.ad l .nh .TH convert 1 "1 May 1994" "ImageMagick" .SH NAME convert - converts an input file using one image format to an output file with a differing image format. .SH SYNOPSIS .B "convert" [ \fIoptions\fP ... ] \fIinput_file\fP \fIoutput_file\fP .SH DESCRIPTION \fBconvert\fP converts an input file using one image format to an output file with a differing image format. \fBconvert\fP recognizes the following image formats: .TP 6 .B Tag \fBDescription\fP .PP ------------------------------------------------------------------------------- .TP 6 .B AVS AVS X image file. .TP 6 .B BMP Microsoft Windows bitmap image file. .TP 6 .B CMYK Raw cyan, magenta, yellow, and black bytes. .TP 6 .B EPS Adobe Encapsulated PostScript file. .TP 6 .B EPSF Adobe Encapsulated PostScript file. .TP 6 .B EPSI Adobe Encapsulated PostScript Interchange format. .TP 6 .B FAX Group 3. .TP 6 .B FITS Flexible Image Transport System. .TP 6 .B GIF Compuserve Graphics image file. .TP 6 .B GIF87 Compuserve Graphics image file (version 87a). .TP 6 .B GRAY Raw gray bytes. .TP 6 .B HISTOGRAM .TP 6 .B IRIS SGI RGB image file. .TP 6 .B JPEG .TP 6 .B MAP Red, green, and blue colormap bytes followed by the image colormap indexes. .TP 6 .B MATTE Raw matte bytes. .TP 6 .B MIFF Magick image file format. .TP 6 .B MTV .TP 6 .B NULL NULL image. .TP 6 .B PCD Photo CD. .TP 6 .B PCX ZSoft IBM PC Paintbrush file. .TP 6 .B PICT Apple Macintosh QuickDraw/PICT file. .TP 6 .B PNM Portable bitmap. .TP 6 .B PS Adobe PostScript file. .TP 6 .B PS2 Adobe Level II PostScript file. .TP 6 .B RAD Radiance image format. .TP 6 .B RGB Raw red, green, and blue bytes. .TP 6 .B RLE Utah Run length encoded image file; read only. .TP 6 .B SUN SUN Rasterfile. .TP 6 .B TEXT raw text file; read only. .TP 6 .B TGA Truevision Targa image file. .TP 6 .B TIFF Tagged Image File Format. .TP 6 .B VICAR read only. .TP 6 .B VID Visual Image Directory. .TP 6 .B VIFF Khoros Visualization image file. .TP 6 .B X select image from X server screen. .TP 6 .B XC constant image of X server color. Specify the desired color as the filename. .TP 6 .B XBM X11 bitmap file. .TP 6 .B XPM X11 pixmap file. .TP 6 .B XWD X Window System window dump image file. .TP 6 .B YUV CCIR 601 4:1:1 file. .TP 6 .B YUV3 CCIR-601 4:1:1 files. .PP .SH EXAMPLES .PP To convert a \fIMIFF\fP image of a cockatoo to a SUN raster image, use: .PP .B convert cockatoo.miff sun:cockatoo.ras .PP To convert a multi-page \fIPostscript\fP document to individual FAX pages, use: .PP .B convert -monochrome document.ps fax:page .PP To convert a TIFF image to a \fIPostscript\fP A4 page with the image in the lower left-hand corner, use: .PP .B convert -page 595x842+0+0 image.tiff document.ps .PP To convert a raw \fBGRAY\fP image to a portable graymap, use: .PP .B convert -size 768x512 gray:raw image.pgm .PP To convert a Photo CD image to a TIFF image, use: .PP .B convert -size 1536x1024 img0009.pcd image.tiff convert img0009.pcd[4] image.tiff .PP To create a visual image directory of all your JPEG images, use: .PP .B convert 'vid:*.jpg' directory.miff .PP To identify the dimensions and the type of an image file, use: .PP .B convert -verbose image null: .SH OPTIONS .TP 5 .B "-blur" blur the image. .TP 5 .B "-border \fIxfP" surround the image with a border or color. See \fBX(1)\fP for details about the geometry specification. The color of the border is obtained from the X server and is defined as \fBbordercolor\fP (class \fBborderColor\fP). See \fBX(1)\fP for details. .TP 5 .B "-colors \fIvalue\fP" preferred number of colors in the image. The actual number of colors in the image may be less than your request, but never more. Note, this is a color reduction option. Images with less unique colors than specified with this option will remain unchanged. Refer to \fBquantize(9)\fP for more details. Note, options \fB-dither\fP, \fB-colorspace\fP, and \fB-treedepth\fP affect the color reduction algorithm. .TP 5 .B "-colorspace \fIvalue\fP" the type of colorspace: \fBGRAY\fP, \fBOHTA\fP, \fBRGB\fP, \fBXYZ\fP, \fBYCbCr\fP, \fBYIQ\fP, \fBYPbPr\fP, or \fBYUV\fP. Color reduction, by default, takes place in the RGB color space. Empirical evidence suggests that distances in color spaces such as YUV or YIQ correspond to perceptual color differences more closely than do distances in RGB space. These color spaces may give better results when color reducing an image. Refer to \fBquantize(9)\fP for more details. The \fB-colors\fP or \fB-monochrome\fP option is required for this option to take effect. .TP 5 .B "-comment \fIstring\fP" annotate an image with a comment. By default, each image is