VDEC Performance Specifications
The
Performance Specifications
This section describes only the performance specifications of the Ascend AI Processor of each product, which may differ based on the memory and CPU configurations of the respective product. For details about the product performance specifications, see the official descriptions at the Ascend community.
This section takes a single Ascend AI Processor as an example to describe the performance specifications in basic scenarios, as shown in the table below. The performance at other resolutions can be estimated in the same way.
In the following table, one channel corresponds to one thread, 720p indicates a resolution of 1280 × 720 pixels, 1080p indicates a resolution of 1920 × 1080 pixels, and 4K indicates a resolution of 3840 × 2160 pixels.
Scenario |
Total Frame Rate |
|---|---|
n-channel 720p (1 ≤ n ≤ 12) |
n × 480 FPS For Atlas 300V video analysis cards, when 1 < n ≤ 12, the total frame rate is n × 400 FPS. |
n-channel 720p (n > 12) |
5760 FPS For Atlas 300V video analysis cards, when n > 12, the total frame rate is 4800 FPS. |
n-channel 1080p (1 ≤ n ≤ 12) |
n × 240 FPS For Atlas 300V video analysis cards, when 1 < n ≤ 12, the total frame rate is n × 200 FPS. |
n-channel 1080p (n > 12) |
2880 FPS For Atlas 300V video analysis cards, when n > 12, the total frame rate is 2400 FPS. |
n-channel 4K (1 ≤ n ≤ 12) |
n × 60 FPS |
n-channel 4K (n > 12) |
720 FPS |
Scenario |
Total Frame Rate |
|---|---|
n-channel 720p (1 ≤ n ≤ 4) |
n x 600 FPS |
n-channel 720p (n > 4) |
2400 FPS |
n-channel 1080p (1 ≤ n ≤ 4) |
n x 300 FPS |
n-channel 1080p (n > 4) |
1200 FPS |
n-channel 4K (1 ≤ n ≤ 4) |
n x 75 FPS |
n-channel 4K (n > 4) |
300 FPS |
Scenario |
Total Frame Rate |
|---|---|
n-channel 720p (1 ≤ n ≤ 2) |
n × 480 FPS |
n-channel 720p (n > 2) |
960 FPS |
n-channel 1080p (1 ≤ n ≤ 2) |
n × 240 FPS |
n-channel 1080p (n > 2) |
480 FPS |
n-channel 4K (1 ≤ n ≤ 2) |
n × 60 FPS |
n-channel 4K (n > 2) |
120 FPS |
The following table uses 1080p input streams as an example to describe the formula for calculating the maximum buffer used by each VDEC channel. The buffer usage is calculated as follows:
- Buffer size for the input streams: ≥ 3/4 of the decoding channel size (width x height).
- Frame buffer size for the decoded images: Call hi_vdec_get_pic_buf_size to obtain the value, which is related to the input stream resolution.
- Temporal motion vector (TMV) buffer size for the decoded images: Call hi_vdec_get_tmv_buf_size to obtain the value, which is related to the input stream resolution.
- The preceding buffer sizes and the number of reference frames should be set after the hi_mpi_vdec_create_chn call.
- The number of buffered frames after decoding should be set after the hi_mpi_vdec_set_chn_param call.
Formula |
Scenario |
Memory Usage |
|---|---|---|
6 MB + Buffer size for the input streams x 2 + (Frame buffer size for the decoded images + TMV buffer size for the decoded images) x (Number of reference frames + Number of buffered frames after decoding + 1) |
|
52.5 MB (eight reference frames) 31.5 MB (two reference frames) |
|
58 MB (eight reference frames) 34 MB (two reference frames) |