{ "title": "Threshold image", "human_url": "https://happytails.ai/en/image-tools/threshold-image/", "agent_url": "https://happytails.ai/agents/en/image-tools/threshold-image/", "language": "en", "markdown_url": "https://happytails.ai/en/image-tools/threshold-image.md", "content": "Threshold image\nConvert an image to pure black and white.\nUseful next steps\nCircle crop image\nCrop a centered circle and download a transparent PNG.\nRound image corners\nGive an image rounded corners with a transparent background.\nAdd image border\nAdd a solid border without covering your image.\nHow to use Threshold image\nChoose a supported file using the drop area or file picker.\nReview the clearly labeled settings. The preview updates automatically.\nCompare the result with your original, then download it. Keep the original for further edits.\nWhat to expect\nConvert an image to pure black and white. Luminance threshold 0 to 255; preserve transparency; PNG output has only black or white RGB pixels.", "content_format": "text/plain", "visibility": "public", "links": [ { "name": "Circle crop image Crop a centered circle and download a transparent PNG.", "url": "https://happytails.ai/en/image-tools/circle-crop-image/" }, { "name": "Round image corners Give an image rounded corners with a transparent background.", "url": "https://happytails.ai/en/image-tools/round-image-corners/" }, { "name": "Add image border Add a solid border without covering your image.", "url": "https://happytails.ai/en/image-tools/add-image-border/" } ], "tool": { "id": "threshold-image", "category": "image-tools", "built": true, "requirements": "Luminance threshold 0 to 255; preserve transparency; PNG output has only black or white RGB pixels.", "implementation": { "fields": [ { "key": "threshold", "label": "Black / white threshold", "value": 128, "type": "number", "min": 0, "max": 255, "step": 1 } ], "files": true, "input": false, "live": true, "liveFiles": true, "accept": ".png,.jpg,.jpeg,.webp", "maxFileBytes": 20971520, "note": "Runs on your device. Select an image for an automatic preview; settings update the result. Animated WebP produces one still frame.", "experience": { "automatic": true, "single": false, "label": "Your text", "placeholder": "Type or paste your input…", "help": "Change the input or settings to update your result. Results update as you type. Up to 1,000,000 characters.", "action": null }, "mode": "automatic", "interactive": false }, "execution": "POST /api/v1/tools/threshold-image/run", "api": { "id": "threshold-image", "name": "Threshold image", "category": "image-tools", "description": "Convert an image to pure black and white.", "notes": "Runs on your device. Select an image for an automatic preview; settings update the result. Animated WebP produces one still frame.", "human_path": "/en/image-tools/threshold-image/", "method": "POST", "endpoint": "/api/v1/tools/threshold-image/run", "schema_url": "/api/v1/tools/threshold-image", "input_schema": { "type": "object", "additionalProperties": false, "properties": { "input": { "type": "string", "maxLength": 1000000, "default": "", "description": "Plain text input. File tools use files instead unless otherwise documented." }, "options": { "type": "object", "additionalProperties": false, "properties": { "threshold": { "type": "number", "description": "Black / white threshold", "default": 128.0, "minimum": 0, "maximum": 255, "multipleOf": 1 } } }, "files": { "type": "array", "maxItems": 1, "items": { "type": "object", "required": [ "name", "base64" ], "additionalProperties": false, "properties": { "name": { "type": "string", "maxLength": 200, "description": "Filename only, no path." }, "mime": { "type": "string", "maxLength": 150 }, "bytes": { "type": "integer", "minimum": 0, "description": "Optional decoded byte count; must match content if supplied." }, "base64": { "type": "string", "contentEncoding": "base64", "description": "File bytes as padded base64. Use the tool-specific limits.files_bytes value for the total decoded input size." } } } } } }, "output_schema": { "type": "object", "required": [ "tool", "result" ], "properties": { "tool": { "type": "string" }, "result": { "type": "object", "required": [ "text", "files" ], "properties": { "text": { "type": [ "string", "null" ] }, "data": { "description": "Parsed JSON when the textual result is JSON." }, "name": { "type": "string" }, "mime": { "type": "string" }, "files": { "type": "array", "items": { "type": "object", "required": [ "name", "mime", "bytes", "base64" ], "properties": { "name": { "type": "string" }, "mime": { "type": "string" }, "bytes": { "type": "integer" }, "base64": { "type": "string", "contentEncoding": "base64" } } } } } } } }, "processing": "Server; same transformation code as browser tools", "limits": { "request_bytes": 8388608, "input_characters": 1000000, "files_bytes": 5242880, "max_files": 1, "timeout_seconds": 12 } }, "agent_processing": "Server; same transformation code as browser tools", "browser_agent": { "supported": true, "name": "run_current_tool", "discovery": "WebMCP on the human page in a supporting browser", "verification": "See audit/API-AUDIT.md; availability is not verification" } }, "markdown": "# Threshold image\n\n- Human page: https://happytails.ai/en/image-tools/threshold-image/\n- Markdown: https://happytails.ai/en/image-tools/threshold-image.md\n- Structured JSON: https://happytails.ai/agents/en/image-tools/threshold-image/index.json\n- Visibility: public\n\n## Tool capabilities\n\n| Property | Value |\n| --- | --- |\n| Tool ID | `threshold-image` |\n| Category | image-tools |\n| Implementation | Registered implementation. Registration alone is not a production-quality guarantee. |\n| Browser execution | Automatic updates after valid input or file selection. |\n| Browser processing | Browser; see tool notes for network behavior. |\n| HTTP API | /api/v1/tools/threshold-image/run |\n| Browser-agent interface | run_current_tool |\n\n### Implementation notes\n\nRuns on your device. Select an image for an automatic preview; settings update the result. Animated WebP produces one still frame.\n\n### Inputs and settings\n\nNo free-text input is required. Use the file inputs and/or settings below.\n\nAccepted browser files: `.png,.jpg,.jpeg,.webp`. Choose one file.\n\nBrowser file-input limit: 20971520 bytes in total. HTTP limits can differ.\n\n| Setting | Meaning | Control type | Default | Constraints |\n| --- | --- | --- | --- | --- |\n| `threshold` | Black / white threshold | number | 128 | min=0 max=255 step=1 |\n\n### HTTP contract\n\nAPI calls process supplied data on the server. The website origin is `https://happytails.ai`. Server API hosting is not connected on the public website yet. Use your local server origin to test these requests.\n\n```http\nPOST https://happytails.ai/api/v1/tools/threshold-image/run\nContent-Type: application/json\n```\n\n[Detailed operation reference](https://happytails.ai/en/api/tools/threshold-image.md) · [Shared API guide](https://happytails.ai/en/api.md)\n\n#### Limits\n\n| Limit | Value |\n| --- | --- |\n| request_bytes | 8388608 |\n| input_characters | 1000000 |\n| files_bytes | 5242880 |\n| max_files | 1 |\n| timeout_seconds | 12 |\n\n#### Complete input schema\n\n```json\n{\n \"type\": \"object\",\n \"additionalProperties\": false,\n \"properties\": {\n \"input\": {\n \"type\": \"string\",\n \"maxLength\": 1000000,\n \"default\": \"\",\n \"description\": \"Plain text input. File tools use files instead unless otherwise documented.\"\n },\n \"options\": {\n \"type\": \"object\",\n \"additionalProperties\": false,\n \"properties\": {\n \"threshold\": {\n \"type\": \"number\",\n \"description\": \"Black / white threshold\",\n \"default\": 128.0,\n \"minimum\": 0,\n \"maximum\": 255,\n \"multipleOf\": 1\n }\n }\n },\n \"files\": {\n \"type\": \"array\",\n \"maxItems\": 1,\n \"items\": {\n \"type\": \"object\",\n \"required\": [\n \"name\",\n \"base64\"\n ],\n \"additionalProperties\": false,\n \"properties\": {\n \"name\": {\n \"type\": \"string\",\n \"maxLength\": 200,\n \"description\": \"Filename only, no path.