images

Documentation

Overview

Package images generate thumbnails and converts these between image formats.

Index

• Constants
• Variables
• func Copy(dest, src string) error
• func Duplicate(name, suffix string) (string, error)
• func Fix(db *sql.DB, w io.Writer) error
• func Generate(w io.Writer, src, id string, remove bool) error
• func Info(name string) (width int, height int, format string, err error)
• func Libraries(w io.Writer, src, pngDest string, remove bool) error
• func Move(dest, src string) error
• func ReplaceExt(ext, name string) string
• func ToPNG(src, dest string, width, height int) (string, error)
• func ToThumb(src, dest string, sizeSquared int) (string, error)
• func ToWebp(w io.Writer, src, dest string, vendorTempDir bool) (string, error)
• func WebPCalc(width, height int) (w, h int)
• func Width(name string) (int, error)

Constants

const (
	WebpMaxSize int = 16383 // WebpMaxSize is the maximum pixel dimension of an webp image.

)

Variables

var ErrFormat = errors.New("unsupported image format")

Functions

func Copy

func Copy(dest, src string) error

Copy a file from the source location to the destination.

func Duplicate

func Duplicate(name, suffix string) (string, error)

Duplicate an image file and appends the suffix to its name.

func Fix

func Fix(db *sql.DB, w io.Writer) error

Fix generates any missing assets from downloads that are images.

func Generate

func Generate(w io.Writer, src, id string, remove bool) error

Generate a collection of site images.

func Info

func Info(name string) (
	width int, height int, format string, err error,
)

Info returns the image metadata.

func Libraries

func Libraries(w io.Writer, src, pngDest string, remove bool) error

func Move

func Move(dest, src string) error

Move a file from the source location to the destination. This is used in situations where os.rename() fails due to multiple partitions.

func ReplaceExt

func ReplaceExt(ext, name string) string

ReplaceExt replaces or appends the extension to a file name.

func ToPNG

func ToPNG(src, dest string, width, height int) (string, error)

ToPNG converts any supported format to a compressed PNG image. helpful: https://www.programming-books.io/essential/ go/images-png-jpeg-bmp-tiff-webp-vp8-gif-c84a45304ec3498081c67aa1ea0d9c49.

func ToThumb

func ToThumb(src, dest string, sizeSquared int) (string, error)

ToThumb creates a thumb from an image that is pixel squared in size.

func ToWebp

func ToWebp(w io.Writer, src, dest string, vendorTempDir bool) (string, error)

ToWebp converts any supported format to a WebP image using a 3rd party library. Input format can be either GIF, PNG, JPEG, TIFF, WebP or raw Y'CbCr samples.

func WebPCalc

func WebPCalc(width, height int) (w, h int)

WebPCalc calculates the largest permitted sizes for a valid WebP crop.

func Width

func Width(name string) (int, error)

Width returns the image width in pixels.