1GIF2WEBP(1)                 General Commands Manual                GIF2WEBP(1)
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NAME

6       gif2webp - Convert a GIF image to WebP
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SYNOPSIS

9       gif2webp [options] input_file.gif -o output_file.webp
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DESCRIPTION

12       This manual page documents the gif2webp command.
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14       gif2webp converts a GIF image to a WebP image.
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OPTIONS

17       The basic options are:
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19       -o string
20              Specify  the  name of the output WebP file. If omitted, gif2webp
21              will perform conversion but only report statistics.   Using  "-"
22              as output name will direct output to 'stdout'.
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24       -- string
25              Explicitly  specify the input file. This option is useful if the
26              input file starts with an '-' for instance. This option must ap‐
27              pear  last.  Any other options afterward will be ignored. If the
28              input file is "-", the data will be read from stdin instead of a
29              file.
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31       -h, -help
32              Usage information.
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34       -version
35              Print the version number (as major.minor.revision) and exit.
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37       -lossy Encode the image using lossy compression.
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39       -mixed Mixed  compression  mode:  optimize  compression of the image by
40              picking either lossy or  lossless  compression  for  each  frame
41              heuristically.
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43       -q float
44              Specify  the  compression  factor for RGB channels between 0 and
45              100. The default is 75.
46              In case of lossless compression (default), a  small  factor  en‐
47              ables faster compression speed, but produces a larger file. Max‐
48              imum compression is achieved by using a value of 100.
49              In case of lossy compression (specified by the -lossy option), a
50              small  factor  produces  a smaller file with lower quality. Best
51              quality is achieved by using a value of 100.
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53       -m int Specify the compression method to use. This  parameter  controls
54              the  trade  off  between  encoding speed and the compressed file
55              size and quality.  Possible values range from 0  to  6.  Default
56              value is 4.  When higher values are used, the encoder will spend
57              more time inspecting additional encoding possibilities  and  de‐
58              cide on the quality gain.  Lower value can result is faster pro‐
59              cessing time at the expense of larger file size and  lower  com‐
60              pression quality.
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62       -min_size
63              Encode  image  to achieve smallest size. This disables key frame
64              insertion and picks the dispose method resulting in the smallest
65              output  for each frame. It uses lossless compression by default,
66              but can be combined with -q, -m, -lossy or -mixed options.
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68       -kmin int
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70       -kmax int
71              Specify the minimum and maximum distance between consecutive key
72              frames (independently decodable frames) in the output animation.
73              The tool will insert some key frames into the  output  animation
74              as needed so that this criteria is satisfied.
75              A  'kmax'  value  of  0 will turn off insertion of key frames. A
76              'kmax' value of 1 will result in all frames  being  key  frames.
77              'kmin'  value  is  not  taken into account in both these special
78              cases.  Typical values are in the range 3 to 30. Default  values
79              are  kmin  = 9, kmax = 17 for lossless compression and kmin = 3,
80              kmax = 5 for lossy compression.
81              These two options are relevant only  for  animated  images  with
82              large number of frames (>50).
83              When lower values are used, more frames will be converted to key
84              frames. This may lead to smaller number of  frames  required  to
85              decode  a  frame on average, thereby improving the decoding per‐
86              formance. But this may  lead  to  slightly  bigger  file  sizes.
87              Higher  values  may  lead  to  worse  decoding  performance, but
88              smaller file sizes.
89              Some restrictions:
90              (i) kmin < kmax,
91              (ii) kmin >= kmax / 2 + 1 and
92              (iii) kmax - kmin <= 30.
93              If any of these restrictions are not met, they will be  enforced
94              automatically.
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96       -metadata string
97              A comma separated list of metadata to copy from the input to the
98              output if present.  Valid values: all, none, icc, xmp.  The  de‐
99              fault is xmp.
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101       -f int For  lossy encoding only (specified by the -lossy option). Spec‐
102              ify the strength of the deblocking filter, between 0 (no filter‐
103              ing)  and  100  (maximum filtering).  A value of 0 will turn off
104              any filtering. Higher value will increase the  strength  of  the
105              filtering process applied after decoding the picture. The higher
106              the value the smoother the picture will appear.  Typical  values
107              are usually in the range of 20 to 50.
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109       -mt    Use multi-threading for encoding, if possible.
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111       -loop_compatibility
112              If  enabled, handle the loop information in a compatible fashion
113              for Chrome version prior to M62 (inclusive) and Firefox.
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115       -v     Print extra information.
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117       -quiet Do not print anything.
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119

BUGS

121       Please    report     all     bugs     to     the     issue     tracker:
122       https://bugs.chromium.org/p/webp
123       Patches  welcome!  See  this  page to get started: https://www.webmpro
124       ject.org/code/contribute/submitting-patches/
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EXAMPLES

128       gif2webp picture.gif -o picture.webp
129       gif2webp -q 70 picture.gif -o picture.webp
130       gif2webp -lossy -m 3 picture.gif -o picture_lossy.webp
131       gif2webp -lossy -f 50 picture.gif -o picture.webp
132       gif2webp -q 70 -o picture.webp -- ---picture.gif
133       cat picture.gif | gif2webp -o - -- - > output.webp
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AUTHORS

137       gif2webp is a part of libwebp and was written by the WebP team.
138       The  latest  source  tree  is  available  at   https://chromium.google
139       source.com/webm/libwebp
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141       This  manual  page was written by Urvang Joshi <urvang@google.com>, for
142       the Debian project (and may be used by others).
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SEE ALSO

146       cwebp(1), dwebp(1), webpmux(1)
147       Please refer  to  https://developers.google.com/speed/webp/  for  addi‐
148       tional information.
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152                               November 17, 2021                   GIF2WEBP(1)
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