commit 1287c88af48059edaba05afaf956122c2c54052d
parent 40ff17e96ed3d5370d7d7a1d4faf6a9f37b96af9
Author: Martin Kloeckner <mjkloeckner@gmail.com>
Date: Tue, 19 Nov 2024 13:35:41 -0300
new post: `imagemagick-use-case-export-and-process-ltspice-schematics`
Diffstat:
7 files changed, 172 insertions(+), 4 deletions(-)
diff --git a/blog/imagemagick-use-case-export-and-process-ltspice-schematics/copy_to_clipboard_cropped.png b/blog/imagemagick-use-case-export-and-process-ltspice-schematics/copy_to_clipboard_cropped.png
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diff --git a/blog/imagemagick-use-case-export-and-process-ltspice-schematics/copy_to_clipboard_cropped2.png b/blog/imagemagick-use-case-export-and-process-ltspice-schematics/copy_to_clipboard_cropped2.png
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diff --git a/blog/imagemagick-use-case-export-and-process-ltspice-schematics/imagemagick-use-case-export-and-process-ltspice-schematics.md b/blog/imagemagick-use-case-export-and-process-ltspice-schematics/imagemagick-use-case-export-and-process-ltspice-schematics.md
@@ -0,0 +1,164 @@
+%%
+title: "ImageMagick use case: export and process LTSpice schematic images"
+date: "19-Nov-2024"
+%%
+
+# ImageMagick use case: export and process LTSpice schematic images
+
+In this post I explain how I managed to simplify to a 'one-liner' the series of
+steps involved in exporting and processing the image of an LTSpice schematic for
+further use in a report paper or any similar document.
+
+> ***TL;DR***
+>
+> Copy to clipboard the current view of the schematic in LTSpice: `right click >
+> view > copy image to clipboard`, then, using xclip, pipe the content of the
+> clipboard to magick and save the image with name `schematic.png`, in black and
+> white (`-colorspace grey`) and cropped to the contents of the image (`-trim`)
+>
+> ```console
+> xclip -selection clipboard -t image/bmp -o | magick - -colorspace grey -trim schematic.png
+> ```
+> <!--`-->
+
+## Getting an image of the schematic from LTSpice
+
+First we copy the current schematic view in LTSpice to the clipboard with:
+`right click on an empty space of the schematic > view > copy image to
+clipboard`.
+
+
+
+Others may just take a screenshot of the schematic, this is also a valid way of
+getting an image of the schematic but as we'll see later it's more practical to
+just copy the image to clipboard since it doesn't require the creation of a new
+temporary file.
+
+## Previous Procedure
+
+<!--
+First we copy the current schematic view of LTSpice to clipboard with: `right
+click on an empty space of the schematic > view > copy image to clipboard`.
+
+
+
+Other may just take a screenshot of the schematic, this is also a valid way of
+getting an image of the schematic but in my experience it's better, and simpler,
+to copy the image to clipboard
+-->
+
+After copying the image to the clipboard from LTSpice as seen in the previous
+section, just using a GUI program like gimp, paste the image from the clipboard,
+crop the image, apply black and white filters, etc; finally export the image.
+
+This procedure looks simple, but when doing it with multiple schematics it turns
+tedious. In the current procedure the steps after copying the image shrinks to a
+one-liner (a single line containing one or more chained commands).
+
+## Current Procedure
+
+<!--
+Copying the schematic image from LTSpice is the same as the previous way, the
+steps that change are the following ones which involve getting the image from
+the clipboard, processing it and finally exporting it to a file. In this new
+procedure we use a series of chained command line commands to obtain that.
+-->
+
+Instead of using a GUI program after copying the image to the clipboard from
+LTSpice, we use a series of command line tools to process and save the image, in
+particular, xclip to manage the clipboard contents (X session) and ImageMagick
+to process the image.
+
+### Getting the image from the clipboard
+
+To get the image from the clipboard we use xclip (xclip works for an X session,
+if you are using Wayland you may use [wl-clipboard](https://github.com/bugaevc/wl-clipboard)
+which it may have similar commands to the ones seen on this post).
+
+<!--
+Then we can query the format of the copied image by specifying the `TARGETS`
+target to xclip, as follows:
+
+After copying the image from LTSpice, you may query the supoorted image formats
+of that image, you can do that
+-->
+
+After copying the image from LTSpice, you may query the supported image formats
+of the clipboards contents, you can do that by providing the `TARGETS` to the
+target flag `-t` as show next.
+
+```console
+$ xclip -selection clipboard -t TARGETS -o
+PIXMAP
+image/bmp
+TARGETS
+MULTIPLE
+TIMESTAMP
+```
+
+Notice that we provide the `-selection clipboard` flag, this selects the
+clipboard named `clipboard` (there is also `primary` and `secondary`). In this
+case we use LTSpice running on wine so it may use a different clipboard for
+other installations.
+
+Specifying the `image/bmp` target to xclip and no filename to the output flag
+`-o`, will result in xclip printing the binary data to standard output (this
+will probably mess the terminal). By piping the binary data to a file, as shown
+next, we can make sure if the data is a bitmap formatted image.
+
+```console
+$ xclip -selection clipboard -t image/bmp -o > schematic_raw
+```
+
+Executing the `file` command on the new file `schematic_raw` reveals that
+effectively it is a bitmap file.
