[comment {-*- tcl -*- doctools}]
[vset FORMATNAME png]
[vset FORMATFULLNAME {Portable Network Graphics format}]

[include format-header.inc]

This handler provides new additional configuration options. See
section [sectref {PNG OPTIONS}] for more detailed explanations.


[include format-middle.inc]


In addition the value for the option is treated as list and may
contain any of the special options listed in section

[sectref {PNG OPTIONS}].

[list_end]



[section {PNG OPTIONS}]

The handler provides no true options at all, but accepts pairs of keys
and values when writing a PNG file. Each pair will be written as a
named text chunk where the key provides the name of the chunk and the
value its contents.

For example

[example {
    png Author <name> Title <title> Description ...
}]


[section TRANSPARENCY]

If you want to write images to disk which contain transparency
information (e.g. PNG with alpha channel) you need at least

[package Tk] 8.3.



[list_begin definitions]
[include format-footer.inc]
