feat(gif): support gif file

See .gif file extension support and more exception handling
Fixes #105

pkg/converter/webp/webp_converter.go

@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"image"
+	_ "image/gif"
 	_ "image/jpeg"
 	"image/png"
 	"runtime"
@@ -167,10 +168,15 @@ func (converter *Converter) ConvertChapter(ctx context.Context, chapter *manga.C
 
 			splitNeeded, img, format, err := converter.checkPageNeedsSplit(page, split)
 			if err != nil {
-				select {
-				case errChan <- err:
-				case <-ctx.Done():
-					return
+				var pageIgnoredError *converterrors.PageIgnoredError
+				if errors.As(err, &pageIgnoredError) {
+					log.Info().Err(err).Msg("Page ignored due to image decode error")
+				} else {
+					select {
+					case errChan <- err:
+					case <-ctx.Done():
+						return
+					}
 				}
 				if img != nil {
 					wgConvertedPages.Add(1)
@@ -357,7 +363,7 @@ func (converter *Converter) checkPageNeedsSplit(page *manga.Page, splitRequested
 	img, format, err := image.Decode(reader)
 	if err != nil {
 		log.Debug().Uint16("page_index", page.Index).Err(err).Msg("Failed to decode page image")
-		return false, nil, format, err
+		return false, nil, format, converterrors.NewPageIgnored(fmt.Sprintf("page %d: failed to decode image (%s)", page.Index, err.Error()))
 	}
 
 	bounds := img.Bounds()