{
  "artifact_id": "L2-003",
  "layer": "L2",
  "registration_tier": "founder_vetted",
  "parent_l1": "L1-003",
  "principle_ref": "sha256:<L1-003_principle_hash>",
  "title": "CASSI Mismatch-Only Spec (KAIST benchmark family)",
  "spec_type": "mismatch_only",
  "six_tuple": {
    "omega": {
      "H": [
        64,
        2048
      ],
      "W": [
        64,
        2048
      ],
      "N_bands": [
        8,
        128
      ],
      "mask_density": [
        0.3,
        0.7
      ],
      "noise_level": [
        0.001,
        0.1
      ],
      "disp_a1_error": [
        0.0,
        0.05
      ],
      "disp_alpha_error": [
        0.0,
        0.3
      ],
      "mask_dx": [
        0.0,
        1.0
      ],
      "mask_dy": [
        0.0,
        1.0
      ],
      "mask_theta": [
        0.0,
        0.15
      ]
    },
    "E": {
      "forward": "y(x,y) = sum_lambda C(x,y) * f(x, y + a*lambda, lambda) + n(x,y)",
      "operator": "cassi_forward",
      "primitive_chain": "L.broadcast.spectral -> L.diag.binary -> L.shear.spectral -> int.spectral",
      "inverse": "recover f in R^{H x W x N_bands} from a single 2D snapshot y"
    },
    "B": {
      "nonnegativity": true,
      "spectral_smoothness": true,
      "mask_binary": "C(x,y) in {0,1}"
    },
    "I": {
      "strategy": "zero_init"
    },
    "O": [
      "per_channel_PSNR",
      "SSIM",
      "SAM_deg",
      "residual_norm",
      "convergence_curve"
    ],
    "epsilon_fn": "25.0 + 2.0 * log2(H / 64) + 1.5 * log10(photon_count / 50)"
  },
  "protocol_fields": {
    "input_format": {
      "measurement": "float32(H, W + a*N_bands)",
      "mask": "bool(H, W)"
    },
    "output_format": {
      "spectral_cube": "float32(H, W, N_bands)"
    },
    "baselines": [
      {
        "name": "GAP-TV",
        "method_sig": "L+O",
        "expected_psnr": 24.5
      },
      {
        "name": "ADMM-CASSI",
        "method_sig": "L+O",
        "expected_psnr": 26.8
      },
      {
        "name": "PnP-HSICNN",
        "method_sig": "L+N",
        "expected_psnr": 30.2
      },
      {
        "name": "DIP-Spectral",
        "method_sig": "L+N",
        "expected_psnr": 23.0
      }
    ]
  },
  "ibenchmark_range": {
    "center_ibenchmark": {
      "rho": 1,
      "omega_tier": {
        "H": 256,
        "W": 256,
        "N_bands": 28,
        "mask_density": 0.5,
        "noise_level": 0.01,
        "disp_a1_error": 0.0,
        "disp_alpha_error": 0.0,
        "mask_dx": 0.0,
        "mask_dy": 0.0,
        "mask_theta": 0.0
      },
      "epsilon": 28.0
    },
    "tier_bounds": {
      "H": [
        64,
        1024
      ],
      "W": [
        64,
        1024
      ],
      "N_bands": [
        16,
        128
      ],
      "noise_level": [
        0.005,
        0.1
      ],
      "disp_a1_error": [
        0.0,
        0.05
      ],
      "disp_alpha_error": [
        0.0,
        0.2
      ],
      "mask_dx": [
        0.0,
        1.0
      ],
      "mask_dy": [
        0.0,
        1.0
      ],
      "mask_theta": [
        0.0,
        0.15
      ]
    },
    "proximity_threshold": 0.1
  },
  "d_spec": 0.45,
  "d_spec_notes": "Reference distance from the oracle-assisted CASSI spec is d_spec ~= 0.17 (Similar band); this spec is the canonical mismatch-only baseline and sits at the centroid of the CASSI spec family.",
  "s1_s4_gates": [
    "PASS",
    "PASS",
    "PASS",
    "PASS"
  ],
  "s1_s4_justifications": {
    "S1": "Dimensions: mask C in {0,1}^{H x W} matches spatial grid; shear a*N_bands fits detector width budget; 4 DAG nodes are dimensionally consistent from cube to 2D snapshot.",
    "S2": "Binary random mask at 50% fill satisfies RIP-like conditions for N_bands <= 128; compound operator kappa_eff <= 200 across Omega with regularization.",
    "S3": "GAP-TV, ADMM, PnP all provably converge for CASSI with rate q=2.0; monotone decrease of residual norm confirmed empirically on KAIST benchmark.",
    "S4": "epsilon_fn evaluates across 50 random Omega samples without error; no baseline passes epsilon_fn everywhere (hardness rule satisfied)."
  },
  "ipfs_cid": null,
  "display_slug": "cassi"
}