support comic without cover

README.md

@@ -96,6 +96,8 @@ Usage of go-comic-converter:
     	Manga mode (right to left)
   -noblankpage
     	Remove blank pages
+  -nocover
+    	Indicate if your comic doesn't have a cover. The first page will be used as a cover and include after the title.
   -nocrop
     	Disable cropping
   -output string

internal/epub/core.go

@@ -25,6 +25,7 @@ type ImageOptions struct {
 	AutoSplitDoublePage bool
 	NoBlankPage         bool
 	Manga               bool
+	HasCover            bool
 	Workers             int
 }
 
@@ -113,7 +114,9 @@ func (e *ePub) getParts() ([]*epubPart, error) {
 
 	parts := make([]*epubPart, 0)
 	cover := images[0]
-	images = images[1:]
+	if e.HasCover {
+		images = images[1:]
+	}
 	if e.LimitMb == 0 {
 		parts = append(parts, &epubPart{
 			Cover:  cover,
@@ -185,7 +188,7 @@ func (e *ePub) Write() error {
 
 		content := []zipContent{
 			{"META-INF/container.xml", containerTmpl},
-			{"OEBPS/content.opf", e.render(contentTmpl, map[string]any{"Info": e, "Images": part.Images})},
+			{"OEBPS/content.opf", e.render(contentTmpl, map[string]any{"Info": e, "Cover": part.Cover, "Images": part.Images})},
 			{"OEBPS/toc.ncx", e.render(tocTmpl, map[string]any{"Info": e})},
 			{"OEBPS/nav.xhtml", e.render(navTmpl, map[string]any{"Info": e})},
 			{"OEBPS/Text/style.css", styleTmpl},
@@ -204,7 +207,12 @@ func (e *ePub) Write() error {
 				return err
 			}
 		}
-		wz.WriteImage(part.Cover.Data)
+
+		// Cover exist or part > 1
+		// If no cover, part 2 and more will include the image as a cover
+		if e.HasCover || i > 0 {
+			wz.WriteImage(part.Cover.Data)
+		}
 
 		for _, img := range part.Images {
 			if err := wz.WriteFile(

internal/epub/image_data.go

@@ -22,10 +22,6 @@ func (img *ImageData) CompressedSize() uint64 {
 
 func newImageData(id int, part int, img image.Image, quality int) *ImageData {
 	name := fmt.Sprintf("OEBPS/Images/%d_p%d.jpg", id, part)
-	if id == 0 {
-		name = "OEBPS/Images/cover.jpg"
-	}
-
 	data := bytes.NewBuffer([]byte{})
 	if err := jpeg.Encode(data, img, &jpeg.Options{Quality: quality}); err != nil {
 		panic(err)

internal/epub/image_processing.go

@@ -22,11 +22,12 @@ import (
 )
 
 type Image struct {
-	Id     int
+	Id      int
-	Part   int
+	Part    int
-	Data   *ImageData
+	Data    *ImageData
-	Width  int
+	Width   int
-	Height int
+	Height  int
+	IsCover bool
 }
 
 type imageTask struct {
@@ -152,12 +153,13 @@ func LoadImages(path string, options *ImageOptions) ([]*Image, error) {
 					newImageData(img.Id, 0, dst, options.Quality),
 					dst.Bounds().Dx(),
 					dst.Bounds().Dy(),
+					img.Id == 0,
 				}
 
 				// Auto split double page
 				// Except for cover
 				// Only if the src image have width > height and is bigger than the view
-				if img.Id > 0 &&
+				if (!options.HasCover || img.Id > 0) &&
 					options.AutoSplitDoublePage &&
 					src.Bounds().Dx() > src.Bounds().Dy() &&
 					src.Bounds().Dx() > options.ViewHeight &&
@@ -173,6 +175,7 @@ func LoadImages(path string, options *ImageOptions) ([]*Image, error) {
 							newImageData(img.Id, part, dst, options.Quality),
 							dst.Bounds().Dx(),
 							dst.Bounds().Dy(),
+							false,
 						}
 					}
 				}

internal/epub/templates/content.opf.tmpl

@@ -23,12 +23,14 @@
 <manifest>
 <item id="ncx" href="toc.ncx" media-type="application/x-dtbncx+xml"/>
 <item id="nav" href="nav.xhtml" properties="nav" media-type="application/xhtml+xml"/>
-<item id="cover" href="Images/cover.jpg" media-type="image/jpeg" properties="cover-image"/>
+<item id="cover" href="Images/{{ .Cover.Id }}_p{{ .Cover.Part }}.jpg" media-type="image/jpeg" properties="cover-image"/>
 <item id="css" href="Text/style.css" media-type="text/css"/>
 <item id="page_part" href="Text/part.xhtml" media-type="application/xhtml+xml"/>
 {{ range .Images }}
 <item id="page_{{ .Id }}_p{{ .Part}}" href="Text/{{ .Id }}_p{{ .Part}}.xhtml" media-type="application/xhtml+xml"/>
+{{ if eq .IsCover false }}
 <item id="img_{{ .Id }}_p{{ .Part}}" href="Images/{{ .Id }}_p{{ .Part}}.jpg" media-type="image/jpeg"/>
+{{ end }}
 {{ if eq $info.NoBlankPage false }}
 {{ if eq .Part 1 }}
 <item id="page_{{ .Id }}_sp" href="Text/{{ .Id }}_sp.xhtml" media-type="application/xhtml+xml"/>

main.go

@@ -71,6 +71,7 @@ type Option struct {
 	AutoSplitDoublePage bool
 	NoBlankPage         bool
 	Manga               bool
+	NoCover             bool
 	Workers             int
 	LimitMb             int
 }
@@ -106,6 +107,7 @@ Options:
     AutoSplitDoublePage: %v
     NoBlankPage        : %v
     Manga              : %v
+    HasCover           : %v
     LimitMb            : %s
     Workers            : %d
 `,
@@ -122,6 +124,7 @@ Options:
 		o.AutoSplitDoublePage,
 		o.NoBlankPage,
 		o.Manga,
+		!o.NoCover,
 		limitmb,
 		o.Workers,
 	)
@@ -154,6 +157,7 @@ func main() {
 	flag.BoolVar(&opt.AutoSplitDoublePage, "autosplitdoublepage", false, "Auto Split double page when width > height")
 	flag.BoolVar(&opt.NoBlankPage, "noblankpage", false, "Remove blank pages")
 	flag.BoolVar(&opt.Manga, "manga", false, "Manga mode (right to left)")
+	flag.BoolVar(&opt.NoCover, "nocover", false, "Indicate if your comic doesn't have a cover. The first page will be used as a cover and include after the title.")
 	flag.IntVar(&opt.LimitMb, "limitmb", 0, "Limit size of the ePub: Default nolimit (0), Minimum 20")
 	flag.IntVar(&opt.Workers, "workers", runtime.NumCPU(), "Number of workers")
 	flag.Usage = func() {
@@ -261,6 +265,7 @@ func main() {
 			AutoSplitDoublePage: opt.AutoSplitDoublePage,
 			NoBlankPage:         opt.NoBlankPage,
 			Manga:               opt.Manga,
+			HasCover:            !opt.NoCover,
 			Workers:             opt.Workers,
 		},
 	}).Write(); err != nil {