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diff --git a/doc/scanin.html b/doc/scanin.html new file mode 100644 index 0000000..db5091f --- /dev/null +++ b/doc/scanin.html @@ -0,0 +1,582 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<html> + <head> + <title>scanin</title> + <meta http-equiv="content-type" content="text/html; + charset=ISO-8859-1"> + <meta name="author" content="Graeme Gill"> + </head> + <body> + <h2><b>scanin/scanin</b></h2> + <h3>Summary</h3> + Convert an 8 or 16 bit per component <a + href="File_Formats.html#TIFF">TIFF</a> + image of a + test chart into <a href="File_Formats.html#.ti3">.ti3</a> + device + values + using automatic pattern recognition, or manual chart alignment.<br> + Performs other tasks associated with turning a TIFF raster of test + patches into numeric values. <br> + <h3>Usage Summary<br> + </h3> + <small><a style="font-family: monospace;" href="#_"> usage</a><span + style="font-family: monospace;">: scanin [options] input.tif + recogin.cht + valin.cie [diag.tif]</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> :- inputs + 'input.tif', and outputs scanner + 'input.ti3', or</span><br style="font-family: monospace;"> + <br style="font-family: monospace;"> + <a style="font-family: monospace;" href="#g"> usage</a><span + style="font-family: monospace;">: scanin -g [options] input.tif + recogout.cht + [diag.tif]</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> :- outputs file + 'recogout.cht', or</span><br style="font-family: monospace;"> + <br style="font-family: monospace;"> + <a style="font-family: monospace;" href="#o"> usage</a><span + style="font-family: monospace;">: scanin -o [options] input.tif + recogin.cht + [diag.tif]</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> :- outputs file + 'input.val', or</span><br style="font-family: monospace;"> + <br style="font-family: monospace;"> + <a style="font-family: monospace;" href="#c"> usage</a><span + style="font-family: monospace;">: scanin -c [options] input.tif + recogin.cht + scanprofile.[icm|mpp] pbase [diag.tif]</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> :- inputs + pbase.ti2 + and outputs printer pbase.ti3, or</span><br style="font-family: + monospace;"> + <br style="font-family: monospace;"> + <a style="font-family: monospace;" href="#r"> usage</a><span + style="font-family: monospace;">: scanin -r [options] input.tif + recogin.cht + pbase [diag.tif]</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> :- inputs + pbase.ti2+.ti3 and outputs pbase.ti3</span><br + style="font-family: monospace;"> + <br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#g">-g</a><span + style="font-family: monospace;"> +Generate + a chart reference (.cht) file</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#o">-o</a><span + style="font-family: monospace;"> +Output + patch values in .val file</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#c">-c</a><span + style="font-family: monospace;"> +Use + image to measure color to convert printer pbase .ti2 to .ti3</span><span + style="font-family: monospace;"></span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#ca">-ca</a><span + style="font-family: monospace;"> +Same + as -c, but accumulates more values to pbase .ti3</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> +from + subsequent pages</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#r">-r</a><span + style="font-family: monospace;"> +Replace + device values in pbase .ti3</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> +Default + is to create a scanner .ti3 file<br> + </span></small><small><span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#F">-F + x1,y1,x2,y2,x3,y3,x4,y4</a><span style="font-family: monospace;"> + <br> + +Don't + auto recognize, locate using four fiducual marks<br> + <a href="#p">-p</a> +Compensate + for perspective distortion<br style="font-family: monospace;"> + </span></small><small><span style="font-family: monospace;"></span><span + style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#a">-a</a><span + style="font-family: monospace;"> +Recognize + chart in normal orientation only</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> +Default + is to recognize all possible chart angles<br> + <a href="#m">-m</a> +Return + true mean (default is robust mean)<br> + </span></small><small><span style="font-family: monospace;"> <a + href="#G">-G gamma</a> + +Approximate +gamma + encoding of image</span></small><br style="font-family: + monospace;"> + <small><span style="font-family: monospace;"></span><span + style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#v">-v [n]</a><span + style="font-family: monospace;"> +Verbosity + level 0-9</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#d">-d</a><span + style="font-family: monospace;"> [ihvglLIcrsonap] + generate + diagnostic output (try -dipn)</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#di">i</a><span + style="font-family: monospace;"> +diag + - B&W of input image</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#dh">h</a><span + style="font-family: monospace;"> +diag + - Horizontal edge detection</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#dv">v</a><span + style="font-family: monospace;"> +diag + - Vertical edge detection</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#dg">g</a><span + style="font-family: monospace;"> +diag + - Groups detected</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#dl">l</a><span + style="font-family: monospace;"> +diag + - Lines detected</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#dL">L</a><span + style="font-family: monospace;"> +diag + - All lines detected<br> + </span></small><small><span style="font-family: monospace;"> + </span><span style="font-family: monospace;"><a href="#dI">I</a> + +diag + - lines used to improve fit<br> + </span></small><small><span style="font-family: monospace;"> + </span><a style="font-family: monospace;" href="#dc">c</a><span + style="font-family: monospace;"> +diag + - lines perspective corrected</span></small><br + style="font-family: monospace;"> + <small><span style="font-family: monospace;"></span><span + style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#dr">r</a><span + style="font-family: monospace;"> +diag + - lines rotated</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#ds">s</a><span + style="font-family: monospace;"> +diag + - sample boxes rotated</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#do">o</a><span + style="font-family: monospace;"> +diag + - sample box outlines</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#dn">n</a><span + style="font-family: monospace;"> +diag + - sample box names</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#da">a</a><span + style="font-family: monospace;"> +diag + - sample box areas</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#dp">p</a><span + style="font-family: monospace;"> +diag + - pixel areas sampled</span></small> + <br> + <small><span style="font-family: monospace;"> + <a href="#O">-O</a> + outputfile + Override the default output filename + & extension.</span></small><br> + <h3>Usage Details and Discussion</h3> + <span style="font-weight: bold;">scanin</span> is setup to deal with + a + raster file that has been roughly cropped to a size that contains + the + test chart. It's exact orientation is not important [ie. there is + usually no need to rotate or crop the image any more finely.] The + reference files are normally set up with the assumption that the + edges + of the chart are visible within the image, and if the image is + cropped + to exclude the chart edges, it may well not recognize the chart + properly. It is designed to cope with a variety of resolutions, and + will cope with some degree of noise in the scan (due to screening + artefacts on the original, or film grain), but it isn't really + designed + to accept very high resolution input. For anything over 600DPI, you + should consider down sampling the scan using a filtering downsample, + before submitting the file to scanin. Similarly, any file with a + large + level of noise (due to screening or scanner artefacts) should + consider + down sampling the image or filtering it with some average preserving + filter before submitting it to scanin. Examining the diagnostic + output + (ie. -dig and -dil) may help in determining whether noise is an + issue.<br> + <br> + There are 5 basic modes that <b>scanin</b> operates in.<br> + <ul> + <li><a name="_"></a>When no special argument is given scanin is + assumed to be parsing an input device characterization chart + (ie. an + IT8.7/2 chart), for the purpose of creating a <a + href="File_Formats.html#.ti3">.ti3</a> data file containing + the CIE test values and the corresponding RGB scanner values. + The <a href="File_Formats.html#.ti3">.ti3</a> file can then be + used for + creating + an input profile using <a href="colprof.html">colprof</a>. The + file + arguments are: <a name="_p1"></a>The TIFF file that is to be + processed, <a name="_p2"></a>the image recognition template + file, <a name="_p3"></a>the CIE reference value definitions for + the test chart + (sometimes labeled a ".q60" file), <a name="_p4"></a>and an + optional + name for the image recognition + diagnostic output. The resulting .ti3 file will have the same + base name + as the input TIFF file.</li> + <li><a name="g"></a>If the<b> -g</b> flag is specified, then + scanin + is operating in a mode designed to create the necessary image + recognition template file (<a href="File_Formats.html#.cht">.cht</a>) + boilerplate information. Patch + location and labeling information would need to be added + manually to + such + a generated file, to make a complete and useable recognition + template + file. <a href="cht_format.html">CHT file format.</a> The input + TIFF + file in + this situation, should be a good quality image, perhaps + synthetically + generated + (rather than being scanned), and perfectly oriented, to make + specification + of the patch locations easier. The file arguments are: <a + name="gp1"></a>The + TIFF file that + is to be processed, <a name="gp2"></a>the image recognition + template + file to be created, <a name="gp3"></a>and + an optional name for the image recognition diagnostic output.