🌅 Trim option for PDFs images (#688)

jupyter-book · Oct 20, 2023 · 5ede905 · 5ede905
1 parent 207b2f0
commit 5ede905
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Showing 3 changed files with 19 additions and 5 deletions.
diff --git a/.changeset/fifty-owls-raise.md b/.changeset/fifty-owls-raise.md
@@ -0,0 +1,5 @@
+---
+'myst-cli': patch
+---
+
+Trim PDFs when converting to PNG, ensure WEBP conversion does not overwrite
diff --git a/packages/myst-cli/src/transforms/images.ts b/packages/myst-cli/src/transforms/images.ts
@@ -243,11 +243,15 @@ type ConversionFn = (
 /**
  * Factory function for all simple imagemagick conversions
  */
-function imagemagickConvert(to: ImageExtensions, from: ImageExtensions) {
+function imagemagickConvert(
+  to: ImageExtensions,
+  from: ImageExtensions,
+  options?: { trim?: boolean },
+) {
   return async (session: ISession, source: string, writeFolder: string, opts: ConversionOpts) => {
     const { imagemagickAvailable } = opts;
     if (imagemagickAvailable) {
-      return imagemagick.convert(to, from, session, source, writeFolder);
+      return imagemagick.convert(to, from, session, source, writeFolder, options);
     }
     return null;
   };
@@ -329,7 +333,9 @@ const conversionFnLookup: Record<string, Record<string, ConversionFn>> = {
     [ImageExtensions.png]: svgToPng,
   },
   [ImageExtensions.pdf]: {
-    [ImageExtensions.png]: imagemagickConvert(ImageExtensions.pdf, ImageExtensions.png),
+    [ImageExtensions.png]: imagemagickConvert(ImageExtensions.pdf, ImageExtensions.png, {
+      trim: true,
+    }),
   },
   [ImageExtensions.gif]: {
     [ImageExtensions.png]: gifToPng,

diff --git a/packages/myst-cli/src/utils/imagemagick.ts b/packages/myst-cli/src/utils/imagemagick.ts
@@ -79,6 +79,7 @@ export async function convert(
   session: ISession,
   input: string,
   writeFolder: string,
+  options?: { trim?: boolean },
 ) {
   if (!fs.existsSync(input)) return null;
   const { name, ext } = path.parse(input);
@@ -91,7 +92,9 @@ export async function convert(
     session.log.debug(`Cached file found for converted ${inputFormatUpper}: ${input}`);
     return filename;
   } else {
-    const executable = `convert -density 600 -colorspace RGB ${input} ${output}`;
+    const executable = `convert -density 600 -colorspace RGB ${input}${
+      options?.trim ? ' -trim' : ''
+    } ${output}`;
     session.log.debug(`Executing: ${executable}`);
     const exec = makeExecutable(executable, createImagemagikLogger(session));
     try {
@@ -181,7 +184,7 @@ export async function convertImageToWebp(
   const convertGif = makeExecutable(`gif2webp -q ${quality} "${image}" -o "${webp}"`, debugLogger);
   // Density has to be BEFORE the PDF
   const convertPdfPng = makeExecutable(
-    `convert -density 600 -colorspace RGB ${image} ${png}`,
+    `convert -density 600 -colorspace RGB ${image} -trim ${png}`,
     debugLogger,
   );
   const convertPdfWebP = makeExecutable(`cwebp -q ${quality} "${png}" -o "${webp}"`, debugLogger);