1 Hybrid Bit-stream Models

2 Hybrid bit-stream model: Type 1  Pros: Simple. All we need are open-source codecs.  Cons: May lose some available information which is present at the receiver.

3 Hybrid bit-stream model: Type 2  Pros: Still simple. All we need are open-source codecs and open-source packetizer/depacketizer. Some codecs already incorporate packetizer/depacketizer.  Cons: May lose some available information present at the receiver.

4 Hybrid bit-stream model: Type 3  Proposed by Mr. Osamu Sugimoto.  A model can use all available information by allowing the model to use any bit-stream data.  We need open-source for all components. Source Contents Video Audio (Data) Video Encoder Audio Encoder Encoder Packetizer PES MUX Packet video (Multiplexed) Error Correction (FEC) (packet Reordering) interleaving IP Packetizer (Or Modulation for Air-transmission) (Channel) 204 bytes 1500 bytes Several Muxed A/V packets In one IP packet TS ES

5 Bottom lines  All components should have open-source programs.  If proponents of ILGs propose to use particular bit- stream data, they should provide source codes to read such bit-stream data.  If proponents of ILGs propose to use a particular codec, they should provide source codes for the codec.  A model will be given bit-stream data and raw PVS data which will be used for subjective testing. FR and RR models will be given additional data.  The project should be done in a timely manner.

6 Things to be determined  Codec types: Should be open-sources  MPEG4, H.264, etc.  Which codec do we want to do first?  Test conditions  Are we going to use the same test conditions of the multimedia testplan with minor changes (as little as possible)?  All test conditions in the multimedia testplan would be admissible if the corresponding bit-stream data is available.  Subjective testing  Option 1: Proponents and ILGs  Pros: More test conditions  Cons: Difficult to. Can delay the whole process significantly.  We may not afford to spend years to develop Recommendations.  Option 1: ILGs only  Pros: Can be done timely and professionally.  Cons: smaller test conditions

7 Time Schedule  We may not afford to spend years to finish the project.  Industry needs good objective models immediately and other companies are introducing their products to the market.  A proposed schedule (ambitious ?)  Approval of testplan (by next VQEG meeting): Most works should be done through reflector. Editorial works can be shared by co-chairs and other volunteers.  Submission of models: 6 months after the approval of the testplan.  This technology improves rapidly and does not require backward comparability. We might have to be prepared to revise the standards when more promising technologies are available.