debian man page for dwebp

DWEBP(1)						      General Commands Manual							  DWEBP(1)

NAME
       dwebp - decompress a WebP file to an image file

SYNOPSIS
       dwebp [options] input_file.webp

DESCRIPTION
       This manual page documents the dwebp command.

       dwebp decompresses WebP files into PNG, PPM or PGM images.

OPTIONS
       The basic options are:

       -h     Print usage summary.

       -version
	      Print the version number (as major.minor.revision) and exit.

       -o string
	      Specify the name of the output file (as PNG format by default).

       -ppm   Change the output format to PPM.

       -pgm   Change  the  output  format  to PGM. The output consist of luma/chroma samples instead of RGB, using the ICM4 layout. This option is
	      mainly for verification and debugging purpose.

       -nofancy
	      Don't use the fancy upscaler for YUV420. This may lead to jaggy edges (especially the red ones), but should be faster.

       -nofilter
	      Don't use the in-loop filtering process even if it is required by the bitstream. This may produce visible blocks on the  non-compli-
	      ant output, but will make the decoding faster.

       -mt    Use multi-threading for decoding, if possible.

       -crop x_position y_position width height
	      Crop  the decoded picture to a rectangle with top-left corner at coordinates (x_position, y_position) and size width x height.  This
	      cropping area must be fully contained within the source rectangle.  The top-left corner will  be	snapped  to  even  coordinates	if
	      needed.  This option is meant to reduce the memory needed for cropping large images.  Note: the cropping is applied before any scal-
	      ing.

       -scale width height
	      Rescale the decoded picture to dimension width x height. This option is mostly intended to reducing  the	memory	needed	to  decode
	      large images, when only a small version is needed (thumbnail, preview, etc.).  Note: scaling is applied after cropping.

       -v     Print extra information (decoding time in particular).

       -noasm Disable all assembly optimizations.

Examples:
       dwebp picture.webp -o output.png
       dwebp picture.webp -ppm -o output.ppm

SEE ALSO
       cwebp(1).
       Please refer to http://code.google.com/speed/webp/ for additional information.

AUTHOR
       dwebp was written by the WebP team.
       The latest source tree is available at http://www.webmproject.org/code

       This manual page was written by Pascal Massimino <pascal.massimino@gmail.com>, for the Debian project (and may be used by others).

								September 19, 2011							  DWEBP(1)