Blends in (upper layer) onto in2 (lower layer) by mode, implementing the full Photoshop set of 27 blend modes (normal/dissolve/darken family/lighten family/overlay family/difference family/HSL family). opacity sets overall opacity. With device = auto the GPU compute path runs first and falls back to the mirrored CPU implementation on failure — identical results on any environment. Dissolve-mode noise is reproducible via seed.

Module：Layer blend · Task type：blend

Ports

Inputs

PortTypeRequired
inImage / cv::Mat✓
in2Image / cv::Mat✓

Outputs

PortTypeRequired
outtask_graph::Image✓

Parameters

参数类型默认值范围 / 选项说明
modeenum027 options (see list below)blend mode (27 options, listed below the table)
opacityfloat1[0, 1]opacity of the blended result
deviceenum0auto / gpu / cpuexecution device: auto = GPU first, falling back to the mirrored CPU implementation
seedint42[0, 2147480000]random seed for dissolve-family modes

mode Options（27）：

  • normal
  • dissolve
  • darken
  • multiply
  • color_burn
  • linear_burn
  • darker_color
  • lighten
  • screen
  • color_dodge
  • linear_dodge
  • lighter_color
  • overlay
  • soft_light
  • hard_light
  • vivid_light
  • linear_light
  • pin_light
  • hard_mix
  • difference
  • exclusion
  • subtract
  • divide
  • hue
  • saturation
  • color
  • luminosity

Example graph

A minimal runnable pipeline (read → process → write). Drag it into GraphStudio or open via --open; replace data/test.png with a real path.

{
  "version": "2.0",
  "tasks": [
    {
      "id": "read1",
      "type": "opencv_image_read",
      "params": {
        "file_path": "data/test.png"
      }
    },
    {
      "id": "read2",
      "type": "opencv_image_read",
      "params": {
        "file_path": "data/test.png"
      }
    },
    {
      "id": "node",
      "type": "blend",
      "params": {
        "mode": 0,
        "opacity": 1,
        "device": 0,
        "seed": 42
      }
    },
    {
      "id": "save",
      "type": "opencv_image_write",
      "params": {
        "file_path": "out_out.png"
      }
    }
  ],
  "edges": [
    {
      "from": "read1",
      "from_port": "out",
      "to": "node",
      "to_port": "in"
    },
    {
      "from": "read2",
      "from_port": "out",
      "to": "node",
      "to_port": "in2"
    },
    {
      "from": "node",
      "from_port": "out",
      "to": "save",
      "to_port": "in"
    }
  ]
}

Notes

  • Inputs must match in size; alpha handling follows the mode’s semantics when channel counts differ.
  • The HSL family (hue/saturation/color/luminosity) follows Photoshop transfer functions.

Part of the GraphStudio node guide series; parameters reflect the latest release.