我正在使用https://www.npmjs.com/package/pdf2pic將我的 PDF 轉換為圖像。const PDF2Pic = require('pdf2pic');const pdf2pic = new PDF2Pic({  density: 100, // output pixels per inch  savename: 'untitled', // output file name  savedir: './images', // output file location  format: 'png', // output file format  size: '600x600', // output size in pixels});const file = "/Users/kar1/Downloads/bw.pdf"async function recognizeFile(file) {  pdf2pic.convertBulk(file, -1).then((resolve) => {    console.log('image converter successfully!');    return resolve;  });}recognizeFile(file)錯誤 ：(node:32605) UnhandledPromiseRejectionWarning: Error: Could not execute GraphicsMagick/ImageMagick: gm "identify" "-ping" "-format" "%p" "/Users/kar1/Downloads/bw.pdf" this most likely means the gm/convert binaries can't be found    at ChildProcess.<anonymous> (/Users/kar1/Desktop/github/pdfToPic/node_modules/gm/lib/command.js:232:12)    at ChildProcess.emit (events.js:315:20)    at Process.ChildProcess._handle.onexit (internal/child_process.js:273:12)    at onErrorNT (internal/child_process.js:469:16)    at processTicksAndRejections (internal/process/task_queues.js:84:21)我試過了 ：brew install imagemagick而且這個問題仍然存在。我該如何解決這個問題？