commented with its file name. Use this option to assign a specific comment to the image. Optionally you can include the image filename, type, width, height, or scene number by embedding special format characters. Embed \fB%f\fP for filename, \fB%m\fP for magick, \fB%w\fP for width, \fB%h\fP for height, \fB%s\fP for scene number, or \fB\\n\fP for newline. For example, .nf -comment "%m:%f %wx%h" .fi produces an image comment of \fBMIFF:bird.miff 512x480\fP for an image titled \fBbird.miff\fP and whose width is 512 and height is 480. If the first character of \fIstring\fP is \fB@\fP, the image comment is read from a file titled by the remaining characters in the string. .TP 5 .B "-compress \fItype\fP" the type of image compression: \fIQEncoded\fP or \fIRunlengthEncoded\fP. Specify \fB\+compress\fP to store the binary image in an uncompressed format. The default is the compression type of the specified image file. .TP 5 .B "-contrast" enhance or reduce the image contrast. This option enhances the intensity differences between the lighter and darker elements of the image. Use \fB-contrast\fP to enhance the image or \fB+contrast\fP to reduce the image contrast. .TP 5 .B "-crop \fIx{\+-}{\+-}\fP" preferred size and location of the cropped image. See \fBX(1)\fP for details about the geometry specification. Use cropping to crop a particular area of an image. Use \fB-crop 0x0\fP to remove edges that are the background color. .TP 5 .B "-density \fIx vertical and horizontal density of the image. This option specifies an image density for a Postscript page. The default is 72 dots per inch in the horizontal and vertical direction. Use this option to alter the default density. .TP 5 .B "-despeckle" reduce the speckles within an image. .TP 5 .B "-display \fIhost:display[.screen]\fP" specifies the X server to contact; see \fBX(1)\fP. .TP 5 .B "-dither" apply Floyd/Steinberg error diffusion to the image. The basic strategy of dithering is to trade intensity resolution for spatial resolution by averaging the intensities of several neighboring pixels. Images which suffer from severe contouring when reducing colors can be improved with this option. The \fB-colors\fP option is required for dithering to take effect. .TP 5 .B "-edge" detect edges with an image. .TP 5 .B "-enhance" apply a digital filter to enhance a noisy image. .TP 5 .B "-equalize" perform histogram equalization to the image. .TP 5 .B "-flip" create a "mirror image" by reflecting the image scanlines in the vertical direction. .TP 5 .B "-flop" create a "mirror image" by reflecting the image scanlines in the horizontal direction. .TP 5 .B "-font \fIname\fP" This option specifies the font to be used for displaying normal text. The default is \fBfixed\fP. .TP 5 .B "-gamma \fIvalue\fP" level of gamma correction. The same color image displayed on two different workstations may look different due to differences in the display monitor. Use gamma correction to adjust for this color difference. Reasonable values extend from 0.8 to 2.3. You can apply separate gamma values to the red, green, and blue channels of the image with a gamma value list delineated with commas (i.e. 1.7,2.3,1.2). .TP 5 .B "-geometry \fI{%}x{%}{!}" perferred size or location of the image. By default, the width and height are maximum values. That is, the image is expanded or contracted to fit the width and height value while maintaining the aspect ratio of the image. Append an exclamation point to the geometry to force the image size to exactly the size you specify. For example, if you specify \fB640x480!\fP the image width is set to 640 pixels and height to 480. If only one factor is specified, both the width and height assume the value. To specify a percentage width or height instead, append \fB%\fP. The image size is multiplied by the width and height percentages to obtain the final image dimensions. To increase the size of an image, use a value greater than 100 (e.g. 125%). To decrease an image's size, use a percentage less than 100. .TP 5 .B "-interlace \fItype\fP" the type of interlacing scheme: \fBNONE\fP, \fBLINE\fP, or \fBPLANE\fP. This option is used to specify the type of interlacing scheme for raw image formats such as \fBRGB\fP or \fBYUV\fP. \fBNONE\fP means do not interlace (RGBRGBRGBRGBRGBRGB...), \fBLINE\fP uses scanline interlacing (RRR...GGG...BBB...RRR...GGG...BBB...), and \fBPLANE\fP uses plane interlacing (RRRRRR...GGGGGG...BBBBBB...). .B "-label \fIname\fP" assign a label to an image. Use this option to assign a specific label to the image. Optionally you can include the image filename, type, width, height, or