Convert a gif image to webp
gif2webp [options] input_file.gif -o output_file.webp
This manual page documents the gif2webp command.
gif2webp converts a GIF image to a WebP image.
The basic options are:
-o string
Specify the name of the output WebP file. If omitted, gif2webp will perform conversion but only report statistics. Using "-" as output name will direct output to 'stdout'.
-h, -help
Usage information.
-version
Print the version number (as major.minor.revision) and exit.
-lossy
Encode the image using lossy compression.
-mixed
Mixed compression mode: optimize compression of the image by picking either lossy or lossless compression for each frame heuristically.
-q float
Specify the compression factor for RGB channels between 0 and 100. The default is 75.
In case of lossless compression (default), a small factor enables faster compression speed, but produces a larger file. Maximum compression is achieved by using a value of 100.
In case of lossy compression (specified by the -lossy option), a small factor produces a smaller file with lower quality. Best quality is achieved by using a value of 100.
-m int
Specify the compression method to use. This parameter controls the trade off between encoding speed and the compressed file size and quality. Possible values range from 0 to 6. Default value is 4. When higher values are used, the encoder will spend more time inspecting additional encoding possibilities and decide on the quality gain. Lower value can result is faster processing time at the expense of larger file size and lower compression quality.
-kmin int
-kmax int
Specify the minimum and maximum distance between consecutive key frames (independently decodable frames) in the output animation. The tool will insert some key frames into the output animation as needed so that this criteria is satisfied.
A 'kmin' value of 0 will turn off insertion of key frames. Typical values are in the range 3 to 30. Default values are kmin = 9, kmax = 17 for lossless compression and kmin = 3, kmax = 5 for lossy compression.
These two options are relevant only for animated images with large number of frames (>50).
When lower values are used, more frames will be converted to key frames. This may lead to smaller number of frames required to decode a frame on average, thereby improving the decoding performance. But this may lead to slightly bigger file sizes. Higher values may lead to worse decoding performance, but smaller file sizes.
Some restrictions:
(i) kmin < kmax,
(ii) kmin >= kmax / 2 + 1 and
(iii) kmax - kmin <= 30.
If any of these restrictions are not met, they will be enforced automatically.
-metadata string
A comma separated list of metadata to copy from the input to the output if present. Valid values: all, none, icc, xmp. The default is xmp.
-f int
For lossy encoding only (specified by the -lossy option). Specify the strength of the deblocking filter, between 0 (no filtering) and 100 (maximum filtering). A value of 0 will turn off any filtering. Higher value will increase the strength of the filtering process applied after decoding the picture. The higher the value the smoother the picture will appear. Typical values are usually in the range of 20 to 50.
-mt
Use multi-threading for encoding, if possible. This option is only effective when using lossy compression.
-v
Print extra information.
-quiet
Do not print anything.
Please report all bugs to our issue tracker: http://code.google.com/p/webp/issues
Patches welcome! See this page to get started: http://www.webmproject.org/code/contribute/submitting-patches/
gif2webp picture.gif -o picture.webp
gif2webp -q 70 picture.gif -o picture.webp
gif2webp -lossy -m 3 picture.gif -o picture_lossy.webp
gif2webp -lossy -f 50 picture.gif -o picture.webp
gif2webp -q 70 -o picture.webp -- ---picture.gif
gif2webp was written by the WebP team.
The latest source tree is available at http://www.webmproject.org/code
This manual page was written by Urvang Joshi <[email protected]>, for the Debian project (and may be used by others).
cwebp(1), dwebp(1), webpmux(1)
Please refer to http://developers.google.com/speed/webp/ for additional information.