Content for TR 26.996 Word version: 18.1.0
7 ISAR solution properties
7.1 ISAR Baseline properties
7.1.1 Introduction
7.1.2 Physical properties of ISAR baseline in comparison to design constraints
7.1.4 Supported functional features in relation to functional design constraints
7 ISAR solution properties p. 24
7.1 ISAR Baseline properties p. 24
7.1.1 Introduction p. 24
The properties of the ISAR baseline are best characterized by comparing the reported properties of the selected split rendering solution against the design constraints. The design constraints are specified in clauses 6 (Physical Design Constraints) and 7 (Functional Design Constraints) of TR 26.865.
To that end, in the following, relevant excerpts of the ISAR selection deliverable on compliance with design constraints are provided. The full deliverables document is provided in the electronic attachment of this TR for reference, e.g., to help understanding how the solution properties were determined.
7.1.2 Physical properties of ISAR baseline in comparison to design constraints p. 24
The following Table 7.1-1 displays the physical properties of the ISAR baseline in relation to the physical design constraints:
| Physical attribute | Constraint | Measured values based on "isar_selection_branch"(1 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Complexity of operation in end-rendering lightweight device | The complexity of operation in end-rendering lightweight device shall not exceed 80+(DOF*20) wMOPS.
0DOF: 80
1DOF: 100 2DOF: 120 3DOF: 140 | 3DOF (with LC3plus): max 73.66, avg 70.7
3DOF (with LCLD): max 60.96, avg 51.41 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Complexity of operation at capable device/node | The complexity of operation at pre-rendering device/node shall be characterized. | IVAS decoder + 3DOF split pre-rendering with LC3plus (MC714): max 1063.97, avg 1037.15 IVAS decoder + 3DOF split pre-rendering with LC3plus (ISM4): max 864.88, avg 854.2 IVAS decoder + 3DOF split pre-rendering with LCLD (HOA3): max 925.5, avg 837.0 IVAS decoder + 3DOF split pre-rendering with LCLD (MASA2): max 662.12, avg 653.06 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Memory footprint of operation in end-rendering lightweight device | The RAM consumption shall not exceed 100+(DOF*50) kWords.
0DOF: 100 kWords
1DOF: 150 kWords 2DOF: 200 kWords 3DOF: 250 kWords The ROM (PROM and table ROM) shall not exceed 150 kWords. | (word = 4 Bytes)
RAM (heap + stack):
3DOF (with LC3plus): 67.51 kWords 3DOF (with LCLD): 67.87 kWords PROM (lc3plus + lib_isar + lcld): 20.04 kWords TROM (lc3plus + lib_isar + lcld): 42.14 kWords | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Memory footprint of operation at pre-rendering device/node | The memory footprint of operation at pre-rendering device/node shall be characterized. | RAM: IVAS decoder + 3DOF split pre-rendering with LC3plus (MC714): 586.751 kWords IVAS decoder + 3DOF split pre-rendering with LC3plus (ISM4): 393.24 kWords IVAS decoder + 3DOF split pre-rendering with LCLD (HOA3): 467.63 kWords IVAS decoder + 3DOF split pre-rendering with LCLD (MASA2): 290.39 kWords PROM (lib_com + lib_dec + lib_rend):172.6 kWords TROM (lib_com + lib_dec + lib_rend):156.4 kWords | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Algorithmic motion-to-sound latency in head-tracked rendering operation | 0-DOF: no constraint 1-DOF: 30 ms for rotations around corrected axis (in post rendering), for other axes no constraints 2-DOF: 30 ms for rotations around corrected axes (in post rendering), for the remaining axis no constraint 3-DOF: 30 ms for rotations around all axes (in post rendering) | 2.5ms <= Algorithmic motion-to-sound latency <= 22.5 ms | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Algorithmic audio delay | The total algorithmic end-to-end audio delay including IVAS algorithmic delay shall not exceed 50 ms. |
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Bit rate of coded intermediate representation | The Split Rendering solution should offer 3-DOF operation at multiple bit rates with rate switching support and shall at least offer operation at 768 kbps. For 3-DOF operation, 384 kbps and 512 kbps should be offered in addition to the required 768 kbps. For 1-DOF operation, 256 kbps should be offered. For 0-DOF operation, 256 kbps and even lower bit rates should be offered. For cases with high transmission channel capacities, high bit rate operation modes > 768 kbps may be offered if QoE gains can be demonstrated. |
|
7.1.4 Supported functional features in relation to functional design constraints p. 28
The following Table 7.1-2 lists supported functional features of the ISAR baseline in relation to the functional design constraints.
| Functional attribute | Constraint | Supported/Unsupported |
|---|---|---|
| Immersive audio formats of native coding format | All required immersive IVAS encoder input formats according to Pdoc IVAS-4 shall be supported. IVAS stereo input format should be supported for 0-DOF operation. | Supported:
SBA MC ISM MASA OSBA OMASA Unsupported: Stereo |
| Bit rates of required immersive audio coding modes of native coding format | All required bit rates of IVAS immersive operation modes according to Pdoc IVAS-4 shall be supported. All IVAS stereo bit rates should be supported for 0-DOF operation. | Supported:
All bitrates supported for immersive formats Unsupported: Stereo |
| Head-trackability of immersive audio formats | The head-trackability of the immersive audio formats of the native coding format shall be retained. Preservation of the DOF level is the objective, reduced DOF levels may be provided. | Supported |
| Packet loss concealment (PLC) | A PLC solution shall be provided. | Supported |
| Non-diegetic audio support | The solution shall support (1DOF - 3DOF) diegetic audio and (0-DOF) one-channel non-diegetic audio and two-channel (stereo or binaural) non-diegetic audio. It shall be possible to overlay post rendered audio obtained from instances operated with diegetic and non-diegetic audio. | Supported |
