draw 'roundrectangle 16, 5, 180, 85 20,40' -tile gradient:chartreuse1-chartreuse3 \ draw 'roundrectangle 264, 5, 304, 85 20,40' -tile gradient:chartreuse-green \ Given the complexity of the rendering, you might be surprised it is accomplished by a single command-line: magick -size 320x90 canvas:none -stroke snow4 -size 1x90 -tile gradient:white-snow4 \ Here we show percent completion of a task as a shaded cylinder: However, very few may realize the second, more complex command, gives a flat two-dimensional label a three-dimensional look with rich textures and simulated depth: Without knowing much about the ImageMagick command-line, you can probably surmise that the first command above converts an image in the JPEG format to one in the PNG format. There are some other differences between Windows and Linux (involving quotation marks, for instance), but we'll discuss some of those issues later, as they arise.įor most command line examples on this site, if there is an equivalent translation to run on windows there will be a dropdown in the bottom right, letting you switch which operating system you are previewing the command for. The parentheses that are escaped above using the backslash are not escaped in Windows. Line continuation characters need not be entered. Sometimes, however, the lines are wrapped by your browser if the browser window is small enough, but the command-lines, shown in white, are still intended to be typed as one line. We use the Linux style on these web pages, as above. In the Windows shell, use a carat character ( ^) for line-continuation. The backslash is the Linux line-continuation character. This example command is long enough that the command must be written across several lines, so we formatted it for clarity by inserting backslashes ( \). delete 0 +swap -compose Multiply -composite button.gif \( -clone 0 -shade 110x50 -normalize -channel BG -fx 0 +channel -alpha Off \) \ \( +clone -shade 110x90 -normalize -negate +clone -compose Plus -composite \) \ Or it can be complex with a plethora of options, as in the following: magick label.gif -alpha Set \ You can't get higher quality than that.The ImageMagick command-line tools can be as simple as this: magick image.jpg image.png The extracted JPEGs were byte-for-byte identical to I tried this command on a PDF that I had made myself from a sequence (depending on what bitmap format the PDF was using). You may or may not need to follow that with a convert to. By default, pdfimages convertsĮverything to PNM format, and converting JPEG > PPM > JPEG is a lossy ![]() Probably also want to use the -j option to pdfimages, because a Them, because it gets you the raw data at its original size. Series of bitmaps, pdfimages will do a much better job of extracting It simply ignores any text or vectorĪs a result, if what you have is a PDF that's just a wrapper around a Pdfimages looks through the PDF for embedded bitmap images andĮxports each one to a file. pdfimagesĭoes not do the same thing that convert does when given a PDF asĬonvert takes the PDF, renders it at some resolution, and uses the Update: As you pointed out, gscan2pdf (the way you're using it) is just a wrapper for pdfimages (from poppler). (You can prepend -units PixelsPerInch or -units ![]() Perhaps you need to use -density to do the conversion at a higherĭpi: convert -density 300 file.pdf page_%04d.jpg Versions (as a PNG to avoid further quality loss). Perhaps cut the same section out of the poor quality and good quality Could you post some samples to illustrate? It's not clear what you mean by "quality loss". TLDR - Use pdfimages : pdfimages -j input.pdf output The method in the answer given here results in an output which is comparable in size to the input and doesn't suffer from quality loss. The currently accepted answer does the job but results in an output which is larger in size and suffers from quality loss. For example: pdftoppm input.pdf outputname -png -rx 300 -ry 300 Converting a single page or a range of pages of the PDF pdftoppm input.pdf outputname -png -f. ![]() This will output each page in the PDF using the format outputname-01.png, with 01 being the index of the page. ![]() You can use pdftoppm from the poppler-utils package to convert a PDF to a PNG: pdftoppm input.pdf outputname -png
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