dwebp(1)

1DWEBP(1)                    General Commands Manual                   DWEBP(1)
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NAME

6       dwebp - decompress a WebP file to an image file
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SYNOPSIS

9       dwebp [options] input_file.webp
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DESCRIPTION

12       This manual page documents the dwebp command.
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14       dwebp decompresses WebP files into PNG, PAM, PPM or PGM images.
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OPTIONS

17       The basic options are:
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19       -h     Print usage summary.
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21       -version
22              Print the version number (as major.minor.revision) and exit.
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24       -o string
25              Specify the name of the output file (as PNG format by default).
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27       -pam   Change the output format to PAM (retains alpha).
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29       -ppm   Change the output format to PPM (discards alpha).
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31       -pgm   Change  the  output  format  to  PGM.  The  output  consists  of
32              luma/chroma samples instead of RGB, using the ICM4 layout.  This
33              option is mainly for verification and debugging purposes.
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35       -yuv   Change  the  output  format  to  raw YUV. The output consists of
36              luma/chroma-U/chroma-V samples instead  of  RGB,  saved  sequen‐
37              tially as individual planes. This option is mainly for verifica‐
38              tion and debugging purposes.
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40       -nofancy
41              Don't use the fancy upscaler for YUV420. This may lead to  jaggy
42              edges (especially the red ones), but should be faster.
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44       -nofilter
45              Don't  use  the in-loop filtering process even if it is required
46              by the bitstream. This may produce visible blocks  on  the  non-
47              compliant output, but will make the decoding faster.
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49       -mt    Use multi-threading for decoding, if possible.
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51       -crop x_position y_position width height
52              Crop  the decoded picture to a rectangle with top-left corner at
53              coordinates (x_position, y_position) and size  width  x  height.
54              This  cropping  area  must  be fully contained within the source
55              rectangle.  The top-left corner will be snapped to even  coordi‐
56              nates  if  needed.   This  option  is meant to reduce the memory
57              needed for cropping large images.  Note: the cropping is applied
58              before any scaling.
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60       -scale width height
61              Rescale  the  decoded  picture to dimension width x height. This
62              option is mostly intended  to  reducing  the  memory  needed  to
63              decode large images, when only a small version is needed (thumb‐
64              nail, preview, etc.).  Note: scaling is applied after cropping.
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66       -v     Print extra information (decoding time in particular).
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68       -noasm Disable all assembly optimizations.
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BUGS

72       Please    report     all     bugs     to     our     issue     tracker:
73       http://code.google.com/p/webp/issues
74       Patches  welcome!  See  this  page  to get started: http://www.webmpro‐
75       ject.org/code/contribute/submitting-patches/
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EXAMPLES

79       dwebp picture.webp -o output.png
80       dwebp picture.webp -ppm -o output.ppm
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AUTHORS

84       dwebp was written by the WebP team.
85       The latest source tree is available at http://www.webmproject.org/code
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87       This  manual  page  was  written  by  Pascal   Massimino   <pascal.mas‐
88       simino@gmail.com>, for the Debian project (and may be used by others).
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