diff options
| -rw-r--r-- | va/va.h | 27 |
1 files changed, 25 insertions, 2 deletions
@@ -2028,10 +2028,33 @@ typedef struct _VAEncMiscParameterRIR uint32_t va_reserved[VA_PADDING_LOW]; } VAEncMiscParameterRIR; +/** HRD / VBV buffering parameters for encoding. + * + * This sets the HRD / VBV parameters which will be used by the rate + * controller for encoding. It should be specified in modes using a bitrate + * target when the buffering of the output stream needs to be constrained. + * + * If not provided, the encoder may use arbitrary amounts of buffering. + */ typedef struct _VAEncMiscParameterHRD { - uint32_t initial_buffer_fullness; /* in bits */ - uint32_t buffer_size; /* in bits */ + /** The initial fullness of the HRD coded picture buffer, in bits. + * + * This sets how full the CPB is when encoding begins - that is, how much + * buffering will happen on the decoder side before the first frame. + * The CPB fullness will be reset to this value after any rate control + * reset (a change in parameters or an explicit reset). + * + * For H.264, it should match the value of initial_cpb_removal_delay in + * buffering_period SEI messages. + */ + uint32_t initial_buffer_fullness; + /** The HRD coded picture buffer size, in bits. + * + * For H.264, it should match the value of cpb_size_value_minus1 in the VUI + * parameters. + */ + uint32_t buffer_size; /** \brief Reserved bytes for future use, must be zero */ uint32_t va_reserved[VA_PADDING_LOW]; |