[PDF] Support image alpha channel plus a couple small fixes.
Fix bug in rendering paths with cubic segments.
Only compress data if the compressed size is smaller than the uncompressed size.
Review URL: http://codereview.appspot.com/4079048
git-svn-id: http://skia.googlecode.com/svn/trunk@747 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/pdf/SkPDFImage.h b/include/pdf/SkPDFImage.h
index 48d6398..9b4e4f9 100644
--- a/include/pdf/SkPDFImage.h
+++ b/include/pdf/SkPDFImage.h
@@ -36,19 +36,45 @@
// and settings used from the paint to canonicalize image objects.
class SkPDFImage : public SkPDFObject {
public:
- /** Create a PDF image XObject. Entries for the image properties are
- * automatically added to the stream dictionary.
- * @param bitmap The image to use.
- * @param paint Used to calculate alpha, masks, etc.
+ /** Create a new Image XObject to represent the passed bitmap.
+ * @param bitmap The image to encode.
+ * @param srcRect The rectangle to cut out of bitmap.
+ * @param paint Used to calculate alpha, masks, etc.
+ * @return The image XObject or NUll if there is nothing to draw for
+ * the given parameters.
*/
- SkPDFImage(const SkBitmap& bitmap, const SkIRect& srcRect,
- const SkPaint& paint);
+ static SkPDFImage* CreateImage(const SkBitmap& bitmap,
+ const SkIRect& srcRect,
+ const SkPaint& paint);
+
virtual ~SkPDFImage();
+ /** Add a Soft Mask (alpha or shape channel) to the image.
+ * @param mask A gray scale image representing the mask.
+ */
+ void addSMask(SkPDFImage* mask);
+
// The SkPDFObject interface.
virtual void emitObject(SkWStream* stream, SkPDFCatalog* catalog,
bool indirect);
virtual size_t getOutputSize(SkPDFCatalog* catalog, bool indirect);
+ virtual void getResources(SkTDArray<SkPDFObject*>* resourceList);
+
+private:
+ SkRefPtr<SkPDFStream> fStream;
+ SkTDArray<SkPDFObject*> fResources;
+
+ /** Create a PDF image XObject. Entries for the image properties are
+ * automatically added to the stream dictionary.
+ * @param imageData The final raw bits representing the image.
+ * @param bitmap The image parameters to use (Config, etc).
+ * @param srcRect The clipping applied to bitmap before generating
+ * imageData.
+ * @param alpha Is this the alpha channel of the bitmap.
+ * @param paint Used to calculate alpha, masks, etc.
+ */
+ SkPDFImage(SkStream* imageData, const SkBitmap& bitmap,
+ const SkIRect& srcRect, bool alpha, const SkPaint& paint);
/** Add the value to the stream dictionary with the given key.
* @param key The key for this dictionary entry.
@@ -61,9 +87,6 @@
* @param value The value for this dictionary entry.
*/
void insert(const char key[], SkPDFObject* value);
-
-private:
- SkRefPtr<SkPDFStream> fStream;
};
#endif
diff --git a/src/pdf/SkPDFDevice.cpp b/src/pdf/SkPDFDevice.cpp
index b98e4af..d3a15a8 100644
--- a/src/pdf/SkPDFDevice.cpp
+++ b/src/pdf/SkPDFDevice.cpp
@@ -702,6 +702,7 @@
fContent.appendScalar(dstX);
fContent.append(" ");
fContent.appendScalar(dstY);
+ fContent.append(" ");
fContent.append(cmd);
}
@@ -817,6 +818,10 @@
if (srcRect && !subset.intersect(*srcRect))
return;
+ SkPDFImage* image = SkPDFImage::CreateImage(bitmap, subset, paint);
+ if (!image)
+ return;
+
SkMatrix scaled;
// Adjust for origin flip.
scaled.setScale(1, -1);
@@ -826,7 +831,6 @@
scaled.postConcat(matrix);
SkMatrix curTransform = setTransform(scaled);
- SkPDFImage* image = new SkPDFImage(bitmap, subset, paint);
fXObjectResources.push(image); // Transfer reference.
fContent.append("/X");
fContent.appendS32(fXObjectResources.count() - 1);
diff --git a/src/pdf/SkPDFGraphicState.cpp b/src/pdf/SkPDFGraphicState.cpp
index 286468b..8cc8314 100644
--- a/src/pdf/SkPDFGraphicState.cpp
+++ b/src/pdf/SkPDFGraphicState.cpp
@@ -83,9 +83,8 @@
typeName->unref(); // SkRefPtr and new both took a reference.
