ImageConvert¶

class ImageConvert¶

Bases: pybind11_object

Convert image types.

The following example available in tutorial-image-converter.cpp shows how to convert an OpenCV cv::Mat image into a vpImage :

#include <visp3/core/vpImageConvert.h>
#include <visp3/io/vpImageIo.h>

#if defined(VISP_HAVE_OPENCV) && defined(HAVE_OPENCV_IMGCODECS) && defined(HAVE_OPENCV_IMGPROC)
#include <opencv2/imgcodecs.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#endif

int main()
{
#if defined(VISP_HAVE_OPENCV) && defined(HAVE_OPENCV_HIGHGUI) && defined(HAVE_OPENCV_IMGPROC) && defined(HAVE_OPENCV_IMGCODECS)
  try {
    cv::Mat A;
#if VISP_HAVE_OPENCV_VERSION >= 0x030200
    int flags = cv::IMREAD_GRAYSCALE | cv::IMREAD_IGNORE_ORIENTATION;
#elif VISP_HAVE_OPENCV_VERSION >= 0x030000
    int flags = cv::IMREAD_GRAYSCALE;
#else
    int flags = CV_LOAD_IMAGE_GRAYSCALE;
#endif

    A = cv::imread("monkey.bmp", flags);

    vpImage<unsigned char>  I;
    vpImageConvert::convert (A, I);

#ifdef VISP_HAVE_PNG
    vpImageIo::write (I, "monkey.png"); // Gray
#endif
  }
  catch (const vpException  &e) {
    std::cout << "Catch an exception: " << e << std::endl;
  }
#endif
}

Methods

`BGRToRGBa`	See C++ documentation of the function for more info
`BGRaToRGBa`	See C++ documentation of the function for more info
`GreyToRGB`	See C++ documentation of the function for more info
`GreyToRGBa`	See C++ documentation of the function for more info
`HSVToRGB`	Overloaded function.
`HSVToRGBa`	Overloaded function.
`MONO16ToGrey`	See C++ documentation of the function for more info
`MONO16ToRGBa`	See C++ documentation of the function for more info
`RGBToGrey`	See C++ documentation of the function for more info
`RGBToHSV`	Overloaded function.
`RGBToRGBa`	See C++ documentation of the function for more info
`RGBaToGrey`	See C++ documentation of the function for more info
`RGBaToHSV`	Overloaded function.
`RGBaToRGB`	See C++ documentation of the function for more info
`YCbCrToGrey`
`YCbCrToRGB`
`YCbCrToRGBa`
`YCrCbToRGB`
`YCrCbToRGBa`
`YUV411ToGrey`
`YUV411ToRGB`
`YUV411ToRGBa`
`YUV420ToGrey`
`YUV420ToRGB`
`YUV420ToRGBa`
`YUV422ToGrey`
`YUV422ToRGB`
`YUV422ToRGBa`
`YUV444ToGrey`	See C++ documentation of the function for more info
`YUV444ToRGB`	See C++ documentation of the function for more info
`YUV444ToRGBa`	See C++ documentation of the function for more info
`YUVToRGB`	Converts a yuv pixel value in rgb format.
`YUYVToGrey`
`YUYVToRGB`
`YUYVToRGBa`
`YV12ToRGB`
`YV12ToRGBa`
`YVU9ToRGB`
`YVU9ToRGBa`
`__init__`
`convert`	Overloaded function.
`createDepthHistogram`	Overloaded function.
`demosaicBGGRToRGBaBilinear`	Overloaded function.
`demosaicBGGRToRGBaMalvar`	Overloaded function.
`demosaicGBRGToRGBaBilinear`	Overloaded function.
`demosaicGBRGToRGBaMalvar`	Overloaded function.
`demosaicGRBGToRGBaBilinear`	Overloaded function.
`demosaicGRBGToRGBaMalvar`	Overloaded function.
`demosaicRGGBToRGBaBilinear`	Overloaded function.
`demosaicRGGBToRGBaMalvar`	Overloaded function.

