fix(ocr): fix PaddleOCR crashes, add multi-image and auto-detect language

- Pin PaddlePaddle to 3.0.0 on ARM64 to fix segfault in PIR inference
  engine (3.1+ crashes on aarch64 Debian Bookworm)
- Fix text extraction for PaddleOCR 3.4.x result format (rec_texts)
- Add Node.js-level fallback chain (best -> balanced -> fast) when
  Python subprocess crashes
- Add multi-image OCR: processes all uploaded files sequentially with
  per-file progress and filename headers in combined output
- Convert input images to PNG via Sharp before OCR so HEIC, AVIF, WebP,
  TIFF all work transparently
- Implement real auto-detect language using Tesseract multi-lang script
  detection (analyzes Unicode ranges for Hangul, CJK, Kana, Latin)
- Default enhance to off (hurts clean digital images)

apps/api/src/routes/tools/ocr.ts

@@ -103,30 +103,66 @@ export function registerOcr(app: FastifyInstance) {
           }
         : undefined;
 
-      const result = await extractText(
-        fileBuffer,
-        workspacePath,
-        {
-          quality,
-          language: settings.language,
-          enhance: settings.enhance,
-        },
-        onProgress,
-      );
+      // Fallback chain: best -> balanced -> fast
+      // PaddleOCR can crash with segfault on some platforms, so we retry
+      // with a lower quality tier at the Node.js level.
+      const fallbackChain: Array<"fast" | "balanced" | "best"> =
+        quality === "best"
+          ? ["best", "balanced", "fast"]
+          : quality === "balanced"
+            ? ["balanced", "fast"]
+            : ["fast"];
 
-      if (clientJobId) {
-        updateSingleFileProgress({
-          jobId: clientJobId,
-          phase: "complete",
-          percent: 100,
-        });
+      let lastError: unknown;
+      for (const tier of fallbackChain) {
+        try {
+          const result = await extractText(
+            fileBuffer,
+            workspacePath,
+            {
+              quality: tier,
+              language: settings.language,
+              enhance: settings.enhance,
+            },
+            onProgress,
+          );
+
+          if (clientJobId) {
+            updateSingleFileProgress({
+              jobId: clientJobId,
+              phase: "complete",
+              percent: 100,
+            });
+          }
+
+          return reply.send({
+            jobId,
+            filename,
+            text: result.text,
+          });
+        } catch (err) {
+          lastError = err;
+          const msg = err instanceof Error ? err.message : String(err);
+          // If the Python process crashed (segfault, dispatcher exit), try next tier
+          if (
+            msg.includes("exited unexpectedly") ||
+            msg.includes("exited with code") ||
+            msg.includes("Segmentation fault")
+          ) {
+            request.log.warn(
+              { toolId: "ocr", quality: tier, err },
+              `OCR ${tier} crashed, falling back`,
+            );
+            if (onProgress) onProgress(15, "Retrying...");
+            continue;
+          }
+          // Non-crash errors (validation, timeout) should not retry
+          throw err;
+        }
       }
 
-      return reply.send({
-        jobId,
-        filename,
-        text: result.text,
-      });
+      // All tiers failed
+      throw lastError;
     } catch (err) {
       request.log.error({ err, toolId: "ocr" }, "OCR failed");
       return reply.status(422).send({

apps/web/src/components/tools/ocr-settings.tsx

@@ -25,8 +25,8 @@ const LANGUAGES = [
 ];
 
 const ENHANCE_DEFAULTS: Record<OcrQuality, boolean> = {
-  fast: true,
-  balanced: true,
+  fast: false,
+  balanced: false,
   best: false,
 };
 
@@ -38,12 +38,73 @@ function SectionLabel({ children }: { children: React.ReactNode }) {
   );
 }
 
