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Section A.3. Definition of Levels for Synthetic Profiles

A.3. Definition of Levels for Synthetic Profiles

This section describes the MPEG-4 Visual levels for the profiles including only synthetic visual data. Note that the profiles including only texture object types are considered synthetic profiles here because the video texture coding tool was developed by the MPEG SNHC subgroup with the initial target of coding textures to map over 2D and 3D meshes.

Table A.1. Levels for the video profiles
Visual profileLevelTypical visual session sizeMax. number of objects[1]Max. number objects per typeMax. unique quant. tablesMax. VMV buffer size (MB units)[2]Max. VCV buffer size (MB)[3]VCV decoder rate (MB/s)[4]VCV boundary MB decoder rate (MB/s)[5]Max. total VBV buffer size (units of 16,384 bits)Max. VOL VBV buffer size (units of 16,384 bits)[6]Max. video packet length (bits)[7]Max. sprite size (MB units)Wavelet restrictionsMax. bit rate (kbit/s)Max. enhancement layers/object
Simple[8] L0QCIF11 × Simple1198991,485N.A.[9]10102,048N.A.N.A.64N.A.
SimpleL1QCIF44 × Simple1198991,485N.A.10102,048N.A.N.A.64N.A.
SimpleL2CIF44 × Simple17923965,940N.A.40404,096N.A.N.A.128N.A.
SimpleL3CIF44 × Simple179239611,880N.A.40408,192N.A.N.A.384N.A.
Advanced Real-Time SimpleL1QCIF44 × Simple or Adv. Real Time Simple1198991,485N.A.10108,192N.A.N.A.64N.A.
Advanced Real-Time SimpleL2CIF44 × Simple or Adv. Real-Time Simple17923965,940N.A.404016,384N.A.N.A.128N.A.
Advanced Real-Time SimpleL3CIF44 × Simple or Adv. Real-Time Simple179239611,880N.A.404016,384N.A.N.A.384N.A.
Advanced Real-Time SimpleL4CIF1616 × Simple or Adv. Real-Time Simple179239611,880N.A.808016,384N.A.N.A.2000N.A.
Simple ScalableL1CIF44 × Simple or Simple Scalable117824957,425N.A.40402,048N.A.N.A.1281 spatial or temporal enhancement layer
Simple Scalable[10]L2CIF44 × Simple or Simple Scalable1316879223,760N.A.40404,096N.A.N.A.2561 spatial or temporal enhancement layer
CoreL1QCIF44 × Core or Simple45941985,9402,97016164,096N.A.N.A.3841
CoreL2CIF1616 × Core or Simple42,37679223,76011,88080808,192N.A.N.A.2,0001
Advanced CoreL1QCIF44 × Core or Simple or Adv. Scalable Texture4594198594029701684096N.A.See Table A.53841
Advanced CoreL2CIF1616 × Core or Simple or Adv. Scalable Texture4237679223,76011,88080408,192N.A.See Table A.52,0001
Core ScalableL1CIF44 × Core or Simple or Core Scalable or Simple Scalable42,37679214,8507,42564644,096N.A.N.A.7681
Core ScalableL2CIF88 × Core or Simple or Core Scalable or Simple42,97099029,70014,85080804,096N.A.N.A.1,5001
Core ScalableL3CCIR6011616 × Core or Simple or Core Scalable or Simple Scalable412,9064,032120,96060,480808016,384N.A.N.A.4,0002
MainL2CIF1616 × Main or Core or Simple43,9601,18823,76011,88080808,1921,584Scalable Texture @L12,0001
MainL3CCIR 6013232 × Main or Core or Simple411,3043,24097,20048,60032032016,3846,480Scalable Texture @L115,0001
MainL41920 × 10883232 × Main or Core or Simple465,34416,320489,600244,80076076016,38465,280Scalable Texture @L238,4001
Advanced Coding EfficiencyL1CIF44 × Adv. Coding Efficiency or Core or Simple41,18879211,8805,94040408,192N.A.N.A.3841
Advanced Coding EfficiencyL2CIF1616 × Adv. Coding Efficiency or Core or Simple42,3761,18823,76011,88080808,192N.A.N.A.2,0001
Advanced Coding EfficiencyL3CCIR 6013232 × Adv. Coding Efficiency or Core or Simple49,7203,24097,20048,60032032016,384N.A.N.A.15,0001
Advanced Coding EfficiencyL41920 × 10883232 × Adv. Coding Efficiency or Core or Simple448,96016,320489,600244,80076076016,384N.A.N.A.38,4001
N-BitL2CIF1616 × Core or Simple or N-Bit42,37679223,76011,88080808,192N.A.N.A.2,0001

