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diff --git a/doc/fakeread.html b/doc/fakeread.html index aa2847c..2a7b5c0 100644 --- a/doc/fakeread.html +++ b/doc/fakeread.html @@ -1,248 +1,372 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> -<head> - <title>fakeread</title> - <meta http-equiv="content-type" - content="text/html; charset=ISO-8859-1"> - <meta name="author" content="Graeme Gill"> -</head> -<body> -<h2><b>spectro/fakeread</b></h2> -<h3>Summary</h3> -Simulate the measurement of a devices response, using an existing -device profile, or measured test point data set. The device profile can -be either -an <a href="File_Formats.html#ICC">ICC</a> or <a - href="File_Formats.html#MPP">MPP</a> profile, or the data set can be a -<a href="File_Formats.html#.ti3">.ti3</a> file. A device link -separation or color space conversion can be applied before the -print/measure simulation.<br> -<h3>Usage</h3> -<small><span style="font-family: monospace;">fakeread [-v] [-s] </span></small><small><span - style="font-family: monospace;">[<span style="font-style: italic;">separation.ic<span - style="font-family: monospace;">m</span></span>] </span></small><small><span - style="font-family: monospace;"></span><i - style="font-family: monospace;">profile.</i><span - style="font-family: monospace;">[icm|mpp|ti3] </span><i - style="font-family: monospace;">inoutfile</i><br - style="font-family: monospace;"> -<span style="font-family: monospace;"> -v + <head> + <title>fakeread</title> + <meta http-equiv="content-type" content="text/html; + charset=ISO-8859-1"> + <meta name="author" content="Graeme Gill"> + </head> + <body> + <h2><b>spectro/fakeread</b></h2> + <h3>Summary</h3> + Simulate the measurement of a devices response, using an existing + device profile, or measured test point data set. The device profile + can be either an <a href="File_Formats.html#ICC">ICC</a> or <a + href="File_Formats.html#MPP">MPP</a> profile, or the data set can + be a <a href="File_Formats.html#.ti3">.ti3</a> file. A device link + separation or color space conversion can be applied before the + print/measure simulation, as well as device calibration or + inverse calibration curves.<br> + <br> + <b>fakeread</b> can be useful for creating a data set from an + existing profile to re-create a different style of profile (i.e. + create a cLUT profile from a matrix profile), for creating synthetic + data sets with known amounts of randomness for testing profile + creation against a perfectly known ideal, or for creating + verification test sets for checking colorimetric colorspace + emulation against.<br> + <br> + The options below are in the order of color processing that fakeread + performs.<br> + <h3>Usage</h3> + <small><span style="font-family: monospace;">fakeread [-options] </span></small><small><span + style="font-family: monospace;"></span></small><small><span + style="font-family: monospace;"></span><i style="font-family: + monospace;">profile.</i><span style="font-family: monospace;">[icm|mpp|ti3] + + </span><i style="font-family: monospace;">inoutfile</i></small><small><span + style="font-family: monospace;"><br> + -v + [n] + Verbose mode [level]<br> + -e + flag + Video encode device input to sepration as:<br> + + n + normal 0..1 full range RGB levels (default)<br> + + t + (16-235)/255 "TV" RGB levels<br> + + 6 + Rec601 YCbCr SD (16-235,240)/255 "TV" levels<br> + + 7 + Rec709 1125/60Hz YCbCr HD (16-235,240)/255 "TV" levels<br> + + 5 + Rec709 1250/50Hz YCbCr HD (16-235,240)/255 "TV" levels<br> + + 2 + Rec2020 YCbCr UHD (16-235,240)/255 "TV" levels<br> + + C + Rec2020 Constant Luminance YCbCr UHD (16-235,240)/255 "TV" + levels<br> + -p <i>separation.icm</i> Use device link separation + profile on input<br> + -E + flag + Video decode separation device output. See -e above<br> + -k <i>file.cal</i> + Apply calibration (include in .ti3 output)<br> + -i <i>file.cal</i> + Include calibration in .ti3 output, but don't apply it<br> + -K <i>file.cal</i> + Apply inverse calibration<br> + -r + level Add + average random deviation of <level>% to device values + (after sep. & cal.)