commit 83e0f1b1bb111c99d2f11d382b31caef0af5de10
author Hal Canary <halcanary@google.com> Thu Apr 05 16:58:41 2018 -0400
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Sat Apr 07 14:25:30 2018 +0000
tree 8ed18a789d4f8b72525ccd308af2a08e9ea409ef
parent c7695ff269a6ec7c4420d571d9077f2895166083

SkPDF: smarter Jpeg when libjpeg-turbo is present

The fallback code does not parse the color type for EXIF-only jpegs.
Since these exist in the wild, we need to find out if they are really
standard YUV or greyscale Jpegs and embed them in PDFs if they are.

BUG=chromium:801430
Change-Id: I93eaf8b8fc22b7169b2fce9520e022b72ad0bf81
Reviewed-on: https://skia-review.googlesource.com/118992
Commit-Queue: Hal Canary <halcanary@google.com>
Reviewed-by: Leon Scroggins <scroggo@google.com>

src/pdf/SkJpegInfo.cpp

diff --git a/src/pdf/SkJpegInfo.cpp b/src/pdf/SkJpegInfo.cpp
index 5e5ec79..df99de4 100644
--- a/src/pdf/SkJpegInfo.cpp
+++ b/src/pdf/SkJpegInfo.cpp
@@ -5,15 +5,16 @@
  * found in the LICENSE file.
  */
 
-#include "SkData.h"
 #include "SkJpegInfo.h"
 
+#ifndef SK_HAS_JPEG_LIBRARY
+
 namespace {
 class JpegSegment {
 public:
-    JpegSegment(const SkData* skdata)
-        : fData(static_cast<const char*>(skdata->data()))
-        , fSize(skdata->size())
+    JpegSegment(const void* data, size_t size)
+        : fData(static_cast<const char*>(data))
+        , fSize(size)
         , fOffset(0)
         , fLength(0) {}
     bool read() {
@@ -75,10 +76,13 @@
 };
 }  // namespace
 
-bool SkIsJFIF(const SkData* skdata, SkJFIFInfo* info) {
+bool SkGetJpegInfo(const void* data, size_t len,
+                   SkISize* size,
+                   SkEncodedInfo::Color* colorType,
+                   SkEncodedOrigin* orientation) {
     static const uint16_t kSOI = 0xFFD8;
     static const uint16_t kAPP0 = 0xFFE0;
-    JpegSegment segment(skdata);
+    JpegSegment segment(data, len);
     if (!segment.read() || segment.marker() != kSOI) {
         return false;  // not a JPEG
     }
@@ -106,14 +110,17 @@
     if (numberOfComponents != 1 && numberOfComponents != 3) {
         return false;  // Invalid JFIF
     }
-    if (info) {
-        info->fSize.set(JpegSegment::GetBigendianUint16(&segment.data()[3]),
-                        JpegSegment::GetBigendianUint16(&segment.data()[1]));
-        if (numberOfComponents == 3) {
-            info->fType = SkJFIFInfo::kYCbCr;
-        } else {
-            info->fType = SkJFIFInfo::kGrayscale;
-        }
+    if (size) {
+        *size = {JpegSegment::GetBigendianUint16(&segment.data()[3]),
+                 JpegSegment::GetBigendianUint16(&segment.data()[1])};
+    }
+    if (colorType) {
+        *colorType = numberOfComponents == 3 ? SkEncodedInfo::kYUV_Color
+                                             : SkEncodedInfo::kGray_Color;
+    }
+    if (orientation) {
+        *orientation = kTopLeft_SkEncodedOrigin;
     }
     return true;
 }
+#endif  // SK_HAS_JPEG_LIBRARY