scene number in the label by embedding special format characters. Embed \fB%f\fP for filename, \fB%m\fP for magick, \fB%w\fP for width, \fB%h\fP for height, or \fB%s\fP for scene number. For example, .nf -label "%m:%f %wx%h" .fi produces an image label of \fBMIFF:bird.miff 512x480\fP for an image titled \fBbird.miff\fP and whose width is 512 and height is 480. If the first character of \fIstring\fP is \fB@\fP, the image label is read from a file titled by the remaining characters in the string. When converting to Postscript, use this option to specify a header string to print above the image. .TP 5 .B "-map \fIfilename\fP" choose a particular set of colors from this image. By default, color reduction chooses an optimal set of colors that best represent the original image. Alternatively, you can choose a particular set of colors with this option. .TP 5 .B "-matte" store matte channel if the image has one. .TP 5 .B "-modulate \fIvalue\fP" vary the brightness, saturation, and hue of an image. Specify the percent change in brightness, the color saturation, and the color hue separated by commas. For example, to increase the color brightness by 20% and decrease the color saturation by 10% and leave the hue unchanged, use: \fB-modulate 20,-10\fP. .TP 5 .B "-monochrome" transform the image to black and white. .TP 5 .B "-negate" apply color inversion to image. The red, green, and blue intensities of an image are negated. .TP 5 .B "-noise" reduce the noise in an image with a noise peak elimination filter. The principal function of noise peak elimination filter is to smooth the objects within an image without losing edge information and without creating undesired structures. The central idea of the algorithm is to replace a pixel with its next neighbor in value within a 3 x 3 window, if this pixel has been found to be noise. A pixel is defined as noise if and only if this pixel is a maximum or minimum within the 3 x 3 window. .TP 5 .B "-normalize" transform image to span the full range of color values. This is a contrast enhancement technique. .TP 5 .B "-page \fIx{\+-}{\+-}\fP" preferred size and location of the Postscript page. Use this option to specify the dimensions of the Postscript page in picas or a TEXT page in pixels. The default for a Postscript page is to center the image on a letter page 612 by 792 dots per inch. The left and right margins are 18 picas and the top and bottom 94 picas (i.e. 612x792+36+36). Other common sizes are: 540x720 Note 612x1008 Legal 842x1190 A3 595x842 A4 421x595 A5 297x421 A6 709x1002 B4 612x936 U.S. Foolscap 612x936 European Foolscap 396x612 Half Letter 792x1224 11x17 1224x792 Ledger The page geometry is relative to the vertical and horizontal density of the Postscript page. See \fB-density\fP for details. The default page dimensions for a TEXT image is 612x792+36+36. .TP 5 .B "-quality \fIvalue\fP" JPEG quality setting. Quality is 0 (worst) to 100 (best). The default is 85. .TP 5 .B "-roll \fI{\+-}{\+-}\fP" roll an image vertically or horizontally. See \fBX(1)\fP for details about the geometry specification. A negative \fIx offset\fP rolls the image left-to-right. A negative \fIy offset\fP rolls the image top-to-bottom. .TP 5 .B "-rotate \fIdegrees\fP" apply Paeth image rotation to the image. Empty triangles left over from rotating the image are filled with the color defined as \fBbordercolor\fP (class \fBborderColor\fP). See \fBX(1)\fP for details. .TP 5 .B "-sample \fIgeometry\fP" scale image with pixel sampling. .TP 5 .B "-scene \fIvalue\fP" image scene number. .TP 5 .B "-sharpen" sharpen the image. .TP 5 .B "-shear \fIx\fP" shear the image along the X or Y axis by a positive or negative shear angle. Shearing slides one edge of an image along the X or Y axis, creating a parallelogram. An X direction shear slides an edge along the X axis, while a Y direction shear slides an edge along the Y axis. The amount of the shear is controlled by a shear angle. For X direction shears, \fIx degrees\fP is measured relative to the Y axis, and similarly, for Y direction shears \fIy degrees\fP is measured relative to the X axis. Empty triangles left over from shearing the image are filled with the color defined as \fBbordercolor\fP (class \fBborderColor\fP). See \fBX(1)\fP for details. .TP 5 .B "-size \fI{%}x\fP" width and height of the image. Use this option to specify the width and height of raw images whose dimensions are unknown such as \fBGRAY\fP, \fBRGB\fP, or \fBCMYK\fP. In addition to width and height, use \fB-size\fP to tell the number of colors in a \fBMAP\fP image file, (e.g. -size 640x512+256). For