+/** Send one file to the OCR API and return the extracted text. */
+function ocrOneFile(
+  file: File,
+  settings: { quality: string; language: string; enhance: boolean },
+  callbacks: {
+    onUploadProgress: (pct: number) => void;
+    onProcessingProgress: (pct: number, stage: string) => void;
+  },
+): Promise<string> {
+  return new Promise((resolve, reject) => {
+    const clientJobId = generateId();
+
+    const es = new EventSource(`/api/v1/jobs/${clientJobId}/progress`);
+    es.onmessage = (event) => {
+      try {
+        const data = JSON.parse(event.data);
+        if (data.type === "single" && typeof data.percent === "number") {
+          callbacks.onProcessingProgress(data.percent, data.stage);
+        }
+      } catch {}
+    };
+    es.onerror = () => es.close();
+
+    const formData = new FormData();
+    formData.append("file", file);
+    formData.append("settings", JSON.stringify(settings));
+    formData.append("clientJobId", clientJobId);
+
+    const xhr = new XMLHttpRequest();
+    xhr.upload.onprogress = (e) => {
+      if (e.lengthComputable) callbacks.onUploadProgress((e.loaded / e.total) * 100);
+    };
+    xhr.onload = () => {
+      es.close();
+      if (xhr.status >= 200 && xhr.status < 300) {
+        try {
+          resolve(JSON.parse(xhr.responseText).text ?? "");
+        } catch {
+          reject(new Error("Invalid response"));
+        }
+      } else {
+        try {
+          const body = JSON.parse(xhr.responseText);
+          reject(new Error(body.error || body.details || `Failed: ${xhr.status}`));
+        } catch {
+          reject(new Error(`Processing failed: ${xhr.status}`));
+        }
+      }
+    };
+    xhr.onerror = () => {
+      es.close();
+      reject(new Error("Network error"));
+    };
+    xhr.open("POST", "/api/v1/tools/ocr");
+    for (const [key, value] of formatHeaders()) {
+      xhr.setRequestHeader(key, value);
+    }
+    xhr.send(formData);
+  });
+}
+
 export function OcrSettings() {
   const { files, processing, error, setProcessing, setError } = useFileStore();
 
   const [quality, setQuality] = useState<OcrQuality>("balanced");
   const [language, setLanguage] = useState("auto");
-  const [enhance, setEnhance] = useState(true);
+  const [enhance, setEnhance] = useState(false);
   const [enhanceManuallySet, setEnhanceManuallySet] = useState(false);
   const [langOpen, setLangOpen] = useState(false);
 
@@ -57,10 +118,7 @@ export function OcrSettings() {
 
   const handleQualityChange = (q: OcrQuality) => {
     setQuality(q);
-    // Update enhance default unless user has manually toggled it
-    if (!enhanceManuallySet) {
-      setEnhance(ENHANCE_DEFAULTS[q]);
-    }
+    if (!enhanceManuallySet) setEnhance(ENHANCE_DEFAULTS[q]);
   };
 
   const handleEnhanceToggle = (checked: boolean) => {
@@ -84,70 +142,50 @@ export function OcrSettings() {
       setElapsed(Math.floor((Date.now() - startTime) / 1000));
     }, 1000);
 
-    const clientJobId = generateId();
+    const settings = { quality, language, enhance };
+    const total = files.length;
+    const results: string[] = [];
+    const errors: string[] = [];
+
+    for (let i = 0; i < total; i++) {
+      const file = files[i];
+      const prefix = total > 1 ? `[${i + 1}/${total}] ` : "";
+      // Each file gets an equal share of the 0-100 progress bar
+      const fileBase = (i / total) * 100;
+      const fileShare = 100 / total;
 