</li> + <li><a name="o"></a>If the <b>-o</b> flag is used, then scanin + will + process the input TIFF file and produce a generic <a + href="File_Formats.html#CGATS">CGATS</a> + style file containing just the patch values (a <span + style="font-weight: bold;">.val</span> file). The file + arguments + are: <a name="op1"></a>The TIFF file that is to be processed, <a + name="op2"></a>the image recognition template file + to be created, <a name="op3"></a>and an optional name for the + image + recognition diagnostic + output.</li> + <li><a name="c"></a>If the <b>-c</b> flag is used, then an input + image + of a print test chart can be used + in combination with a device profile, to estimate the CIE + tristimulus + values of the patches. This allows RGB + input devices to be used as a crude replacement for a color + measuring + instrument. The icc or mpp profile has + (presumably) been + created by scanning an IT8.7/2 chart (or similar) through the + RGB input + device, + and + then using scanin to create the .ti3 file needed to feed to + colprof to + create + the input device profile. The file arguments in -c mode are: <a + name="cp1"></a>The + TIFF file that + is to be processed containing the image of a print test chart, <a + name="cp2"></a>the image recognition template file for the + test chart + generated by the <a href="printtarg.html"> printtarg</a> tool, + <a name="cp3"></a>the input device ICC or MPP profile, <a + name="cp4"></a>the + base + name for the .ti2 file containing the + test chart printer device + values and their patch identifiers and the base name for the + resulting + .ti3 + file, <a name="cp5"></a>and finally an optional name for the + image + recognition diagnostic output. + The resulting .ti3 file will have the same base name as the + input TIFF + file. + If there is more than one page in the test chart, then scanin + will need + to be run multiple times, once for each scan file made from each + test + chart. <a name="ca"></a>The <b>-ca</b> flag combination should + be + used + for all pages after the first, + as this then adds that pages test values to the .ti3 file, + rather than + creating + a .ti3 file that contains only that pages test values. If the + incoming + .ti2 file contains per-channel calibration + curves, these will be passed through to the .ti3 so that + accurate ink + limits can be computed during profiling. </li> + <li><a name="r"></a>If the <span style="font-weight: bold;">-r</span> + flag is used, then the input TIFF value + is used as a source of device values to replace any existing + device + values in the given .ti3 + file. This is intended for use in the situation in which the + device + values + being fed into an output device are altered in some way that is + difficult + to predict (ie. such as being screened and then de-screened), + and this + alteration + to the device values needs to be taken into account in creating + a + profile + for such a device. The file arguments in -r mode are: <a + name="rp1"></a>The + TIFF file that + is to be processed containing a rasterized image of an output + test + chart, <a name="rp2"></a>the image recognition template file + for the + test + chart generated by the <a href="printtarg.html"> printtarg</a> + tool, <a name="rp3"></a>the base name for + the .ti2 file containing the output test chart device values and + their + patch + identifiers and the base name for the .ti3 file that is to have + its + device + values replaced, <a name="rp4"></a>and finally an optional name + for + the + image recognition diagnostic + output.<br> + </li> + </ul> + A number of flags and options are available, that are independent of + the + mode that scanin is in.<br> + <br> + Normally scanin will try and recognize a chart, irrespective of its + orientation. For charts that have some asymmetric patch size or + arrangement (such as an IT8.7/2, or a chart generated by <a + href="printtarg.html"> printtarg</a> + with the <b>-s</b> option), this is both flexible and reliable. + Other + charts + may be symmetrical, and therefore having scanin figure out the + orientation + automatically is a problem if the recognition template does not + contain + expected patch values, since it will have an equal chance of + orienting + it incorrectly as correctly. To solve this, the <a name="a"></a><b>-a</b> + flag can be + used, + and care taken to provide a raster file that is within 45 degrees of + "no + rotation".<br> + <br> + <a name="F"></a>Normally scanin will use automatic chart recognition + to + identify the location of the test patches and extract their values. + If + the chart <a href="cht_format.html">CHT file</a> + has four fiducial marks defined, then the chart can be manually + aligned by specifying the pixel location of the four marks as + arguments to the <span style="font-weight: bold;"><span + style="font-weight: bold;">-F</span></span> flag. The top left, + top + right, bottom right and bottom left fiducial marks X and Y + co-ordinates + should be + specified as a single concatenated argument, separated by comma's, + e.g: + -F 10,20,435,22,432,239,10,239 The coodinates may be + fractional using a decimal point. + Four fiducial marks allows for compensation for perspective + distortion.