Photo CD images, choose from these sizes: 192x128 384x256 768x512 1536x1024 3072x2048 .TP 5 .B "-treedepth \fIvalue\fP" Normally, this integer value is zero or one. A zero or one tells \fBconvert\fP to choose a optimal tree depth for the color reduction algorithm. An optimal depth generally allows the best representation of the source image with the fastest computational speed and the least amount of memory. However, the default depth is inappropriate for some images. To assure the best representation, try values between 2 and 8 for this parameter. Refer to \fBquantize(9)\fP for more details. The \fB-colors\fP option is required for this option to take effect. .TP 5 .B "-undercolor \fIx\fP" control undercolor removal and black generation on CMYK images. This option enables you to perform undercolor removal and black generation on CMYK images-- images to be printed on a four-color printing system. You can control how much cyan, magenta, and yellow to remove from your image and how much black to add to it. The standard undercolor removal is \fB1.0x1.0\fP. You'll frequently get better results, though, if the percentage of black you add to your image is slightly higher than the percentage of C, M, and Y you remove from it. For example you might try \fB0.5x0.7\fP. .TP 5 .B -verbose print detailed information about the image. This information is printed: image scene number; image name; converted image name; image size; the image class (\fIDirectClass\fP or \fIPseudoClass\fP); the total number of unique colors; and the number of seconds to read and convert the image. .PP Options are processed in command line order. Any option you specify on the command line remains in effect until it is explicitly changed by specifying the option again with a different effect. .PP Change '-' to '+' in any option above to reverse its effect. For example, specify +matte to store the image without its matte channel. .PP By default, the image format is determined by its magic number. To specify a particular image format, precede the filename with an image format name and a colon (i.e. ps:image) or specify the image type as the filename suffix (i.e. image.ps). See \fBDESCRIPTION\fP for a list of valid formats. .PP When you specify \fBX\fP as your image type, the filename has special meaning. It specifies an X window by id, name, or \fBroot\fP. If no filename is specified, the window is selected by clicking the mouse in the desired window. .PP Specify \fIinput_file\fP as \fI-\fP for standard input, \fIoutput_file\fP as \fI-\fP for standard output. If \fIinput_file\fP has the extension \fB.Z\fP or \fB.gz\fP, the file is uncompressed with \fBuncompress\fP or \fBgunzip\fP respectively. If \fIoutput_file\fP has the extension \fB.Z\fP or \fB.gz\fP, the file size is compressed using with \fBcompress\fP or \fBgzip\fP respectively. Finally, precede the image file name with \fI|\fP to pipe to or from a system command. .PP Use an optional index enclosed in brackets after a file name to specify a desired subimage of a multi-resolution image format like Photo CD (e.g. img0001.pcd[4]). .PP Single images are written with the filename you specify. However, multi-part images (i.e. a multi-page Postscript document) are written with the filename followed by a period (\fB.\fP) and the scene number. You can change this behavior by embedding a \fBprintf\fP format specification in the file name. For example, .nf image%02d.miff .fi converts files image00.miff, image01.miff, etc. .SH ENVIRONMENT .PP .TP 5 .B display To get the default host, display number, and screen. .SH SEE ALSO .B display(1), animate(1), import(1), montage(1), mogrify(1), segment(1), combine(1), xtp(1) .SH COPYRIGHT Copyright 1994 E. I. du Pont de Nemours and Company .PP Permission to use, copy, modify, distribute, and sell this software and its documentation for any purpose is hereby granted without fee, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the name of E. I. du Pont de Nemours and Company not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. E. I. du Pont de Nemours and Company makes no representations about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty. .PP E. I. du Pont de Nemours and Company disclaims all warranties with regard to this software, including all implied warranties of merchantability and fitness, in no event shall E. I. du Pont de Nemours and Company be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortuous action, arising out of or in connection with the use or performance of this software. .SH AUTHORS John Cristy, E.I. du Pont De Nemours and Company Incorporated