insert("Type", typeName.get());
- SkScalar maxAlpha = SkIntToScalar(0xFF);
SkRefPtr<SkPDFScalar> alpha =
- new SkPDFScalar(SkColorGetA(fPaint.getColor())/maxAlpha);
+ new SkPDFScalar(fPaint.getAlpha() * SkScalarInvert(0xFF));
alpha->unref(); // SkRefPtr and new both took a reference.
insert("CA", alpha.get());
insert("ca", alpha.get());
diff --git a/src/pdf/SkPDFImage.cpp b/src/pdf/SkPDFImage.cpp
index 51bf8ae..6c35f5a 100644
--- a/src/pdf/SkPDFImage.cpp
+++ b/src/pdf/SkPDFImage.cpp
@@ -29,16 +29,19 @@
namespace {
-SkMemoryStream* extractImageData(const SkBitmap& bitmap,
- const SkIRect& srcRect) {
- SkMemoryStream* result = NULL;
+void extractImageData(const SkBitmap& bitmap, const SkIRect& srcRect,
+ SkStream** imageData, SkStream** alphaData) {
+ SkMemoryStream* image = NULL;
+ SkMemoryStream* alpha = NULL;
+ bool hasAlpha = false;
+ bool isTransparent = false;
bitmap.lockPixels();
switch (bitmap.getConfig()) {
case SkBitmap::kIndex8_Config: {
const int rowBytes = srcRect.width();
- result = new SkMemoryStream(rowBytes * srcRect.height());
- uint8_t* dst = (uint8_t*)result->getMemoryBase();
+ image = new SkMemoryStream(rowBytes * srcRect.height());
+ uint8_t* dst = (uint8_t*)image->getMemoryBase();
for (int y = srcRect.fTop; y < srcRect.fBottom; y++) {
memcpy(dst, bitmap.getAddr8(srcRect.fLeft, y), rowBytes);
dst += rowBytes;
@@ -47,8 +50,8 @@
}
case SkBitmap::kRLE_Index8_Config: {
const int rowBytes = srcRect.width();
- result = new SkMemoryStream(rowBytes * srcRect.height());
- uint8_t* dst = (uint8_t*)result->getMemoryBase();
+ image = new SkMemoryStream(rowBytes * srcRect.height());
+ uint8_t* dst = (uint8_t*)image->getMemoryBase();
const SkBitmap::RLEPixels* rle =
(const SkBitmap::RLEPixels*)bitmap.getPixels();
for (int y = srcRect.fTop; y < srcRect.fBottom; y++) {
@@ -59,9 +62,13 @@
break;
}
case SkBitmap::kARGB_4444_Config: {
+ isTransparent = true;
const int rowBytes = (srcRect.width() * 3 + 1) / 2;
- result = new SkMemoryStream(rowBytes * srcRect.height());
- uint8_t* dst = (uint8_t*)result->getMemoryBase();
+ const int alphaRowBytes = (srcRect.width() + 1) / 2;
+ image = new SkMemoryStream(rowBytes * srcRect.height());
+ alpha = new SkMemoryStream(alphaRowBytes * srcRect.height());
+ uint8_t* dst = (uint8_t*)image->getMemoryBase();
+ uint8_t* alphaDst = (uint8_t*)alpha->getMemoryBase();
for (int y = srcRect.fTop; y < srcRect.fBottom; y++) {
uint16_t* src = bitmap.getAddr16(0, y);
int x;
@@ -73,19 +80,31 @@
dst[2] = (SkGetPackedG4444(src[x + 1]) << 4) |
SkGetPackedB4444(src[x + 1]);
dst += 3;
+ alphaDst[0] = (SkGetPackedA4444(src[x]) << 4) |
+ SkGetPackedA4444(src[x + 1]);
+ if (alphaDst[0] != 0xFF)
+ hasAlpha = true;
+ if (alphaDst[0])
