Merge 0f9f8d71d9 into 88d0d90471

Resolve conflicts:
- GfxRenderer: Add cropX/cropY params to drawBitmap, keep 1-bit BMP support
- GfxRenderer: Update drawBitmap1Bit to use readNextRow (API change)
- JpegToBmpConverter: Use upstream scaling logic (larger dimension)
- HomeActivity: Use StringUtils::checkFileExtension, add hasOpdsUrl
- HomeActivity: Keep cover image functionality with own buffer management

lib/Epub/Epub.cpp

@@ -403,6 +403,70 @@ bool Epub::generateCoverBmp() const {
   return false;
 }
 
+std::string Epub::getThumbBmpPath() const { return cachePath + "/thumb.bmp"; }
+
+bool Epub::generateThumbBmp() const {
+  // Already generated, return true
+  if (SdMan.exists(getThumbBmpPath().c_str())) {
+    return true;
+  }
+
+  if (!bookMetadataCache || !bookMetadataCache->isLoaded()) {
+    Serial.printf("[%lu] [EBP] Cannot generate thumb BMP, cache not loaded\n", millis());
+    return false;
+  }
+
+  const auto coverImageHref = bookMetadataCache->coreMetadata.coverItemHref;
+  if (coverImageHref.empty()) {
+    Serial.printf("[%lu] [EBP] No known cover image for thumbnail\n", millis());
+    return false;
+  }
+
+  if (coverImageHref.substr(coverImageHref.length() - 4) == ".jpg" ||
+      coverImageHref.substr(coverImageHref.length() - 5) == ".jpeg") {
+    Serial.printf("[%lu] [EBP] Generating thumb BMP from JPG cover image\n", millis());
+    const auto coverJpgTempPath = getCachePath() + "/.cover.jpg";
+
+    FsFile coverJpg;
+    if (!SdMan.openFileForWrite("EBP", coverJpgTempPath, coverJpg)) {
+      return false;
+    }
+    readItemContentsToStream(coverImageHref, coverJpg, 1024);
+    coverJpg.close();
+
+    if (!SdMan.openFileForRead("EBP", coverJpgTempPath, coverJpg)) {
+      return false;
+    }
+
+    FsFile thumbBmp;
+    if (!SdMan.openFileForWrite("EBP", getThumbBmpPath(), thumbBmp)) {
+      coverJpg.close();
+      return false;
+    }
+    // Use smaller target size for Continue Reading card (half of screen: 240x400)
+    // Generate 1-bit BMP for fast home screen rendering (no gray passes needed)
+    constexpr int THUMB_TARGET_WIDTH = 240;
+    constexpr int THUMB_TARGET_HEIGHT = 400;
+    const bool success = JpegToBmpConverter::jpegFileTo1BitBmpStreamWithSize(coverJpg, thumbBmp, THUMB_TARGET_WIDTH,
+                                                                             THUMB_TARGET_HEIGHT);
+    coverJpg.close();
+    thumbBmp.close();
+    SdMan.remove(coverJpgTempPath.c_str());
+
+    if (!success) {
+      Serial.printf("[%lu] [EBP] Failed to generate thumb BMP from JPG cover image\n", millis());
+      SdMan.remove(getThumbBmpPath().c_str());
+    }
+    Serial.printf("[%lu] [EBP] Generated thumb BMP from JPG cover image, success: %s\n", millis(),
+                  success ? "yes" : "no");
+    return success;
+  } else {
+    Serial.printf("[%lu] [EBP] Cover image is not a JPG, skipping thumbnail\n", millis());
+  }
+
+  return false;
+}
+
 uint8_t* Epub::readItemContentsToBytes(const std::string& itemHref, size_t* size, const bool trailingNullByte) const {
   if (itemHref.empty()) {
     Serial.printf("[%lu] [EBP] Failed to read item, empty href\n", millis());

lib/Epub/Epub.h

@@ -46,6 +46,8 @@ class Epub {
   const std::string& getAuthor() const;
   std::string getCoverBmpPath() const;
   bool generateCoverBmp() const;
+  std::string getThumbBmpPath() const;
+  bool generateThumbBmp() const;
   uint8_t* readItemContentsToBytes(const std::string& itemHref, size_t* size = nullptr,
                                    bool trailingNullByte = false) const;
   bool readItemContentsToStream(const std::string& itemHref, Print& out, size_t chunkSize) const;

lib/GfxRenderer/Bitmap.cpp

@@ -336,7 +336,10 @@ BmpReaderError Bitmap::readNextRow(uint8_t* data, uint8_t* rowBuffer) const {
     }
     case 1: {
       for (int x = 0; x < width; x++) {
-        lum = (rowBuffer[x >> 3] & (0x80 >> (x & 7))) ? 0xFF : 0x00;
+        // Get palette index (0 or 1) from bit at position x
+        const uint8_t palIndex = (rowBuffer[x >> 3] & (0x80 >> (x & 7))) ? 1 : 0;
+        // Use palette lookup for proper black/white mapping
+        lum = paletteLum[palIndex];
         packPixel(lum);
       }
       break;

lib/GfxRenderer/Bitmap.h

@@ -38,6 +38,8 @@ class Bitmap {
   bool isTopDown() const { return topDown; }
   bool hasGreyscale() const { return bpp > 1; }
   int getRowBytes() const { return rowBytes; }
+  bool is1Bit() const { return bpp == 1; }
+  uint16_t getBpp() const { return bpp; }
 
  private:
   static uint16_t readLE16(FsFile& f);

lib/GfxRenderer/GfxRenderer.cpp

@@ -154,6 +154,12 @@ void GfxRenderer::drawImage(const uint8_t bitmap[], const int x, const int y, co
 
 void GfxRenderer::drawBitmap(const Bitmap& bitmap, const int x, const int y, const int maxWidth, const int maxHeight,
                              const float cropX, const float cropY) const {
+  // For 1-bit bitmaps, use optimized 1-bit rendering path (no crop support for 1-bit)
+  if (bitmap.is1Bit() && cropX == 0.0f && cropY == 0.0f) {
+    drawBitmap1Bit(bitmap, x, y, maxWidth, maxHeight);
+    return;
+  }
+
   float scale = 1.0f;
   bool isScaled = false;
   int cropPixX = std::floor(bitmap.getWidth() * cropX / 2.0f);
@@ -195,6 +201,9 @@ void GfxRenderer::drawBitmap(const Bitmap& bitmap, const int x, const int y, con
     if (screenY >= getScreenHeight()) {
       break;
     }
+    if (screenY < 0) {
+      continue;
+    }
 
     if (bitmap.readNextRow(outputRow, rowBytes) != BmpReaderError::Ok) {
       Serial.printf("[%lu] [GFX] Failed to read row %d from bitmap\n", millis(), bmpY);
@@ -217,6 +226,9 @@ void GfxRenderer::drawBitmap(const Bitmap& bitmap, const int x, const int y, con
       if (screenX >= getScreenWidth()) {
         break;
       }
+      if (screenX < 0) {
+        continue;
+      }
 
       const uint8_t val = outputRow[bmpX / 4] >> (6 - ((bmpX * 2) % 8)) & 0x3;
 
@@ -234,6 +246,143 @@ void GfxRenderer::drawBitmap(const Bitmap& bitmap, const int x, const int y, con
   free(rowBytes);
 }
 