\"\n },\n \"mime\": {\n \"type\": \"string\",\n \"maxLength\": 150\n },\n \"bytes\": {\n \"type\": \"integer\",\n \"minimum\": 0,\n \"description\": \"Optional decoded byte count; must match content if supplied.\"\n },\n \"base64\": {\n \"type\": \"string\",\n \"contentEncoding\": \"base64\",\n \"description\": \"File bytes as padded base64. Use the tool-specific limits.files_bytes value for the total decoded input size.\"\n }\n }\n }\n }\n }\n}\n```\n\n#### Complete output schema\n\n```json\n{\n \"type\": \"object\",\n \"required\": [\n \"tool\",\n \"result\"\n ],\n \"properties\": {\n \"tool\": {\n \"type\": \"string\"\n },\n \"result\": {\n \"type\": \"object\",\n \"required\": [\n \"text\",\n \"files\"\n ],\n \"properties\": {\n \"text\": {\n \"type\": [\n \"string\",\n \"null\"\n ]\n },\n \"data\": {\n \"description\": \"Parsed JSON when the textual result is JSON.\"\n },\n \"name\": {\n \"type\": \"string\"\n },\n \"mime\": {\n \"type\": \"string\"\n },\n \"files\": {\n \"type\": \"array\",\n \"items\": {\n \"type\": \"object\",\n \"required\": [\n \"name\",\n \"mime\",\n \"bytes\",\n \"base64\"\n ],\n \"properties\": {\n \"name\": {\n \"type\": \"string\"\n },\n \"mime\": {\n \"type\": \"string\"\n },\n \"bytes\": {\n \"type\": \"integer\"\n },\n \"base64\": {\n \"type\": \"string\",\n \"contentEncoding\": \"base64\"\n }\n }\n }\n }\n }\n }\n }\n}\n```\n\n#### Error and retry handling\n\nFailures return a non-200 status and `error.code` plus `error.message`. Correct invalid input before retrying; retry server-busy responses with bounded backoff. Returned files contain Base64 data, not persistent download URLs. Decode and inspect the output before treating conversion as successful. See the shared API guide for the complete status and timeout rules.\n\n### Browser-agent workflow\n\n1. Open the human page in a browser that supports WebMCP.\n2. Discover the interface exposed by that page; use its actual schema.\n3. Select files on the page first when the tool requires files.\n4. Call `run_current_tool` with valid input and settings.\n5. Inspect the returned result or error and the displayed output. Retrieve files from the displayed download links.\n\nCalls do not automatically copy or download results. Browser permissions still apply. Interface availability alone is not proof of successful execution.\n\n### Planning specification\n\nLuminance threshold 0 to 255; preserve transparency; PNG output has only black or white RGB pixels.\n\nThis describes intended requirements. Use the implementation notes, interface schema and observed output to determine current support.\n\n### Complete machine-readable capability record\n\n```json\n{\n \"id\": \"threshold-image\",\n \"category\": \"image-tools\",\n \"built\": true,\n \"requirements\": \"Luminance threshold 0 to 255; preserve transparency; PNG output has only black or white RGB pixels.\",\n \"implementation\": {\n \"fields\": [\n {\n \"key\": \"threshold\",\n \"label\": \"Black / white threshold\",\n \"value\": 128,\n \"type\": \"number\",\n \"min\": 0,\n \"max\": 255,\n \"step\": 1\n }\n ],\n \"files\": true,\n \"input\": false,\n \"live\": true,\n \"liveFiles\": true,\n \"accept\": \".png,.jpg,.jpeg,.webp\",\n \"maxFileBytes\": 20971520,\n \"note\": \"Runs on your device. Select an image for an automatic preview; settings update the result. Animated WebP produces one still frame.\",\n \"experience\": {\n \"automatic\": true,\n \"single\": false,\n \"label\": \"Your text\",\n \"placeholder\": \"Type or paste your input…\",\n \"help\": \"Change the input or settings to update your result. Results update as you type. Up to 1,000,000 characters.\",\n \"action\": null\n },\n \"mode\": \"automatic\",\n \"interactive\": false\n },\n \"execution\": \"POST /api/v1/tools/threshold-image/run\",\n \"api\": {\n \"id\": \"threshold-image\",\n \"name\": \"Threshold image\",\n \"category\": \"image-tools\",\n \"description\": \"Convert an image to pure black and white.\",\n \"notes\": \"Runs on your device. Select an image for an automatic preview; settings update the result. Animated WebP produces one still frame.