Documentation
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Overview ¶
Package fixedlayout writes a fixed-layout EPUB 3 from the pages of a CBZ: one XHTML page per image, each sized for e-reader screens. It is plain EPUB with no Kobo markup, so both the CBZ to EPUB and the CBZ to KePub Conversions write it.
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func ConvertCBZ ¶
ConvertCBZ converts the CBZ at srcPath to a fixed-layout EPUB at destPath. It is a path-based wrapper over PrepareCBZ and Conversion.Write; downloads call those directly through pkg/filegen. metadata may be nil.
Types ¶
type Author ¶
type Author struct {
Name string
SortName string // e.g., "Doe, Jane" for sorting/file-as
Role string // writer, penciller, inker, etc.
}
Author represents an author/creator for CBZ metadata.
type Conversion ¶
type Conversion struct {
// contains filtered or unexported fields
}
Conversion is a CBZ ready to be converted to a fixed-layout EPUB.
func PrepareCBZ ¶
func PrepareCBZ(srcZip *zip.Reader, metadata *Metadata) (*Conversion, error)
PrepareCBZ finds the pages of the CBZ in srcZip and checks that each can be opened, so a CBZ the conversion cannot use fails before anything is written. Pages are read only by Write, and srcZip must stay readable until it returns.
func (*Conversion) Write ¶
Write writes the EPUB to w front to back. Each page's XHTML and image are written as soon as the page is processed, a bounded number of pages ahead, and the zip writer is flushed after each page so output arrives about once per page. The OPF, NCX, and nav list every page with its dimensions, so they come last; the container only requires mimetype first, and container.xml points to the OPF by path.
type Metadata ¶
type Metadata struct {
Title string
Subtitle *string
Description *string
Authors []Author
Series []Series
Genres []string
Tags []string
URL *string
Publisher *string
ReleaseDate *time.Time
Chapters []Chapter
CoverPage *int // 0-indexed page number for cover (nil = first page)
Language *string // BCP 47 language tag
}
Metadata is the book metadata written into the EPUB.
type ProcessedImage ¶
ProcessedImage holds the result of image processing.
func ProcessImageForEreader ¶
func ProcessImageForEreader(data []byte, origExt string) *ProcessedImage
ProcessImageForEreader resizes images to fit e-reader screen dimensions. - All JPEG/PNG images are resized to fit within Kobo Libra Color resolution (1264x1680) - PNG images are converted to JPEG for smaller file size - Other formats (GIF, WebP) are passed through unchanged.
Tones and colors are left alone: one generated file serves every reader, from e-ink to phones, so reducing grays or dropping color for a screen is left to the reading app. A page comes out gray only if it holds nothing but grays: it decoded as gray, or as a palette of grays.
pkg/filegen/cbz.go uses it too, so a change here also changes regular CBZ downloads.
Source Files