Convert Image Format

Converts the image contents to the desired format, with optional scaling and offset. More...

Enumerations
enum	VPIConversionPolicy
	Policy used when converting between image types. More...

Functions
VPIStatus	vpiSubmitConvertImageFormat (VPIStream stream, VPIBackend backend, VPIImage input, VPIImage output, VPIConversionPolicy convPolicy, float scale, float offset)
	Converts the image contents to the desired format, with optional scaling and offset. More...

Detailed Description

Converts the image contents to the desired format, with optional scaling and offset.

Enumeration Type Documentation

VPIConversionPolicy

enum VPIConversionPolicy

#include <vpi/Types.h>

Policy used when converting between image types.

Enumerator
VPI_CONVERSION_INVALID	Invalid conversion.
VPI_CONVERSION_CAST	Casts input to the output type. Overflows and underflows are handled as per C specification, including situations of undefined behavior.
VPI_CONVERSION_CLAMP	Clamps input to output's type range. Overflows and underflows are mapped to the output type's maximum and minimum representable value, respectively. When output type is floating point, clamp behaves like cast.

Definition at line 328 of file Types.h.

Function Documentation

vpiSubmitConvertImageFormat()

VPIStatus vpiSubmitConvertImageFormat	(	VPIStream	stream,
		VPIBackend	backend,
		VPIImage	input,
		VPIImage	output,
		VPIConversionPolicy	convPolicy,
		float	scale,
		float	offset
	)

#include <vpi/algo/ConvertImageFormat.h>

Converts the image contents to the desired format, with optional scaling and offset.

The input and output types are inferred from the corresponding images passed as parameters. When scaling and offset are fractional, input is converted to 32-bit floating point prior conversion takes place. The formula that relates input and output pixels is:

\[ out(x,y) = clamp_{[\mathsf{min_{out}},\mathsf{max_{out}}]}(in(x,y)*\alpha + \beta) \]

where:

• \(\mathsf{min_{out}}\) and \(\mathsf{max_{out}}\) are the minimum and maximum representable value by output image format. Exception is for floating point types, where limits are \([-\infty,\infty]\), i.e., no clamping is done.
• \(\alpha\) is the scaling.
• \(\beta\) is the offset.

float to integer conversion does returns the nearest integer number, rounding halfway cases away from zero.

Parameters

[in]	stream	A stream handle where the operation will be queued into.
[in]	backend	The backend that will execute the algorithm.
[in]	input	Input image to be converted.
[out]	output	Output image where result will be written to, with the desired type.
[in]	convPolicy	Conversion policy to be used.
[in]	scale	Scaling factor. Pass 1 for no scaling.
[in]	offset	Offset factor. Pass 0 for no offset.

Returns

an error code on failure else VPI_SUCCESS