+void GfxRenderer::drawBitmap1Bit(const Bitmap& bitmap, const int x, const int y, const int maxWidth,
+                                 const int maxHeight) const {
+  float scale = 1.0f;
+  bool isScaled = false;
+  if (maxWidth > 0 && bitmap.getWidth() > maxWidth) {
+    scale = static_cast<float>(maxWidth) / static_cast<float>(bitmap.getWidth());
+    isScaled = true;
+  }
+  if (maxHeight > 0 && bitmap.getHeight() > maxHeight) {
+    scale = std::min(scale, static_cast<float>(maxHeight) / static_cast<float>(bitmap.getHeight()));
+    isScaled = true;
+  }
+
+  // For 1-bit BMP, output is still 2-bit packed (for consistency with readNextRow)
+  const int outputRowSize = (bitmap.getWidth() + 3) / 4;
+  auto* outputRow = static_cast<uint8_t*>(malloc(outputRowSize));
+  auto* rowBytes = static_cast<uint8_t*>(malloc(bitmap.getRowBytes()));
+
+  if (!outputRow || !rowBytes) {
+    Serial.printf("[%lu] [GFX] !! Failed to allocate 1-bit BMP row buffers\n", millis());
+    free(outputRow);
+    free(rowBytes);
+    return;
+  }
+
+  for (int bmpY = 0; bmpY < bitmap.getHeight(); bmpY++) {
+    // Read rows sequentially using readNextRow
+    if (bitmap.readNextRow(outputRow, rowBytes) != BmpReaderError::Ok) {
+      Serial.printf("[%lu] [GFX] Failed to read row %d from 1-bit bitmap\n", millis(), bmpY);
+      free(outputRow);
+      free(rowBytes);
+      return;
+    }
+
+    // Calculate screen Y based on whether BMP is top-down or bottom-up
+    const int bmpYOffset = bitmap.isTopDown() ? bmpY : bitmap.getHeight() - 1 - bmpY;
+    int screenY = y + (isScaled ? static_cast<int>(std::floor(bmpYOffset * scale)) : bmpYOffset);
+    if (screenY >= getScreenHeight()) {
+      continue;  // Continue reading to keep row counter in sync
+    }
+    if (screenY < 0) {
+      continue;
+    }
+
+    for (int bmpX = 0; bmpX < bitmap.getWidth(); bmpX++) {
+      int screenX = x + (isScaled ? static_cast<int>(std::floor(bmpX * scale)) : bmpX);
+      if (screenX >= getScreenWidth()) {
+        break;
+      }
+      if (screenX < 0) {
+        continue;
+      }
+
+      // Get 2-bit value (result of readNextRow quantization)
+      const uint8_t val = outputRow[bmpX / 4] >> (6 - ((bmpX * 2) % 8)) & 0x3;
+
+      // For 1-bit source: 0 or 1 -> map to black (0,1,2) or white (3)
+      // val < 3 means black pixel (draw it)
+      if (val < 3) {
+        drawPixel(screenX, screenY, true);
+      }
+      // White pixels (val == 3) are not drawn (leave background)
+    }
+  }
+
+  free(outputRow);
+  free(rowBytes);
+}
+
+void GfxRenderer::fillPolygon(const int* xPoints, const int* yPoints, int numPoints, bool state) const {
+  if (numPoints < 3) return;
+
+  // Find bounding box
+  int minY = yPoints[0], maxY = yPoints[0];
+  for (int i = 1; i < numPoints; i++) {
+    if (yPoints[i] < minY) minY = yPoints[i];
+    if (yPoints[i] > maxY) maxY = yPoints[i];
+  }
+
+  // Clip to screen
+  if (minY < 0) minY = 0;
+  if (maxY >= getScreenHeight()) maxY = getScreenHeight() - 1;
+
+  // Allocate node buffer for scanline algorithm
+  auto* nodeX = static_cast<int*>(malloc(numPoints * sizeof(int)));
+  if (!nodeX) {
+    Serial.printf("[%lu] [GFX] !! Failed to allocate polygon node buffer\n", millis());
+    return;
+  }
+
+  // Scanline fill algorithm
+  for (int scanY = minY; scanY <= maxY; scanY++) {
+    int nodes = 0;
+
+    // Find all intersection points with edges
+    int j = numPoints - 1;
+    for (int i = 0; i < numPoints; i++) {
+      if ((yPoints[i] < scanY && yPoints[j] >= scanY) || (yPoints[j] < scanY && yPoints[i] >= scanY)) {
+        // Calculate X intersection using fixed-point to avoid float
+        int dy = yPoints[j] - yPoints[i];
+        if (dy != 0) {
+          nodeX[nodes++] = xPoints[i] + (scanY - yPoints[i]) * (xPoints[j] - xPoints[i]) / dy;
+        }
+      }
+      j = i;
+    }
+
+    // Sort nodes by X (simple bubble sort, numPoints is small)
+    for (int i = 0; i < nodes - 1; i++) {
+      for (int k = i + 1; k < nodes; k++) {
+        if (nodeX[i] > nodeX[k]) {
+          int temp = nodeX[i];
+          nodeX[i] = nodeX[k];
+          nodeX[k] = temp;
+        }
+      }
+    }
+
+    // Fill between pairs of nodes
+    for (int i = 0; i < nodes - 1; i += 2) {
+      int startX = nodeX[i];
+      int endX = nodeX[i + 1];
+
+      // Clip to screen
+      if (startX < 0) startX = 0;
+      if (endX >= getScreenWidth()) endX = getScreenWidth() - 1;
+
+      // Draw horizontal line
+      for (int x = startX; x <= endX; x++) {
+        drawPixel(x, scanY, state);
+      }
+    }
+  }
+
+  free(nodeX);
+}
+
 void GfxRenderer::clearScreen(const uint8_t color) const { einkDisplay.clearScreen(color); }
 
 void GfxRenderer::invertScreen() const {

lib/GfxRenderer/GfxRenderer.h

@@ -68,6 +68,8 @@ class GfxRenderer {
   void drawImage(const uint8_t bitmap[], int x, int y, int width, int height) const;
   void drawBitmap(const Bitmap& bitmap, int x, int y, int maxWidth, int maxHeight, float cropX = 0,
                   float cropY = 0) const;
+  void drawBitmap1Bit(const Bitmap& bitmap, int x, int y, int maxWidth, int maxHeight) const;
+  void fillPolygon(const int* xPoints, const int* yPoints, int numPoints, bool state = true) const;
 
   // Text
   int getTextWidth(int fontId, const char* text, EpdFontFamily::Style style = EpdFontFamily::REGULAR) const;
@@ -97,8 +99,8 @@ class GfxRenderer {
   void copyGrayscaleLsbBuffers() const;
   void copyGrayscaleMsbBuffers() const;
   void displayGrayBuffer() const;
-  bool storeBwBuffer();  // Returns true if buffer was stored successfully
-  void restoreBwBuffer();
+  bool storeBwBuffer();    // Returns true if buffer was stored successfully
+  void restoreBwBuffer();  // Restore and free the stored buffer
   void cleanupGrayscaleWithFrameBuffer() const;
 
   // Low level functions

lib/JpegToBmpConverter/JpegToBmpConverter.cpp

@@ -114,6 +114,96 @@ static inline uint8_t quantize(int gray, int x, int y) {
   }
 }
 
