nx_vcodec_t8feat_gate.nx source

1import "nx_gate_base.nx" 2// nx_vcodec_t8feat_gate.nx -- FEATURE-PRESERVATION proof for the t8 stream (field 786/787 "still blocky / 3// low quality", root-caused): an MB that is 90% flat skin + one small high-contrast feature (eye, nostril, 4// mouth corner) has LOW mean mad -> the old policy sent it 8x8 -> the feature's energy spread across many 5// sub-deadzone 8x8 coefficients -> detail VANISHED while whole-frame PSNR barely moved (the metric the old 6// gates watched). This gate measures what the EYE watches: SSE restricted to +-3px windows around every 7// planted feature (featSSE), t8 stream vs legacy, on smooth-skin content with a moving grid of 3x3 dark 8// features + a mouth line, at the coarse end of the live ladder (qp 28/40). GREEN iff the t8 stream's 9// featSSE stays within 115% of legacy at every qp (the vc_mb_t8_ok uniform-flatness guard keeps feature 10// MBs on 4x4) AND every frame decodes bit-exact. license_tier: ORIGINAL 11import "nx_syscalls.nx" 12import "nx_video_codec_wasm.nx" 13 14const FW: i64 = 256 15const FH: i64 = 192 16 17func grow(name: *u8, ok: i64) -> i64 { if ok==1 { gw(" PASS " as *u8) } else { gw(" FAIL " as *u8) } gw(name); gw(" 18" as *u8); return ok } 19func gn(v: i64) -> i64 { 20 let b: *u8=sys_mmap(28); var m: i64=v; if m<0{sys_write(1,"-" as *u8,1);m=0-m} 21 let t: *u8=sys_mmap(28); var k: i64=0; if m==0{t[0]=48 as u8;k=1} while m>0{t[k]=(48+(m%10)) as u8;m=m/10;k=k+1} 22 var i: i64=0; while i<k{b[i]=t[k-1-i];i=i+1} sys_write(1,b,k); return 0 } 23func eqb(a: *u8, b: *u8, n: i64) -> i64 { var i: i64=0; while i<n { if (a[i]&0xff)!=(b[i]&0xff) { return 0 } i=i+1 } return 1 } 24func cpb(d: *u8, s: *u8, n: i64) -> i64 { var i: i64=0; while i<n { d[i]=s[i]; i=i+1 } return 0 } 25 26// smooth skin + a moving grid of small dark features (eye class) + a 2px mouth line; chroma flat 27func fill_face(yuv: *u8, sh: i64) -> i64 { 28 let N: i64=FW*FH; let C2: i64=(FW/2)*(FH/2) 29 var r: i64=0 30 while r<FH { var c: i64=0 31 while c<FW { yuv[r*FW+c]=(105 + (c+r)/8) as u8; c=c+1 } r=r+1 } 32 var fy: i64 = 24 33 while fy < FH - 8 { 34 var fx: i64 = 24 35 while fx < FW - 8 { 36 let cx: i64 = fx + sh*2 37 let cy: i64 = fy + sh 38 var dy: i64 = 0 - 1 39 while dy <= 1 { var dx: i64 = 0 - 1 40 while dx <= 1 { yuv[(cy+dy)*FW + cx+dx] = 45 as u8; dx = dx + 1 } dy = dy + 1 } 41 fx = fx + 48 42 } 43 fy = fy + 48 44 } 45 var mx: i64 = FW/2 - 10 46 while mx < FW/2 + 10 { yuv[(FH/2 + sh)*FW + mx] = 60 as u8; yuv[(FH/2 + sh + 1)*FW + mx] = 60 as u8; mx = mx + 1 } 47 var i: i64=0 48 while i<C2 { yuv[N+i]=120 as u8; yuv[N+C2+i]=135 as u8; i=i+1 } 49 return 0 } 50 51// SSE inside +-3px windows around every planted feature (same grid math as fill_face) 52func feat_sse(dec: *u8, src: *u8, sh: i64) -> i64 { 53 var sse: i64 = 0 54 var fy: i64 = 24 55 while fy < FH - 8 { 56 var fx: i64 = 24 57 while fx < FW - 8 { 58 let cx: i64 = fx + sh*2 59 let cy: i64 = fy + sh 60 var dy: i64 = 0 - 3 61 while dy <= 3 { var dx: i64 = 0 - 3 62 while dx <= 3 { 63 let d: i64 = (dec[(cy+dy)*FW + cx+dx] & 0xff) - (src[(cy+dy)*FW + cx+dx] & 0xff) 64 sse = sse + d*d 65 dx = dx + 1 } dy = dy + 1 } 66 fx = fx + 48 67 } 68 fy = fy + 48 69 } 70 return sse } 71 72func seedctx(rctx: *i64, est: *i64, probs: *i64, rcbuf: *u8, t8c: *i64) -> i64 { 73 rctx[0]=0; rctx[1]=est