byjp.me
A tool for archiving & converting scans of postcards, and information about them.
fix: svg decoding
There's an occasional bug with the JPEGs within SVGs, in that they don't decode properly. I need to write tests and investigate.
+51
-3
+1
-1
formats/web/postcard.svg.qtpl
+1
-1
formats/web/postcard.svg.qtpl
+1
-2
formats/web/postcard.svg.qtpl.go
+1
-2
formats/web/postcard.svg.qtpl.go
+1
internal/images/decode.go
+1
internal/images/decode.go
+48
internal/images/svg.go
+48
internal/images/svg.go
···
1
+
package images
2
+
3
+
import (
4
+
"bytes"
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+
"encoding/base64"
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+
"encoding/xml"
7
+
"fmt"
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+
"image"
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+
"io"
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"strings"
11
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)
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+
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func ReadSVG(r io.Reader) (image.Image, []byte, error) {
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imgBytes, err := extractImageHref(r)
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if err != nil {
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return nil, nil, err
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}
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return ReadJPEG(bytes.NewReader(imgBytes))
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}
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+
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const base64prefix = "data:image/jpeg;base64,"
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+
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func extractImageHref(r io.Reader) ([]byte, error) {
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decoder := xml.NewDecoder(r)
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for {
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tok, err := decoder.Token()
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if err == io.EOF {
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return nil, fmt.Errorf("no postcard image found in SVG")
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} else if err != nil {
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return nil, fmt.Errorf("unable to parse SVG: %w", err)
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}
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switch se := tok.(type) {
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case xml.StartElement:
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if se.Name.Local == "image" {
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for _, attr := range se.Attr {
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if attr.Name.Local == "href" {
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if strings.HasPrefix(attr.Value, base64prefix) {
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b64 := attr.Value[len(base64prefix):]
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return base64.StdEncoding.DecodeString(b64)
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}
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}
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}
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}
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}
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}
48
+
}