+// 1-bit noise dithering for fast home screen rendering
+// Uses hash-based noise for consistent dithering that works well at small sizes
+static inline uint8_t quantize1bit(int gray, int x, int y) {
+  gray = adjustPixel(gray);
+
+  // Generate noise threshold using integer hash (no regular pattern to alias)
+  uint32_t hash = static_cast<uint32_t>(x) * 374761393u + static_cast<uint32_t>(y) * 668265263u;
+  hash = (hash ^ (hash >> 13)) * 1274126177u;
+  const int threshold = static_cast<int>(hash >> 24);  // 0-255
+
+  // Simple threshold with noise: gray >= (128 + noise offset) -> white
+  // The noise adds variation around the 128 midpoint
+  const int adjustedThreshold = 128 + ((threshold - 128) / 2);  // Range: 64-192
+  return (gray >= adjustedThreshold) ? 1 : 0;
+}
+
+// 1-bit Atkinson dithering - better quality than noise dithering for thumbnails
+// Error distribution pattern (same as 2-bit but quantizes to 2 levels):
+//     X  1/8 1/8
+// 1/8 1/8 1/8
+//     1/8
+class Atkinson1BitDitherer {
+ public:
+  Atkinson1BitDitherer(int width) : width(width) {
+    errorRow0 = new int16_t[width + 4]();  // Current row
+    errorRow1 = new int16_t[width + 4]();  // Next row
+    errorRow2 = new int16_t[width + 4]();  // Row after next
+  }
+
+  ~Atkinson1BitDitherer() {
+    delete[] errorRow0;
+    delete[] errorRow1;
+    delete[] errorRow2;
+  }
+
+  uint8_t processPixel(int gray, int x) {
+    // Apply brightness/contrast/gamma adjustments
+    gray = adjustPixel(gray);
+
+    // Add accumulated error
+    int adjusted = gray + errorRow0[x + 2];
+    if (adjusted < 0) adjusted = 0;
+    if (adjusted > 255) adjusted = 255;
+
+    // Quantize to 2 levels (1-bit): 0 = black, 1 = white
+    uint8_t quantized;
+    int quantizedValue;
+    if (adjusted < 128) {
+      quantized = 0;
+      quantizedValue = 0;
+    } else {
+      quantized = 1;
+      quantizedValue = 255;
+    }
+
+    // Calculate error (only distribute 6/8 = 75%)
+    int error = (adjusted - quantizedValue) >> 3;  // error/8
+
+    // Distribute 1/8 to each of 6 neighbors
+    errorRow0[x + 3] += error;  // Right
+    errorRow0[x + 4] += error;  // Right+1
+    errorRow1[x + 1] += error;  // Bottom-left
+    errorRow1[x + 2] += error;  // Bottom
+    errorRow1[x + 3] += error;  // Bottom-right
+    errorRow2[x + 2] += error;  // Two rows down
+
+    return quantized;
+  }
+
+  void nextRow() {
+    int16_t* temp = errorRow0;
+    errorRow0 = errorRow1;
+    errorRow1 = errorRow2;
+    errorRow2 = temp;
+    memset(errorRow2, 0, (width + 4) * sizeof(int16_t));
+  }
+
+  void reset() {
+    memset(errorRow0, 0, (width + 4) * sizeof(int16_t));
+    memset(errorRow1, 0, (width + 4) * sizeof(int16_t));
+    memset(errorRow2, 0, (width + 4) * sizeof(int16_t));
+  }
+
+ private:
+  int width;
+  int16_t* errorRow0;
+  int16_t* errorRow1;
+  int16_t* errorRow2;
+};
+
 // Atkinson dithering - distributes only 6/8 (75%) of error for cleaner results
 // Error distribution pattern:
 //     X  1/8 1/8
@@ -355,8 +445,47 @@ void writeBmpHeader8bit(Print& bmpOut, const int width, const int height) {
   }
 }
 
+// Helper function: Write BMP header with 1-bit color depth (black and white)
+static void writeBmpHeader1bit(Print& bmpOut, const int width, const int height) {
+  // Calculate row padding (each row must be multiple of 4 bytes)
+  const int bytesPerRow = (width + 31) / 32 * 4;  // 1 bit per pixel, round up to 4-byte boundary
+  const int imageSize = bytesPerRow * height;
+  const uint32_t fileSize = 62 + imageSize;  // 14 (file header) + 40 (DIB header) + 8 (palette) + image
+
+  // BMP File Header (14 bytes)
+  bmpOut.write('B');
+  bmpOut.write('M');
+  write32(bmpOut, fileSize);  // File size
+  write32(bmpOut, 0);         // Reserved
+  write32(bmpOut, 62);        // Offset to pixel data (14 + 40 + 8)
+
+  // DIB Header (BITMAPINFOHEADER - 40 bytes)
+  write32(bmpOut, 40);
+  write32Signed(bmpOut, width);
+  write32Signed(bmpOut, -height);  // Negative height = top-down bitmap
+  write16(bmpOut, 1);              // Color planes
+  write16(bmpOut, 1);              // Bits per pixel (1 bit)
+  write32(bmpOut, 0);              // BI_RGB (no compression)
+  write32(bmpOut, imageSize);
+  write32(bmpOut, 2835);  // xPixelsPerMeter (72 DPI)
+  write32(bmpOut, 2835);  // yPixelsPerMeter (72 DPI)
+  write32(bmpOut, 2);     // colorsUsed
+  write32(bmpOut, 2);     // colorsImportant
+
+  // Color Palette (2 colors x 4 bytes = 8 bytes)
+  // Format: Blue, Green, Red, Reserved (BGRA)
+  // Note: In 1-bit BMP, palette index 0 = black, 1 = white
+  uint8_t palette[8] = {
+      0x00, 0x00, 0x00, 0x00,  // Color 0: Black
+      0xFF, 0xFF, 0xFF, 0x00   // Color 1: White
+  };
+  for (const uint8_t i : palette) {
+    bmpOut.write(i);
+  }
+}
+
 // Helper function: Write BMP header with 2-bit color depth
-void JpegToBmpConverter::writeBmpHeader(Print& bmpOut, const int width, const int height) {
+static void writeBmpHeader2bit(Print& bmpOut, const int width, const int height) {
   // Calculate row padding (each row must be multiple of 4 bytes)
   const int bytesPerRow = (width * 2 + 31) / 32 * 4;  // 2 bits per pixel, round up
   const int imageSize = bytesPerRow * height;
@@ -427,9 +556,11 @@ unsigned char JpegToBmpConverter::jpegReadCallback(unsigned char* pBuf, const un
   return 0;  // Success
 }
 
-// Core function: Convert JPEG file to 2-bit BMP
-bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut) {
-  Serial.printf("[%lu] [JPG] Converting JPEG to BMP\n", millis());
+// Internal implementation with configurable target size and bit depth
+bool JpegToBmpConverter::jpegFileToBmpStreamInternal(FsFile& jpegFile, Print& bmpOut, int targetWidth, int targetHeight,
+                                                     bool oneBit) {
+  Serial.printf("[%lu] [JPG] Converting JPEG to %s BMP (target: %dx%d)\n", millis(), oneBit ? "1-bit" : "2-bit",
+                targetWidth, targetHeight);
 
   // Setup context for picojpeg callback
   JpegReadContext context = {.file = jpegFile, .bufferPos = 0, .bufferFilled = 0};
@@ -464,10 +595,10 @@ bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut) {
   uint32_t scaleY_fp = 65536;
   bool needsScaling = false;
 
-  if (USE_PRESCALE && (imageInfo.m_width > TARGET_MAX_WIDTH || imageInfo.m_height > TARGET_MAX_HEIGHT)) {
+  if (targetWidth > 0 && targetHeight > 0 && (imageInfo.m_width > targetWidth || imageInfo.m_height > targetHeight)) {
     // Calculate scale to fit within target dimensions while maintaining aspect ratio
-    const float scaleToFitWidth = static_cast<float>(TARGET_MAX_WIDTH) / imageInfo.m_width;
-    const float scaleToFitHeight = static_cast<float>(TARGET_MAX_HEIGHT) / imageInfo.m_height;
+    const float scaleToFitWidth = static_cast<float>(targetWidth) / imageInfo.m_width;
+    const float scaleToFitHeight = static_cast<float>(targetHeight) / imageInfo.m_height;
     // We scale to the smaller dimension, so we can potentially crop later.
     // TODO: ideally, we already crop here.
     const float scale = (scaleToFitWidth > scaleToFitHeight) ? scaleToFitWidth : scaleToFitHeight;
@@ -486,16 +617,19 @@ bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut) {
     needsScaling = true;
 
     Serial.printf("[%lu] [JPG] Pre-scaling %dx%d -> %dx%d (fit to %dx%d)\n", millis(), imageInfo.m_width,
-                  imageInfo.m_height, outWidth, outHeight, TARGET_MAX_WIDTH, TARGET_MAX_HEIGHT);
+                  imageInfo.m_height, outWidth, outHeight, targetWidth, targetHeight);
   }
 
   // Write BMP header with output dimensions
   int bytesPerRow;
-  if (USE_8BIT_OUTPUT) {
+  if (USE_8BIT_OUTPUT && !oneBit) {
     writeBmpHeader8bit(bmpOut, outWidth, outHeight);
     bytesPerRow = (outWidth + 3) / 4 * 4;
+  } else if (oneBit) {
+    writeBmpHeader1bit(bmpOut, outWidth, outHeight);
+    bytesPerRow = (outWidth + 31) / 32 * 4;  // 1 bit per pixel
   } else {
-    writeBmpHeader(bmpOut, outWidth, outHeight);
+    writeBmpHeader2bit(bmpOut, outWidth, outHeight);
     bytesPerRow = (outWidth * 2 + 31) / 32 * 4;
   }
 