+ isTransparent = false;
+ alphaDst++;
}
if (srcRect.width() & 1) {
dst[0] = (SkGetPackedR4444(src[x]) << 4) |
SkGetPackedG4444(src[x]);
dst[1] = (SkGetPackedB4444(src[x]) << 4);
+ alphaDst[0] = (SkGetPackedA4444(src[x]) << 4);
+ if (alphaDst[0] != 0xF0)
+ hasAlpha = true;
+ if (alphaDst[0] & 0xF0)
+ isTransparent = false;
}
}
break;
}
case SkBitmap::kRGB_565_Config: {
const int rowBytes = srcRect.width() * 3;
- result = new SkMemoryStream(rowBytes * srcRect.height());
- uint8_t* dst = (uint8_t*)result->getMemoryBase();
+ image = new SkMemoryStream(rowBytes * srcRect.height());
+ uint8_t* dst = (uint8_t*)image->getMemoryBase();
for (int y = srcRect.fTop; y < srcRect.fBottom; y++) {
uint16_t* src = bitmap.getAddr16(0, y);
for (int x = srcRect.fLeft; x < srcRect.fRight; x++) {
@@ -98,9 +117,12 @@
break;
}
case SkBitmap::kARGB_8888_Config: {
+ isTransparent = true;
const int rowBytes = srcRect.width() * 3;
- result = new SkMemoryStream(rowBytes * srcRect.height());
- uint8_t* dst = (uint8_t*)result->getMemoryBase();
+ image = new SkMemoryStream(rowBytes * srcRect.height());
+ alpha = new SkMemoryStream(srcRect.width() * srcRect.height());
+ uint8_t* dst = (uint8_t*)image->getMemoryBase();
+ uint8_t* alphaDst = (uint8_t*)alpha->getMemoryBase();
for (int y = srcRect.fTop; y < srcRect.fBottom; y++) {
uint32_t* src = bitmap.getAddr32(0, y);
for (int x = srcRect.fLeft; x < srcRect.fRight; x++) {
@@ -108,6 +130,71 @@
dst[1] = SkGetPackedG32(src[x]);
dst[2] = SkGetPackedB32(src[x]);
dst += 3;
+ alphaDst[0] = SkGetPackedA32(src[x]);
+ if (alphaDst[0] != 0xFF)
+ hasAlpha = true;
+ if (alphaDst[0])
+ isTransparent = false;
+ alphaDst++;
+ }
+ }
+ break;
+ }
+ case SkBitmap::kA1_Config: {
+ isTransparent = true;
+ image = new SkMemoryStream(1);
+ ((uint8_t*)image->getMemoryBase())[0] = 0;
+
+ const int alphaRowBytes = (srcRect.width() + 7) / 8;
+ alpha = new SkMemoryStream(alphaRowBytes * srcRect.height());
+ uint8_t* alphaDst = (uint8_t*)alpha->getMemoryBase();
+ int offset1 = srcRect.fLeft % 8;
+ int offset2 = 8 - offset1;
+ for (int y = srcRect.fTop; y < srcRect.fBottom; y++) {
+ uint8_t* src = bitmap.getAddr1(0, y);
+ // This may read up to one byte after src, but the potentially
+ // invalid bits are never used for computation.
+ for (int x = srcRect.fLeft; x < srcRect.fRight; x += 8) {
+ if (offset1) {
+ alphaDst[0] = src[x / 8] << offset1 |
+ src[x / 8 + 1] >> offset2;
+ } else {
+ alphaDst[0] = src[x / 8];
+ }
+ if (x + 7 < srcRect.fRight && alphaDst[0] != 0xFF)
+ hasAlpha = true;
+ if (x + 7 < srcRect.fRight && alphaDst[0])
+ isTransparent = false;
+ alphaDst++;
+ }
+ // Calculate the mask of bits we're interested in within the
+ // last byte of alphaDst.
