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nx_h264_deblock.nx

buildroot/runtime/nx_h264_deblock.nx

7445 B177 linesdepth 2pulls 2 transitivereach 8 importersview sourcekind librarytopic h264

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nx_h264_deblock.nx -- H.264 in-loop deblocking, normal luma edge filter (spec 8.7.2.3) + the alpha/beta (Table 8-16) and tc0 (Table 8-17) threshold tables. Smooths block edges; this is the stage that was producing the <=1 pixel diffs vs ffmpeg at internal 4x4 edges. Edge line = [p3,p2,p1,p0,q0,q1,q2,q3] across the edge; the normal filter (bS 1..3) modifies p1,p0,q0,q1 in place. indexA/indexB = qP (filter offsets 0). filter if |p0-q0|<alpha && |p1-p0|<beta && |q1-q0|<beta ap=|p2-p0| aq=|q2-q0| ; tc = tc0 + (ap<beta) + (aq<beta) delta = Clip3(-tc,tc, ((q0-p0)*4 + (p1-q1) + 4) >> 3) p0+=delta ; q0-=delta (clip 0..255) if ap<beta: p1 += Clip3(-tc0,tc0,(p2 + ((p0o+q0o+1)>>1) - 2*p1)>>1) if aq<beta: q1 += Clip3(-tc0,tc0,(q2 + ((p0o+q0o+1)>>1) - 2*q1)>>1) genealogy_id: itu_t_h264_sec8_7_deblocking + table8_16_alpha_beta + table8_17_tc0 lineage_id: normal_luma_edge_filter + threshold_tables license_tier: ORIGINAL

dependencies 1 imports · 6 importers

imports: nx_syscalls.nx

imported by: nx_h264_brecon.nxnx_h264_deblock_gate.nxnx_h264_decode_frame.nxnx_h264_pframe_recon.nxnx_h264_slice_extract.nxnx_vdeblock.nx

structs

none

consts

none

functions

20	func db_asr(x: i64, n: i64) -> i64 called by 2: nx_deblock_luma_edge nx_deblock_chroma_edge
25	func db_clip3(lo: i64, hi: i64, v: i64) -> i64 called by 2: nx_deblock_luma_edge nx_deblock_chroma_edge
30	func db_clip1(v: i64) -> i64 called by 2: nx_deblock_luma_edge nx_deblock_chroma_edge
35	func db_abs(v: i64) -> i64 { if v < 0 { return 0 - v } return v } called by 3: nx_deblock_luma_edge nx_deblock_luma_bs4 nx_deblock_chroma_edge
37	func nx_db_alpha(idx: i64) -> i64 called by 4: nx_deblock_luma_edge nx_deblock_luma_bs4 nx_deblock_chroma_edge main calls 1: sys_mmap
47	func nx_db_beta(idx: i64) -> i64 called by 4: nx_deblock_luma_edge nx_deblock_luma_bs4 nx_deblock_chroma_edge main calls 1: sys_mmap
58	func nx_db_tc0(bs: i64, idx: i64) -> i64 called by 3: nx_deblock_luma_edge nx_deblock_chroma_edge main calls 1: sys_mmap
80	func nx_deblock_luma_edge(s: *i64, bs: i64, qp: i64) -> i64 called by 6: deblock_luma_b main main deblock_luma_p main vc_deblock_frame calls 7: nx_db_alpha nx_db_beta nx_db_tc0 db_abs db_clip3 db_asr+1
111	func nx_deblock_luma_bs4(s: *i64, qp: i64) -> i64 called by 3: deblock_luma_b main deblock_luma_p calls 3: nx_db_alpha nx_db_beta db_abs
156	func nx_deblock_chroma_edge(s: *i64, bs: i64, qp: i64) -> i64 called by 3: deblock_chroma_b main deblock_chroma_p calls 7: nx_db_alpha nx_db_beta db_abs nx_db_tc0 db_clip3 db_asr+1