Lua: add new module `pandoc.image`

The module provides basic querying functions for image properties.

1 files changed, 61 insertions, 0 deletions

diff --git a/doc/lua-filters.md b/doc/lua-filters.md
index e1504ff13..3872e1cba 100644
--- a/doc/lua-filters.md
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@@ -4607,6 +4607,67 @@ Returns:
 
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+<!-- BEGIN: AUTOGENERATED CONTENT for module pandoc.image -->
+
+# Module pandoc.image
+
+Basic image querying functions.
+
+## Functions {#pandoc.image-functions}
+
+### size {#pandoc.image.size}
+
+`size (image[, opts])`
+
+Returns a table containing the size and resolution of an image;
+throws an error if the given string is not an image, or if the
+size of the image cannot be determined.
+
+The resulting table has four entires: *width*, *height*,
+*dpi_horz*, and *dpi_vert*.
+
+The `opts` parameter, when given, should be either a WriterOptions
+object such as `PANDOC_WRITER_OPTIONS`, or a table with a `dpi`
+entry. It affects the calculation for vector image formats such as
+SVG.
+
+Parameters:
+
+`image`
+:   image data (string)
+
+`opts`
+:   writer options ([WriterOptions]\|table)
+
+Returns:
+
+-   image size information or error message (table)
+
+*Since: 3.1.13*
+
+### format {#pandoc.image.format}
+
+`format (image)`
+
+Returns the format of an image as a lowercase string.
+
+Formats recognized by pandoc include *png*, *gif*, *tiff*, *jpeg*,
+*pdf*, *svg*, *eps*, and *emf*.
+
+Parameters:
+
+`image`
+:   binary image data (string)
+
+Returns:
+
+-   image format, or nil if the format cannot be determined
+    (string\|nil)
+
+*Since: 3.1.13*
+
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+
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 # Module pandoc.json