The output PDF is to large when I merge PDF use the copyPages API of pdf-lib.It maybe 15 times than the original files

[Wayne529]

I use copyPages to merge PDFs, but the output is to large.
And I try embedFont, but it not works, it still to large
the code is blow:
export const mergePDF = async ({pdfFiles,outputFile,cb}) =>{ const fontBytes = fs.readFileSync(join(__dirname, '/font/FZJHSXJW.TTF')) const pdfDoc = await PDFDocument.create() // 处理字体库，为了防止输出体积过大 pdfDoc.registerFontkit(fontkit); await pdfDoc.embedFont(fontBytes,{subset: true}) for(let i=0; i< pdfFiles.length;i++){ const pdfPath = pdfFiles[i] const pdfItem = await PDFDocument.load(fs.readFileSync(pdfPath)) for(let j=0;j<pdfItem.getPageCount();j++){ const [PDFPageItem] = await pdfDoc.copyPages(pdfItem,[j]) pdfDoc.addPage(PDFPageItem) } } const pdfBytes = await pdfDoc.save() // For example,pdfBytescan be: // • Written to a file in Node // • Downloaded from the browser // • Rendered in an <iframe> fs.writeFileSync(outputFile,pdfBytes) // 合并后清空源文件 clearPdfFiles(pdfFiles) cb && cb() }

[seanezell]

I am hitting this exact same problem from AWS Lambda. Attempting to read files from an on-premise file share, merge them, and respond with the base64 of the merged PDF. AWS Lambda and AWS API Gateway both have response size limitations.

My test PDF before being split up was around 2MB. It's being split up by page by another process. When I attempt to merge each PDF back it's resulting in an 18MB PDF.

I cannot seem to find anything out there on what I might be able to do to reduce the filesize.

[Wayne529]

I am hitting this exact same problem from AWS Lambda. Attempting to read files from an on-premise file share, merge them, and respond with the base64 of the merged PDF. AWS Lambda and AWS API Gateway both have response size limitations.

My test PDF before being split up was around 2MB. It's being split up by page by another process. When I attempt to merge each PDF back it's resulting in an 18MB PDF.

I cannot seem to find anything out there on what I might be able to do to reduce the filesize.

It can be works to reduce the size。Maybe the code about bycircle is something wrong previously.
`javascript
export async function mergePdfs(pdfsToMerge: string[]) {
// console.log(pdfsToMerge)
const mergedPdf = await PDFDocument.create();
for (const pdfCopyDoc of pdfsToMerge) {
const pdfBytes = fs.readFileSync(pdfCopyDoc);
const pdf = await PDFDocument.load(pdfBytes);
const copiedPages = await mergedPdf.copyPages(pdf, pdf.getPageIndices());
copiedPages.forEach(page => {
mergedPdf.addPage(page);
});
}
const mergedPdfFile = await mergedPdf.save();
clearPdfFiles(pdfsToMerge);
return mergedPdfFile;
}

`