+ // width mod 8 == 1 -> 0x80 ... width mod 8 == 7 -> 0xFE
+ uint8_t mask = ~((1 << (8 - (srcRect.width() % 8))) - 1);
+ if (srcRect.width() % 8 && (alphaDst[-1] & mask) != mask)
+ hasAlpha = true;
+ if (srcRect.width() % 8 && (alphaDst[-1] & mask))
+ isTransparent = false;
+ }
+ break;
+ }
+ case SkBitmap::kA8_Config: {
+ isTransparent = true;
+ image = new SkMemoryStream(1);
+ ((uint8_t*)image->getMemoryBase())[0] = 0;
+
+ const int alphaRowBytes = srcRect.width();
+ alpha = new SkMemoryStream(alphaRowBytes * srcRect.height());
+ uint8_t* alphaDst = (uint8_t*)alpha->getMemoryBase();
+ for (int y = srcRect.fTop; y < srcRect.fBottom; y++) {
+ uint8_t* src = bitmap.getAddr8(0, y);
+ for (int x = srcRect.fLeft; x < srcRect.fRight; x++) {
+ alphaDst[0] = src[x];
+ if (alphaDst[0] != 0xFF)
+ hasAlpha = true;
+ if (alphaDst[0])
+ isTransparent = false;
+ alphaDst++;
}
}
break;
@@ -116,7 +203,18 @@
SkASSERT(false);
}
bitmap.unlockPixels();
- return result;
+
+ if (isTransparent) {
+ SkSafeUnref(image);
+ } else {
+ *imageData = image;
+ }
+
+ if (isTransparent || !hasAlpha) {
+ SkSafeUnref(alpha);
+ } else {
+ *alphaData = alpha;
+ }
}
SkPDFArray* makeIndexedColorSpace(SkColorTable* table) {
@@ -153,20 +251,78 @@
}; // namespace
-SkPDFImage::SkPDFImage(const SkBitmap& bitmap, const SkIRect& srcRect,
+// static
+SkPDFImage* SkPDFImage::CreateImage(const SkBitmap& bitmap,
+ const SkIRect& srcRect,
+ const SkPaint& paint) {
+ if (bitmap.getConfig() == SkBitmap::kNo_Config)
+ return NULL;
+
+ SkStream* imageData = NULL;
+ SkStream* alphaData = NULL;
+ extractImageData(bitmap, srcRect, &imageData, &alphaData);
+ SkAutoUnref unrefImageData(imageData);
+ SkAutoUnref unrefAlphaData(alphaData);
+ if (!imageData) {
+ SkASSERT(!alphaData);
+ return NULL;
+ }
+
+ SkPDFImage* image =
+ new SkPDFImage(imageData, bitmap, srcRect, false, paint);
+
+ if (alphaData != NULL) {
+ SkRefPtr<SkPDFImage> alphaImage =
+ new SkPDFImage(alphaData, bitmap, srcRect, true, paint);
+ alphaImage->unref(); // SkRefPtr and new both took a reference.
+ image->addSMask(alphaImage.get());
+ }
+ return image;
+}
+
+SkPDFImage::~SkPDFImage() {
+ fResources.unrefAll();
+}
+
+void SkPDFImage::addSMask(SkPDFImage* mask) {
+ fResources.push(mask);
+ mask->ref();
+
+ SkRefPtr<SkPDFObjRef> maskRef = new SkPDFObjRef(mask);
+ maskRef->unref(); // SkRefPtr and new both took a reference.
+ insert("SMask", maskRef.get());
+}
+
+void SkPDFImage::emitObject(SkWStream* stream, SkPDFCatalog* catalog,
+ bool indirect) {
+ if (indirect)
+ return emitIndirectObject(stream, catalog);
+
+ fStream->emitObject(stream, catalog, indirect);
+}
+
+size_t SkPDFImage::getOutputSize(SkPDFCatalog* catalog, bool indirect) {
+ if (indirect)
+ return getIndirectOutputSize(catalog);
+
+ return fStream->getOutputSize(catalog, indirect);
+}
+
+void SkPDFImage::getResources(SkTDArray<SkPDFObject*>* resourceList) {
+ if (fResources.count()) {
+ resourceList->setReserve(resourceList->count() + fResources.count());
+ for (int i = 0; i < fResources.count(); i++) {
+ resourceList->push(fResources[i]);
+ fResources[i]->ref();
+ fResources[i]->getResources(resourceList);
+ }
+ }
+}
+
+SkPDFImage::SkPDFImage(SkStream* imageData, const SkBitmap& bitmap,
+ const SkIRect& srcRect, bool doingAlpha,
const SkPaint& paint) {
- SkBitmap::Config config = bitmap.getConfig();
-
- // TODO(vandebo) Handle alpha and alpha only images correctly.
- SkASSERT(config == SkBitmap::kRGB_565_Config ||
- config == SkBitmap::kARGB_4444_Config ||
- config == SkBitmap::kARGB_8888_Config ||
- config == SkBitmap::kIndex8_Config ||
- config == SkBitmap::kRLE_Index8_Config);
-
- SkMemoryStream* image_data = extractImageData(bitmap, srcRect);
- SkAutoUnref image_data_unref(image_data);
- fStream = new SkPDFStream(image_data);
+ fStream = new SkPDFStream(imageData);
fStream->unref(); // SkRefPtr and new both took a reference.
