Functions and Restrictions

For the Atlas Training Series Product, this function is not supported.

Function Description

Video Encoder (VENC) encodes YUV420SP NV12/NV21 8-bit images into H.264/H.265 video streams.

Single-process and multi-thread scenarios are not supported on the Atlas 200/300/500 Inference Product.

Resolution Restrictions

  • Input resolution range:

    Version

    Resolution Range

    Atlas 200/300/500 Inference Product

    128 x 128 to 1920 x 1920

  • Output stream resolution:

    VENC only encodes images and does not change the image resolution. Therefore, the resolution of the output image is the same as that of the input image.

Restrictions on Stream/Image Formats, Width and Height Alignment, and Buffers

To implement the VENC function:

  • Input buffer

    Call acl.media.dvpp_malloc or acl.media.dvpp_free to allocate or free the input buffer on the device. The buffer lifetime is managed by the user. For details about the buffer size, see the formula in the following table.

  • Output buffer

    The output buffer is managed by the system.

For details about the definition of the input image format, see acldvppPixelFormat. For details about the concepts such as width stride and height stride, see Terminology.

Table 1 Restrictions on the image format, width and height alignment, and buffer size

Input Format

Input Width and Height

Input Width Stride, Height Stride, and Buffer Size

Output Format

YUV420SP NV12 8-bit

Width: Must be a multiple of 2.

Height: Must be a multiple of 2.

Width stride: Round up the width to the nearest multiple of 16.

The height stride does not need to be configured.

Buffer size (in bytes) = Width stride x Height stride x 3/2

  • H.264 BP/MP/HP
  • H.265 MP (slice streams only)

YUV420SP NV21 8-bit