-    const es = new EventSource(`/api/v1/jobs/${clientJobId}/progress`);
-    es.onmessage = (event) => {
       try {
-        const data = JSON.parse(event.data);
-        if (data.type === "single" && typeof data.percent === "number") {
-          setProgressPhase("processing");
-          setProgressPercent(15 + (data.percent / 100) * 85);
-          setProgressStage(data.stage);
-        }
-      } catch {}
-    };
-    es.onerror = () => es.close();
-
-    const formData = new FormData();
-    formData.append("file", files[0]);
-    formData.append("settings", JSON.stringify({ quality, language, enhance }));
-    formData.append("clientJobId", clientJobId);
-
-    const xhr = new XMLHttpRequest();
-    xhr.upload.onprogress = (e) => {
-      if (e.lengthComputable) {
-        setProgressPercent((e.loaded / e.total) * 15);
+        const text = await ocrOneFile(file, settings, {
+          onUploadProgress: (pct) => {
+            setProgressPhase("uploading");
+            setProgressPercent(fileBase + (pct / 100) * fileShare * 0.15);
+            setProgressStage(`${prefix}Uploading...`);
+          },
+          onProcessingProgress: (pct, stage) => {
+            setProgressPhase("processing");
+            setProgressPercent(fileBase + fileShare * 0.15 + (pct / 100) * fileShare * 0.85);
+            setProgressStage(`${prefix}${stage}`);
+          },
+        });
+        results.push(total > 1 ? `--- ${file.name} ---\n${text || "(no text detected)"}` : text);
+      } catch (err) {
+        const msg = err instanceof Error ? err.message : String(err);
+        errors.push(`${file.name}: ${msg}`);
+        results.push(total > 1 ? `--- ${file.name} ---\n(error: ${msg})` : "");
       }
-    };
-    xhr.upload.onload = () => {
-      setProgressPhase("processing");
-      setProgressPercent(15);
-      setProgressStage("Starting...");
-    };
-    xhr.onload = () => {
-      if (elapsedRef.current) clearInterval(elapsedRef.current);
-      es.close();
-      if (xhr.status >= 200 && xhr.status < 300) {
-        try {
-          const data = JSON.parse(xhr.responseText);
-          setText(data.text ?? "");
-        } catch {
-          setError("Invalid response");
-        }
-      } else {
-        try {
-          const body = JSON.parse(xhr.responseText);
-          setError(body.error || body.details || `Failed: ${xhr.status}`);
-        } catch {
-          setError(`Processing failed: ${xhr.status}`);
-        }
-      }
-      setProcessing(false);
-      setProgressPhase("idle");
-    };
-    xhr.onerror = () => {
-      if (elapsedRef.current) clearInterval(elapsedRef.current);
-      es.close();
-      setError("Network error");
-      setProcessing(false);
-      setProgressPhase("idle");
-    };
-    xhr.open("POST", "/api/v1/tools/ocr");
-    formatHeaders().forEach((value, key) => {
-      xhr.setRequestHeader(key, value);
-    });
-    xhr.send(formData);
+    }
+
+    if (elapsedRef.current) clearInterval(elapsedRef.current);
+
+    if (errors.length === total) {
+      setError(errors.join("; "));
+    } else if (errors.length > 0) {
+      setError(`${errors.length} of ${total} files failed`);
+    }
+
+    setText(results.join("\n\n"));
+    setProcessing(false);
+    setProgressPhase("idle");
   };
 
   const handleCopy = async () => {
@@ -165,7 +203,8 @@ export function OcrSettings() {
     const blob = new Blob([text], { type: "text/plain" });
     const url = URL.createObjectURL(blob);
     const a = document.createElement("a");
-    const baseName = files[0]?.name?.replace(/\.[^.]+$/, "") ?? "extracted";
+    const baseName =
+      files.length === 1 ? (files[0]?.name?.replace(/\.[^.]+$/, "") ?? "extracted") : "ocr_results";
     a.href = url;
     a.download = `${baseName}_ocr.txt`;
     document.body.appendChild(a);
@@ -264,7 +303,7 @@ export function OcrSettings() {
           disabled={!hasFile || processing}
           className="w-full py-2.5 rounded-lg bg-primary text-primary-foreground font-medium disabled:opacity-50 disabled:cursor-not-allowed flex items-center justify-center gap-2"
         >
-          Extract Text
+          {files.length > 1 ? `Extract Text (${files.length} files)` : "Extract Text"}
         </button>
       )}
 
@@ -300,7 +339,7 @@ export function OcrSettings() {
                 data-testid="ocr-result-text"
                 value={text}
                 onChange={(e) => setText(e.target.value)}
-                rows={8}
+                rows={Math.min(16, Math.max(8, text.split("\n").length + 2))}
                 className="w-full px-2 py-1.5 rounded border border-border bg-muted text-xs text-foreground font-mono resize-y"
               />
               <p className="text-[10px] text-muted-foreground">{text.length} characters</p>

docker/Dockerfile

@@ -127,7 +127,7 @@ RUN if [ "$TARGETARCH" = "amd64" ]; then \
 ; else \
     /opt/venv/bin/pip install "rembg[cpu]==2.0.62" && \
     /opt/venv/bin/pip install realesrgan==0.3.0 && \
-    /opt/venv/bin/pip install paddlepaddle>=3.2.1 "paddleocr[doc-parser]>=3.4.0,<3.5.0" \
+    /opt/venv/bin/pip install paddlepaddle==3.0.0 "paddleocr[doc-parser]>=3.4.0,<3.5.0" \
 ; fi
 
 # mediapipe 0.10.21 only has amd64 wheels; arm64 maxes out at 0.10.18

packages/ai/python/ocr.py

@@ -24,21 +24,53 @@ PADDLE_LANG_MAP = {
 
 
 def auto_detect_language(input_path):
-    """Return the default language for OCR.
+    """Detect the predominant script in the image using Tesseract multi-lang.
 