SkRefPtr<SkPDFName> typeValue = new SkPDFName("XObject");
@@ -177,17 +333,31 @@
subTypeValue->unref(); // SkRefPtr and new both took a reference.
insert("Subtype", subTypeValue.get());
- SkRefPtr<SkPDFInt> widthValue = new SkPDFInt(srcRect.width());
+ SkBitmap::Config config = bitmap.getConfig();
+ bool alphaOnly = (config == SkBitmap::kA1_Config ||
+ config == SkBitmap::kA8_Config);
+
+ SkRefPtr<SkPDFInt> widthValue;
+ SkRefPtr<SkPDFInt> heightValue;
+ if (!doingAlpha && alphaOnly) {
+ // For alpha only images, we stretch a single pixel of black for
+ // the color/shape part.
+ widthValue = new SkPDFInt(1);
+ heightValue = widthValue.get();
+ } else {
+ widthValue = new SkPDFInt(srcRect.width());
+ heightValue = new SkPDFInt(srcRect.height());
+ heightValue->unref(); // SkRefPtr and new both took a reference.
+ }
widthValue->unref(); // SkRefPtr and new both took a reference.
insert("Width", widthValue.get());
-
- SkRefPtr<SkPDFInt> heightValue = new SkPDFInt(srcRect.height());
- heightValue->unref(); // SkRefPtr and new both took a reference.
insert("Height", heightValue.get());
// if (!image mask) {
SkRefPtr<SkPDFObject> colorSpaceValue;
- if (config == SkBitmap::kIndex8_Config ||
+ if (doingAlpha || alphaOnly) {
+ colorSpaceValue = new SkPDFName("DeviceGray");
+ } else if (config == SkBitmap::kIndex8_Config ||
config == SkBitmap::kRLE_Index8_Config) {
colorSpaceValue = makeIndexedColorSpace(bitmap.getColorTable());
} else {
@@ -197,14 +367,11 @@
insert("ColorSpace", colorSpaceValue.get());
// }
- int bitsPerComp = bitmap.bytesPerPixel() * 2;
- if (bitsPerComp == 0) {
- SkASSERT(config == SkBitmap::kA1_Config);
+ int bitsPerComp = 8;
+ if (config == SkBitmap::kARGB_4444_Config)
+ bitsPerComp = 4;
+ else if (doingAlpha && config == SkBitmap::kA1_Config)
bitsPerComp = 1;
- } else if (bitsPerComp == 2 ||
- (bitsPerComp == 4 && config == SkBitmap::kRGB_565_Config)) {
- bitsPerComp = 8;
- }
SkRefPtr<SkPDFInt> bitsPerCompValue = new SkPDFInt(bitsPerComp);
bitsPerCompValue->unref(); // SkRefPtr and new both took a reference.
insert("BitsPerComponent", bitsPerCompValue.get());
@@ -229,23 +396,6 @@
}
}
-SkPDFImage::~SkPDFImage() {}
-
-void SkPDFImage::emitObject(SkWStream* stream, SkPDFCatalog* catalog,
- bool indirect) {
- if (indirect)
- return emitIndirectObject(stream, catalog);
-
- fStream->emitObject(stream, catalog, indirect);
-}
-
-size_t SkPDFImage::getOutputSize(SkPDFCatalog* catalog, bool indirect) {
- if (indirect)
- return getIndirectOutputSize(catalog);
-
- return fStream->getOutputSize(catalog, indirect);
-}
-
void SkPDFImage::insert(SkPDFName* key, SkPDFObject* value) {
fStream->insert(key, value);
}
diff --git a/src/pdf/SkPDFStream.cpp b/src/pdf/SkPDFStream.cpp
index 6947ae4..cbba068 100644
--- a/src/pdf/SkPDFStream.cpp
+++ b/src/pdf/SkPDFStream.cpp
@@ -20,14 +20,18 @@
#include "SkStream.h"
SkPDFStream::SkPDFStream(SkStream* stream) {
- if (SkFlate::HaveFlate()) {
+ if (SkFlate::HaveFlate())
SkAssertResult(SkFlate::Deflate(stream, &fCompressedData));
+
+ if (SkFlate::HaveFlate() &&
+ fCompressedData.getOffset() < stream->getLength()) {
fLength = fCompressedData.getOffset();
SkRefPtr<SkPDFName> flateFilter = new SkPDFName("FlateDecode");
flateFilter->unref(); // SkRefPtr and new both took a reference.
fDict.insert("Filter", flateFilter.get());
} else {
+ fCompressedData.reset();
fPlainData = stream;
fLength = fPlainData->getLength();
}