htmlimg.go


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// Package htmlimg produces base64-encoded HTML <img> tags.
//
//	<img src="data:image/png;base64,iVBORw...">
package htmlimg

import (
	"bytes"
	"encoding/base64"
	"html/template"
	"image"
	"image/png"
)

// Encode PNG- and then base64-encodes img and returns it embedded in an
// HTML <img> tag.
func Encode(m image.Image) (template.HTML, error) {
	pngBuf := new(bytes.Buffer)
	if err := png.Encode(pngBuf, m); err != nil {
		return "", err
	}
	b64 := base64.StdEncoding.EncodeToString(pngBuf.Bytes())
	return template.HTML(`<img src="data:image/png;base64,` + b64 + `">`), nil
}