NAME

       tjbench - benchmark the performance of libjpeg-turbo

DESCRIPTION

       tjbench is a JPEG decompression/compression benchmark part of libjpeg-turbo.

USAGE

              tjbench <Inputimage (BMP|PPM)> <Quality> [options]

              tjbench <Inputimage (JPG)> [options]

OPTIONS

       -alloc  = Dynamically allocate JPEG buffers -bmp = Use Windows Bitmap format for output images [default =
       PPM]  -bottomup  =  Use  bottom-up  row  order  for  packed-pixel  source/destination  buffers  -tile   =
       Compress/transform the input image into separate JPEG tiles of varying

              sizes (useful for measuring JPEG overhead)

       -rgb, -bgr, -rgbx, -bgrx, -xbgr, -xrgb =

              Use the specified pixel format for packed-pixel source/destination buffers [default = BGR]

       -cmyk = Indirectly test YCCK JPEG compression/decompression

              (use the CMYK pixel format for packed-pixel source/destination buffers)

       -fastupsample  =  Use  the  fastest chrominance upsampling algorithm available -fastdct = Use the fastest
       DCT/IDCT  algorithm  available  -accuratedct  =  Use  the  most  accurate  DCT/IDCT  algorithm  available
       -progressive = Use progressive entropy coding in JPEG images generated by

              compression and transform operations

       -subsamp <s> = When compressing, use the specified level of chrominance

              subsampling  (<s> = 444, 422, 440, 420, 411, or GRAY) [default = test Grayscale, 4:2:0, 4:2:2, and
              4:4:4 in sequence]

       -quiet = Output results in tabular  rather  than  verbose  format  -yuv  =  Compress  from/decompress  to
       intermediate planar YUV images -yuvpad <p> = The number of bytes by which each row in each plane of an

              intermediate YUV image is evenly divisible (must be a power of 2) [default = 1]

       -scale M/N = When decompressing, scale the width/height of the JPEG image by a

              factor of M/N (M/N = 2/1, 15/8, 7/4, 13/8, 3/2, 11/8, 5/4, 9/8, 1/1, 7/8, 3/4, 5/8, 1/2, 3/8, 1/4,
              or 1/8)

       -hflip, -vflip, -transpose, -transverse, -rot90, -rot180, -rot270 =

              Perform  the  specified  lossless  transform  operation  on the input image prior to decompression
              (these operations are mutually exclusive)

       -grayscale = Transform the input image into a grayscale JPEG image prior to

              decompression (can be combined with the other transform operations above)

       -copynone = Do not copy any extra markers (including EXIF and ICC profile data)

              when transforming the input image

       -benchtime <t> = Run each benchmark for at least <t> seconds [default =  5.0]  -warmup  <t>  =  Run  each
       benchmark for <t> seconds [default = 1.0] prior to

              starting the timer, in order to prime the caches and thus improve the consistency of the benchmark
              results

       -componly  =  Stop  after running compression tests.  Do not test decompression.  -nowrite = Do not write
       reference or output images (improves consistency of

              benchmark results)

       -limitscans = Refuse to decompress or transform progressive JPEG images that

              have an unreasonably large number of scans

       -stoponwarning = Immediately discontinue the current

              compression/decompression/transform operation if a warning (non-fatal error) occurs

       NOTE:  If the quality is specified as a range (e.g. 90-100), a separate test will be  performed  for  all
       quality values in the range.

COMMENT

       This manual page was written by Mathieu Malaterre <malat@debian.org> for the Debian GNU/Linux system, but
       may be used by others.

COPYRIGHT

       Copyright (C)2009-2019, 2021 D. R. Commander.  All Rights Reserved.

tjbench 2.1.5                                      April 2024                                         TJBENCH(1)