@@ -526,11 +660,16 @@ bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut) {
     return false;
   }
 
-  // Create ditherer if enabled (only for 2-bit output)
+  // Create ditherer if enabled
   // Use OUTPUT dimensions for dithering (after prescaling)
   AtkinsonDitherer* atkinsonDitherer = nullptr;
   FloydSteinbergDitherer* fsDitherer = nullptr;
-  if (!USE_8BIT_OUTPUT) {
+  Atkinson1BitDitherer* atkinson1BitDitherer = nullptr;
+
+  if (oneBit) {
+    // For 1-bit output, use Atkinson dithering for better quality
+    atkinson1BitDitherer = new Atkinson1BitDitherer(outWidth);
+  } else if (!USE_8BIT_OUTPUT) {
     if (USE_ATKINSON) {
       atkinsonDitherer = new AtkinsonDitherer(outWidth);
     } else if (USE_FLOYD_STEINBERG) {
@@ -616,12 +755,25 @@ bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut) {
         // No scaling - direct output (1:1 mapping)
         memset(rowBuffer, 0, bytesPerRow);
 
-        if (USE_8BIT_OUTPUT) {
+        if (USE_8BIT_OUTPUT && !oneBit) {
           for (int x = 0; x < outWidth; x++) {
             const uint8_t gray = mcuRowBuffer[bufferY * imageInfo.m_width + x];
             rowBuffer[x] = adjustPixel(gray);
           }
+        } else if (oneBit) {
+          // 1-bit output with Atkinson dithering for better quality
+          for (int x = 0; x < outWidth; x++) {
+            const uint8_t gray = mcuRowBuffer[bufferY * imageInfo.m_width + x];
+            const uint8_t bit =
+                atkinson1BitDitherer ? atkinson1BitDitherer->processPixel(gray, x) : quantize1bit(gray, x, y);
+            // Pack 1-bit value: MSB first, 8 pixels per byte
+            const int byteIndex = x / 8;
+            const int bitOffset = 7 - (x % 8);
+            rowBuffer[byteIndex] |= (bit << bitOffset);
+          }
+          if (atkinson1BitDitherer) atkinson1BitDitherer->nextRow();
         } else {
+          // 2-bit output
           for (int x = 0; x < outWidth; x++) {
             const uint8_t gray = mcuRowBuffer[bufferY * imageInfo.m_width + x];
             uint8_t twoBit;
@@ -679,12 +831,25 @@ bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut) {
         if (srcY_fp >= nextOutY_srcStart && currentOutY < outHeight) {
           memset(rowBuffer, 0, bytesPerRow);
 
-          if (USE_8BIT_OUTPUT) {
+          if (USE_8BIT_OUTPUT && !oneBit) {
             for (int x = 0; x < outWidth; x++) {
               const uint8_t gray = (rowCount[x] > 0) ? (rowAccum[x] / rowCount[x]) : 0;
               rowBuffer[x] = adjustPixel(gray);
             }
+          } else if (oneBit) {
+            // 1-bit output with Atkinson dithering for better quality
+            for (int x = 0; x < outWidth; x++) {
+              const uint8_t gray = (rowCount[x] > 0) ? (rowAccum[x] / rowCount[x]) : 0;
+              const uint8_t bit = atkinson1BitDitherer ? atkinson1BitDitherer->processPixel(gray, x)
+                                                       : quantize1bit(gray, x, currentOutY);
+              // Pack 1-bit value: MSB first, 8 pixels per byte
+              const int byteIndex = x / 8;
+              const int bitOffset = 7 - (x % 8);
+              rowBuffer[byteIndex] |= (bit << bitOffset);
+            }
+            if (atkinson1BitDitherer) atkinson1BitDitherer->nextRow();
           } else {
+            // 2-bit output
             for (int x = 0; x < outWidth; x++) {
               const uint8_t gray = (rowCount[x] > 0) ? (rowAccum[x] / rowCount[x]) : 0;
               uint8_t twoBit;
@@ -732,9 +897,29 @@ bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut) {
   if (fsDitherer) {
     delete fsDitherer;
   }
+  if (atkinson1BitDitherer) {
+    delete atkinson1BitDitherer;
+  }
   free(mcuRowBuffer);
   free(rowBuffer);
 
   Serial.printf("[%lu] [JPG] Successfully converted JPEG to BMP\n", millis());
   return true;
 }
+
+// Core function: Convert JPEG file to 2-bit BMP (uses default target size)
+bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut) {
+  return jpegFileToBmpStreamInternal(jpegFile, bmpOut, TARGET_MAX_WIDTH, TARGET_MAX_HEIGHT, false);
+}
+
+// Convert with custom target size (for thumbnails, 2-bit)
+bool JpegToBmpConverter::jpegFileToBmpStreamWithSize(FsFile& jpegFile, Print& bmpOut, int targetMaxWidth,
+                                                     int targetMaxHeight) {
+  return jpegFileToBmpStreamInternal(jpegFile, bmpOut, targetMaxWidth, targetMaxHeight, false);
+}
+
+// Convert to 1-bit BMP (black and white only, no grays) for fast home screen rendering
+bool JpegToBmpConverter::jpegFileTo1BitBmpStreamWithSize(FsFile& jpegFile, Print& bmpOut, int targetMaxWidth,
+                                                         int targetMaxHeight) {
+  return jpegFileToBmpStreamInternal(jpegFile, bmpOut, targetMaxWidth, targetMaxHeight, true);
+}

lib/JpegToBmpConverter/JpegToBmpConverter.h

@@ -5,11 +5,15 @@ class Print;
 class ZipFile;
 
 class JpegToBmpConverter {
-  static void writeBmpHeader(Print& bmpOut, int width, int height);
-  // [COMMENTED OUT] static uint8_t grayscaleTo2Bit(uint8_t grayscale, int x, int y);
   static unsigned char jpegReadCallback(unsigned char* pBuf, unsigned char buf_size,
                                         unsigned char* pBytes_actually_read, void* pCallback_data);
+  static bool jpegFileToBmpStreamInternal(class FsFile& jpegFile, Print& bmpOut, int targetWidth, int targetHeight,
+                                          bool oneBit);
 
  public:
   static bool jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut);
+  // Convert with custom target size (for thumbnails)
+  static bool jpegFileToBmpStreamWithSize(FsFile& jpegFile, Print& bmpOut, int targetMaxWidth, int targetMaxHeight);
+  // Convert to 1-bit BMP (black and white only, no grays) for fast home screen rendering
+  static bool jpegFileTo1BitBmpStreamWithSize(FsFile& jpegFile, Print& bmpOut, int targetMaxWidth, int targetMaxHeight);
 };

