vpiSubmitHistogram	(	VPIStream	stream,
		uint64_t	backend,
		VPIPayload	payload,
		VPIImage	input,
		VPIArray	output,
		uint64_t	flags
	)

#include <vpi/algo/Histogram.h>

Computes the image histogram.

Parameters

[in]	stream	The stream where the operation will be queued in. Must not be NULL. Stream must have enabled the backends that will execute the algorithm.
[in]	backend	Backend that will execute the algorithm. Must be the backend specified during payload creation or 0 as a shorthand to use this backend.
[in]	payload	Payload created by vpiCreateHistogramEven.
[in]	input	Input image. Must not be NULL. Must have same format as the one specified during payload creation. Image must have enabled the backends that will execute the algorithm.
[out]	output	Where the resulting image histogram will be written to. Must not be NULL. Array's capacity must be greater or equal than the number of bins configured in the payload. Array must have enabled the backends that will execute the algorithm.
[in]	flags	Control flags. Valid values are a combination of one or more of the following flags: 0: Output will be zeroed out first. VPI_ACCUMULATE_OUTPUT : accumulate on existing output values.

Return values

VPI_ERROR_INVALID_ARGUMENT	stream is NULL.
VPI_ERROR_INVALID_ARGUMENT	input or output are NULL.
VPI_ERROR_INVALID_ARGUMENT	payload not created by vpiCreateHistogramEven.
VPI_ERROR_INVALID_ARGUMENT	output array's capacity outside valid range.
VPI_ERROR_INVALID_ARRAY_TYPE	output array type not supported.
VPI_ERROR_INVALID_IMAGE_FORMAT	input image format does not match with one associated with payload.
VPI_ERROR_INVALID_PAYLOAD_TYPE	payload is invalid.
VPI_ERROR_INVALID_OPERATION	The needed backends aren't enabled in stream, input or output.
VPI_SUCCESS	Operation executed successfully.