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. scaler, scaler_sub Choose the scaling algorithm to use. Default value is auto for both. It accepts the following values: auto Aumotic choice. For scaler_sub, this means the same algorithm as scaler. For scaler, this defaults to the scaler flag selected by sws_flags. bilinear Bilinear filter. (AKA triangle filter) bicubic 2-tap cubic BC-spline (AKA Mitchell-Netravali spline). The B and C parameters can be configured by setting "param0" and "param1", defaulting to 0.0 and 0.6 respectively. point, neighbor Point sampling (AKA nearest neighbor). area Area averaging. Equivalent to bilinear for upscaling. gaussian 2-tap Gaussian filter approximation. The sharpness parameter can be configured by setting "param0", defaulting to 3.0. sinc Unwindowed sinc filter. lanczos Lanczos resampling (sinc windowed sinc). The number of filter taps can be configured by setting "param0", defaulting to 3. spline Unwindowed natural bicubic spline. sws_flags Set the scaler flags. This is also used to set the scaling algorithm, though this usage is deprecated in favor of setting scaler. Only a single algorithm may be selected. Default value is bicubic. It accepts the following values: fast_bilinear Select fast bilinear scaling algorithm. (Deprecated) bilinear Select bilinear scaling algorithm. (Deprecated) bicubic Select bicubic scaling algorithm. (Deprecated) experimental Select experimental scaling algorithm. (Deprecated) neighbor Select nearest neighbor rescaling algorithm. (Deprecated) area Select averaging area rescaling algorithm. (Deprecated) bicublin Select bicubic scaling algorithm for the luma component, bilinear for chroma components. (Deprecated) gauss Select Gaussian rescaling algorithm. (Deprecated) sinc Select sinc rescaling algorithm. (Deprecated) lanczos Select Lanczos rescaling algorithm. The default width (alpha) is 3 and can be changed by setting "param0". (Deprecated) spline Select natural bicubic spline rescaling algorithm. (Deprecated) 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 sws_backends Set the allowed swscale backends. This is a flags option, so multiple backends may be combined. auto Automatic selection. Equal to either stable or all depending on whether or not the unstable flag is set. This is the default value. stable All stable backends. unstable All unstable backends. all All available backends. legacy Legacy swscale code. c Template-based reference code. memcpy Fast path using libc "memcpy". x86 x86 SIMD kernels. aarch64 AArch64 NEON kernels. spirv Vulkan SPIR-V backend. 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 . Maintainers for the specific components are listed in the file MAINTAINERS in the source code tree. FFMPEG-SCALER(1)