CMA Size Requirements - 2024.1 English - PG252

H.264/H.265 Video Codec Unit v1.2 Solutions LogiCORE IP Product Guide (PG252)
Document ID
PG252
Release Date
2024-05-30
Version
2024.1 English

The following table contains theoretical contiguous memory access (CMA) buffer requirements for the VCU encoder/decoder based on resolution and format. The sizes below correspond to one instance of the encoder or decoder. Multiply these by number of streams for multistream use cases. Other elements such as kmssink/v4l2src typically increase the CMA requirements by an additional 10 to 15%.

Table 1. VCU Encoder CMA Requirements
Resolution 4:2:2 10-bit AVC 1 4:2:2 10-bit HEVC 2 4:2:2: 8-bit AVC 1 4:2:2: 8-bit HEVC 2 4:2:0 10-bit AVC 1 4:2:0 10-bit HEVC 2 4:2:0 8-bit AVC 1 4:2:0 8-bit HEVC 2
3840×2160 (MB) 3 294 199 248 155 243 151 208 117
1920×1080 (MB) 54 52 42 40 42 40 32 31
1280×720 (MB) 27 26 21 20 20 19 17 16
  1. AVC requires extra intermediate buffers when it is using multiple-cores. Unlike HVEC, the AVC standard does not support Tile processing, so to exploit data processing parallelism it requires two intermediate buffers.
  2. VCU AVC Encoder uses multiple cores when resolution is >= 1080p60, that is reason for having ~100 MB delta between HEVC and AVC CMA requirements for 3840x2160.
  3. Includes memory for two intermediate buffers.