+
+```console
+$ file schematic_raw
+schematic_raw: PC bitmap, Windows 3.x format, 1916 x 966 x 32, 3 compression,
+image size 7403424, cbSize 7403490, bits offset 66
+```
+
+The raw schematic image, in bitmap format, looks exactly as shown in the LTSpice
+schematic view.
+
+
+
+The next step is to convert it to black and white, trim the white margins and
+finally convert it to png format.
+
+### Processing the image using ImageMagick
+
+Instead of piping the output of the xclip command to a file, we pipe the binary
+data to ImageMagick appending a single dash `-` to tell magick to read from
+standard input. To apply the desired effects on the image we also append the
+flag `-colorspace grey`, to make the image black and white, the flag `-trim`,
+to crop the image to the content, and finally we save the resulting image in png
+format by appending the extension to the output file name (for example
+`schematic.png`).
+
+```console
+$ xclip -selection clipboard -t image/bmp -o | magick - -colorspace grey -trim schematic.png
+```
+
+The final image results as follows
+
+
+
+ImageMagick can also read from a file, for example if you took a screenshot of
+the schematic, you can process it by specifying the input file name, instead of
+reading from standard input.
+
+```console
+$ magick schematic_screenshot.png -colorspace grey -trim schematic.png
+```
+
+<!--
+Simply pipe the output of the clipboard to ImageMagick and add the flag
+`-colorspace grey`, to make the image black and white, and the flag `-trim` to
+crop the image to the content.
+
+output of the magick command is the following image, which is in black and
+white plus the margins are cropped, resulting in an image ready for inserting in
+a paper.
+-->
diff --git a/blog/imagemagick-use-case-export-and-process-ltspice-schematics/schematic.png b/blog/imagemagick-use-case-export-and-process-ltspice-schematics/schematic.png
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diff --git a/blog/imagemagick-use-case-export-and-process-ltspice-schematics/schematic_raw.png b/blog/imagemagick-use-case-export-and-process-ltspice-schematics/schematic_raw.png
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diff --git a/common/blog_index.shtml b/common/blog_index.shtml
@@ -2,6 +2,10 @@
<thead id="blog-index-thead">
</thead>
<tbody id="blog-index-tbody">
+ <tr id="entry" onclick="window.location='/blog/imagemagick-use-case-export-and-process-ltspice-schematics/imagemagick-use-case-export-and-process-ltspice-schematics.html';">
+ <td id="date"><a href="/blog/imagemagick-use-case-export-and-process-ltspice-schematics/imagemagick-use-case-export-and-process-ltspice-schematics.html">19-Nov-2024</a></td>
+ <td id="title"><a href="/blog/imagemagick-use-case-export-and-process-ltspice-schematics/imagemagick-use-case-export-and-process-ltspice-schematics.html">ImageMagick use case: export and process LTSpice schematic images</a></td>
+ </tr>
<tr id="entry" onclick="window.location='/blog/grub-linux-version-fix/grub-linux-version-fix.html';">
<td id="date"><a href="/blog/grub-linux-version-fix/grub-linux-version-fix.html">02-Nov-2024</a></td>
<td id="title"><a href="/blog/grub-linux-version-fix/grub-linux-version-fix.html">GRUB menu: Linux version not detected</a></td>
diff --git a/common/latest_uploads.shtml b/common/latest_uploads.shtml
@@ -2,6 +2,10 @@
<thead id="blog-index-thead">
</thead>
<tbody id="blog-index-tbody">
+ <tr id="entry" onclick="window.location='/blog/imagemagick-use-case-export-and-process-ltspice-schematics/imagemagick-use-case-export-and-process-ltspice-schematics.html';">
+ <td id="date"><a href="/blog/imagemagick-use-case-export-and-process-ltspice-schematics/imagemagick-use-case-export-and-process-ltspice-schematics.html">19-Nov-2024</a></td>
+ <td id="title"><a href="/blog/imagemagick-use-case-export-and-process-ltspice-schematics/imagemagick-use-case-export-and-process-ltspice-schematics.html">ImageMagick use case: export and process LTSpice schematic images</a></td>
+ </tr>
<tr id="entry" onclick="window.location='/blog/grub-linux-version-fix/grub-linux-version-fix.html';">
<td id="date"><a href="/blog/grub-linux-version-fix/grub-linux-version-fix.html">02-Nov-2024</a></td>
<td id="title"><a href="/blog/grub-linux-version-fix/grub-linux-version-fix.html">GRUB menu: Linux version not detected</a></td>
@@ -22,9 +26,5 @@
<td id="date"><a href="/blog/nerdearla-2022/nerdearla-2022.html">23-Sep-2022</a></td>
<td id="title"><a href="/blog/nerdearla-2022/nerdearla-2022.html">I'm going to Nerdearla 2022</a></td>
</tr>
- <tr id="entry" onclick="window.location='/blog/sav/sav.html';">
- <td id="date"><a href="/blog/sav/sav.html">18-Sep-2022</a></td>
- <td id="title"><a href="/blog/sav/sav.html">Sorting Algorithms Visualized</a></td>
- </tr>
</tbody>
</table>
