pamhomography(1) General Commands Manual pamhomography(1) (NAME) pamhomography - / (SYNOPSIS) pamhomography [-from=coords] [-to=coords] [-mapfile=map_file] [-view=coords] [-fill=color] [-verbose [pam_file] . . = (whitespace) . (DESCRIPTION) Netpbm . pamhomography ( ) . (affine) : () () / (shearing/skewing). pamhomography (bilinear) () . . (OPTIONS) libnetpbm ( -quiet (Common Options) ) pamhomography : -from=coords . coords (x, y) . -from -mapfile . -to=coords . coords (x, y) . -to -mapfile . -mapfile=map_file . map_file (x, y) (x, y) . - . -to -from . -view=coords . coords (x, y) : - - . -view . -fill=color . pnm_parsecolor() . (transparency plane) . -verbose . . : . . (PARAMETERS) pamhomography pam_file . pam_file . (NOTES) Netpbm . Netpbm << >> (SEE ALSO) <#SEE-ALSO> . pamhomography (shearing) . (EXAMPLES) park_row.ppm (Park Row Building) x PPM GFDL . (bilinear) . park_row_rect.map : (0, 0) (440, 0) (440, 639) (0, 639) . pamhomography park_row_rect.map . : . pamhomography : () . (0, 0) ↔ (440, 0) (0, 639) ↔ (639, 0). . x x : (tan) . -view -fill : : -view : -from -to : . . \((x_1, y_1)\) \((x_2, y_2)\) \((x_3, y_3)\) \((x_4, y_4)\) \(\theta\) \((c_x, c_y)\) : \[ \begin{bmatrix} 1 & 0 & c_x \\ 0 & 1 & c_y \\ 0 & 0 & 1 \end{bmatrix} \begin{bmatrix} \cos \theta & -\sin \theta & 0 \\ \sin \theta & \cos \theta & 0 \\ 0 & 0 & 1 \end{bmatrix} \begin{bmatrix} 1 & 0 & -c_x \\ 0 & 1 & -c_y \\ 0 & 0 & 1 \end{bmatrix} \begin{bmatrix} x_1 & x_2 & x_3 & x_4 \\ y_1 & y_2 & y_3 & y_4 \\ 1 & 1 & 1 & 1 \end{bmatrix} \quad. \] park_row.ppm (220, 320) : \[ \begin{bmatrix} 1 & 0 & 220 \\ 0 & 1 & 320 \\ 0 & 0 & 1 \end{bmatrix} \begin{bmatrix} \cos 30^{\circ} & -\sin 30^{\circ} & 0 \\ \sin 30^{\circ} & \cos 30^{\circ} & 0 \\ 0 & 0 & 1 \end{bmatrix} \begin{bmatrix} 1 & 0 & -220 \\ 0 & 1 & -320 \\ 0 & 0 & 1 \end{bmatrix} \begin{bmatrix} 0 & 440 & 440 & 0 \\ 0 & 0 & 639 & 639 \\ 1 & 1 & 1 & 1 \end{bmatrix} = \begin{bmatrix} 189.4744 & 570.5256 & 251.0256 & -130.0256 \\ -67.1281 & 152.8719 & 706.2621 & 486.2621 \\ 1.0000 & 1.0000 & 1.0000 & 1.0000 \end{bmatrix} \quad, \] (transpose) park_row_rot30.map : 571 153 251 706 -130 486 ( 'to' 'from' .) : (SEE ALSO) o pamcut(1) o pamenlarge(1) o pamflip(1) o pamperspective(1) o pamscale(1) o pamstretch(1) o pam(1) o pnmmargin(1) o pnmpad(1) o pnmrotate(1) o pnmshear(1) (HISTORY) pamhomography Netpbm 10.94 ( 2021) . (AUTHOR) (C) (Scott Pakin) scott+pbm@pakin.org (Table of Contents) o (SYNOPSIS) <#SYNOPSIS> o (DESCRIPTION) <#DESCRIPTION> o (OPTIONS) <#OPTIONS> o (PARAMETERS) <#PARAMETERS> o (NOTES) <#NOTES> o (EXAMPLES) <#EXAMPLES> o (SEE ALSO) <#SEE-ALSO> o (HISTORY) <#HISTORY> o (AUTHOR) <#AUTHOR> (DOCUMENT SOURCE) Netpbm 'makeman' HTML . : http://netpbm.sourceforge.net/doc/pamhomography.html netpbm documentation 04 December 2022 pamhomography(1)