Skill: camscanner-ai/camscanner-extract-formula (version 1.0.1)

--- name: camscanner-extract-formula description: Use CamScanner to extract formulas from images. Powered by OCR recognition engine that detects formula regions in images, crops them, and stitches into a single clean PNG image. Use when the user wants to extract mathematical formulas, equations, or expressions from images (photos, screenshots, scanned documents). Triggers on "extract formula", "get formulas from image", "crop formulas", "formula extraction", or when the user has an image containing math formulas and needs them extracted as a clean image. metadata: author: CamScanner version: "1.0" openclaw: emoji: "🔢" requires: bins: ["curl", "jq"] homepage: "https://www.camscanner.com" --- # CamScanner Extract Formula ## Overview CamScanner provides formula extraction from images: OCR recognition detects formula regions, crops them, and vertically stitches all formulas into a single clean PNG image. The workflow is a 3-step pipeline: **upload** the image, **extract** formulas, then **download** the result. ## When to Use - User wants to extract mathematical formulas or equations from an image - User has a photo, screenshot, or scanned document containing formulas - User needs formulas cropped out as a clean image for further use - User wants to isolate math content from surrounding text in an image ## Privacy & Data > **Important: Privacy & Data Flow Notice** > > - **Third-party service**: This skill sends your files to CamScanner's official servers (`ai-tools.camscanner.com`) for processing. > - **Data retention**: CamScanner servers process your files in real-time. Files are not permanently stored on the server. > - **Local files**: Output files are saved to your local filesystem at the path you specify. ## API Reference **Base URL:** `https://ai-tools.camscanner.com` ### Supported Modes | extract_mode | Description | Output | | ------------ | ---------------------------------------------------- | ------ | | formula | Extract math formulas, crop and stitch into one image | .png | ### Step 1: Upload Image ```bash BASE="https://ai-tools.camscanner.com" IN_FILE_ID=$(curl -sS -X POST "$BASE/v1/tools/upload_file/execute" \ -H "Content-Type: application/octet-stream" \ --data-binary "@/path/to/image.png" | jq -r '.tool_result.data.file_id') ``` **Response:** ```json { "code": 200, "tool": "upload_file", "tool_result": { "success": true, "data": { "file_id": "file_1741857600_ab12cd34ef56", "size": 24576 } } } ``` ### Step 2: Extract Formulas ```bash OUT_FILE_ID=$(curl -sS -X POST "$BASE/v1/tools/extract_image/execute" \ -H "Content-Type: application/json" \ -d "{\"file_id\":\"$IN_FILE_ID\",\"extract_mode\":\"formula\"}" \ | jq -r '.tool_result.data.file_id') ``` **Response:** ```json { "code": 200, "tool": "extract_image", "tool_result": { "success": true, "data": { "file_id": "file_1741857701_9988aabbccdd", "target_type": "" }, "metadata": { "engine": "extractformula", "formula_count": 6 } } } ``` ### Step 3: Download Result ```bash curl -sS -X POST "$BASE/v1/tools/download_file/execute?response_mode=raw" \ -H "Content-Type: application/json" \ -d "{\"file_id\":\"$OUT_FILE_ID\"}" \ -o /path/to/formulas.png ``` **Critical:** The `response_mode=raw` query parameter is required to get the binary file. Without it, the response is JSON. ## Quick Reference: Complete Pipeline ```bash BASE="https://ai-tools.camscanner.com" INPUT_IMAGE="/path/to/image.png" OUTPUT_FILE="/path/to/formulas.png" # Upload IN_FILE_ID=$(curl -sS -X POST "$BASE/v1/tools/upload_file/execute" \ -H "Content-Type: application/octet-stream" \ --data-binary "@$INPUT_IMAGE" | jq -r '.tool_result.data.file_id') # Extract OUT_FILE_ID=$(curl -sS -X POST "$BASE/v1/tools/extract_image/execute" \ -H "Content-Type: application/json" \ -d "{\"file_id\":\"$IN_FILE_ID\",\"extract_mode\":\"formula\"}" \ | jq -r '.tool_result.data.file_id') # Download curl -sS -X POST "$BASE/v1/tools/download_file/execute?response_mode=raw" \ -H "Content-Type: application/json" \ -d "{\"file_id\":\"$OUT_FILE_ID\"}" \ -o "$OUTPUT_FILE" ``` ## Common Mistakes | Mistake | Fix | | ------------------------------------------ | ----------------------------------------------------------------------- | | Forgetting `response_mode=raw` on download | Always append `?response_mode=raw` to the download URL | | Wrong Content-Type on upload | Upload uses `application/octet-stream`, not `multipart/form-data` | | Using GET instead of POST | All three endpoints use POST | | Missing `extract_mode` in extract request | Always include `"extract_mode": "formula"` | | Saving output with wrong extension | Output is always PNG format — use `.png` extension | ## Error Handling Check each step before proceeding: ```bash # After upload if [ -z "$IN_FILE_ID" ] || [ "$IN_FILE_ID" = "null" ]; then echo "Upload failed"; exit 1 fi # After extract if [ -z "$OUT_FILE_ID" ] || [ "$OUT_FILE_ID" = "null" ]; then echo "Extraction failed"; exit 1 fi ```


Security scan verdicts — ClawScan: clean | static analysis: clean | VirusTotal: clean | SkillSpector: clean (LOW)