<br> + -0 + pow + Apply power to device chanel 0-9<br> + -b <i>output.icm</i> Apply + BT.1886-like mapping with effective gamma 2.2<br> + -b g.g:<i>output.icm</i> Apply BT.1886-like mapping with + effective gamma g.g<br> + -B <i>output.icm</i> Apply + BT.1886 mapping with technical gamma 2.4<br> + -B g.g:<i>output.icm</i> Apply BT.1886 mapping with + technical gamma g.g<br> + -I intent + r = relative colorimetric, a = absolute (default)<br> + -A + L,a,b + Scale black point to target Lab value<br> + -l + Output Lab rather than XYZ<br> + -s + Lookup </span></small><small><span style="font-family: + monospace;"><small><a style="font-family: monospace;" + href="File_Formats.html#MPP">MPP</a></small> + spectral values</span></small><br> + <small><span style="font-family: monospace;"><small><span + style="font-family: monospace;"> -R + level + Add average random deviation of <level>% to output PCS + values<br> + </span></small> -u + Make random deviations have uniform distributions rather than + normal<br> + -S + seed + Set random seed<br> + </span><span style="font-family: monospace;"> </span><i + style="font-family: monospace;">profile.</i><span + style="font-family: monospace;">[icm|mpp|ti3] </span><a + style="font-family: monospace;" href="File_Formats.html#ICC">ICC</a><span + style="font-family: monospace;">, </span><a style="font-family: + monospace;" href="File_Formats.html#MPP">MPP</a><span + style="font-family: monospace;"> or </span><a + style="font-family: monospace;" href="File_Formats.html#.ti3">.ti3</a><span + style="font-family: monospace;"> profile/file to use</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"></span><i + style="font-family: monospace;">inoutfile</i><span + style="font-family: monospace;"> - Verbose mode</span><br - style="font-family: monospace;"> -<span style="font-family: monospace;"> -s - Lookup </span><a style="font-family: monospace;" - href="File_Formats.html#MPP">MPP</a><span - style="font-family: monospace;"> spectral values</span><br - style="font-family: monospace;"> -<span style="font-family: monospace;"> -p -Use -separation profile</span><br style="font-family: monospace;"> -<span style="font-family: monospace;"> -l -Output -Lab rather than XYZ<br> - -k -file.cal -Apply -calibration (after sep.) and include in .ti3<br> - -i -file.cal -Include -calibration in .ti3 (but don't apply it)<br> -</span></small><small><span style="font-family: monospace;"> -r -level -Add -average random deviation of <level>% to input device values -(after sep. & cal.)</span></small><br - style="font-family: monospace;"> -<small><span style="font-family: monospace;"></span><span - style="font-family: monospace;"> -0 -pow -Apply -power to input device chanel 0-9 (after sep. cal. & rand.)</span><br - style="font-family: monospace;"> - -<span style="font-family: monospace;">-R -level -Add -average random deviation of <level>% to output PCS values<br> -</span></small><small><span style="font-family: monospace;"> -u - - -Make -random deviations have uniform distributions rather than normal<br> - -S -seed -Set -random seed<br style="font-family: monospace;"> -</span></small><small><span style="font-family: monospace;"></span><span - style="font-family: monospace;"> -b -L,a,b -Scale -black point to target Lab value<br> - -I -intent -r = relative colorimetric, a = absolute (default)<br - style="font-family: monospace;"> -</span><span style="font-family: monospace;"> [<span - style="font-style: italic;">separation.ic<span - style="font-family: monospace;">m</span></span>] -Device -link separation profile</span><br style="font-family: monospace;"> -<span style="font-family: monospace;"> </span><i - style="font-family: monospace;">profile.</i><span - style="font-family: monospace;">[icm|mpp|ti3] </span><a - style="font-family: monospace;" href="File_Formats.html#ICC">ICC</a><span - style="font-family: monospace;">, </span><a - style="font-family: monospace;" href="File_Formats.html#MPP">MPP</a><span - style="font-family: monospace;"> -or </span><a style="font-family: monospace;" - href="File_Formats.html#.ti3">.ti3</a><span - style="font-family: monospace;"> -profile/file to use</span><br style="font-family: monospace;"> - -<span style="font-family: monospace;"></span><i - style="font-family: monospace;">inoutfile</i><span - style="font-family: monospace;"> - - Base name for -input[</span><a style="font-family: monospace;" - href="File_Formats.html#.ti1">.ti1</a><span - style="font-family: monospace;">]/output[</span><a - style="font-family: monospace;" href="File_Formats.html#.ti3">.ti3</a><span - style="font-family: monospace;">] file</span></small><br> -<b><br> -Examples</b><br> -<br> -fakeread profile.icm testvalues<br> -fakeread -p separation.icm profile.icm testvalues<br> -<h3>Comments<br> -</h3> -The <span style="font-weight: bold;">-v</span> flag does nothing at -the moment.