[comment {-*- tcl -*- doctools}]
[vset FORMATNAME ppm]
[vset FORMATFULLNAME {Portable Pixmap format}]

[include format-header.inc]

This handler provides additional configuration options. See
section [sectref {PPM 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 {PPM OPTIONS}].

[list_end]

[section {SUPPORTED PPM TYPES}]

This handler supports the PPM (Truecolor) and PGM (Greyscale) image formats.
There are two types of PPM/PGM files: RAW (binary) and ASCII.
The values stored in PPM/PGM files can be unsigned 8-bit or unsigned 16-bit
values.

[example_begin]

 Grayscale (PGM): 8-bit and 16-bit, 1 channel per pixel.
 Truecolor (PPM): 8-bit and 16-bit, 3 channels per pixel.

 List of currently supported features:

 Type              |     Read      |     Write     |
                   | -file | -data | -file | -data |
 ---------------------------------------------------
 PGM  8-bit ASCII  | Yes   | Yes   | No    | No    |
 PGM  8-bit BINARY | Yes   | Yes   | No    | No    |
 PGM 16-bit ASCII  | Yes   | Yes   | No    | No    |
 PGM 16-bit BINARY | Yes   | Yes   | No    | No    |
 PPM  8-bit ASCII  | Yes   | Yes   | Yes   | Yes   |
 PPM  8-bit BINARY | Yes   | Yes   | Yes   | Yes   |
 PPM 16-bit ASCII  | Yes   | Yes   | No    | No    |
 PPM 16-bit BINARY | Yes   | Yes   | No    | No    |

[example_end]

[section {PPM OPTIONS}]

The handler provides the following options:

[list_begin definitions]

[lst_item "[option -verbose] [arg bool]"]

This option is supported for reading and writing.
[nl]
If set to [const true], additional information about the loaded/stored image
is printed to stdout. Default is [const false].

[lst_item "[option -scanorder] [arg string]"]

This option is supported for reading only.
[nl]
Specify the scanline order of the input image.
Possible values: [const TopDown] or [const BottomUp]. Default is [const TopDown].

[lst_item "[option -gamma] [arg float]"]

This option is supported for reading only.
[nl]
Specify a gamma correction to be applied when mapping
16-bit input data to 8-bit image values.
Default is [const 1.0].

[lst_item "[option -min] [arg float]"]

This option is supported for reading only.
[nl]
Specify the minimum pixel value to be used for mapping
16-bit input data to 8-bit image values.
Default is the minimum value found in the image data.

[lst_item "[option -max] [arg float]"]

This option is supported for reading only.
[nl]
Specify the maximum pixel value to be used for mapping
16-bit input data to 8-bit image values.
Default is the maximum value found in the image data.

[lst_item "[option -ascii] [arg bool]"]

This option is supported for writing only.
If set to [const true], the file is written in PPM 8-bit ASCII format (P3).
Default is [const false], i.e. write in PPM 8-bit binary format (P6).

[list_end]

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