More detailed result reporting for barcode plausibility checks

This will allow us to avoid redoing those checks several times, which can
be a problem for PDF content, as we use different sizes (source data,
output) depending on what information is available at any given point.

autotests/barcodedecodertest.cpp

@@ -99,14 +99,14 @@ private Q_SLOTS:
 
     void testPlausibilityCheck()
     {
-        QVERIFY(!BarcodeDecoder::maybeBarcode(10, 10, BarcodeDecoder::Any));
-        QVERIFY(BarcodeDecoder::maybeBarcode(100, 100, BarcodeDecoder::Any));
-        QVERIFY(!BarcodeDecoder::maybeBarcode(100, 100, BarcodeDecoder::PDF417));
-        QVERIFY(BarcodeDecoder::maybeBarcode(100, 100, BarcodeDecoder::Aztec));
-        QVERIFY(BarcodeDecoder::maybeBarcode(100, 100, BarcodeDecoder::AnySquare));
-        QVERIFY(BarcodeDecoder::maybeBarcode(100, 180, BarcodeDecoder::PDF417));
-        QVERIFY(BarcodeDecoder::maybeBarcode(180, 100, BarcodeDecoder::PDF417));
-        QVERIFY(!BarcodeDecoder::maybeBarcode(180, 100, BarcodeDecoder::AnySquare));
+        QCOMPARE(BarcodeDecoder::maybeBarcode(10, 10, BarcodeDecoder::Any), BarcodeDecoder::None);
+        QCOMPARE(BarcodeDecoder::maybeBarcode(100, 100, BarcodeDecoder::Any), BarcodeDecoder::AnySquare);
+        QCOMPARE(BarcodeDecoder::maybeBarcode(100, 100, BarcodeDecoder::PDF417), BarcodeDecoder::None);
+        QCOMPARE(BarcodeDecoder::maybeBarcode(100, 100, BarcodeDecoder::Aztec), BarcodeDecoder::Aztec);
+        QCOMPARE(BarcodeDecoder::maybeBarcode(100, 100, BarcodeDecoder::AnySquare), BarcodeDecoder::AnySquare);
+        QCOMPARE(BarcodeDecoder::maybeBarcode(100, 180, BarcodeDecoder::PDF417), BarcodeDecoder::PDF417);
+        QCOMPARE(BarcodeDecoder::maybeBarcode(180, 100, BarcodeDecoder::PDF417), BarcodeDecoder::PDF417);
+        QCOMPARE(BarcodeDecoder::maybeBarcode(180, 100, BarcodeDecoder::AnySquare), BarcodeDecoder::None);
     }
 
     void testNoCode()

src/lib/barcodedecoder.cpp

@@ -47,7 +47,7 @@ BarcodeDecoder::~BarcodeDecoder() = default;
 
 bool BarcodeDecoder::isBarcode(const QImage &img, BarcodeDecoder::BarcodeTypes hint) const
 {
-    if (!maybeBarcode(img.width(), img.height(), hint)) {
+    if (maybeBarcode(img.width(), img.height(), hint) == None) {
         return false;
     }
 
@@ -58,7 +58,7 @@ bool BarcodeDecoder::isBarcode(const QImage &img, BarcodeDecoder::BarcodeTypes h
 
 QByteArray BarcodeDecoder::decodeBinary(const QImage &img, BarcodeDecoder::BarcodeTypes hint) const
 {
-    if (!maybeBarcode(img.width(), img.height(), hint)) {
+    if (maybeBarcode(img.width(), img.height(), hint) == None) {
         return {};
     }
 
@@ -73,7 +73,7 @@ QByteArray BarcodeDecoder::decodeBinary(const QImage &img, BarcodeDecoder::Barco
 
 QString BarcodeDecoder::decodeString(const QImage &img, BarcodeDecoder::BarcodeTypes hint) const
 {
-    if (!maybeBarcode(img.width(), img.height(), hint)) {
+    if (maybeBarcode(img.width(), img.height(), hint) == None) {
         return {};
     }
 
@@ -91,21 +91,24 @@ void BarcodeDecoder::clearCache()
     m_cache.clear();
 }
 
-bool BarcodeDecoder::isPlausibleSize(int width, int height, BarcodeDecoder::BarcodeTypes hint)
+BarcodeDecoder::BarcodeTypes BarcodeDecoder::isPlausibleSize(int width, int height, BarcodeDecoder::BarcodeTypes hint)
 {
     // normalize to landscape
     if (height > width) {
         std::swap(width, height);
     }
 
