How can I migrate product images to Magento2?

All media files (images for products, categories, the WYSIWYG editor, and so on) should be copied manually from your Magento 1 install media folder to your Magento 2 install pub/media folder.

However, do not copy the .htaccess files located in the Magento 1 media folder. Magento 2 has its own .htaccess that should be preserved.

Reference: http://devdocs.magento.com/guides/v2.0/migration/migration-manually.html