The information in this site is the result of my researches in the Internet and of my experiences. This information below is solely used for my purpose and may not be suitable for others.
1. Reading the block size and the volume size:
# isoinfo -d -i /dev/sr0 | grep -i -E 'block size|volume size'
Logical block size is: 2048
Volume size is: 327867
2. Running dd with the parameters for block size and volume size:
# dd if=/dev/sr0 of=/tmp/test.iso bs=