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.

    unstable
        Allow the use of experimental new code. May subtly affect the output or even produce wrong results. For testing only.

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.

gamma (boolean)
    If value is set to 1, enable gamma correct scaling. Default value is 0.

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.