as i64; rctx[2]=probs as i64; rctx[3]=rcbuf as i64; rctx[4]=t8c as i64 74 rctx[5]=0; rctx[6]=0; rctx[7]=0; return 0 } 75 76// 4-frame chain; kind 0=legacy 1=t8. out[0]=featSSE(last frame), out[1]=exact 77func run_face(qp: i64, kind: i64, bufs: *i64, out: *i64) -> i64 { 78 let N: i64=FW*FH; let C2: i64=(FW/2)*(FH/2); let sz: i64=N+2*C2 79 let cur: *u8 = bufs[12] as *u8 80 let prevE: *u8 = bufs[0] as *u8 81 let reconE: *u8 = bufs[1] as *u8 82 let prevD: *u8 = bufs[2] as *u8 83 let reconD: *u8 = bufs[3] as *u8 84 let wire: *u8 = bufs[4] as *u8 85 let blk: *i64 = bufs[5] as *i64 86 let mv: *i64 = bufs[6] as *i64 87 let est: *i64 = bufs[7] as *i64 88 let probs: *i64 = bufs[8] as *i64 89 let rcbuf: *u8 = bufs[9] as *u8 90 let t8c: *i64 = bufs[10] as *i64 91 let rctx: *i64 = bufs[11] as *i64 92 var z: i64=0 93 while z<sz { prevE[z]=0 as u8; prevD[z]=0 as u8; z=z+1 } 94 var exact: i64=0 95 var f: i64=0 96 var fs: i64=0 97 while f<4 { 98 fill_face(cur, f) 99 var key: i64=0 100 if f==0 { key=1 } 101 var nb: i64=0 102 if kind==1 { seedctx(rctx, est, probs, rcbuf, t8c) 103 nb = vv_enc_t8(cur, prevE, reconE, FW, FH, qp, key, qp*188, wire, 2097152, blk, mv, rctx) } 104 else { nb = vv_enc(cur, prevE, reconE, FW, FH, qp, key, qp*188, wire, 2097152, blk, mv) } 105 if nb <= 0 { out[0]=0; out[1]=exact; return 0-1 } 106 if kind==1 { seedctx(rctx, est, probs, rcbuf, t8c) 107 vv_dec_t8(prevD, reconD, FW, FH, qp, wire, nb, blk, mv, rctx) } 108 else { vv_dec(prevD, reconD, FW, FH, qp, wire, nb, blk, mv) } 109 if eqb(reconD, reconE, sz)==1 { exact=exact+1 } 110 fs = feat_sse(reconD, cur, f) 111 cpb(prevE, reconE, sz) 112 cpb(prevD, reconD, sz) 113 f=f+1 114 } 115 out[0]=fs 116 out[1]=exact 117 return 0 } 118 119func main() -> i64 { 120 gw("=== nx_vcodec_t8feat_gate: small-feature preservation (the pixels the EYE watches), t8 vs legacy ===\n" as *u8) 121 let N: i64=FW*FH; let C2: i64=(FW/2)*(FH/2); let sz: i64=N+2*C2 122 let bufs: *i64 = sys_mmap(16*8) as *i64 123 bufs[0]=sys_mmap(sz+64) as i64 124 bufs[1]=sys_mmap(sz+64) as i64 125 bufs[2]=sys_mmap(sz+64) as i64 126 bufs[3]=sys_mmap(sz+64) as i64 127 bufs[4]=sys_mmap(2097152) as i64 128 bufs[5]=sys_mmap(512) as i64 129 bufs[6]=sys_mmap(128) as i64 130 bufs[7]=sys_mmap(64) as i64 131 bufs[8]=sys_mmap(32*8) as i64 132 bufs[9]=sys_mmap(1048576) as i64 133 bufs[10]=sys_mmap(5120) as i64 134 bufs[11]=sys_mmap(64) as i64 135 bufs[12]=sys_mmap(sz+64) as i64 136 vc_t8_init(bufs[10] as *i64) 137 let oL: *i64=sys_mmap(32) as *i64 138 let oT: *i64=sys_mmap(32) as *i64 139 let qs: *i64=sys_mmap(32) as *i64 140 qs[0]=20; qs[1]=28; qs[2]=40 141 var pass: i64=0 142 var total: i64=0 143 var qi: i64=0 144 while qi<3 { 145 run_face(qs[qi], 0, bufs, oL) 146 run_face(qs[qi], 1, bufs, oT) 147 gw(" qp=" as *u8); gn(qs[qi]) 148 gw(" featSSE legacy=" as *u8); gn(oL[0]); gw(" t8=" as *u8); gn(oT[0]) 149 gw(" (" as *u8); gn(oT[0]*100/oL[0]); gw("%) exact=" as *u8); gn(oT[1]); gw("/4\n" as *u8) 150 total=total+1 151 if oT[1]==4 { pass=pass+1 } 152 total=total+1 153 if oT[0] <= (oL[0]*115)/100 { pass=pass+1 } // features must survive the t8 stream 154 qi=qi+1 155 } 156 gw("T8FEAT: " as *u8); gn(pass); gw("/" as *u8); gn(total) 157 if pass==total { gw(" GREEN -- the uniform-flatness guard keeps detail: feature MBs stay 4x4\n" as *u8); return 0 } 158 gw(" RED\n" as *u8); return 1 }