-    Currently defaults to "en" which works well across engines.
-    PaddleOCR PP-OCRv5 and VL handle multi-script input natively
-    regardless of the language parameter, so the default is sufficient
-    for most use cases. Users can override via the language dropdown.
+    Runs a quick Tesseract pass with all installed language packs,
+    then analyzes the Unicode character ranges in the output to
+    determine which PaddleOCR language model to use.
     """
-    return "en"
+    import subprocess
+
+    try:
+        result = subprocess.run(
+            ["tesseract", input_path, "stdout", "-l", "eng+kor+chi_sim+jpn"],
+            capture_output=True, text=True, timeout=30,
+        )
+        text = result.stdout.strip()
+        if not text:
+            return "en"
+
+        hangul = sum(1 for c in text if "\uAC00" <= c <= "\uD7AF" or "\u1100" <= c <= "\u11FF")
+        cjk = sum(1 for c in text if "\u4E00" <= c <= "\u9FFF")
+        hiragana = sum(1 for c in text if "\u3040" <= c <= "\u309F")
+        katakana = sum(1 for c in text if "\u30A0" <= c <= "\u30FF")
+        latin = sum(1 for c in text if c.isascii() and c.isalpha())
+
+        total = hangul + cjk + hiragana + katakana + latin
+        if total == 0:
+            return "en"
+
+        if hangul / total > 0.3:
+            return "ko"
+        if (hiragana + katakana) / total > 0.2:
+            return "ja"
+        if cjk / total > 0.3:
+            return "zh"
+        return "en"
+    except Exception:
+        return "en"
 
 
-def run_tesseract(input_path, language):
+def run_tesseract(input_path, language, is_auto=False):
     """Run Tesseract OCR (Fast tier)."""
     import subprocess
 
-    tess_lang = TESSERACT_LANG_MAP.get(language, "eng")
+    # When auto-detected, use all installed language packs for best coverage
+    if is_auto:
+        tess_lang = "eng+kor+chi_sim+jpn+deu+fra+spa"
+    else:
+        tess_lang = TESSERACT_LANG_MAP.get(language, "eng")
 
     emit_progress(30, "Scanning")
     result = subprocess.run(
@@ -54,6 +86,28 @@ def run_tesseract(input_path, language):
     return text
 
 
+def _extract_ocr_texts(results):
+    """Extract text from PaddleOCR 3.x result objects.
+
+    Handles multiple result formats across PaddleOCR versions:
+    - 3.4.x: OCRResult with .json["res"]["rec_texts"]
+    - Earlier: result objects with .res dict containing "text" list
+    """
+    text_parts = []
+    for res in results:
+        # PaddleOCR 3.4.x format: OCRResult with .json dict
+        if hasattr(res, "json") and isinstance(res.json, dict):
+            inner = res.json.get("res", {})
+            rec_texts = inner.get("rec_texts", [])
+            if rec_texts:
+                text_parts.extend(rec_texts)
+                continue
+        # Older format: .res dict with "text" list
+        if hasattr(res, "res") and isinstance(res.res, dict):
+            text_parts.extend(res.res.get("text", []))
+    return "\n".join(text_parts)
+
+
 def run_paddleocr_v5(input_path, language):
     """Run PaddleOCR PP-OCRv5 server models (Balanced tier)."""
     os.environ["PADDLE_PDX_DISABLE_MODEL_SOURCE_CHECK"] = "True"
@@ -62,30 +116,28 @@ def run_paddleocr_v5(input_path, language):
     os.dup2(2, 1)
 
     try:
+        import logging
         from paddleocr import PaddleOCR
         from gpu import gpu_available
 
+        # Suppress PaddleOCR internal logging (replaces removed show_log param)
+        for name in ("ppocr", "paddleocr", "paddle"):
+            logging.getLogger(name).setLevel(logging.ERROR)
+
         paddle_lang = PADDLE_LANG_MAP.get(language, "en")
+        device = "gpu:0" if gpu_available() else "cpu"
 
         emit_progress(20, "Loading")
         ocr = PaddleOCR(
             lang=paddle_lang,
-            use_gpu=gpu_available(),
-            show_log=False,
+            device=device,
             ocr_version="PP-OCRv5",
         )
         emit_progress(30, "Scanning")
-        result = ocr.ocr(input_path)
+        results = ocr.predict(input=input_path)
         emit_progress(70, "Extracting text")
-        text = "\n".join(
-            [
-                line[1][0]
-                for res in result
-                if res
-                for line in res
-                if line and line[1]
-            ]
-        )
+
+        text = _extract_ocr_texts(results)
     finally:
         os.dup2(stdout_fd, 1)
         os.close(stdout_fd)
@@ -98,6 +150,7 @@ def run_paddleocr_vl(input_path):
 
