Class cv::freetype::FreeType2#

#include <opencv2/freetype.hpp>

Collaboration diagram for cv::freetype::FreeType2:

Public Member Functions#

Public Member Functions inherited from cv::Algorithm

Return	Name	Description
	`Algorithm()`
	`~Algorithm()`
`void`	`clear()`	Clears the algorithm state.
`bool`	`empty()`	Returns true if the Algorithm is empty (e.g. in the very beginning or after unsuccessful read.
`String`	`getDefaultName()`
`void`	`read(const FileNode & fn)`	Reads algorithm parameters from a file storage.
`void`	`save(const String & filename)`
`void`	`write(` `const Ptr< FileStorage > & fs,` `const String & name = String() )`
`void`	`write(FileStorage & fs)`	Stores algorithm parameters in a file storage.
`void`	`write(` `FileStorage & fs,` `const String & name )`

Static Public Member Functions#

Static Public Member Functions inherited from cv::Algorithm

Return	Name	Description
`static Ptr< _Tp >`	`load(` `const String & filename,` `const String & objname = String() )`	Loads algorithm from the file.
`static Ptr< _Tp >`	`loadFromString(` `const String & strModel,` `const String & objname = String() )`	Loads algorithm from a String.
`static Ptr< _Tp >`	`read(const FileNode & fn)`	Reads algorithm from the file node.

Additional Inherited Members#

Member Function Documentation#

getTextSize()#

Size cv::freetype::FreeType2::getTextSize(
const String & text,
int fontHeight,
int thickness,
int * baseLine )

Python:

cv.freetype.FreeType2.getTextSize(text, fontHeight, thickness) -> retval, baseLine

Calculates the width and height of a text string.

The function getTextSize calculates and returns the approximate size of a box that contains the specified text. That is, the following code renders some text, the tight box surrounding it, and the baseline: :

String text = "Funny text inside the box";
int fontHeight = 60;
int thickness = -1;
int linestyle = LINE_8;

Mat img(600, 800, CV_8UC3, Scalar::all(0));

int baseline=0;

cv::Ptr<cv::freetype::FreeType2> ft2;
ft2 = cv::freetype::createFreeType2();
ft2->loadFontData( "./mplus-1p-regular.ttf", 0 );

Size textSize = ft2->getTextSize(text,
                                 fontHeight,
                                 thickness,
                                 &baseline);

if(thickness > 0){
    baseline += thickness;
}

// center the text
Point textOrg((img.cols - textSize.width) / 2,
              (img.rows + textSize.height) / 2);

// draw the box
rectangle(img, textOrg + Point(0, baseline),
          textOrg + Point(textSize.width, -textSize.height),
          Scalar(0,255,0),1,8);

// ... and the baseline first
line(img, textOrg + Point(0, thickness),
     textOrg + Point(textSize.width, thickness),
     Scalar(0, 0, 255),1,8);

// then put the text itself
ft2->putText(img, text, textOrg, fontHeight,
             Scalar::all(255), thickness, linestyle, true );

loadFontData()#

void cv::freetype::FreeType2::loadFontData(
char * pBuf,
size_t bufSize,
int idx )

Python:

cv.freetype.FreeType2.loadFontData(fontFileName, idx)

cv.freetype.FreeType2.loadFontData(pBuf, bufSize, idx)

Load font data.

The function loadFontData loads font data from memory. The data is not copied, the user needs to make sure the data lives at least as long as FreeType2. After the FreeType2 object is destroyed, the buffer can be safely deallocated.

Parameters

pBuf — pointer to buffer containing font data
bufSize — size of buffer
idx — face_index to select a font faces in a single file.

loadFontData()#

void cv::freetype::FreeType2::loadFontData(
String fontFileName,
int idx )

Python:

cv.freetype.FreeType2.loadFontData(fontFileName, idx)

cv.freetype.FreeType2.loadFontData(pBuf, bufSize, idx)

Load font data.

The function loadFontData loads font data from file.

Parameters

fontFileName — FontFile Name
idx — face_index to select a font faces in a single file.

putText()#

void cv::freetype::FreeType2::putText(
InputOutputArray img,
const String & text,
Point org,
int fontHeight,
Scalar color,
int thickness,
int line_type,
bool bottomLeftOrigin )

Python:

cv.freetype.FreeType2.putText(img, text, org, fontHeight, color, thickness, line_type, bottomLeftOrigin) -> img

Draws a text string.

The function putText renders the specified text string in the image. Symbols that cannot be rendered using the specified font are replaced by “Tofu” or non-drawn.

Parameters

img — Image. (Only 8UC1/8UC3/8UC4 2D mat is supported.)
text — Text string to be drawn.
org — Bottom-left/Top-left corner of the text string in the image.
fontHeight — Drawing font size by pixel unit.
color — Text color.
thickness — Thickness of the lines used to draw a text when negative, the glyph is filled. Otherwise, the glyph is drawn with this thickness.
line_type — Line type. See the line for details.
bottomLeftOrigin — When true, the image data origin is at the bottom-left corner. Otherwise, it is at the top-left corner.

setSplitNumber()#

void cv::freetype::FreeType2::setSplitNumber(int num)

Python:

cv.freetype.FreeType2.setSplitNumber(num)

Set Split Number from Bezier-curve to line.

The function setSplitNumber set the number of split points from bezier-curve to line. If you want to draw large glyph, large is better. If you want to draw small glyph, small is better.

Parameters

num — number of split points from bezier-curve to line

Source file#

The documentation for this class was generated from the following file:

opencv2/freetype.hpp