Inherited Methods

Operators

`__doc__`
`__init__`
`__module__`

Attributes

`__annotations__`

static BGRToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8], flip: bool = False) → None¶: See C++ documentation of the function for more info

static BGRaToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8], flip: bool = False) → None¶: See C++ documentation of the function for more info

static GreyToRGB(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶: See C++ documentation of the function for more info

static GreyToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶: See C++ documentation of the function for more info

static HSVToRGB(*args, **kwargs)¶

Overloaded function.

HSVToRGB(hsv: numpy.ndarray[numpy.uint8], rgb: numpy.ndarray[numpy.uint8], h_full: bool = True) -> None

Convert from HSV Planes (as a 3 x H x W array) to a an RGB/RGBA array (as an H x W x 3 or H x W x 4 array)

HSVToRGB(hsv: numpy.ndarray[numpy.float64], rgb: numpy.ndarray[numpy.uint8]) -> None

Convert from HSV Planes (as a 3 x H x W array) to a an RGB/RGBA array (as an H x W x 3 or H x W x 4 array)

static HSVToRGBa(*args, **kwargs)¶

Overloaded function.

HSVToRGBa(hsv: numpy.ndarray[numpy.uint8], rgb: numpy.ndarray[numpy.uint8], h_full: bool = True) -> None

Convert from HSV Planes (as a 3 x H x W array) to a an RGB/RGBA array (as an H x W x 3 or H x W x 4 array)

HSVToRGBa(hsv: numpy.ndarray[numpy.float64], rgb: numpy.ndarray[numpy.uint8]) -> None

Convert from HSV Planes (as a 3 x H x W array) to a an RGB/RGBA array (as an H x W x 3 or H x W x 4 array)

static MONO16ToGrey(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶: See C++ documentation of the function for more info

static MONO16ToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶: See C++ documentation of the function for more info

static RGBToGrey(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶: See C++ documentation of the function for more info

static RGBToHSV(*args, **kwargs)¶

Overloaded function.

RGBToHSV(rgb: numpy.ndarray[numpy.uint8], hsv: numpy.ndarray[numpy.uint8], h_full: bool = True) -> None

Convert from HSV Planes (as a 3 x H x W array) to a an RGB/RGBA array (as an H x W x 3 or H x W x 4 array)

RGBToHSV(rgb: numpy.ndarray[numpy.uint8], hsv: numpy.ndarray[numpy.float64]) -> None

Convert from HSV Planes (as a 3 x H x W array) to a an RGB/RGBA array (as an H x W x 3 or H x W x 4 array)

static RGBToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶: See C++ documentation of the function for more info

static RGBaToGrey(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶: See C++ documentation of the function for more info

static RGBaToHSV(*args, **kwargs)¶

Overloaded function.

RGBaToHSV(rgb: numpy.ndarray[numpy.uint8], hsv: numpy.ndarray[numpy.uint8], h_full: bool = True) -> None

Convert from HSV Planes (as a 3 x H x W array) to a an RGB/RGBA array (as an H x W x 3 or H x W x 4 array)

RGBaToHSV(rgb: numpy.ndarray[numpy.uint8], hsv: numpy.ndarray[numpy.float64]) -> None

Convert from HSV Planes (as a 3 x H x W array) to a an RGB/RGBA array (as an H x W x 3 or H x W x 4 array)

static RGBaToRGB(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶: See C++ documentation of the function for more info

static YCbCrToGrey(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YCbCrToRGB(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YCbCrToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YCrCbToRGB(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YCrCbToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUV411ToGrey(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUV411ToRGB(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUV411ToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUV420ToGrey(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUV420ToRGB(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUV420ToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUV422ToGrey(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUV422ToRGB(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUV422ToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUV444ToGrey(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶: See C++ documentation of the function for more info

static YUV444ToRGB(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶: See C++ documentation of the function for more info

static YUV444ToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶: See C++ documentation of the function for more info

static YUVToRGB(y: int, u: int, v: int, r: int, g: int, b: int) → None¶

Converts a yuv pixel value in rgb format.