lib/Xtc/Xtc.cpp

@@ -293,6 +293,267 @@ bool Xtc::generateCoverBmp() const {
   return true;
 }
 
+std::string Xtc::getThumbBmpPath() const { return cachePath + "/thumb.bmp"; }
+
+bool Xtc::generateThumbBmp() const {
+  // Already generated
+  if (SdMan.exists(getThumbBmpPath().c_str())) {
+    return true;
+  }
+
+  if (!loaded || !parser) {
+    Serial.printf("[%lu] [XTC] Cannot generate thumb BMP, file not loaded\n", millis());
+    return false;
+  }
+
+  if (parser->getPageCount() == 0) {
+    Serial.printf("[%lu] [XTC] No pages in XTC file\n", millis());
+    return false;
+  }
+
+  // Setup cache directory
+  setupCacheDir();
+
+  // Get first page info for cover
+  xtc::PageInfo pageInfo;
+  if (!parser->getPageInfo(0, pageInfo)) {
+    Serial.printf("[%lu] [XTC] Failed to get first page info\n", millis());
+    return false;
+  }
+
+  // Get bit depth
+  const uint8_t bitDepth = parser->getBitDepth();
+
+  // Calculate target dimensions for thumbnail (fit within 240x400 Continue Reading card)
+  constexpr int THUMB_TARGET_WIDTH = 240;
+  constexpr int THUMB_TARGET_HEIGHT = 400;
+
+  // Calculate scale factor
+  float scaleX = static_cast<float>(THUMB_TARGET_WIDTH) / pageInfo.width;
+  float scaleY = static_cast<float>(THUMB_TARGET_HEIGHT) / pageInfo.height;
+  float scale = (scaleX < scaleY) ? scaleX : scaleY;
+
+  // Only scale down, never up
+  if (scale >= 1.0f) {
+    // Page is already small enough, just use cover.bmp
+    // Copy cover.bmp to thumb.bmp
+    if (generateCoverBmp()) {
+      FsFile src, dst;
+      if (SdMan.openFileForRead("XTC", getCoverBmpPath(), src)) {
+        if (SdMan.openFileForWrite("XTC", getThumbBmpPath(), dst)) {
+          uint8_t buffer[512];
+          while (src.available()) {
+            size_t bytesRead = src.read(buffer, sizeof(buffer));
+            dst.write(buffer, bytesRead);
+          }
+          dst.close();
+        }
+        src.close();
+      }
+      Serial.printf("[%lu] [XTC] Copied cover to thumb (no scaling needed)\n", millis());
+      return SdMan.exists(getThumbBmpPath().c_str());
+    }
+    return false;
+  }
+
+  uint16_t thumbWidth = static_cast<uint16_t>(pageInfo.width * scale);
+  uint16_t thumbHeight = static_cast<uint16_t>(pageInfo.height * scale);
+
+  Serial.printf("[%lu] [XTC] Generating thumb BMP: %dx%d -> %dx%d (scale: %.3f)\n", millis(), pageInfo.width,
+                pageInfo.height, thumbWidth, thumbHeight, scale);
+
+  // Allocate buffer for page data
+  size_t bitmapSize;
+  if (bitDepth == 2) {
+    bitmapSize = ((static_cast<size_t>(pageInfo.width) * pageInfo.height + 7) / 8) * 2;
+  } else {
+    bitmapSize = ((pageInfo.width + 7) / 8) * pageInfo.height;
+  }
+  uint8_t* pageBuffer = static_cast<uint8_t*>(malloc(bitmapSize));
+  if (!pageBuffer) {
+    Serial.printf("[%lu] [XTC] Failed to allocate page buffer (%lu bytes)\n", millis(), bitmapSize);
+    return false;
+  }
+
+  // Load first page (cover)
+  size_t bytesRead = const_cast<xtc::XtcParser*>(parser.get())->loadPage(0, pageBuffer, bitmapSize);
+  if (bytesRead == 0) {
+    Serial.printf("[%lu] [XTC] Failed to load cover page for thumb\n", millis());
+    free(pageBuffer);
+    return false;
+  }
+
+  // Create thumbnail BMP file - use 1-bit format for fast home screen rendering (no gray passes)
+  FsFile thumbBmp;
+  if (!SdMan.openFileForWrite("XTC", getThumbBmpPath(), thumbBmp)) {
+    Serial.printf("[%lu] [XTC] Failed to create thumb BMP file\n", millis());
+    free(pageBuffer);
+    return false;
+  }
+
+  // Write 1-bit BMP header for fast home screen rendering
+  const uint32_t rowSize = (thumbWidth + 31) / 32 * 4;  // 1 bit per pixel, aligned to 4 bytes
+  const uint32_t imageSize = rowSize * thumbHeight;
+  const uint32_t fileSize = 14 + 40 + 8 + imageSize;  // 8 bytes for 2-color palette
+
+  // File header
+  thumbBmp.write('B');
+  thumbBmp.write('M');
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&fileSize), 4);
+  uint32_t reserved = 0;
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&reserved), 4);
+  uint32_t dataOffset = 14 + 40 + 8;  // 1-bit palette has 2 colors (8 bytes)
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&dataOffset), 4);
+
+  // DIB header
+  uint32_t dibHeaderSize = 40;
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&dibHeaderSize), 4);
+  int32_t widthVal = thumbWidth;
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&widthVal), 4);
+  int32_t heightVal = -static_cast<int32_t>(thumbHeight);  // Negative for top-down
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&heightVal), 4);
+  uint16_t planes = 1;
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&planes), 2);
+  uint16_t bitsPerPixel = 1;  // 1-bit for black and white
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&bitsPerPixel), 2);
+  uint32_t compression = 0;
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&compression), 4);
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&imageSize), 4);
+  int32_t ppmX = 2835;
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&ppmX), 4);
+  int32_t ppmY = 2835;
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&ppmY), 4);
+  uint32_t colorsUsed = 2;
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&colorsUsed), 4);
+  uint32_t colorsImportant = 2;
+  thumbBmp.write(reinterpret_cast<const uint8_t*>(&colorsImportant), 4);
+
+  // Color palette (2 colors for 1-bit: black and white)
+  uint8_t palette[8] = {
+      0x00, 0x00, 0x00, 0x00,  // Color 0: Black
+      0xFF, 0xFF, 0xFF, 0x00   // Color 1: White
+  };
+  thumbBmp.write(palette, 8);
+
+  // Allocate row buffer for 1-bit output
+  uint8_t* rowBuffer = static_cast<uint8_t*>(malloc(rowSize));
+  if (!rowBuffer) {
+    free(pageBuffer);
+    thumbBmp.close();
+    return false;
+  }
+
+  // Fixed-point scale factor (16.16)
+  uint32_t scaleInv_fp = static_cast<uint32_t>(65536.0f / scale);
+
+  // Pre-calculate plane info for 2-bit mode
+  const size_t planeSize = (bitDepth == 2) ? ((static_cast<size_t>(pageInfo.width) * pageInfo.height + 7) / 8) : 0;
+  const uint8_t* plane1 = (bitDepth == 2) ? pageBuffer : nullptr;
+  const uint8_t* plane2 = (bitDepth == 2) ? pageBuffer + planeSize : nullptr;
+  const size_t colBytes = (bitDepth == 2) ? ((pageInfo.height + 7) / 8) : 0;
+  const size_t srcRowBytes = (bitDepth == 1) ? ((pageInfo.width + 7) / 8) : 0;
+
+  for (uint16_t dstY = 0; dstY < thumbHeight; dstY++) {
+    memset(rowBuffer, 0xFF, rowSize);  // Start with all white (bit 1)
+
+    // Calculate source Y range with bounds checking
+    uint32_t srcYStart = (static_cast<uint32_t>(dstY) * scaleInv_fp) >> 16;
+    uint32_t srcYEnd = (static_cast<uint32_t>(dstY + 1) * scaleInv_fp) >> 16;
+    if (srcYStart >= pageInfo.height) srcYStart = pageInfo.height - 1;
+    if (srcYEnd > pageInfo.height) srcYEnd = pageInfo.height;
+    if (srcYEnd <= srcYStart) srcYEnd = srcYStart + 1;
+    if (srcYEnd > pageInfo.height) srcYEnd = pageInfo.height;
+
+    for (uint16_t dstX = 0; dstX < thumbWidth; dstX++) {
+      // Calculate source X range with bounds checking
+      uint32_t srcXStart = (static_cast<uint32_t>(dstX) * scaleInv_fp) >> 16;
+      uint32_t srcXEnd = (static_cast<uint32_t>(dstX + 1) * scaleInv_fp) >> 16;
+      if (srcXStart >= pageInfo.width) srcXStart = pageInfo.width - 1;
+      if (srcXEnd > pageInfo.width) srcXEnd = pageInfo.width;
+      if (srcXEnd <= srcXStart) srcXEnd = srcXStart + 1;
+      if (srcXEnd > pageInfo.width) srcXEnd = pageInfo.width;
+
+      // Area averaging: sum grayscale values (0-255 range)
+      uint32_t graySum = 0;
+      uint32_t totalCount = 0;
+
+      for (uint32_t srcY = srcYStart; srcY < srcYEnd && srcY < pageInfo.height; srcY++) {
+        for (uint32_t srcX = srcXStart; srcX < srcXEnd && srcX < pageInfo.width; srcX++) {
+          uint8_t grayValue = 255;  // Default: white
+
+          if (bitDepth == 2) {
+            // XTH 2-bit mode: pixel value 0-3
+            // Bounds check for column index
+            if (srcX < pageInfo.width) {
+              const size_t colIndex = pageInfo.width - 1 - srcX;
+              const size_t byteInCol = srcY / 8;
+              const size_t bitInByte = 7 - (srcY % 8);
+              const size_t byteOffset = colIndex * colBytes + byteInCol;
+              // Bounds check for buffer access
+              if (byteOffset < planeSize) {
+                const uint8_t bit1 = (plane1[byteOffset] >> bitInByte) & 1;
+                const uint8_t bit2 = (plane2[byteOffset] >> bitInByte) & 1;
+                const uint8_t pixelValue = (bit1 << 1) | bit2;
+                // Convert 2-bit (0-3) to grayscale: 0=black, 3=white
+                // pixelValue: 0=white, 1=light gray, 2=dark gray, 3=black (XTC polarity)
+                grayValue = (3 - pixelValue) * 85;  // 0->255, 1->170, 2->85, 3->0
+              }
+            }
+          } else {
+            // 1-bit mode
+            const size_t byteIdx = srcY * srcRowBytes + srcX / 8;
+            const size_t bitIdx = 7 - (srcX % 8);
+            // Bounds check for buffer access
+            if (byteIdx < bitmapSize) {
+              const uint8_t pixelBit = (pageBuffer[byteIdx] >> bitIdx) & 1;
+              // XTC polarity: 1=black, 0=white
+              grayValue = pixelBit ? 0 : 255;
+            }
+          }
+
+          graySum += grayValue;
+          totalCount++;
+        }
+      }
+
+      // Calculate average grayscale and quantize to 1-bit with noise dithering
+      uint8_t avgGray = (totalCount > 0) ? static_cast<uint8_t>(graySum / totalCount) : 255;
+
+      // Hash-based noise dithering for 1-bit output
+      uint32_t hash = static_cast<uint32_t>(dstX) * 374761393u + static_cast<uint32_t>(dstY) * 668265263u;
+      hash = (hash ^ (hash >> 13)) * 1274126177u;
+      const int threshold = static_cast<int>(hash >> 24);           // 0-255
+      const int adjustedThreshold = 128 + ((threshold - 128) / 2);  // Range: 64-192
+
+      // Quantize to 1-bit: 0=black, 1=white
+      uint8_t oneBit = (avgGray >= adjustedThreshold) ? 1 : 0;
+
+      // Pack 1-bit value into row buffer (MSB first, 8 pixels per byte)
+      const size_t byteIndex = dstX / 8;
+      const size_t bitOffset = 7 - (dstX % 8);
+      // Bounds check for row buffer access
+      if (byteIndex < rowSize) {
+        if (oneBit) {
+          rowBuffer[byteIndex] |= (1 << bitOffset);  // Set bit for white
+        } else {
+          rowBuffer[byteIndex] &= ~(1 << bitOffset);  // Clear bit for black
+        }
+      }
+    }
+
+    // Write row (already padded to 4-byte boundary by rowSize)
+    thumbBmp.write(rowBuffer, rowSize);
+  }
+
+  free(rowBuffer);
+  thumbBmp.close();
+  free(pageBuffer);
+
+  Serial.printf("[%lu] [XTC] Generated thumb BMP (%dx%d): %s\n", millis(), thumbWidth, thumbHeight,
+                getThumbBmpPath().c_str());
+  return true;
+}
+
 uint32_t Xtc::getPageCount() const {
   if (!loaded || !parser) {
     return 0;

