USAGE: /usr/bin/tjbench [options] /usr/bin/tjbench [options] GENERAL OPTIONS (CAN BE ABBREVIATED) ------------------------------------ -alloc Dynamically allocate JPEG buffers -benchtime T Run each benchmark for at least T seconds [default = 5.0] -bmp Use Windows Bitmap format for output images [default = PPM or PGM] ** 8-bit data precision only ** -bottomup Use bottom-up row order for packed-pixel source/destination buffers -componly Stop after running compression tests. Do not test decompression. -lossless Generate lossless JPEG images when compressing (implies -subsamp 444). PSV is the predictor selection value (1-7). -maxmemory N Memory limit (in megabytes) for intermediate buffers used with progressive JPEG compression and decompression, Huffman table optimization, lossless JPEG compression, and lossless transformation [default = no limit] -maxpixels N Input image size limit (in pixels) [default = no limit] -noicc Do not transfer the embedded ICC profile (if any) from PNG input images or to PNG output images. -nowrite Do not write reference or output images (improves consistency of benchmark results) -pixelformat {rgb|bgr|rgbx|bgrx|xbgr|xrgb|gray} Use the specified pixel format for packed-pixel source/destination buffers [default = BGR] -pixelformat cmyk Indirectly test YCCK JPEG compression/decompression (use the CMYK pixel format for packed-pixel source/destination buffers) -png Use PNG format for output images [default = PPM or PGM] -precision N Use N-bit data precision when compressing [N = 2..16; default = 8; if N is not 8 or 12, then -lossless must also be specified] (-precision 12 implies -optimize unless -arithmetic is also specified) -quiet Output results in tabular rather than verbose format -restart N When compressing or transforming, add a restart marker every N MCU rows [default = 0 (no restart markers)]. Append 'B' to specify the restart marker interval in MCUs (lossy only.) -strict Immediately discontinue the current compression/decompression/transform operation if a warning (non-fatal error) occurs -tile Compress/transform the input image into separate JPEG tiles of varying sizes (useful for measuring JPEG overhead) -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 LOSSY JPEG OPTIONS (CAN BE ABBREVIATED) --------------------------------------- -arithmetic Use arithmetic entropy coding in JPEG images generated by compression and transform operations (can be combined with -progressive) -copy all Copy all extra markers (including comments, JFIF thumbnails, Exif data, and ICC profile data) when transforming the input image [default] -copy none Do not copy any extra markers when transforming the input image -crop WxH+X+Y Decompress only the specified region of the JPEG image, where W and H are the width and height of the region (0 = maximum possible width or height) and X and Y are the left and upper boundary of the region, all specified relative to the scaled image dimensions. X must be divible by the scaled iMCU width. -dct fast Use less accurate DCT/IDCT algorithm [legacy feature] -dct int Use more accurate DCT/IDCT algorithm [default] -flip {horizontal|vertical}, -rotate {90|180|270}, -transpose, -transverse 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) -maxscans N Refuse to decompress or transform progressive JPEG images that have more than N scans -nosmooth Use the fastest chrominance upsampling algorithm available -optimize Compute optimal Huffman tables for JPEG images generated by compession and transform operations -progressive Generate progressive JPEG images when compressing or transforming (can be combined with -arithmetic; implies -optimize unless -arithmetic is also specified) -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) -subsamp S When compressing, use the specified level of chrominance subsampling (S = 444, 422, 440, 420, 411, 441, 410, 24, or GRAY) [default = test Grayscale, 4:2:0, 4:2:2, and 4:4:4 in sequence] -yuv Compress from/decompress to intermediate planar YUV images ** 8-bit data precision only ** -yuvpad N The number of bytes by which each row in each plane of an intermediate YUV image is evenly divisible (N must be a power of 2) [default = 1] NOTE: If the quality/PSV is specified as a range (e.g. 90-100 or 1-4), a separate test will be performed for all values in the range.