Hi, I took to the ##intel-media IRC to find out why VAEncMiscParameterMaxSliceSize has no effect for the VAAPI hevc encoder. Unfortunately, jkqxz let me know the parameter is simply not implemented. The VAEncMiscParameterMaxSliceSize parameter is documented in va.h, so I assume there is a plan to implement this feature at some point. I'm hoping it could be done sooner than later. Limiting hevc slice size greatly improves error resiliency when streaming via RTP over a lossy network. The VAAPI hevc encoder is my encoder of choice for a number of reasons; albeit, without the ability to limit slice size, I will have to rely on NVENC, which provides the ability to limit slice size. va.h: /** * Allow a maximum slice size to be specified (in bits). * The encoder will attempt to make sure that individual slices do not exceed this size * Or to signal applicate if the slice size exceed this size, see "status" of VACodedBufferSegment */ typedef struct _VAEncMiscParameterMaxSliceSize { uint32_t max_slice_size; /** \brief Reserved bytes for future use, must be zero */ uint32_t va_reserved[VA_PADDING_LOW]; } VAEncMiscParameterMaxSliceSize; Thanks! Best, Ryan