<br> + <br> + <a name="p"></a>By default the automatic chart recognition copes + with + rotation, scale and stretch in the chart image, making it suitable + for + charts that have been scanned, or shot squarely with a camera. If a + chart has been shot not exactly facing the camera (perhaps to avoid + reflection, or to get more even lighting), then it will suffer from + perspective distortion as well. The <span style="font-weight: + bold;"><span style="font-weight: bold;">-p</span></span> flag + enables automatic + compensation for perspective distortion.<br> + <br> + <a name="m"></a>Normally scanin computes an average of the pixel + values + within a sample square, using a "robust" mean, that discards pixel + values that are too far from the average ("outlier" pixel values). + This + is done in an attempt to discard value that are due to scanning + artefacts such as dust, scratches etc. You can force scanin to + return + the true mean values for the sample squares that includes all the + pixel + values, by using the <span style="font-weight: bold;">-m</span> + flag.<br> + <br> + <a name="G"></a>Normally scanin has reasonably robust feature + recognition, but the default assumption is that the input chart has + an + approximately even visual distribution of patch values, and has been + scanned and converted to a typical gamma 2.2 corrected image, + meaning + that the average patch pixel value is expected to be about 50%. If + this + is not the case (for instance if the input chart has been scanned + with + linear light or "raw" encoding), then it may enhance the image + recognition to provide the approximate gamma encoding of the image. + For + instance, if linear light encoding ("Raw") is used, a <span + style="font-weight: bold;">-G</span> value of 1.0 would be + appropriate. Values less than 2.2 should be tried if the chart is + particularly dark, or greater than 2.2 if the chart is particularly + light. Generally it is only necessary to provide this is there are + problems in recognizing the chart.<br> + <br> + <a name="v"></a> The <b>-v</b> flag enables extra verbosity in + processing. This can aid debugging, if a chart fails to be + recognized.<br> + <br> + <a name="d"></a> The <b>-d</b> flag enables the generation of an + image + recognition diagnostic raster. The name of diagnostic raster can be + specified as the last in the + command line, or if not, will default to <span style="font-weight: + bold;">diag.tif</span>. Various flags control what + is written to the diagnostic + raster. + Note that at least one flag must be specified for a diagnostic + raster + to be produced.<br> + <b><a name="di"></a>i</b> creates a black and + white + version of the input raster in the diagnostic output, to be able to + compare with the feature extraction.<br> + <b><a name="dh"></a>h</b> will show pixels in the + input image classified as being on horizontal edges, in red.<br> + <b><a name="dv"></a>v</b> will show pixels in the + input image classified as being vertical edges, in green.<br> + <b><a name="dg"></a>g</b> will show groups of + pixels + that will be used + to estimate edge lines, each group in a different color.<br> + <b><a name="dl"></a>l</b> will show valid lines + estimated from the vertical and horizontal pixel groups, in white.<br> + <b><a name="dL"></a>L</b> will show all lines + (valid + and invalid) estimated from the vertical and horizontal pixel + groups, + in white.<br> + <b><a name="dI"></a>I</b> will show valid lines lines + used + to improve the final fit, + in blue.<br> + <b><a name="dc"></a>c</b> will show the lines with + perspective correction applied in cyan.<br> + <b><a name="dr"></a>r</b> will show the lines + rotated + to the reference + chart orientation, in yellow.<br> + <b><a name="ds"></a>s</b> will show the diagnostic + sampling box edge outlines, rotated to the reference chart + orientation, + in orange.<br> + <b><a name="do"></a>o</b> will show all the + sampling + box edge outlines, in orange.<br> + <b><a name="dn"></a>n</b> will show the ID names + of + the sampling boxes, plus the diagnostic sample boxes, using a simple + stroke font, in orange.<br> + <b><a name="da"></a>a</b> will show the sampling + areas as crossed boxes, plus the diagnostic sample boxes, in orange.<br> + <b><a name="dp"></a>p</b> will show the sampling + areas as colored pixels.<br> + <br> + The combination of <b>-dipn</b> is usually a good place to start.<br> + <br> + The <a href="File_Formats.html#TIFF">TIFF</a> file can be either 8 + or + 16 bits per color component, with 16 bit files being slower to + process, + but yielding more precise results.<br> + <br> + If at all in doubt that the file has been recognized correctly, use + the + <span style="font-weight: bold;">-dipn</span> diagnostic flag + combination, and check the resulting diagnostic raster file.<br> + [ A badly recognised image will typically result in high self fit + delta E's when used with colprof. ]<br> + <br> + <a name="O"></a>The <span style="font-weight: bold;">-O</span> + parameter allows the + output file name & extension to be specified independently of + the + last tiff + filename. Note that the full filename must be specified, including + the + extension.<br> + <br> + <br> + <br> + </body> +</html> |