convert -interlace Plane a.png a.png

convert *.jpg result.pdf

可能存在的错误信息：

1. attempt to perform an operation not allowed by the security policy `PDF'

解决办法：

sudo vim /etc/ImageMagick-6/policy.xml
# 将<policy domain="coder" rights="none" pattern="PDF" />改为<policy domain="coder" rights="read | write" pattern="PDF" />

2. cache resources exhausted

解决办法：

sudo vim /etc/ImageMagick-6/policy.xml
# 将<policy domain="resource" name="disk" value="1GiB"/>改为<policy domain="resource" name="disk" value="8GiB"/>