<br> -The <span style="font-weight: bold;">-s</span> flag works only with -MPP profiles that contain spectral model -information.<br> -The <span style="font-weight: bold;">-p</span> flag enables a device -to device value conversion before -converting to expected PCS values.<br> -The <span style="font-weight: bold;">-l</span> flag causes the CIE -output values to be L*a*b* rather than the -default XYZ values.<br> -<br> -The <b>-k file.cal</b> parameter specifies a printer -calibration file created by <a href="printcal.html">printcal</a>, and -the supplied calibration curves will be applied to the chart device -values after any separation. This allows emulating a system that uses -per device channel calibration. The calibration curves will also be -included in -the resulting .ti3 file, so that they can be passed through to the ICC -profile allowing accurate computation of ink -limits.<br> -<br> -<a name="i"></a> The <b>-i file.cal</b> parameter specifies a printer -calibration file created by <a href="printcal.html">printcal</a>, -and the calibration curves will be -included in the included in -the resulting .ti3 file, so that they can be passed through to the ICC -profile, to allow accurate computation of ink limits. -The calibration <span style="font-weight: bold;">is not applied</span> -to tchart values. <span style="font-weight: bold;">Note</span> that if -the supplied ICC profile contains calibration curves, that these will -be included in the resulting .ti3 by default.<br> -<span style="font-weight: bold;"></span><br> -The <span style="font-weight: bold;">-r</span> parameter is a way of -simulating instability in the behaviour of -the simulated -printing system. The parameter supplied to the flag will be used to -scale a random offset added to the device values (after any separation -and calibration is applied). The offset will be a normally distributed -error with an -average deviation of level%. A typically value supplied -might be 1.0 to simulate 1% randomness.<br> -<br> -The <span style="font-weight: bold;">-0, -1, -2 .. -9</span> -parameters are a way of simulating changes in the -behaviour of the simulated printing system. The parameter supplied to -the flag will be used to modify the device values (after any -separation, calibration and device randomness -is applied) by raising them to the power of the parameter. This applies -a transfer curve to the simulated device response.<br> -<br> -The <span style="font-weight: bold;">-R</span> parameter is a way of -simulating instability in the behaviour of -the simulated -measuring system. The parameter supplied to the flag will be used to -scale a random offset added to the PCS values. The offset will be a -normally distributed error with an average deviation of level%. A -typically value supplied -might be 1.0 to simulate 1% randomness. <br> -<br> -The <span style="font-weight: bold;">-u</span> flag changes the -distribution of the random offsets applied using the <span - style="font-weight: bold;">-r</span> or <span - style="font-weight: bold;">-R</span> flags, from the default standard -deviation, to a uniform deviation distribution. The level is still -specified as an average deviation.<br> -<br> -The <span style="font-weight: bold;">-S</span> parameter lets a -particular random seed be used when generating random offsets, so that -the randomness can be made repeatable. Normally a different seed will -be used for each run. <br> -<br> -The <span style="font-weight: bold;">-b</span> parameter is a way of -simulating devices that have a different black point to the profile -used. This only works if an ICC profile is used, and scales the black -point to the parameter value. This will be done in XYZ space by -default, and in L*a*b* space if the <span style="font-weight: bold;">-l</span> -flag is used.<br> -<br> -The <span style="font-weight: bold;">-I</span> parameter allows -changing the intent used in looking up the ICC profile colors to -relative colorimetric. This would <span - style="text-decoration: underline;">not</span> be used if you intend -to make a profile from the resulting .ti3 file, since profiles are -always made from absolute colorimetric measurement values. Note that -this flag does nothing if the profile is an MPP or .ti3 file.