lib/Xtc/Xtc.h

@@ -62,6 +62,9 @@ class Xtc {
   // Cover image support (for sleep screen)
   std::string getCoverBmpPath() const;
   bool generateCoverBmp() const;
+  // Thumbnail support (for Continue Reading card)
+  std::string getThumbBmpPath() const;
+  bool generateThumbBmp() const;
 
   // Page access
   uint32_t getPageCount() const;

src/activities/home/HomeActivity.cpp

@@ -1,8 +1,10 @@
 #include "HomeActivity.h"
 
+#include <Bitmap.h>
 #include <Epub.h>
 #include <GfxRenderer.h>
 #include <SDCardManager.h>
+#include <Xtc.h>
 
 #include <cstring>
 #include <vector>
@@ -15,6 +17,29 @@
 #include "fontIds.h"
 #include "util/StringUtils.h"
 
+namespace {
+// UTF-8 safe string truncation - removes one character from the end
+// Returns the new size after removing one UTF-8 character
+size_t utf8RemoveLastChar(std::string& str) {
+  if (str.empty()) return 0;
+  size_t pos = str.size() - 1;
+  // Walk back to find the start of the last UTF-8 character
+  // UTF-8 continuation bytes start with 10xxxxxx (0x80-0xBF)
+  while (pos > 0 && (static_cast<unsigned char>(str[pos]) & 0xC0) == 0x80) {
+    --pos;
+  }
+  str.resize(pos);
+  return pos;
+}
+
+// Truncate string by removing N UTF-8 characters from the end
+void utf8TruncateChars(std::string& str, size_t numChars) {
+  for (size_t i = 0; i < numChars && !str.empty(); ++i) {
+    utf8RemoveLastChar(str);
+  }
+}
+}  // namespace
+
 void HomeActivity::taskTrampoline(void* param) {
   auto* self = static_cast<HomeActivity*>(param);
   self->displayTaskLoop();
@@ -46,7 +71,7 @@ void HomeActivity::onEnter() {
       lastBookTitle = lastBookTitle.substr(lastSlash + 1);
     }
 
-    // If epub, try to load the metadata for title/author
+    // If epub, try to load the metadata for title/author and cover
     if (StringUtils::checkFileExtension(lastBookTitle, ".epub")) {
       Epub epub(APP_STATE.openEpubPath, "/.crosspoint");
       epub.load(false);
@@ -56,10 +81,31 @@ void HomeActivity::onEnter() {
       if (!epub.getAuthor().empty()) {
         lastBookAuthor = std::string(epub.getAuthor());
       }
-    } else if (StringUtils::checkFileExtension(lastBookTitle, ".xtch")) {
-      lastBookTitle.resize(lastBookTitle.length() - 5);
-    } else if (StringUtils::checkFileExtension(lastBookTitle, ".xtc")) {
-      lastBookTitle.resize(lastBookTitle.length() - 4);
+      // Try to generate thumbnail image for Continue Reading card
+      if (epub.generateThumbBmp()) {
+        coverBmpPath = epub.getThumbBmpPath();
+        hasCoverImage = true;
+      }
+    } else if (StringUtils::checkFileExtension(lastBookTitle, ".xtch") ||
+               StringUtils::checkFileExtension(lastBookTitle, ".xtc")) {
+      // Handle XTC file
+      Xtc xtc(APP_STATE.openEpubPath, "/.crosspoint");
+      if (xtc.load()) {
+        if (!xtc.getTitle().empty()) {
+          lastBookTitle = std::string(xtc.getTitle());
+        }
+        // Try to generate thumbnail image for Continue Reading card
+        if (xtc.generateThumbBmp()) {
+          coverBmpPath = xtc.getThumbBmpPath();
+          hasCoverImage = true;
+        }
+      }
+      // Remove extension from title if we don't have metadata
+      if (StringUtils::checkFileExtension(lastBookTitle, ".xtch")) {
+        lastBookTitle.resize(lastBookTitle.length() - 5);
+      } else if (StringUtils::checkFileExtension(lastBookTitle, ".xtc")) {
+        lastBookTitle.resize(lastBookTitle.length() - 4);
+      }
     }
   }
 
