commit d9dfa18372119c8e1318125d2075fa80e0819094
author edisonn@google.com <edisonn@google.com@2bbb7eff-a529-9590-31e7-b0007b416f81> Wed Apr 24 13:01:01 2013 +0000
committer edisonn@google.com <edisonn@google.com@2bbb7eff-a529-9590-31e7-b0007b416f81> Wed Apr 24 13:01:01 2013 +0000
tree 1a4a321c54972e86cf5bec762839145a01f028dd
parent 6238c57c8dd8ddc14ca778017a0c43ba773b744f

Encode images with DCTDecode (JPEG) in PDFs if it makes sense. Fallback to FlateDecode (zip) if it makes sense. Otherewise include uncompressed stream.
This change will reduce the size of PDFs to 50% (in the case of the existing SKPs, we reduce the total size of PDFs from 105MB to 50MB) 
Review URL: https://codereview.appspot.com/7068055

git-svn-id: http://skia.googlecode.com/svn/trunk@8835 2bbb7eff-a529-9590-31e7-b0007b416f81

tools/render_pdfs_main.cpp

diff --git a/tools/render_pdfs_main.cpp b/tools/render_pdfs_main.cpp
index 1ac02d3..96666ac 100644
--- a/tools/render_pdfs_main.cpp
+++ b/tools/render_pdfs_main.cpp
@@ -9,6 +9,7 @@
 #include "SkDevice.h"
 #include "SkGraphics.h"
 #include "SkImageDecoder.h"
+#include "SkImageEncoder.h"
 #include "SkOSFile.h"
 #include "SkPicture.h"
 #include "SkStream.h"
@@ -38,7 +39,7 @@
     SkDebugf("SKP to PDF rendering tool\n");
     SkDebugf("\n"
 "Usage: \n"
-"     %s <input>... -w <outputDir> \n"
+"     %s <input>... [-w <outputDir>] [--jpegQuality N] \n"
 , argv0);
     SkDebugf("\n\n");
     SkDebugf(
@@ -47,6 +48,12 @@
     SkDebugf(
 "     outputDir: directory to write the rendered pdfs.\n\n");
     SkDebugf("\n");
+        SkDebugf(
+"     jpegQuality N: encodes images in JPEG at quality level N, which can\n"
+"                    be in range 0-100).\n"
+"                    N = -1 will disable JPEG compression.\n"
+"                    Default is N = 100, maximum quality.\n\n");
+    SkDebugf("\n");
 }
 
 /** Replaces the extension of a file.
@@ -71,6 +78,33 @@
     return false;
 }
 
+int gJpegQuality = 100;
+static bool encode_to_dct_stream(SkWStream* stream, const SkBitmap& bitmap, const SkIRect& rect) {
+    if (gJpegQuality == -1) return false;
+
+        SkIRect bitmapBounds;
+        SkBitmap subset;
+        const SkBitmap* bitmapToUse = &bitmap;
+        bitmap.getBounds(&bitmapBounds);
+        if (rect != bitmapBounds) {
+            SkAssertResult(bitmap.extractSubset(&subset, rect));
+            bitmapToUse = &subset;
+        }
+    
+#if defined(SK_BUILD_FOR_MAC)
+        // Workaround bug #1043 where bitmaps with referenced pixels cause
+        // CGImageDestinationFinalize to crash
+        SkBitmap copy;
+        bitmapToUse->deepCopyTo(&copy, bitmapToUse->config());
+        bitmapToUse = &copy;
+#endif
+
+    return SkImageEncoder::EncodeStream(stream,
+                                        *bitmapToUse,
+                                        SkImageEncoder::kJPEG_Type,
+                                        gJpegQuality);
+}
+
 /** Builds the output filename. path = dir/name, and it replaces expected
  * .skp extension with .pdf extention.
  * @param path Output filename.
@@ -200,6 +234,19 @@
                 exit(-1);
             }
             *outputDir = SkString(*argv);
+        } else if (0 == strcmp(*argv, "--jpegQuality")) {
+            ++argv;
+            if (argv >= stop) {
+                SkDebugf("Missing argument for --jpegQuality\n");
+                usage(argv0);
+                exit(-1);
+            }
+            gJpegQuality = atoi(*argv);
+            if (gJpegQuality < -1 || gJpegQuality > 100) {
+                SkDebugf("Invalid argument for --jpegQuality\n");
+                usage(argv0);
+                exit(-1);            
+            }
         } else {
             inputs->push_back(SkString(*argv));
         }
@@ -217,7 +264,7 @@
     SkTArray<SkString> inputs;
 
     SkAutoTUnref<sk_tools::PdfRenderer>
-        renderer(SkNEW(sk_tools::SimplePdfRenderer));
+        renderer(SkNEW_ARGS(sk_tools::SimplePdfRenderer, (encode_to_dct_stream)));
     SkASSERT(renderer.get());
 
     SkString outputDir;