<br> -<br> -Fakeread is useful in creating artificial test value for testing <a - href="colprof.html">colprof</a>, as well as providing one path for -turning an MPP profile into an ICC profile. If a <a - href="File_Formats.html#.ti3">.ti3</a> file is -specified instead of an <a href="File_Formats.html#ICC">ICC</a> or <a - href="File_Formats.html#MPP">MPP</a> profile, -then the closest matching measured points in the .<a - href="File_Formats.html#.ti3">.ti3</a> are substituted -for the test values in the <a href="File_Formats.html#.ti1">.ti1</a> -file on -output. If the <a href="File_Formats.html#.ti1">.ti1</a> -file is a monochrome test file with a White device value, then an RGB <a - href="File_Formats.html#ICC">ICC</a> profile, <a - href="File_Formats.html#MPP">MPP</a> or <a - href="File_Formats.html#.ti3">.ti3</a> may be used, and the White -values will be translated to equal RGB values. If the <a - href="File_Formats.html#.ti1">.ti1</a> -file is a monochrome test file with a Black device value, then a CMYK <a - href="File_Formats.html#ICC">ICC</a> profile, <a - href="File_Formats.html#MPP">MPP</a> or <a - href="File_Formats.html#.ti3">.ti3</a> may be used, and the Black -values will be translated to equal CMY = 0, K = grey values. <span - style="font-weight: bold;">Note</span> that -any calibration within a supplied ICC profile is <span - style="text-decoration: underline;">not</span> applied during the -conversion, although it will be included in the .ti3 output (see <span - style="font-weight: bold;">-k</span> and <span - style="font-weight: bold;">-i</span> flags for how apply calibration -curves during the conversion and/or include -a specific calibration curves in the output).<br> -<br> -If a separation device profile is provided (e.g. from CMY -> CMYK, -or perhaps CMYK->CMYK, to simulate a color correction step before -"printing"), then this will be applied to the .ti1 device values, -before converting the the device values into .ti3 PCS values.<br> -<br> -<br> -<br> -</body> + + + Base name for input[</span><a style="font-family: + monospace;" href="File_Formats.html#.ti1">.ti1</a><span + style="font-family: monospace;">]/output[</span><a + style="font-family: monospace;" href="File_Formats.html#.ti3">.ti3</a><span + style="font-family: monospace;">] file</span></small><br> + <b><br> + Examples</b><br> + <br> + fakeread profile.icm testvalues<br> + fakeread -p separation.icm profile.icm testvalues<br> + <h3>Comments<br> + </h3> + <a name="v"></a>The <span style="font-weight: bold;">-v</span> flag + reports extra information, e.g. on what BT.1886 option is doing. A + level > 1 will be more verbose.<br> + <br> + <a name="e"></a>The <b>-e</b> <i>flag</i> applies a Video encoding + to the input of the separation.<small><small><br> + <br> + + n + normal 0..1 full range RGB levels (default)<br> + + t + (16-235)/255 "TV" RGB levels<br> + + 6 + Rec601 YCbCr SD (16-235,240)/255 "TV" levels<br> + + 7 + Rec709 1125/60Hz YCbCr HD (16-235,240)/255 "TV" levels<br> + + 5 + Rec709 1250/50Hz YCbCr HD (16-235,240)/255 "TV" levels<br> + + 2 + Rec2020 YCbCr UHD (16-235,240)/255 "TV" levels<br> + + C + Rec2020 Constant Luminance YCbCr UHD (16-235,240)/255 "TV" lev</small></small><br> + <br> + <a name="p"></a>The <span style="font-weight: bold;">-p</span> <b><i>separation.icm</i></b> + option enables a device to device value conversion before converting + to expected PCS values. This might be an ink separation of a video + calibration device link. The argument is the name of the ICC device + link that defines the separation.<br> + <br> + <a name="E"></a>The <b>-E</b> <i>flag</i> applies a Video decoding + to the output of the separation.<small><small> </small></small>See + <a href="#e"><b>-e</b></a> for the list of decodings.<br> + <br> + <a name="k"></a>The <b>-k file.cal</b> parameter specifies a + calibration file created by <a + href="printcal.html">printcal</a> or <a + href="dispcal.html">dispcal</a>, and the supplied calibration + curves will be applied to the chart device values after any + separation and before the device profile. This allows emulating a + system that uses per device channel calibration. The calibration + curves will also be included in the resulting .ti3 file, so that + they can be passed through to the ICC profile allowing accurate + computation of ink limits.