By Pradeep Ramachandran
1) x265 can now refine analysis from a previous HEVC encode (using options –refine-inter, and –refine-intra), or a previous AVC encode (using option –refine-mv-type). The previous encode’s information can be packaged using the x265_analysis_data_t data field available in the x265_picture object.
2) Basic support for segmented (or chunked) encoding added with –vbv-end that can specify the status of CPB at the end of a segment. String this together with –vbv-init to encode a title as chunks while maintaining VBV compliance!
3) –force-flush can be used to trigger a premature flush of the encoder. This option is beneficial when input is known to be bursty, and may be at a rate slower than the encoder.
4) Experimental feature –lowpass-dct that uses truncated DCT for transformation.
1) Slice-parallel mode gets a significant boost in performance, particularly in low-latency mode.
2) x265 now officially supported on VS2017.
3) x265 now supports all depths from mono0 to mono16 for Y4M format.
1) Options that modified PPS dynamically (–opt-qp-pps and –opt-ref-list-length-pps) are now disabled by default to enable users to save bits by not sending headers. If these options are enabled, headers have to be repeated for every GOP.
2) Rate-control and analysis parameters can dynamically be reconfigured simultaneously via the x265_encoder_reconfig API.
3) New API functions to extract intermediate information such as slice-type, scenecut information, reference frames, etc. are now available. This information may be beneficial to integrating applications that are attempting to perform content-adaptive encoding. Refer to documentation on x265_get_slicetype_poc_and_scenecut, and x265_get_ref_frame_list for more details and suggested usage.
4) A new API to pass supplemental CTU information to x265 to influence analysis decisions has been added. Refer to documentation on x265_encoder_ctu_info for more details.
1) Bug fixes when –slices is used with VBV settings.
2) Minor memory leak fixed for HDR10+ builds, and default x265 when pools option is specified.
3) HDR10+ bug fix to remove dependence on poc counter to select meta-data information.