[1] Enhancement layers are not counted as separate objects.

[2] The maximum VMV buffer size is the bound on the memory (in macroblock units) which can be used by the VMV algorithm. This algorithm (see [MPEG4-2, subclause D.5]) models the pixel memory needed by the entire visual decoding process. This includes the memory needed for reference VOPs in the prediction of P-, B-, and S(GMC)-VOPs and the storage of the reconstructed VOPs until they are released by the decoder, plus the memory required to queue B-VOPs until composition occurs. For the profiles that contain more than one layer, the memory requirements include all base and enhancement layers. When belonging to different, overlapping objects, some of these macroblocks may overlay on the display; separate memory is required (prior to composition) in the VMV.

[3] The maximum VCV buffer size (cumulative over all layers of all VOs) is twice the maximum number of macroblocks per VOP in the profile and level combination except for the Simple, Simple Scalable (Level 1), and Advanced Real-Time Simple profiles. For the Simple and the Advanced Real-Time Simple profiles, this value is the maximum number of macroblocks per VOP. For the Simple Scalable profile (Level 1), it is 1.25 times the maximum number of macroblocks per VOP. The limit applies both to the VCV buffer and the boundary MB VCV buffer.

[4] The VCV decoder rate is the vcv_decoder_rate (H) referred to in [MPEG4-2, subclause D.4]; this parameter is the number of MB/s based on the typical spatial and temporal resolutions, as follows:

  • 1,485 MB/s corresponds to QCIF at 15 Hz

  • 5,940 MB/s corresponds to CIF at 15 Hz and also twice QCIF at 30 Hz

  • 11,880 MB/s corresponds to CIF at 30 Hz

  • 7,425 MB/s corresponds to 1.25 times CIF at 15 Hz

  • 23,760 MB/s corresponds to twice CIF at 30 Hz

  • 97,200 MB/s corresponds to twice ITU-R 601 at 30 Hz

  • 489,600 MB/s corresponds to twice 1920×1088 at 30 Hz

[5] The VCV boundary MB decoder rate column bounds the number of macroblocks containing nontrivial shape information (boundary, not transparent or opaque). The VCV boundary MB decoder rate constrains the total number of boundary MBs in all VOLs, concurrently. Note that the boundary macroblocks are added to both the VCV and boundary MB VCV buffers.

[6] The total (aggregated) vbv_buffer_size is the sum of the individual VBV buffer occupancies at any given time (in units of 16,384 bits) for all VOLs of all VOs. This total VBV size is limited by the profile and level.

[7] The maximum video packet length is defined as the maximum number of bits of data_partitioned_motion_shape_texture() in one video packet. The constraint applies only when the data-partitioning tool is enabled in the bitstream. When data partitioning is disabled, there is no limit on the video packet length.

[8] For Simple@Level 0, the following restrictions apply:

  • The maximum frame rate is 15 frames/s.

  • The maximum f_code is 1.

  • The intra_dc_vlc_threshold is 0.

  • The maximum horizontal luminance pixel resolution is 176 pels/line.

  • The maximum vertical luminance pixel resolution is 144 pels/VOP.

  • If AC/DC prediction is used, the following restriction applies: QP value will not be changed within a VOP (or within a video packet if video packets are used in a VOP). If AC/DC prediction is not used, there are no restrictions to changing QP value.

[9] Not Applicable.

[10] The conformance point for the base layer of the Simple Scalable profile is the Simple@L1 when Simple Scalable@L1 is used and Simple@L2 when Simple Scalable@L2 is used.



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