Opened 8 years ago

Closed 8 years ago

#1154 closed task (invalid)

something about about sps_max_dec_pic_buffering_minus1

Reported by: charles.lee Owned by:
Priority: minor Milestone: HM-12.1
Component: HM Version: HM-12.0
Keywords: Cc: fbossen, ksuehring, davidf, jct-vc@…

Description

In the hevc specification about sps_max_dec_pic_buffering_minus1,
it wrote "The value of sps_max_dec_pic_buffering_minus1[ i ] shall be less than or
equal to vps_max_dec_pic_buffering_minus1[ i ] for each value of i " .but i think the two parameter will be equal for rach value of i , i have a doubt abut it ? who can explain it?

Change History (4)

comment:1 Changed 8 years ago by DefaultCC Plugin

  • Cc fbossen ksuehring davidf jct-vc@… added

comment:2 follow-up: Changed 8 years ago by adarsh

Another way of looking at this is the following: the value of vps_max_dec_pic_buffering_minus1[ i ] in a VPS shall be greater than or equal to the value of sps_max_dec_pic_buffering_minus1[ i ] in any SPS that refers to this VPS.

Consider a bitstream containing two coded video sequences - CVS1 followed (in decoding order) by CVS2. Let SPS1 and SPS2 (not the same) be the respective SPS for CVS1 and CVS2. Let both the SPSs refer to the same VPS. Now, if the value of sps_max_dec_pic_buffering_minus1[ i ] is equal to 4 in SPS1 and equal to 5 in SPS2, respectively, the value of vps_max_dec_pic_buffering_minus1[ i ] shall be 5 or greater (but cannot equal 4).

You could have a case/bitstream where the value signaled for the vps_max_dec_pic_buffering_minus1[ i ] is equal to sps_max_dec_pic_buffering_minus1[ i ] for each i, in which case all the SPS that refer to same VPS have the same value for sps_max_dec_pic_buffering_minus1[ i ]. But, it is not the only possibility - as shown in the example above.

comment:3 in reply to: ↑ 2 Changed 8 years ago by charles.lee

OK ,I have get it! thank you adarsh。

Replying to adarsh:

Another way of looking at this is the following: the value of vps_max_dec_pic_buffering_minus1[ i ] in a VPS shall be greater than or equal to the value of sps_max_dec_pic_buffering_minus1[ i ] in any SPS that refers to this VPS.

Consider a bitstream containing two coded video sequences - CVS1 followed (in decoding order) by CVS2. Let SPS1 and SPS2 (not the same) be the respective SPS for CVS1 and CVS2. Let both the SPSs refer to the same VPS. Now, if the value of sps_max_dec_pic_buffering_minus1[ i ] is equal to 4 in SPS1 and equal to 5 in SPS2, respectively, the value of vps_max_dec_pic_buffering_minus1[ i ] shall be 5 or greater (but cannot equal 4).

You could have a case/bitstream where the value signaled for the vps_max_dec_pic_buffering_minus1[ i ] is equal to sps_max_dec_pic_buffering_minus1[ i ] for each i, in which case all the SPS that refer to same VPS have the same value for sps_max_dec_pic_buffering_minus1[ i ]. But, it is not the only possibility - as shown in the example above.

comment:4 Changed 8 years ago by ksuehring

  • Resolution set to invalid
  • Status changed from new to closed
Note: See TracTickets for help on using tickets.

This list contains all users that will be notified about changes made to this ticket.

These roles will be notified: Reporter, Owner, Subscriber, Participant

  • Adarsh Krishnan Ramasubramonian(Participant)
  • charles(Reporter, Participant)
  • David Flynn(Subscriber)
  • Frank Bossen(Subscriber)
  • jct-vc@…(Subscriber)
  • karl.sharman@…(Always)
  • Karsten Suehring(Subscriber, Participant, Always)