What is the difference between a PES packet and a PSI section?
A PES packet is a way to uniformly packetize elementary streams. Embedded in PES packets, elementary streams may be synchronized with time stamps. They are not protected. The PES packets may be of variable length, which allows them to be also of fixed length. PES packets may be rather long packets. As elementary streams are continuous streams, it is also possible to know that a PES packet is finished because the next PES packet arrives. Therefore, sometimes a length indication is not even relevant (for video PES packets). A PSI section is a way to carry a portion of a PSI table. A PSI section is a way to uniformly represent signalling. PSI sections are not synchronized. They may be protected by a CRC. The sections are of a variable length. They are rather small. The length is always relevant. It is the only mechanism to go from one section to the next section when they are carried in the same packet. An update mechanism is also supported which allows association of a version number to
PES A PES packet is a way to uniformly packetize elementary streams. Embedded in PES packets, elementary streams may be synchronized with time stamps. They are not protected. The PES packets may be of variable length, which allows them to be also of fixed length. PES packets may be rather long packets. But as elementary streams are continuous streams, it is also possible to know when a PES packet is finished when the next PES packet arrives. Sometimes the length is not even relevant (for video PES packets). PSI sections A PSI section is a way to carry a portion of a PSI table. A PSI section is a way to uniformly represent signaling. PSI sections are not synchronized. They may be protected by a CRC. The sections are of a variable length. They are rather small. The length is always relevant. It is the only mechanism to go from one section to the next section when they are carried in the same packet. An update mechanism is also supported which allowsassociation of a version number to a se
