Rotate images in rotated PDFs before sending them to OCR.

If a PDF page is marked as rotated, the images in that page are rotated
before being sent to OCR service.

Bug: 1469236
Change-Id: I82d8981df86f0d7224886765589ed10dec551338
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4735395
Commit-Queue: Ramin Halavati <rhalavati@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1180140}

pdf/pdfium/pdfium_page.cc

@@ -43,6 +43,7 @@
 #include "ui/gfx/geometry/vector2d.h"
 #include "ui/gfx/geometry/vector2d_f.h"
 #include "ui/gfx/range/range.h"
+#include "ui/gfx/skbitmap_operations.h"
 
 using printing::ConvertUnitFloat;
 using printing::kPixelsPerInch;
@@ -1322,8 +1323,27 @@ void PDFiumPage::CalculateImages() {
         kBGRA_8888_SkColorType, kOpaque_SkAlphaType);
     const size_t row_bytes = FPDFBitmap_GetStride(bitmap.get());
     SkPixmap pixels(info, FPDFBitmap_GetBuffer(bitmap.get()), row_bytes);
-    if (image.image_data.tryAllocPixels(info, row_bytes))
-      image.image_data.writePixels(pixels);
+    if (!image.image_data.tryAllocPixels(info, row_bytes)) {
+      continue;
+    }
+    image.image_data.writePixels(pixels);
+
+    SkBitmapOperations::RotationAmount rotation;
+    switch (FPDFPage_GetRotation(page)) {
+      case 0:
+        continue;
+      case 1:
+        rotation = SkBitmapOperations::RotationAmount::ROTATION_90_CW;
+        break;
+      case 2:
+        rotation = SkBitmapOperations::RotationAmount::ROTATION_180_CW;
+        break;
+      case 3:
+        rotation = SkBitmapOperations::RotationAmount::ROTATION_270_CW;
+        break;
+    }
+
+    image.image_data = SkBitmapOperations::Rotate(image.image_data, rotation);
   }
 }
 

pdf/pdfium/pdfium_page.h

@@ -231,6 +231,7 @@ class PDFiumPage {
   FRIEND_TEST_ALL_PREFIXES(PDFiumPageImageTest, CalculateImages);
   FRIEND_TEST_ALL_PREFIXES(PDFiumPageImageTest, ImageAltText);
   FRIEND_TEST_ALL_PREFIXES(PDFiumPageImageDataTest, ImageData);
+  FRIEND_TEST_ALL_PREFIXES(PDFiumPageImageDataTest, RotatedPageImageData);
   FRIEND_TEST_ALL_PREFIXES(PDFiumPageLinkTest, AnnotLinkGeneration);
   FRIEND_TEST_ALL_PREFIXES(PDFiumPageLinkTest, GetLinkTarget);
   FRIEND_TEST_ALL_PREFIXES(PDFiumPageLinkTest, GetUTF8LinkTarget);

pdf/pdfium/pdfium_page_unittest.cc

@@ -553,6 +553,23 @@ TEST_P(PDFiumPageImageDataTest, ImageData) {
   EXPECT_EQ(page.images_[1].image_data.height(), 50);
 }
 
+TEST_P(PDFiumPageImageDataTest, RotatedPageImageData) {
+  TestClient client;
+  std::unique_ptr<PDFiumEngine> engine =
+      InitializeEngine(&client, FILE_PATH_LITERAL("rotated_page.pdf"));
+  ASSERT_TRUE(engine);
+  ASSERT_EQ(1, engine->GetNumberOfPages());
+
+  PDFiumPage& page = GetPDFiumPageForTest(*engine, 0);
+  page.CalculateImages();
+  ASSERT_EQ(1u, page.images_.size());
+
+  // This page is rotated, therefore the extracted image size is 25x100 while
+  // the stored image is 100x25.
+  EXPECT_EQ(page.images_[0].image_data.width(), 25);
+  EXPECT_EQ(page.images_[0].image_data.height(), 100);
+}
+
 INSTANTIATE_TEST_SUITE_P(All, PDFiumPageImageDataTest, testing::Bool());
 
 using PDFiumPageTextTest = PDFiumTestBase;

pdf/test/data/rotated_page.in

@@ -0,0 +1,53 @@
+{{header}}
+{{object 1 0}} <<
+  /Type /Catalog
+  /Pages 2 0 R
+>>
+endobj
+{{object 2 0}} <<
+  /Type /Pages
+  /MediaBox [0 0 200 200]
+  /Count 1
+  /Kids [3 0 R]
+>>
+endobj
+{{object 3 0}} <<
+  /Type /Page
+  /Parent 2 0 R
+  /Contents 4 0 R
+  /Rotate 270
+  /Resources <<
+    /XObject <<
+      /Img 5 0 R
+    >>
+  >>
+>>
+endobj
+{{object 4 0}} <<
+  {{streamlen}}
+>>
+stream
+q
+30 -30 40 40 100 100 cm
+/Img Do
+Q
+endstream
+endobj
+{{object 5 0}} <<
+  /Type /XObject
+  /Subtype /Image
+  /Width 100
+  /Height 25
+  /BitsPerComponent 8
+  /ColorSpace /DeviceRGB
+  /Filter [/ASCIIHexDecode /FlateDecode]
+  {{streamlen}}
+>>
+stream
+789cedc2310d00000c03a07f2aaab3ea7bcf03842655555555555555f5bf01cc7818dc
+endstream
+endobj
+{{xref}}
+{{trailer}}
+{{startxref}}
+%%EOF