PDF-kompressor vs Bildkompressor: Vilken Behöver Du?
Quick Answer
Använd PDF Compressor för .pdf-filer (rapporter, dokument). Använd Image Compressor för bildfiler (.jpg, .png, .webp). Om din PDF är stor på grund av inbäddade bilder, komprimera bilderna först —eller använd PDF Compressor som hanterar båda.
Introduction
PDF Compressor och Image Compressor reducerar båda filstorlek, men de targetar olika filtyper och använder olika tekniker. PDF-komprimering fungerar på multi-page-dokument innehållande text, bilder och vektorer. Bildkomprimering fungerar på single-image-filer (JPEG, PNG, WebP). Vilken du använder beror på filtyp och vad som finns inuti.
Step by Step
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Compare what they compress
PDF Compressor: reduces PDF file size by optimizing embedded images, compressing text streams, removing duplicate objects, and stripping metadata. Image Compressor: reduces image file size by adjusting quality (JPEG), optimizing palette (PNG), or converting format (WebP).
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Compare techniques
PDF: recompress embedded images (JPEG quality reduction), deduplicate shared objects, compress content streams (FlateDecode), remove unused resources, subset fonts. Image: quantization (reduce color depth), DCT compression (JPEG), dictionary compression (PNG), transform coding (WebP).
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Compare quality trade-offs
PDF: text remains crisp (vector), images inside may lose quality. Overall document readability is preserved. Image: direct quality loss — JPEG introduces artifacts, PNG loses color precision, WebP balances quality and size. Image compression is more visible because the entire output is a raster image.
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Compare use cases
PDF Compressor: large reports, scanned documents, ebooks, print-ready files, email attachments. Image Compressor: web images, photos for upload, social media, thumbnails, CDN assets. If your PDF contains mostly images (scanned doc), both tools can help — compress images before embedding.
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Decide based on your file
File is .pdf: PDF Compressor. File is .jpg/.png/.webp: Image Compressor. PDF is large due to images: extract images, compress with Image Compressor, rebuild PDF. Need to reduce email attachment: compress the file type you have. Need web optimization: Image Compressor for assets, PDF Compressor for downloadable docs.
Examples
Same content as PDF vs Image
Input: A 10-page report with charts:
- As PDF: 5 MB → PDF Compressor → 1.5 MB (70% reduction)
- As PNG screenshot: 3 MB → Image Compressor → 500 KB (83% reduction)
Output: Image compression achieves higher ratio for raster content. PDF preserves text quality and multi-page structure.
Common Problems
- Scanned PDFs are images: a scanned PDF stores each page as a raster image, so PDF Compressor applies image compression internally — compress the source images at high quality before scanning for best results.
- JPEG artifacts in PDFs: aggressively compressing embedded JPEGs in a PDF introduces visible blockiness — use quality 75-85 for photos and keep text as vector for crispness.
- PNG has no lossy mode: PNG is lossless, so Image Compressor can only optimize palette and metadata — convert to WebP or JPEG if you need aggressive size reduction for photos.
- PDF text reflow: PDF compression does not reflow text, so removing metadata or compressing streams reduces size without changing layout — but OCR on scanned PDFs may shift text positions.
Tips
- Compress images before embedding them in a PDF — this gives you per-image quality control and better results than compressing the final PDF alone.
- Use PDF Compressor for multi-page documents where text quality matters, and Image Compressor for single images where aggressive quality reduction is acceptable.
- For web optimization, convert images to WebP format (smaller than JPEG/PNG) and use PDF Compressor only for downloadable documents.
- If your PDF is large because of embedded images, extract the images, compress them with Image Compressor, then rebuild the PDF — this two-step approach gives the best size reduction.