预定义常量

下列常量由此扩展定义，且仅在此扩展编译入 PHP 或在运行时动态载入时可用。

GD_VERSION (string)

PHP 编译所依据的 GD 版本。

GD_MAJOR_VERSION (int)

PHP 编译所依据的 GD 大版本。

GD_MINOR_VERSION (int)

PHP 编译所依据的 GD 小版本。

GD_RELEASE_VERSION (int)

PHP 编译所依据的 GD 发布版本。

GD_EXTRA_VERSION (string)

PHP 编译所依据的 GD 扩展版本（beta/rc..）。

GD_BUNDLED (int)

当使用绑定版本的 GD 时，此值为 1，反之为 0。

IMG_AVIF (int)

Used as a return value by imagetypes() （自 PHP 8.1.0 起可用）

IMG_BMP (int)

Used as a return value by imagetypes()

IMG_GIF (int)

Used as a return value by imagetypes()

IMG_JPG (int)

Used as a return value by imagetypes()

IMG_JPEG (int)

Used as a return value by imagetypes()

注意:

本常量值同 IMG_JPG

IMG_PNG (int)

Used as a return value by imagetypes()

IMG_TGA (int)

Used as a return value by imagetypes() （自 PHP 7.4.0 起可用）

IMG_WBMP (int)

Used as a return value by imagetypes()

IMG_XPM (int)

Used as a return value by imagetypes()

IMG_WEBP (int)

Used as a return value by imagetypes() （自 PHP 7.0.10 起可用）

IMG_WEBP_LOSSLESS (int)

（自 PHP 8.1.0 起可用）

IMG_COLOR_TILED (int)

Special color option which can be used instead of a color allocated with imagecolorallocate() or imagecolorallocatealpha().

IMG_COLOR_STYLED (int)

Special color option which can be used instead of a color allocated with imagecolorallocate() or imagecolorallocatealpha().

IMG_COLOR_BRUSHED (int)

Special color option which can be used instead of a color allocated with imagecolorallocate() or imagecolorallocatealpha().

IMG_COLOR_STYLEDBRUSHED (int)

Special color option which can be used instead of a color allocated with imagecolorallocate() or imagecolorallocatealpha().

IMG_COLOR_TRANSPARENT (int)

Special color option which can be used instead of a color allocated with imagecolorallocate() or imagecolorallocatealpha().

IMG_AFFINE_TRANSLATE (int)

An affine transformation type constant used by the imageaffinematrixget() function.

IMG_AFFINE_SCALE (int)

An affine transformation type constant used by the imageaffinematrixget() function.

IMG_AFFINE_ROTATE (int)

An affine transformation type constant used by the imageaffinematrixget() function.

IMG_AFFINE_SHEAR_HORIZONTAL (int)

An affine transformation type constant used by the imageaffinematrixget() function.

IMG_AFFINE_SHEAR_VERTICAL (int)

An affine transformation type constant used by the imageaffinematrixget() function.

IMG_ARC_ROUNDED (int)

A style constant used by the imagefilledarc() function.

注意:

此常量值同 IMG_ARC_PIE

IMG_ARC_PIE (int)

A style constant used by the imagefilledarc() function.

IMG_ARC_CHORD (int)

A style constant used by the imagefilledarc() function.

IMG_ARC_NOFILL (int)

A style constant used by the imagefilledarc() function.

IMG_ARC_EDGED (int)

A style constant used by the imagefilledarc() function.

IMG_GD2_RAW (int)

A type constant used by the imagegd2() function.

IMG_GD2_COMPRESSED (int)

A type constant used by the imagegd2() function.

IMG_EFFECT_REPLACE (int)

Alpha blending effect used by the imagelayereffect() function.

IMG_EFFECT_ALPHABLEND (int)

Alpha blending effect used by the imagelayereffect() function.

IMG_EFFECT_NORMAL (int)

Alpha blending effect used by the imagelayereffect() function.

IMG_EFFECT_OVERLAY (int)

Alpha blending effect used by the imagelayereffect() function.

IMG_EFFECT_MULTIPLY (int)

Alpha blending effect used by the imagelayereffect() function.

IMG_FILTER_NEGATE (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_GRAYSCALE (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_BRIGHTNESS (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_CONTRAST (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_COLORIZE (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_EDGEDETECT (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_GAUSSIAN_BLUR (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_SELECTIVE_BLUR (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_EMBOSS (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_MEAN_REMOVAL (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_SMOOTH (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_PIXELATE (int)

Special GD filter used by the imagefilter() function.

IMG_FILTER_SCATTER (int)

Special GD filter used by the imagefilter() function. （自 PHP 7.4.0 版本可用）

IMAGETYPE_GIF (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_JPEG (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_JPEG2000 (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_PNG (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_SWF (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_PSD (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_BMP (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_WBMP (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_XBM (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_TIFF_II (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_TIFF_MM (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_IFF (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_JB2 (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_JPC (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_JP2 (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_JPX (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_SWC (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_ICO (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_WEBP (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions. (从 PHP 7.1.0 开始支持)

IMAGETYPE_AVIF (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions. （自 PHP 8.1.0 起可用）

IMAGETYPE_UNKNOWN (int)

Image type constant used by the image_type_to_mime_type() and image_type_to_extension() functions.

IMAGETYPE_COUNT (int)

可用于 image_type_to_mime_type() 和 image_type_to_extension() 函数的图像类型常量编号（包括 unknown 类型）。

PNG_NO_FILTER (int)

A special PNG filter, used by the imagepng() function.

PNG_FILTER_NONE (int)

A special PNG filter, used by the imagepng() function.

PNG_FILTER_SUB (int)

A special PNG filter, used by the imagepng() function.

PNG_FILTER_UP (int)

A special PNG filter, used by the imagepng() function.

PNG_FILTER_AVG (int)

A special PNG filter, used by the imagepng() function.

PNG_FILTER_PAETH (int)

A special PNG filter, used by the imagepng() function.

PNG_ALL_FILTERS (int)

A special PNG filter, used by the imagepng() function.

IMG_FLIP_VERTICAL (int)

Used together with imageflip(), available as of PHP 5.5.0.

IMG_FLIP_HORIZONTAL (int)

Used together with imageflip(), available as of PHP 5.5.0.

IMG_FLIP_BOTH (int)

Used together with imageflip(), available as of PHP 5.5.0.

IMG_BELL (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_BESSEL (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_BILINEAR_FIXED (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_BICUBIC (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_BICUBIC (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_BLACKMAN (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_BOX (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_BSPLINE (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_CATMULLROM (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_GAUSSIAN (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_GENERALIZED_CUBIC (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_HERMITE (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_HAMMING (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_HANNING (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_MITCHELL (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_POWER (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_QUADRATIC (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_SINC (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_NEAREST_NEIGHBOUR (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_WEIGHTED4 (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_TRIANGLE (int)

Used together with imagesetinterpolation(), available as of PHP 5.5.0.

IMG_CROP_BLACK (int)

裁剪出黑色背景。

IMG_CROP_DEFAULT (int)

等同于 IMG_CROP_TRANSPARENT。在 PHP 7.4.0 之前，如果图像没有透明色，则捆绑的 libgd 将恢复为 IMG_CROP_SIDES。

IMG_CROP_SIDES (int)

使用图像的 4 个角尝试检测要裁剪的背景。

IMG_CROP_THRESHOLD (int)

使用指定 threshold 和 color 裁切图片。

IMG_CROP_TRANSPARENT (int)

裁剪出透明背景。

IMG_CROP_WHITE (int)

裁剪出白色背景。