A raw pixel bitmap — produced by ExPdfium.render_page/3 (a rendered page) or
ExPdfium.image_data/3 (a decoded embedded image).
data is a raw pixel buffer. format records the byte order and channel count
so consumers can interpret it: :rgba/:bgra (4 channels), :bgrx (4, with a
padding byte), :bgr (3), or :gray (1). render_page/3 yields :rgba
(default) or :bgra; an image decoded with image_data/3 keeps its native
pdfium format. With width, height, and stride (bytes per row), the buffer
feeds directly into e.g. Vix.Vips.Image.new_from_binary/5.
Summary
Types
@type format() :: :rgba | :bgra | :bgrx | :bgr | :gray
@type t() :: %ExPdfium.Bitmap{ data: binary(), format: format(), height: non_neg_integer(), stride: non_neg_integer(), width: non_neg_integer() }