\",\n \"human_path\": \"/en/image-tools/threshold-image/\",\n \"method\": \"POST\",\n \"endpoint\": \"/api/v1/tools/threshold-image/run\",\n \"schema_url\": \"/api/v1/tools/threshold-image\",\n \"input_schema\": {\n \"type\": \"object\",\n \"additionalProperties\": false,\n \"properties\": {\n \"input\": {\n \"type\": \"string\",\n \"maxLength\": 1000000,\n \"default\": \"\",\n \"description\": \"Plain text input. File tools use files instead unless otherwise documented.\"\n },\n \"options\": {\n \"type\": \"object\",\n \"additionalProperties\": false,\n \"properties\": {\n \"threshold\": {\n \"type\": \"number\",\n \"description\": \"Black / white threshold\",\n \"default\": 128.0,\n \"minimum\": 0,\n \"maximum\": 255,\n \"multipleOf\": 1\n }\n }\n },\n \"files\": {\n \"type\": \"array\",\n \"maxItems\": 1,\n \"items\": {\n \"type\": \"object\",\n \"required\": [\n \"name\",\n \"base64\"\n ],\n \"additionalProperties\": false,\n \"properties\": {\n \"name\": {\n \"type\": \"string\",\n \"maxLength\": 200,\n \"description\": \"Filename only, no path.\"\n },\n \"mime\": {\n \"type\": \"string\",\n \"maxLength\": 150\n },\n \"bytes\": {\n \"type\": \"integer\",\n \"minimum\": 0,\n \"description\": \"Optional decoded byte count; must match content if supplied.\"\n },\n \"base64\": {\n \"type\": \"string\",\n \"contentEncoding\": \"base64\",\n \"description\": \"File bytes as padded base64. Use the tool-specific limits.files_bytes value for the total decoded input size.\"\n }\n }\n }\n }\n }\n },\n \"output_schema\": {\n \"type\": \"object\",\n \"required\": [\n \"tool\",\n \"result\"\n ],\n \"properties\": {\n \"tool\": {\n \"type\": \"string\"\n },\n \"result\": {\n \"type\": \"object\",\n \"required\": [\n \"text\",\n \"files\"\n ],\n \"properties\": {\n \"text\": {\n \"type\": [\n \"string\",\n \"null\"\n ]\n },\n \"data\": {\n \"description\": \"Parsed JSON when the textual result is JSON.\"\n },\n \"name\": {\n \"type\": \"string\"\n },\n \"mime\": {\n \"type\": \"string\"\n },\n \"files\": {\n \"type\": \"array\",\n \"items\": {\n \"type\": \"object\",\n \"required\": [\n \"name\",\n \"mime\",\n \"bytes\",\n \"base64\"\n ],\n \"properties\": {\n \"name\": {\n \"type\": \"string\"\n },\n \"mime\": {\n \"type\": \"string\"\n },\n \"bytes\": {\n \"type\": \"integer\"\n },\n \"base64\": {\n \"type\": \"string\",\n \"contentEncoding\": \"base64\"\n }\n }\n }\n }\n }\n }\n }\n },\n \"processing\": \"Server; same transformation code as browser tools\",\n \"limits\": {\n \"request_bytes\": 8388608,\n \"input_characters\": 1000000,\n \"files_bytes\": 5242880,\n \"max_files\": 1,\n \"timeout_seconds\": 12\n }\n },\n \"agent_processing\": \"Server; same transformation code as browser tools\",\n \"browser_agent\": {\n \"supported\": true,\n \"name\": \"run_current_tool\",\n \"discovery\": \"WebMCP on the human page in a supporting browser\",\n \"verification\": \"See audit/API-AUDIT.md; availability is not verification\"\n }\n}\n```\n\n## Page guide\n\nConvert an image to pure black and white.\n\n## Useful next steps\n\n- [Circle crop image](https://happytails.ai/en/image-tools/circle-crop-image/): Crop a centered circle and download a transparent PNG. ([Markdown](https://happytails.ai/en/image-tools/circle-crop-image.md))\n\n- [Round image corners](https://happytails.ai/en/image-tools/round-image-corners/): Give an image rounded corners with a transparent background. ([Markdown](https://happytails.ai/en/image-tools/round-image-corners.md))\n\n- [Add image border](https://happytails.ai/en/image-tools/add-image-border/): Add a solid border without covering your image. ([Markdown](https://happytails.ai/en/image-tools/add-image-border.md))\n\n## How to use Threshold image\n\n1. Choose a supported file using the drop area or file picker.\n2. Review the clearly labeled settings. The preview updates automatically.\n3. Compare the result with your original, then download it. Keep the original for further edits.\n\n## What to expect\n\nConvert an image to pure black and white. Luminance threshold 0 to 255; preserve transparency; PNG output has only black or white RGB pixels.\n" }