Is OTA HD compressed differently than Sat HD?

[orange-man]

On my HR20-700, my OTA HD recordings seem to take significantly more hard drive space compared to HD recordings from the satellite. Is there a different form of compression or is it just my imagination?

[mikeny]

On my HR20-700, my OTA HD recordings seem to take significantly more hard drive space compared to HD recordings from the satellite. Is there a different form of compression or is it just my imagination?Almost double as compared to mpeg-4 HD from DirecTV. That's why the HR20 has a variable recording capacity of 30-50 HD Hours.

[mjones73]

The OTA ATSC standard uses MPEG2, as noted, the new HD channels from Directv use MPEG4 which allows tighter compression while retaining the same PQ. Not sure if it's quite half yet but it's still better then MPEG2.

[PoitNarf]

Yep, OTA is MPEG2. Hence the increased hard drive usage.

[California King]

I'm just curious, is MPEG4 the best format to use when it comes to PQ and size? How does XVID or DIVX compare?

[Earl Bonovich]

I'm just curious, is MPEG4 the best format to use when it comes to PQ and size? How does XVID or DIVX compare?

XVID and DIVX are names of codec based on MPEG-4