github.com/linchen2chris/hugo@v0.0.0-20230307053224-cec209389705/resources/images/image_resource.go (about)

     1  // Copyright 2022 The Hugo Authors. All rights reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  // http://www.apache.org/licenses/LICENSE-2.0
     7  //
     8  // Unless required by applicable law or agreed to in writing, software
     9  // distributed under the License is distributed on an "AS IS" BASIS,
    10  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package images
    15  
    16  import (
    17  	"image"
    18  
    19  	"github.com/gohugoio/hugo/resources/images/exif"
    20  	"github.com/gohugoio/hugo/resources/resource"
    21  )
    22  
    23  // ImageResource represents an image resource.
    24  type ImageResource interface {
    25  	resource.Resource
    26  	ImageResourceOps
    27  }
    28  
    29  type ImageResourceOps interface {
    30  	// Height returns the height of the Image.
    31  	Height() int
    32  
    33  	// Width returns the width of the Image.
    34  	Width() int
    35  
    36  	// Crop an image to match the given dimensions without resizing.
    37  	// You must provide both width and height.
    38  	// Use the anchor option to change the crop box anchor point.
    39  	//    {{ $image := $image.Crop "600x400" }}
    40  	Crop(spec string) (ImageResource, error)
    41  
    42  	// Fill scales the image to the smallest possible size that will cover the specified dimensions in spec,
    43  	// crops the resized image to the specified dimensions using the given anchor point.
    44  	// The spec is space delimited, e.g. `200x300 TopLeft`.
    45  	Fill(spec string) (ImageResource, error)
    46  
    47  	// Fit scales down the image using the given spec.
    48  	Fit(spec string) (ImageResource, error)
    49  
    50  	// Resize resizes the image to the given spec. If one of width or height is 0, the image aspect
    51  	// ratio is preserved.
    52  	Resize(spec string) (ImageResource, error)
    53  
    54  	// Filter applies one or more filters to an Image.
    55  	//    {{ $image := $image.Filter (images.GaussianBlur 6) (images.Pixelate 8) }}
    56  	Filter(filters ...any) (ImageResource, error)
    57  
    58  	// Exif returns an ExifInfo object containing Image metadata.
    59  	Exif() *exif.ExifInfo
    60  
    61  	// Colors returns a slice of the most dominant colors in an image
    62  	// using a simple histogram method.
    63  	Colors() ([]string, error)
    64  
    65  	// Internal
    66  	DecodeImage() (image.Image, error)
    67  }