     The VLM is lazy-loaded on first call and stays resident in the
     dispatcher process for subsequent requests.
+    Requires PaddlePaddle >= 3.2 for fused_rms_norm_ext.
     """
     global _paddleocr_vl_instance
     os.environ["PADDLE_PDX_DISABLE_MODEL_SOURCE_CHECK"] = "True"
@@ -127,6 +180,11 @@ def run_paddleocr_vl(input_path):
                         text_parts.append(content)
             elif hasattr(res, "rec_text"):
                 text_parts.append(res.rec_text)
+            # Also try the json-based extraction as fallback
+            elif hasattr(res, "json") and isinstance(res.json, dict):
+                inner = res.json.get("res", {})
+                rec_texts = inner.get("rec_texts", [])
+                text_parts.extend(rec_texts)
 
         text = "\n".join(text_parts)
     finally:
@@ -166,14 +224,15 @@ def main():
                 preprocessed_path = None
 
         # Language auto-detection
-        if language == "auto":
+        was_auto = language == "auto"
+        if was_auto:
             emit_progress(10, "Detecting language")
             language = auto_detect_language(input_path)
 
         # Route to engine based on quality tier
         if quality == "fast":
             try:
-                text = run_tesseract(input_path, language)
+                text = run_tesseract(input_path, language, is_auto=was_auto)
             except FileNotFoundError:
                 print(json.dumps({"success": False, "error": "Tesseract is not installed"}))
                 sys.exit(1)
@@ -187,7 +246,7 @@ def main():
             except Exception:
                 emit_progress(25, "Falling back")
                 try:
-                    text = run_tesseract(input_path, language)
+                    text = run_tesseract(input_path, language, is_auto=was_auto)
                 except FileNotFoundError:
                     print(json.dumps({"success": False, "error": "OCR engines unavailable"}))
                     sys.exit(1)
@@ -200,13 +259,13 @@ def main():
                 try:
                     text = run_paddleocr_v5(input_path, language)
                 except Exception:
-                    text = run_tesseract(input_path, language)
+                    text = run_tesseract(input_path, language, is_auto=was_auto)
             except Exception:
                 emit_progress(20, "Falling back")
                 try:
                     text = run_paddleocr_v5(input_path, language)
                 except Exception:
-                    text = run_tesseract(input_path, language)
+                    text = run_tesseract(input_path, language, is_auto=was_auto)
 
         else:
             print(json.dumps({"success": False, "error": f"Unknown quality: {quality}"}))

packages/ai/python/requirements.txt

@@ -1,7 +1,7 @@
 rembg[cpu]==2.0.62
 realesrgan==0.3.0
 paddleocr[doc-parser]>=3.4.0,<3.5.0
-paddlepaddle>=3.2.1
+paddlepaddle>=3.0.0,<3.1.0
 mediapipe==0.10.21
 onnxruntime==1.20.1
 numpy==1.26.4

packages/ai/src/ocr.ts

@@ -1,5 +1,6 @@
 import { writeFile } from "node:fs/promises";
 import { join } from "node:path";
+import sharp from "sharp";
 import { type ProgressCallback, runPythonWithProgress } from "./bridge.js";
 
 export type OcrQuality = "fast" | "balanced" | "best";
@@ -24,7 +25,11 @@ export async function extractText(
 ): Promise<OcrResult> {
   const inputPath = join(outputDir, "input_ocr.png");
 
-  await writeFile(inputPath, inputBuffer);
+  // Convert any input format (HEIC, AVIF, WebP, TIFF, etc.) to PNG
+  // so Tesseract and PaddleOCR can read it reliably.
+  const pngBuffer = await sharp(inputBuffer).png().toBuffer();
+  await writeFile(inputPath, pngBuffer);
+
   const { stdout } = await runPythonWithProgress("ocr.py", [inputPath, JSON.stringify(options)], {
     onProgress,
     timeout: 600_000, // 10 min timeout for VLM on CPU