Name
img2webp
-- Create animated WebP file from a sequence of input images.
Synopsis
img2webp [file_options] [[frame_options] frame_file]...
img2webp argument_file_name
Description
img2webp
compresses a sequence of images using the animated WebP format. Input
images can either be PNG, JPEG, TIFF or WebP. If a single file name (not
starting with the character '-') is supplied as the argument, the command line
arguments are actually tokenized from this file. This allows for easy scripting
or using a large number of arguments.
File-level Options
The file-level options are applied at the beginning of the compression process, before the input frames are read.
-o string
- Specify the name of the output WebP file.
-min_size
- Encode images to achieve smallest size. This disables key frame insertion
and picks the parameters resulting in the smallest output for each frame. It
uses lossless compression by default, but can be combined with
-q
,-m
,-lossy
or-mixed
options. -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.
-mixed
- Mixed compression mode: optimize compression of the image by picking either
lossy or lossless compression for each frame heuristically. This global
option disables the local option
-lossy
and-lossless
. -near_lossless int
- Specify the level of near-lossless image preprocessing. This option adjusts
pixel values to help compressibility, but has minimal impact on the visual
quality. It triggers lossless compression mode automatically. The range is 0
(maximum preprocessing) to 100 (no preprocessing, the default). The typical
value is around 60. Note that lossy with
-q 100
can at times yield better results. -sharp_yuv
- Use more accurate and sharper RGB->YUV conversion. Note that this process is slower than the default 'fast' RGB->YUV conversion.
-loop int
- Specifies the number of times the animation should loop. Using
0
means 'loop indefinitely'. -v
- Be more verbose.
-h, -help
- A short usage summary.
-version
- Print the version numbers of the relevant libraries used.
Per-frame Options
The per-frame options are applied for the images following as arguments in the command line. They can be modified any number of times preceding each particular input image.
-d int
- Specify the image duration in milliseconds.
-lossless, -lossy
- Compress the next image(s) using lossless or lossy compression mode. The default mode is lossless.
-q float
- Specify the compression factor between 0 and 100. The default is 75.
-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 in faster processing time at the expense of larger file size and lower compression quality.
Bugs
Please report all bugs to the issue tracker: https://issues.webmproject.org
Patches welcome! See this page to get started: https://www.webmproject.org/code/contribute/submitting-patches/
Example
img2webp -loop 2 in0.png -lossy in1.jpg -d 80 in2.tiff -o out.webp
Authors
img2webp
is a part of libwebp
and was written by the WebP team. The latest
source tree is available at https://chromium.googlesource.com/webm/libwebp
This manual page was written by Pascal Massimino pascal.massimino@gmail.com for the Debian project (and may be used by others).