@@ -69,7 +115,7 @@ void HomeActivity::onEnter() {
   updateRequired = true;
 
   xTaskCreate(&HomeActivity::taskTrampoline, "HomeActivityTask",
-              2048,               // Stack size
+              4096,               // Stack size (increased for cover image rendering)
               this,               // Parameters
               1,                  // Priority
               &displayTaskHandle  // Task handle
@@ -87,6 +133,51 @@ void HomeActivity::onExit() {
   }
   vSemaphoreDelete(renderingMutex);
   renderingMutex = nullptr;
+
+  // Free the stored cover buffer if any
+  freeCoverBuffer();
+}
+
+bool HomeActivity::storeCoverBuffer() {
+  uint8_t* frameBuffer = renderer.getFrameBuffer();
+  if (!frameBuffer) {
+    return false;
+  }
+
+  // Free any existing buffer first
+  freeCoverBuffer();
+
+  const size_t bufferSize = GfxRenderer::getBufferSize();
+  coverBuffer = static_cast<uint8_t*>(malloc(bufferSize));
+  if (!coverBuffer) {
+    return false;
+  }
+
+  memcpy(coverBuffer, frameBuffer, bufferSize);
+  return true;
+}
+
+bool HomeActivity::restoreCoverBuffer() {
+  if (!coverBuffer) {
+    return false;
+  }
+
+  uint8_t* frameBuffer = renderer.getFrameBuffer();
+  if (!frameBuffer) {
+    return false;
+  }
+
+  const size_t bufferSize = GfxRenderer::getBufferSize();
+  memcpy(frameBuffer, coverBuffer, bufferSize);
+  return true;
+}
+
+void HomeActivity::freeCoverBuffer() {
+  if (coverBuffer) {
+    free(coverBuffer);
+    coverBuffer = nullptr;
+  }
+  coverBufferStored = false;
 }
 
 void HomeActivity::loop() {
@@ -138,8 +229,12 @@ void HomeActivity::displayTaskLoop() {
   }
 }
 
-void HomeActivity::render() const {
-  renderer.clearScreen();
+void HomeActivity::render() {
+  // If we have a stored cover buffer, restore it instead of clearing
+  const bool bufferRestored = coverBufferStored && restoreCoverBuffer();
+  if (!bufferRestored) {
+    renderer.clearScreen();
+  }
 
   const auto pageWidth = renderer.getScreenWidth();
   const auto pageHeight = renderer.getScreenHeight();
@@ -154,34 +249,101 @@ void HomeActivity::render() const {
   constexpr int bookY = 30;
   const bool bookSelected = hasContinueReading && selectorIndex == 0;
 
+  // Bookmark dimensions (used in multiple places)
+  const int bookmarkWidth = bookWidth / 8;
+  const int bookmarkHeight = bookHeight / 5;
+  const int bookmarkX = bookX + bookWidth - bookmarkWidth - 10;
+  const int bookmarkY = bookY + 5;
+
   // Draw book card regardless, fill with message based on `hasContinueReading`
   {
-    if (bookSelected) {
-      renderer.fillRect(bookX, bookY, bookWidth, bookHeight);
-    } else {
-      renderer.drawRect(bookX, bookY, bookWidth, bookHeight);
+    // Draw cover image as background if available (inside the box)
+    // Only load from SD on first render, then use stored buffer
+    if (hasContinueReading && hasCoverImage && !coverBmpPath.empty() && !coverRendered) {
+      // First time: load cover from SD and render
+      FsFile file;
+      if (SdMan.openFileForRead("HOME", coverBmpPath, file)) {
+        Bitmap bitmap(file);
+        if (bitmap.parseHeaders() == BmpReaderError::Ok) {
+          // Calculate position to center image within the book card
+          int coverX, coverY;
+
+          if (bitmap.getWidth() > bookWidth || bitmap.getHeight() > bookHeight) {
+            const float imgRatio = static_cast<float>(bitmap.getWidth()) / static_cast<float>(bitmap.getHeight());
+            const float boxRatio = static_cast<float>(bookWidth) / static_cast<float>(bookHeight);
+
+            if (imgRatio > boxRatio) {
+              coverX = bookX;
+              coverY = bookY + (bookHeight - static_cast<int>(bookWidth / imgRatio)) / 2;
+            } else {
+              coverX = bookX + (bookWidth - static_cast<int>(bookHeight * imgRatio)) / 2;
+              coverY = bookY;
+            }
+          } else {
+            coverX = bookX + (bookWidth - bitmap.getWidth()) / 2;
+            coverY = bookY + (bookHeight - bitmap.getHeight()) / 2;
+          }
+
+          // Draw the cover image centered within the book card
+          renderer.drawBitmap(bitmap, coverX, coverY, bookWidth, bookHeight);
+
+          // Draw border around the card
+          renderer.drawRect(bookX, bookY, bookWidth, bookHeight);
+
+          // No bookmark ribbon when cover is shown - it would just cover the art
+
+          // Store the buffer with cover image for fast navigation
+          coverBufferStored = storeCoverBuffer();
+          coverRendered = true;
+
+          // First render: if selected, draw selection indicators now
+          if (bookSelected) {
+            renderer.drawRect(bookX + 1, bookY + 1, bookWidth - 2, bookHeight - 2);
+            renderer.drawRect(bookX + 2, bookY + 2, bookWidth - 4, bookHeight - 4);
+          }
+        }
+        file.close();
+      }
+    } else if (!bufferRestored && !coverRendered) {
+      // No cover image: draw border or fill, plus bookmark as visual flair
+      if (bookSelected) {
+        renderer.fillRect(bookX, bookY, bookWidth, bookHeight);
+      } else {
+        renderer.drawRect(bookX, bookY, bookWidth, bookHeight);
+      }
+
+      // Draw bookmark ribbon when no cover image (visual decoration)
+      if (hasContinueReading) {
+        const int notchDepth = bookmarkHeight / 3;
+        const int centerX = bookmarkX + bookmarkWidth / 2;
+
+        const int xPoints[5] = {
+            bookmarkX,                  // top-left
+            bookmarkX + bookmarkWidth,  // top-right
+            bookmarkX + bookmarkWidth,  // bottom-right
+            centerX,                    // center notch point
+            bookmarkX                   // bottom-left
+        };
+        const int yPoints[5] = {
+            bookmarkY,                                // top-left
+            bookmarkY,                                // top-right
+            bookmarkY + bookmarkHeight,               // bottom-right
+            bookmarkY + bookmarkHeight - notchDepth,  // center notch point
+            bookmarkY + bookmarkHeight                // bottom-left
+        };
+
+        // Draw bookmark ribbon (inverted if selected)
+        renderer.fillPolygon(xPoints, yPoints, 5, !bookSelected);
+      }
     }
 
-    // Bookmark icon in the top-right corner of the card
-    const int bookmarkWidth = bookWidth / 8;
-    const int bookmarkHeight = bookHeight / 5;
-    const int bookmarkX = bookX + bookWidth - bookmarkWidth - 8;
-    constexpr int bookmarkY = bookY + 1;
-
-    // Main bookmark body (solid)
-    renderer.fillRect(bookmarkX, bookmarkY, bookmarkWidth, bookmarkHeight, !bookSelected);
-
-    // Carve out an inverted triangle notch at the bottom center to create angled points
-    const int notchHeight = bookmarkHeight / 2;  // depth of the notch
-    for (int i = 0; i < notchHeight; ++i) {
-      const int y = bookmarkY + bookmarkHeight - 1 - i;
-      const int xStart = bookmarkX + i;
-      const int width = bookmarkWidth - 2 * i;
-      if (width <= 0) {
-        break;
-      }
-      // Draw a horizontal strip in the opposite color to "cut" the notch
-      renderer.fillRect(xStart, y, width, 1, bookSelected);
+    // If buffer was restored, draw selection indicators if needed
+    if (bufferRestored && bookSelected && coverRendered) {
+      // Draw selection border (no bookmark inversion needed since cover has no bookmark)
+      renderer.drawRect(bookX + 1, bookY + 1, bookWidth - 2, bookHeight - 2);
+      renderer.drawRect(bookX + 2, bookY + 2, bookWidth - 4, bookHeight - 4);
+    } else if (!coverRendered && !bufferRestored) {
+      // Selection border already handled above in the no-cover case
     }
   }
 