<br> + <br> + <a name="i"></a> The <b>-i file.cal</b> parameter specifies a + printer calibration file created by <a + href="printcal.html">printcal</a> or <a + href="dispcal.html">dispcal</a>, and the + calibration curves will be included in the included in the resulting + .ti3 file, so that they can be passed through to the ICC profile, to + allow accurate computation of ink limits. The calibration <span + style="font-weight: bold;">is not applied</span> to tchart values. + <span style="font-weight: bold;">Note</span> that if the supplied + ICC profile contains VCGT calibration curves, that these will be + included in the resulting .ti3 by default.<br> + <br> + <a name="K"></a>The <b>-K</b> <b>file.cal</b> parameter specifies + a calibration file created by <a + href="printcal.html">printcal</a> or <a + href="dispcal.html">dispcal</a>, and the + inverse of the supplied calibration curves will be applied to the + chart device values after any separation and before the device + profile. This allows for undoing calibration curves that may be part + of a video calibration device link, so that the (calibrated device + value) device profile will work as expected.<br> + <br> + <a name="r"></a>The <span style="font-weight: bold;">-r</span> + parameter is a way of simulating instability in the behaviour of the + simulated printing system. The parameter supplied to the flag will + be used to scale a random offset added to the device values (after + any separation and calibration is applied). The offset will be a + normally distributed error with an average deviation of level%. A + typically value supplied might be 1.0 to simulate 1% randomness.<br> + <br> + <a name="0"></a>The <span style="font-weight: bold;">-0, -1, -2 .. + -9</span> parameters are a way of simulating changes in the + behavior of the simulated printing system. The parameter supplied to + the flag will be used to modify the device values (after any + separation, calibration and device randomness is applied) by raising + them to the power of the parameter. This applies a transfer curve to + the simulated device response.<br> + <br> + <a name="b"></a>The <b>-b output.icm</b> flag applies extra input + processing, applying <a + href="http://www.itu.int/rec/R-REC-BT.1886-0-201103-I">BT.1886</a>-like + + + + + + + + + + + + video gamma mapping using an effective gamma of 2.2 by default, and + overridable using <b>-b g.g:output.icm</b> where <b>g.g</b> is the + gamma. <b>output.icm</b> is the display ICC profile that provides + the black point that the BT.1886 curves will target. The gamma is an + effective gamma, meaning that its effect on 50% input is the same as + that of a pure power curve, in spite of any black offset added by + BT.1886. This has the benefit of making the overall effect of + brightness independent of the black level of the display. Setting an + effective gamma other than 2.2 is one way of making the viewing + condition adjustment for the different conditions of video encoding + and decoding, or for modelling the source colorspace as a rendering + on a video display. BT.1886 will only work with matrix type input + profiles. Typically this will be used to create a verification test + set for checking the operation of a device link or 3dLut created + using <a href="collink.html">collink</a>, using the same BT.1886 + parameters.<br> + <br> + <b><a name="B"></a></b>The <b>-B output.icm</b> flag applies extra + input processing, applying <a + href="http://www.itu.int/rec/R-REC-BT.1886-0-201103-I">BT.1886</a>-like + + + + + + + + + + + + video gamma mapping using a gamma of 2.4 by default, and overridable + using <b>-B g.g:output.icm</b> where <b>g.g</b> is the gamma. <b>output.icm</b> + is the display ICC profile that provides the black point that the + BT.1886 curves will target. The gamma is the technical gamma, or + power applied to the input image, and this means that its effect on + 50% input will depend on the black level of the display, making the + overall brightness somewhat unpredictable. For a more predictable + effect, use <b>-b</b>.