Parameters:

y: int¶

Y component of a pixel.

u: int¶

U component of a pixel.

v: int¶

V component of a pixel.

r: int¶

Red component from the YUV coding format. This value is computed using:

\[r = 0.9999695*y - 0.0009508*(u-128) + 1.1359061*(v-128)\]

g: int¶

Green component from the YUV coding format. This value is computed using:

\[g = 0.9999695*y - 0.3959609*(u-128) - 0.5782955*(v-128)\]

b: int¶

Blue component from the YUV coding format. This value is computed using:

\[b = 0.9999695*y + 2.04112*(u-128) - 0.0016314*(v-128)\]

static YUYVToGrey(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUYVToRGB(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YUYVToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YV12ToRGB(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YV12ToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YVU9ToRGB(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

static YVU9ToRGBa(src: numpy.ndarray[numpy.uint8], dest: numpy.ndarray[numpy.uint8]) → None¶

__init__(*args, **kwargs)¶

static convert(*args, **kwargs)¶

Overloaded function.

convert(src: visp._visp.core.ImageGray, dest: visp._visp.core.ImageRGBa) -> None

Convert a vpImage <unsigned char> to a vpImage < vpRGBa >. Tha alpha component is set to vpRGBa::alpha_default .

Note

See GreyToRGBa()

Parameters:

src: Source image
dest: Destination image.

convert(src: visp._visp.core.ImageRGBa, dest: visp._visp.core.ImageGray, nThreads: int = 0) -> None

Convert a vpImage <unsigned char> to a vpImage < vpRGBa >

Note

See RGBaToGrey()

Parameters:

src: Source image
dest: Destination image.
nThreads: Number of threads to use if OpenMP is available. If 0 is passed, OpenMP will choose the number of threads.

convert(src: visp._visp.core.ImageFloat, dest: visp._visp.core.ImageGray) -> None

Convert a vpImage <float> to a vpImage <unsigned char> by renormalizing between 0 and 255.

Parameters:

src: Source image
dest: Destination image.

convert(src: visp._visp.core.ImageRGBf, dest: visp._visp.core.ImageRGBa) -> None

Convert a vpImage < vpRGBf > to a vpImage <unsigned char> by renormalizing between 0 and 255.

Parameters:

src: Source image
dest: Destination image.

convert(src: visp._visp.core.ImageGray, dest: visp._visp.core.ImageFloat) -> None

Convert a vpImage <unsigned char> to a vpImage <float> by basic casting.

Parameters:

src: Source image
dest: Destination image.

convert(src: visp._visp.core.ImageDouble, dest: visp._visp.core.ImageGray) -> None

Convert a vpImage <double> to a vpImage <unsigned char> by renormalizing between 0 and 255.

Parameters:

src: Source image
dest: Destination image.

convert(src: visp._visp.core.ImageGray, dest: visp._visp.core.ImageDouble) -> None

Convert a vpImage <unsigned char> to a vpImage <double> by basic casting.

Parameters:

src: Source image
dest: Destination image.

convert(src: visp._visp.core.ImageUInt16, dest: visp._visp.core.ImageGray, bitshift: int) -> None

Convert a vpImage <uint16_t> to a vpImage <unsigned char>.

Parameters:

src: Source image
dest: Destination image.
bitshift: Right bit shift applied to each source element.

convert(src: visp._visp.core.ImageGray, dest: visp._visp.core.ImageUInt16, bitshift: int) -> None

Convert a vpImage <unsigned char> to a vpImage <uint16_t>.

Parameters:

src: Source image
dest: Destination image.
bitshift: Left bit shift applied to each source element.

convert(src: cv::Mat, dest: visp._visp.core.ImageRGBa, flip: bool = false) -> None

Convert a cv::Mat to a vpImage < vpRGBa >.

A cv::Mat is an OpenCV image class.

If the input image is of type CV_8UC1 or CV_8UC3, the alpha channel is set to vpRGBa::alpha_default , or 0 in certain case (see the warning below).