@@ -218,18 +380,25 @@ void HomeActivity::render() const {
         lines.back().append("...");
 
         while (!lines.back().empty() && renderer.getTextWidth(UI_12_FONT_ID, lines.back().c_str()) > maxLineWidth) {
-          lines.back().resize(lines.back().size() - 5);
+          // Remove "..." first, then remove one UTF-8 char, then add "..." back
+          lines.back().resize(lines.back().size() - 3);  // Remove "..."
+          utf8RemoveLastChar(lines.back());
           lines.back().append("...");
         }
         break;
       }
 
       int wordWidth = renderer.getTextWidth(UI_12_FONT_ID, i.c_str());
-      while (wordWidth > maxLineWidth && i.size() > 5) {
-        // Word itself is too long, trim it
-        i.resize(i.size() - 5);
-        i.append("...");
-        wordWidth = renderer.getTextWidth(UI_12_FONT_ID, i.c_str());
+      while (wordWidth > maxLineWidth && !i.empty()) {
+        // Word itself is too long, trim it (UTF-8 safe)
+        utf8RemoveLastChar(i);
+        // Check if we have room for ellipsis
+        std::string withEllipsis = i + "...";
+        wordWidth = renderer.getTextWidth(UI_12_FONT_ID, withEllipsis.c_str());
+        if (wordWidth <= maxLineWidth) {
+          i = withEllipsis;
+          break;
+        }
       }
 
       int newLineWidth = renderer.getTextWidth(UI_12_FONT_ID, currentLine.c_str());
@@ -261,24 +430,85 @@ void HomeActivity::render() const {
     // Vertically center the title block within the card
     int titleYStart = bookY + (bookHeight - totalTextHeight) / 2;
 
+    // If cover image was rendered, draw white box behind title and author
+    if (coverRendered) {
+      constexpr int boxPadding = 8;
+      // Calculate the max text width for the box
+      int maxTextWidth = 0;
+      for (const auto& line : lines) {
+        const int lineWidth = renderer.getTextWidth(UI_12_FONT_ID, line.c_str());
+        if (lineWidth > maxTextWidth) {
+          maxTextWidth = lineWidth;
+        }
+      }
+      if (!lastBookAuthor.empty()) {
+        std::string trimmedAuthor = lastBookAuthor;
+        while (renderer.getTextWidth(UI_10_FONT_ID, trimmedAuthor.c_str()) > maxLineWidth && !trimmedAuthor.empty()) {
+          utf8RemoveLastChar(trimmedAuthor);
+        }
+        if (renderer.getTextWidth(UI_10_FONT_ID, trimmedAuthor.c_str()) <
+            renderer.getTextWidth(UI_10_FONT_ID, lastBookAuthor.c_str())) {
+          trimmedAuthor.append("...");
+        }
+        const int authorWidth = renderer.getTextWidth(UI_10_FONT_ID, trimmedAuthor.c_str());
+        if (authorWidth > maxTextWidth) {
+          maxTextWidth = authorWidth;
+        }
+      }
+
+      const int boxWidth = maxTextWidth + boxPadding * 2;
+      const int boxHeight = totalTextHeight + boxPadding * 2;
+      const int boxX = (pageWidth - boxWidth) / 2;
+      const int boxY = titleYStart - boxPadding;
+
+      // Draw white filled box
+      renderer.fillRect(boxX, boxY, boxWidth, boxHeight, false);
+      // Draw black border around the box
+      renderer.drawRect(boxX, boxY, boxWidth, boxHeight, true);
+    }
+
     for (const auto& line : lines) {
-      renderer.drawCenteredText(UI_12_FONT_ID, titleYStart, line.c_str(), !bookSelected);
+      renderer.drawCenteredText(UI_12_FONT_ID, titleYStart, line.c_str(), !bookSelected || coverRendered);
       titleYStart += renderer.getLineHeight(UI_12_FONT_ID);
     }
 
     if (!lastBookAuthor.empty()) {
       titleYStart += renderer.getLineHeight(UI_10_FONT_ID) / 2;
       std::string trimmedAuthor = lastBookAuthor;
-      // Trim author if too long
+      // Trim author if too long (UTF-8 safe)
+      bool wasTrimmed = false;
       while (renderer.getTextWidth(UI_10_FONT_ID, trimmedAuthor.c_str()) > maxLineWidth && !trimmedAuthor.empty()) {
-        trimmedAuthor.resize(trimmedAuthor.size() - 5);
+        utf8RemoveLastChar(trimmedAuthor);
+        wasTrimmed = true;
+      }
+      if (wasTrimmed && !trimmedAuthor.empty()) {
+        // Make room for ellipsis
+        while (renderer.getTextWidth(UI_10_FONT_ID, (trimmedAuthor + "...").c_str()) > maxLineWidth &&
+               !trimmedAuthor.empty()) {
+          utf8RemoveLastChar(trimmedAuthor);
+        }
         trimmedAuthor.append("...");
       }
-      renderer.drawCenteredText(UI_10_FONT_ID, titleYStart, trimmedAuthor.c_str(), !bookSelected);
+      renderer.drawCenteredText(UI_10_FONT_ID, titleYStart, trimmedAuthor.c_str(), !bookSelected || coverRendered);
     }
 
-    renderer.drawCenteredText(UI_10_FONT_ID, bookY + bookHeight - renderer.getLineHeight(UI_10_FONT_ID) * 3 / 2,
-                              "Continue Reading", !bookSelected);
+    // "Continue Reading" label at the bottom
+    const int continueY = bookY + bookHeight - renderer.getLineHeight(UI_10_FONT_ID) * 3 / 2;
+    if (coverRendered) {
+      // Draw white box behind "Continue Reading" text
+      const char* continueText = "Continue Reading";
+      const int continueTextWidth = renderer.getTextWidth(UI_10_FONT_ID, continueText);
+      constexpr int continuePadding = 6;
+      const int continueBoxWidth = continueTextWidth + continuePadding * 2;
+      const int continueBoxHeight = renderer.getLineHeight(UI_10_FONT_ID) + continuePadding;
+      const int continueBoxX = (pageWidth - continueBoxWidth) / 2;
+      const int continueBoxY = continueY - continuePadding / 2;
+      renderer.fillRect(continueBoxX, continueBoxY, continueBoxWidth, continueBoxHeight, false);
+      renderer.drawRect(continueBoxX, continueBoxY, continueBoxWidth, continueBoxHeight, true);
+      renderer.drawCenteredText(UI_10_FONT_ID, continueY, continueText, true);
+    } else {
+      renderer.drawCenteredText(UI_10_FONT_ID, continueY, "Continue Reading", !bookSelected);
+    }
   } else {
     // No book to continue reading
     const int y =

src/activities/home/HomeActivity.h

@@ -14,8 +14,13 @@ class HomeActivity final : public Activity {
   bool updateRequired = false;
   bool hasContinueReading = false;
   bool hasOpdsUrl = false;
+  bool hasCoverImage = false;
+  bool coverRendered = false;      // Track if cover has been rendered once
+  bool coverBufferStored = false;  // Track if cover buffer is stored
+  uint8_t* coverBuffer = nullptr;  // HomeActivity's own buffer for cover image
   std::string lastBookTitle;
   std::string lastBookAuthor;
+  std::string coverBmpPath;
   const std::function<void()> onContinueReading;
   const std::function<void()> onReaderOpen;
   const std::function<void()> onSettingsOpen;
@@ -24,8 +29,11 @@ class HomeActivity final : public Activity {
 
   static void taskTrampoline(void* param);
   [[noreturn]] void displayTaskLoop();
-  void render() const;
+  void render();
   int getMenuItemCount() const;
+  bool storeCoverBuffer();    // Store frame buffer for cover image
+  bool restoreCoverBuffer();  // Restore frame buffer from stored cover
+  void freeCoverBuffer();     // Free the stored cover buffer
 
  public:
   explicit HomeActivity(GfxRenderer& renderer, MappedInputManager& mappedInput,