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FFMPEG-SCALER(1) FFMPEG-SCALER(1)
NAME
ffmpeg-scaler - FFmpeg video scaling and pixel format converter
DESCRIPTION
The FFmpeg rescaler provides a high-level interface to the libswscale
library image conversion utilities. In particular it allows one to
perform image rescaling and pixel format conversion.
SCALER OPTIONS
The video scaler supports the following named options.
Options may be set by specifying -option value in the FFmpeg tools,
with a few API-only exceptions noted below. For programmatic use, they
can be set explicitly in the "SwsContext" options or through the
libavutil/opt.h API.
sws_flags
Set the scaler flags. This is also used to set the scaling
algorithm. Only a single algorithm should be selected. Default
value is bicubic.
It accepts the following values:
fast_bilinear
Select fast bilinear scaling algorithm.
bilinear
Select bilinear scaling algorithm.
bicubic
Select bicubic scaling algorithm.
experimental
Select experimental scaling algorithm.
neighbor
Select nearest neighbor rescaling algorithm.
area
Select averaging area rescaling algorithm.
bicublin
Select bicubic scaling algorithm for the luma component,
bilinear for chroma components.
gauss
Select Gaussian rescaling algorithm.
sinc
Select sinc rescaling algorithm.
lanczos
Select Lanczos rescaling algorithm. The default width (alpha)
is 3 and can be changed by setting "param0".
spline
Select natural bicubic spline rescaling algorithm.
print_info
Enable printing/debug logging.
accurate_rnd
Enable accurate rounding.
full_chroma_int
Enable full chroma interpolation.
full_chroma_inp
Select full chroma input.
bitexact
Enable bitexact output.
srcw (API only)
Set source width.
srch (API only)
Set source height.
dstw (API only)
Set destination width.
dsth (API only)
Set destination height.
src_format (API only)
Set source pixel format (must be expressed as an integer).
dst_format (API only)
Set destination pixel format (must be expressed as an integer).
src_range (boolean)
If value is set to 1, indicates source is full range. Default value
is 0, which indicates source is limited range.
dst_range (boolean)
If value is set to 1, enable full range for destination. Default
value is 0, which enables limited range.
param0, param1
Set scaling algorithm parameters. The specified values are specific
of some scaling algorithms and ignored by others. The specified
values are floating point number values.
sws_dither
Set the dithering algorithm. Accepts one of the following values.
Default value is auto.
auto
automatic choice
none
no dithering
bayer
bayer dither
ed error diffusion dither
a_dither
arithmetic dither, based using addition
x_dither
arithmetic dither, based using xor (more random/less apparent
patterning that a_dither).
alphablend
Set the alpha blending to use when the input has alpha but the
output does not. Default value is none.
uniform_color
Blend onto a uniform background color
checkerboard
Blend onto a checkerboard
none
No blending
SEE ALSO
ffmpeg(1), ffplay(1), ffprobe(1), libswscale(3)
AUTHORS
The FFmpeg developers.
For details about the authorship, see the Git history of the project
(https://git.ffmpeg.org/ffmpeg), e.g. by typing the command git log in
the FFmpeg source directory, or browsing the online repository at
<https://git.ffmpeg.org/ffmpeg>.
Maintainers for the specific components are listed in the file
MAINTAINERS in the source code tree.
FFMPEG-SCALER(1)