1GIF2WEBP(1) General Commands Manual GIF2WEBP(1)
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6 gif2webp - Convert a GIF image to WebP
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9 gif2webp [options] input_file.gif -o output_file.webp
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12 This manual page documents the gif2webp command.
13 gif2webp converts a GIF image to a WebP image.
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17 The basic options are:
18 -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'.
23 -- 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.
30 -h, -help
32 Usage information.
33 -version
35 Print the version number (as major.minor.revision) and exit.
36 -lossy Encode the image using lossy compression.
38 -mixed Mixed compression mode: optimize compression of the image by
40 picking either lossy or lossless compression for each frame
41 heuristically.
42 -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.
52 -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.
61 -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.
67 -kmin int
69 -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.
95 -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.
100 -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.
108 -mt Use multi-threading for encoding, if possible.
110 -loop_compatibility
112 If enabled, handle the loop information in a compatible fashion
113 for Chrome version prior to M62 (inclusive) and Firefox.
114 -v Print extra information.
116 -quiet Do not print anything.
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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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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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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
140 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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146 cwebp(1), dwebp(1), webpmux(1)
147 Please refer to https://developers.google.com/speed/webp/ for addi‐
148 tional information.
149 November 17, 2021 GIF2WEBP(1)