<br> + <br> + <a name="I"></a>The <span style="font-weight: bold;">-I</span> + parameter allows changing the intent used in looking up the ICC + profile colors to relative colorimetric. This would <span + style="text-decoration: underline;">not</span> be used if you + intend to make a profile from the resulting .ti3 file, since + profiles are always made from absolute colorimetric measurement + values. Note that this flag does nothing if the profile is an MPP or + .ti3 file.<br> + <span style="font-weight: bold;"></span><br> + <a name="A"></a>The <span style="font-weight: bold;">-A</span> + parameter is a way of simulating devices that have a different black + point to the profile used. This only works if an ICC profile is + used, and scales the black point to the parameter value. This will + be done in XYZ space by default, and in L*a*b* space if the <a + href="#l"><span style="font-weight: bold;">-l</span></a> flag is + used.<br> + <br> + <a name="l"></a>The <span style="font-weight: bold;">-l</span> flag + causes the CIE output values to be L*a*b* rather than the default + XYZ values.<br> + <br> + <a name="s"></a>The <span style="font-weight: bold;">-s</span> flag + works if a spectral MPP file is being used as a device profile, and + causes the output to include spectral values.<br> + <br> + <a name="R"></a>The <span style="font-weight: bold;">-R</span> + parameter is a way of simulating instability in the behavior of the + simulated measuring system. The parameter supplied to the flag will + be used to scale a random offset added to the PCS values. The offset + will be a normally distributed error with an average deviation of + level%. A typically value supplied might be 1.0 to simulate 1% + randomness. <br> + <br> + <a name="u"></a>The <span style="font-weight: bold;">-u</span> flag + changes the distribution of the random offsets applied using the <span + style="font-weight: bold;">-r</span> or <span style="font-weight: + bold;">-R</span> flags, from the default standard deviation, to a + uniform deviation distribution. The level is still specified as an + average deviation.<br> + <br> + <a name="S"></a>The <span style="font-weight: bold;">-S</span> + parameter lets a particular random seed be used when generating + random offsets, so that the randomness can be made repeatable. + Normally a different seed will be used for each run. <br> + <br> + Fakeread is useful in creating artificial test value for testing <a + href="colprof.html">colprof</a>, as well as providing one path for + turning an MPP profile into an ICC profile. It can also be used to + create a reference file for verifying against. If a <a + href="File_Formats.html#.ti3">.ti3</a> file is specified instead + of an <a href="File_Formats.html#ICC">ICC</a> or <a + href="File_Formats.html#MPP">MPP</a> profile, then the closest + matching measured points in the .<a href="File_Formats.html#.ti3">.ti3</a> + are substituted for the test values in the <a + href="File_Formats.html#.ti1">.ti1</a> file on output. If the <a + href="File_Formats.html#.ti1">.ti1</a> file is a monochrome test + file with a White device value, then an RGB <a + href="File_Formats.html#ICC">ICC</a> profile, <a + href="File_Formats.html#MPP">MPP</a> or <a + href="File_Formats.html#.ti3">.ti3</a> may be used, and the White + values will be translated to equal RGB values. If the <a + href="File_Formats.html#.ti1">.ti1</a> file is a monochrome test + file with a Black device value, then a CMYK <a + href="File_Formats.html#ICC">ICC</a> profile, <a + href="File_Formats.html#MPP">MPP</a> or <a + href="File_Formats.html#.ti3">.ti3</a> may be used, and the Black + values will be translated to equal CMY = 0, K = grey values. <span + style="font-weight: bold;">Note</span> that any calibration within + a supplied ICC profile is <span style="text-decoration: underline;">not</span> + applied during the conversion, although it will be included in the + .ti3 output (see <span style="font-weight: bold;">-k</span> and <span + style="font-weight: bold;">-i</span> flags for how apply + calibration curves during the conversion and/or include a specific + calibration curves in the output).<br> + <br> + If a separation device profile is provided (e.g. from CMY -> + CMYK, or perhaps CMYK->CMYK, to simulate a color correction step + before "printing", or perhaps a Video RGB->RGB calibration link) + then this will be applied to the .ti1 device values, before + converting the the device values into .ti3 PCS values.<br> + <br> + <br> + <br> + <br> + </body> </html> |