VDEC Functions and Restrictions

Function Description

Video Decoder (VDEC) decodes videos.

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

• Input stream format
  • H.264 BP/MP/HP level 5.1 YUV420 streams (Annex-B raw video streams only)
  • H.265 8-/10-bit level 5.1 YUV420 streams (Annex-B raw video streams only)
• Output image requirements:

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

  Output Format	Output Width and Height
  YUV420SP NV12 8bit	Width: Must be a multiple of 2. Height: Must be a multiple of 2.
  YUV420SP NV21 8bit	Width: Must be a multiple of 2. Height: Must be a multiple of 2.
  RGB888	No alignment requirement.
  BGR888	No alignment requirement.

  

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

Other Restrictions

• VDEC decodes streams input by frame.
• If there are bad frames or frame loss in the stream, VDEC will mark the frames as a decoding failure and report an exception.
• VDEC decodes only the H.264 8-bit streams encoded in interlaced mode.
• The combined use of stream feeding in frame mode and output in the decoding sequence enables both fast decoding and output. However, this is no applicable to streams containing B-frames.