Warning

This function is only available if OpenCV (version 2.1.0 or greater) was detected during the configuration step.

Warning

If ViSP is built with SSSE3 flag and the CPU supports this intrinsics set, alpha channel will be set to 0, otherwise it will be set to vpRGBa::alpha_default (255).

#include <visp3/core/vpImage.h>
#include <visp3/core/vpImageConvert.h>
#include <visp3/core/vpRGBa.h>
#include <visp3/io/vpImageIo.h>

int main()
{
#if defined(VISP_HAVE_OPENCV)
  vpImage<vpRGBa> Ic; // A color image
  cv::Mat Ip;

  // Read an image on a disk with openCV library
  Ip = cv::imread("image.pgm", cv::IMREAD_COLOR); // Second parameter for a BGR encoding.
  // Convert the grayscale cv::Mat into vpImage<vpRGBa>
  vpImageConvert::convert(Ip, Ic);

  // ...
#endif
}

Parameters:

src: Source image in OpenCV format.
dest: Destination image in ViSP format.
flip: Set to true to vertically flip the converted image.

convert(src: cv::Mat, dest: visp._visp.core.ImageGray, flip: bool = false, nThreads: int = 0) -> None

Convert a cv::Mat to a vpImage <unsigned char>.

A cv::Mat is an OpenCV image class.

Warning

This function is only available if OpenCV was detected during the configuration step.

#include <visp3/core/vpImage.h>
#include <visp3/core/vpImageConvert.h>
#include <visp3/io/vpImageIo.h>

int main()
{
#if defined(VISP_HAVE_OPENCV)
  vpImage<unsigned char> Ig; // A grayscale image
  cv::Mat Ip;

  // Read an image on a disk with openCV library
  Ip = cv::imread("image.pgm", cv::IMREAD_GRAYSCALE); // Second parameter for a gray level.
  // Convert the grayscale cv::Mat into vpImage<unsigned char>
  vpImageConvert::convert(Ip, Ig);

  // ...
#endif
}

Parameters:

src: Source image in OpenCV format.
dest: Destination image in ViSP format.
flip: Set to true to vertically flip the converted image.
nThreads: number of threads to use if OpenMP is available. If 0 is passed, OpenMP will choose the number of threads.

convert(src: cv::Mat, dest: visp._visp.core.ImageFloat, flip: bool = false) -> None

Converts cv::Mat CV_32FC1 format to ViSP vpImage<float> .

Parameters:

src: OpenCV image in CV_32FC1 format.
dest: ViSP image in float format.
flip: When true during conversion flip image vertically.

convert(src: cv::Mat, dest: visp._visp.core.ImageDouble, flip: bool = false) -> None

Converts cv::Mat CV_32FC1 format to ViSP vpImage<double> .

Parameters:

src: OpenCV image in CV_32FC1 format.
dest: ViSP image in double format.
flip: When true during conversion flip image vertically.

convert(src: cv::Mat, dest: visp._visp.core.ImageRGBf, flip: bool = false) -> None

Converts cv::Mat CV_32FC3 format to ViSP vpImage<vpRGBf>.

Parameters:

src: OpenCV image in CV_32FC3 format.
dest: ViSP image in vpRGBf format.
flip: When true during conversion flip image vertically.

convert(src: cv::Mat, dest: visp._visp.core.ImageUInt16, flip: bool = false) -> None

Converts cv::Mat CV_16UC1 format to ViSP vpImage<uint16_t>.

Parameters:

src: OpenCV image in CV_16UC1 format.
dest: ViSP image in uint16_t format.
flip: When true during conversion flip image vertically.

convert(src: visp._visp.core.ImageRGBa, dest: cv::Mat) -> None

Convert a vpImage < vpRGBa > to a cv::Mat color image.

A cv::Mat is an OpenCV image class. See http://opencv.willowgarage.com for the general OpenCV documentation, or http://opencv.willowgarage.com/documentation/cpp/core_basic_structures.html for the specific Mat structure documentation.

