ImageMagick: MagickCore, C API for ImageMagick: Annotate an Image

AnnotateImage • FormatMagickCaption • GetMultilineTypeMetrics • GetTypeMetrics

AnnotateImage

AnnotateImage() annotates an image with text. Optionally you can include any of the following bits of information about the image by embedding the appropriate special characters:

    \n   newline
    \r   carriage return
    <    less-than character.
    >    greater-than character.
    &    ampersand character.
 a percent sign
    b   file size of image read in
    c   comment meta-data property
    d   directory component of path
    e   filename extension or suffix
    f   filename (including suffix)
    g   layer canvas page geometry   (equivalent to "WxHXY")
    h   current image height in pixels
    i   image filename (note: becomes output filename for "info:")
    k   CALCULATED: number of unique colors
    l   label meta-data property
    m   image file format (file magic)
    n   number of images in current image sequence
    o   output filename  (used for delegates)
    p   index of image in current image list
    q   quantum depth (compile-time constant)
    r   image class and colorspace
    s   scene number (from input unless re-assigned)
    t   filename without directory or extension (suffix)
    u   unique temporary filename (used for delegates)
    w   current width in pixels
    x   x resolution (density)
    y   y resolution (density)
    z   image depth (as read in unless modified, image save depth)
    A   image transparency channel enabled (true/false)
    C   image compression type
    D   image GIF dispose method
    G   original image size (wxh; before any resizes)
    H   page (canvas) height
    M   Magick filename (original file exactly as given,  including read mods)
    O   page (canvas) offset ( = XY )
    P   page (canvas) size ( = WxH )
    Q   image compression quality ( 0 = default )
    S   ?? scenes ??
    T   image time delay (in centi-seconds)
    U   image resolution units
    W   page (canvas) width
    X   page (canvas) x offset (including sign)
    Y   page (canvas) y offset (including sign)
    Z   unique filename (used for delegates)
    @   CALCULATED: trim bounding box (without actually trimming)
    #   CALCULATED: 'signature' hash of image values

The format of the AnnotateImage method is:

MagickBooleanType AnnotateImage(Image *image,DrawInfo *draw_info)

A description of each parameter follows:

image: the image.
draw_info: the draw info.

FormatMagickCaption

FormatMagickCaption() formats a caption so that it fits within the image width. It returns the number of lines in the formatted caption.

The format of the FormatMagickCaption method is:

ssize_t FormatMagickCaption(Image *image,DrawInfo *draw_info,
  const MagickBooleanType split,TypeMetric *metrics,char **caption)

A description of each parameter follows.

image

The image.

draw_info

the draw info.

split

when no convenient line breaks-- insert newline.

metrics

Return the font metrics in this structure.

caption

the caption.

GetMultilineTypeMetrics

GetMultilineTypeMetrics() returns the following information for the specified font and text:

    character width
    character height
    ascender
    descender
    text width
    text height
    maximum horizontal advance
    bounds: x1
    bounds: y1
    bounds: x2
    bounds: y2
    origin: x
    origin: y
    underline position
    underline thickness

This method is like GetTypeMetrics() but it returns the maximum text width and height for multiple lines of text.

The format of the GetMultilineTypeMetrics method is:

MagickBooleanType GetMultilineTypeMetrics(Image *image,
  const DrawInfo *draw_info,TypeMetric *metrics)

A description of each parameter follows:

image: the image.
draw_info: the draw info.
metrics: Return the font metrics in this structure.

GetTypeMetrics

GetTypeMetrics() returns the following information for the specified font and text:

    character width
    character height
    ascender
    descender
    text width
    text height
    maximum horizontal advance
    bounds: x1
    bounds: y1
    bounds: x2
    bounds: y2
    origin: x
    origin: y
    underline position
    underline thickness

The format of the GetTypeMetrics method is:

MagickBooleanType GetTypeMetrics(Image *image,const DrawInfo *draw_info,
  TypeMetric *metrics)

A description of each parameter follows:

image: the image.
draw_info: the draw info.
metrics: Return the font metrics in this structure.