Pictures like JPEG, PNG ,gif all are in raster file format. So it will pixelated when zoom more than its resolution. So these type images in PDF will pixelated.Other wise picture should be in vector file format. Like Adobe illustrator files, Coraldraw Files etc..
And in some case when you add a good quality images in Ms Office word and Excel it may be pixelated when you export. Here i will give solution for this.
After saving a document, spreadsheet, or presentation which contains an image, a loss of image quality such as blur may occur.
This issue occurs because PowerPoint, Excel, and Word perform a basic compression of images on save.
It is not possible to recover pictures that have already been compressed.
For future saves, compression can be disabled on a per-file basis using the following steps:
- Click the Office Button, and then click Save As.
- Click Tools, and then click Compress Pictures.
- Click Options.
- Click to clear the Automatically perform basic compression on savecheck box.
- Click OK.
- In the Compress Pictures dialog box, click Cancel.
Note: Clicking OK on this dialog will not prevent the issue from occurring.
You can also modify the following registry setting to prevent basic compression from occurring by defaultShare