-    return width > MinSourceImageWidth && height > MinSourceImageHeight
-        && ((width < MaxSourceImageWidth && height < MaxSourceImageHeight) || (hint & IgnoreAspectRatio));
+    if (width > MinSourceImageWidth && height > MinSourceImageHeight
+        && ((width < MaxSourceImageWidth && height < MaxSourceImageHeight) || (hint & IgnoreAspectRatio))) {
+        return hint;
+    }
+    return None;
 }
 
-bool BarcodeDecoder::isPlausibleAspectRatio(int width, int height, BarcodeDecoder::BarcodeTypes hint)
+BarcodeDecoder::BarcodeTypes BarcodeDecoder::isPlausibleAspectRatio(int width, int height, BarcodeDecoder::BarcodeTypes hint)
 {
     if (hint & IgnoreAspectRatio) {
-        return true;
+        return hint;
     }
 
     // normalize to landscape
@@ -116,26 +119,26 @@ bool BarcodeDecoder::isPlausibleAspectRatio(int width, int height, BarcodeDecode
     const auto aspectRatio = (float)width / (float)height;
 
     // almost square, assume Aztec or QR
-    if (aspectRatio < SQUARE_MAX_ASPECT && (hint & AnySquare)) {
-        return true;
+    if (aspectRatio > SQUARE_MAX_ASPECT) {
+        hint &= ~AnySquare;
     }
 
     // rectangular with medium aspect ratio, such as PDF 417
-    if (aspectRatio > PDF417_MIN_ASPECT && aspectRatio < PDF417_MAX_ASPECT && (hint & PDF417)) {
-        return true;
+    if (aspectRatio < PDF417_MIN_ASPECT || aspectRatio > PDF417_MAX_ASPECT) {
+        hint &= ~PDF417;
     }
 
     // 1D
-    if (aspectRatio > ANY1D_MIN_ASPECT && (hint & Any1D)) {
-        return true;
+    if (aspectRatio < ANY1D_MIN_ASPECT) {
+        hint &= ~Any1D;
     }
 
-    return false;
+    return hint;
 }
 
-bool BarcodeDecoder::maybeBarcode(int width, int height, BarcodeDecoder::BarcodeTypes hint)
+BarcodeDecoder::BarcodeTypes BarcodeDecoder::maybeBarcode(int width, int height, BarcodeDecoder::BarcodeTypes hint)
 {
-    return isPlausibleSize(width, height, hint) && isPlausibleAspectRatio(width, height, hint);
+    return isPlausibleSize(width, height, hint) & isPlausibleAspectRatio(width, height, hint);
 }
 
 #if HAVE_ZXING

src/lib/barcodedecoder.h

@@ -67,15 +67,15 @@ public:
      *  to perform them manually if a cheaper way to obtain the image dimension exists
      *  that does not require a full QImage creation.
      */
-    static bool isPlausibleSize(int width, int height, BarcodeTypes hint);
+    static BarcodeTypes isPlausibleSize(int width, int height, BarcodeTypes hint);
 
     /** Checks if the given image dimensions are a barcode of type @p hint.
      *  See above.
      */
-    static bool isPlausibleAspectRatio(int width, int height, BarcodeTypes hint);
+    static BarcodeTypes isPlausibleAspectRatio(int width, int height, BarcodeTypes hint);
 
     /** The combination of the above. */
-    static bool maybeBarcode(int width, int height, BarcodeTypes hint);
+    static BarcodeTypes maybeBarcode(int width, int height, BarcodeTypes hint);
 
 private:
     struct Result {

src/lib/jsapi/barcode.cpp

@@ -39,7 +39,7 @@ QJSValue JsApi::Barcode::decodeAztecBinary(const QVariant &img) const
 {
     if (img.userType() == qMetaTypeId<PdfImage>()) {
         const auto pdfImg = img.value<PdfImage>();
-        if (!PdfBarcodeUtil::maybeBarcode(pdfImg, BarcodeDecoder::Aztec)) {
+        if (PdfBarcodeUtil::maybeBarcode(pdfImg, BarcodeDecoder::Aztec) == BarcodeDecoder::None) {
             return {};
         }
         const auto content = m_decoder->decodeBinary(pdfImg.image(), BarcodeDecoder::Aztec);
@@ -79,7 +79,7 @@ QString JsApi::Barcode::decodeBarcode(const QVariant &img, BarcodeDecoder::Barco
 {
     if (img.userType() == qMetaTypeId<PdfImage>()) {
         const auto pdfImg = img.value<PdfImage>();
-        if (!PdfBarcodeUtil::maybeBarcode(pdfImg, hints)) {
+        if (PdfBarcodeUtil::maybeBarcode(pdfImg, hints) == BarcodeDecoder::None) {
             return {};
         }
         return m_decoder->decodeString(pdfImg.image(), hints);