Warning

This function is only available if OpenCV version 2.1.0 or greater was detected during the configuration step.

#include <visp3/core/vpImageConvert.h>
#include <visp3/io/vpImageIo.h>

int main()
{
#if defined(VISP_HAVE_OPENCV)
  vpImage<vpRGBa> I; // A color image
  cv::Mat Icv;

  // Read an image on a disk
  vpImageIo::read(I, "image.ppm");
  // Convert the image into color cv::Mat.
  vpImageConvert::convert(I, Icv);
  // Treatments on cv::Mat Icv
  //...
  // Save the cv::Mat on the disk
  cv::imwrite("image-cv.ppm", Icv);
#endif
}

Parameters:

src: Source image ( vpRGBa format).
dest: Destination image (BGR format).

convert(src: visp._visp.core.ImageGray, dest: cv::Mat, copyData: bool = true) -> None

Convert a vpImage <unsigned char> to a cv::Mat grey level image.

Warning

This function is only available if OpenCV version 2.1.0 or greater was detected during the configuration step.

#include <visp3/core/vpImageConvert.h>
#include <visp3/io/vpImageIo.h>

int main()
{
#if defined(VISP_HAVE_OPENCV) && defined(HAVE_OPENCV_IMGPROC) && defined(HAVE_OPENCV_IMGCODECS)
  vpImage<unsigned char> Ig; // A grayscale image
  cv::Mat Ip;

  // Read an image on a disk
  vpImageIo::read(Ig, "image.pgm");
  // Convert the vpImage<unsigned char> in to grayscale cv::Mat
  vpImageConvert::convert(Ig, Ip);
  // Treatments on cv::Mat Ip
  //...
  // Save the cv::Mat on the disk
  cv::imwrite("image-cv.pgm", Ip);
#endif
}

Parameters:

src: Source image.
dest: Destination image.
copyData: If true, the image is copied and modification in one object will not modified the other.

convert(src: visp._visp.core.ImageFloat, dest: cv::Mat, copyData: bool = true) -> None
convert(src: visp._visp.core.ImageDouble, dest: cv::Mat, copyData: bool = true) -> None
convert(src: visp._visp.core.ImageRGBf, dest: cv::Mat) -> None

static createDepthHistogram(*args, **kwargs)¶

Overloaded function.

createDepthHistogram(src_depth: visp._visp.core.ImageUInt16, dest_rgba: visp._visp.core.ImageRGBa) -> None

Convert the input 16-bits depth image to a color depth image. The input depth value is assigned a color value proportional to its frequency. Tha alpha component of the resulting image is set to vpRGBa::alpha_default .

Parameters:

src_depth: Input 16-bits depth image.
dest_rgba: Output color depth image.

createDepthHistogram(src_depth: visp._visp.core.ImageUInt16, dest_depth: visp._visp.core.ImageGray) -> None

Convert the input 16-bits depth image to a 8-bits depth image. The input depth value is assigned a value proportional to its frequency.

Parameters:

src_depth: Input 16-bits depth image.
dest_depth: Output grayscale depth image.

createDepthHistogram(src_depth: visp._visp.core.ImageFloat, dest_depth: visp._visp.core.ImageRGBa) -> None

Convert the input float depth image to a color depth image. The input depth value is assigned a color value proportional to its frequency. The alpha component of the resulting image is set to vpRGBa::alpha_default .

Parameters:

src_depth: Input float depth image.

createDepthHistogram(src_depth: visp._visp.core.ImageFloat, dest_depth: visp._visp.core.ImageGray) -> None

Convert the input float depth image to a 8-bits depth image. The input depth value is assigned a value proportional to its frequency.

Parameters:

src_depth: Input float depth image.
dest_depth: Output grayscale depth image.

static demosaicBGGRToRGBaBilinear(*args, **kwargs)¶

Overloaded function.

demosaicBGGRToRGBaBilinear(bayer_data: numpy.ndarray[numpy.uint8], rgba: numpy.ndarray[numpy.uint8], num_threads: int = 0) -> None