src/lib/pdf/pdfbarcodeutil.cpp

@@ -14,22 +14,24 @@ enum {
     MinTargetImageHeight = 28,
     MinTargetImageWidth = 36,
     MaxTargetImageHeight = 252,
-    MaxTargetImageWidth = 252,
+    MaxTargetImageWidth2D = 252,
 };
 
-bool PdfBarcodeUtil::maybeBarcode(const PdfImage &img, BarcodeDecoder::BarcodeTypes hint)
+BarcodeDecoder::BarcodeTypes PdfBarcodeUtil::maybeBarcode(const PdfImage &img, BarcodeDecoder::BarcodeTypes hint)
 {
     const auto w = img.width();
     const auto h = img.height();
 
-    if (!BarcodeDecoder::isPlausibleSize(img.sourceWidth(), img.sourceHeight(), hint) || !BarcodeDecoder::isPlausibleAspectRatio(w, h, hint)) {
-        return false;
+    // image target size checks
+    if (std::min(w, h) < MinTargetImageHeight || std::max(w, h) < MinTargetImageWidth || std::min(w, h) > MaxTargetImageHeight) {
+        return BarcodeDecoder::None;
     }
 
-    // image target size checks
-    if (std::min(w, h) < MinTargetImageHeight || std::max(w, h) < MinTargetImageWidth || h > MaxTargetImageHeight || w > MaxTargetImageWidth) {
-        return false;
+    if (std::max(w, h) > MaxTargetImageWidth2D) {
+        hint &= ~BarcodeDecoder::Any2D;
     }
 
-    return true;
+    hint = BarcodeDecoder::isPlausibleSize(img.sourceWidth(), img.sourceHeight(), hint);
+    hint = BarcodeDecoder::isPlausibleAspectRatio(w, h, hint);
+    return hint;
 }

src/lib/pdf/pdfbarcodeutil_p.h

@@ -16,7 +16,7 @@ class PdfImage;
 namespace PdfBarcodeUtil
 {
     /** Quick pre-check without image decoding if @p img might be a barcode. */
-    bool maybeBarcode(const PdfImage &img, BarcodeDecoder::BarcodeTypes hint = BarcodeDecoder::Any2D);
+    BarcodeDecoder::BarcodeTypes maybeBarcode(const PdfImage &img, BarcodeDecoder::BarcodeTypes hint = BarcodeDecoder::Any2D);
 }
 
 }

src/lib/processors/imagedocumentprocessor.cpp

@@ -31,9 +31,10 @@ void ImageDocumentProcessor::expandNode(ExtractorDocumentNode &node, const Extra
     // check whether we possibly have a full PDF page raster image here
     const auto img = node.content<QImage>();
     BarcodeDecoder::BarcodeTypes barcodeHints = BarcodeDecoder::Any2D;
-    if (engine->hints() & ExtractorEngine::ExtractFullPageRasterImages && !BarcodeDecoder::maybeBarcode(img.width(), img.height(), barcodeHints)) {
+    if (engine->hints() & ExtractorEngine::ExtractFullPageRasterImages) {
         barcodeHints |= BarcodeDecoder::IgnoreAspectRatio;
     }
+    barcodeHints = BarcodeDecoder::maybeBarcode(img.width(), img.height(), barcodeHints);
 
     // in case the barcode raw data (string or bytearray) gets detected as a type we handle,
     // we nevertheless inject a raw data node in between. This is useful in cases where the

src/lib/processors/pdfdocumentprocessor.cpp

@@ -90,7 +90,7 @@ void PdfDocumentProcessor::expandNode(ExtractorDocumentNode &node, const Extract
                 continue;
             }
 
-            if (!PdfBarcodeUtil::maybeBarcode(img)) {
+            if (PdfBarcodeUtil::maybeBarcode(img, BarcodeDecoder::Any2D) == BarcodeDecoder::None) {
                 continue;
             }