[PDF] Add unpremultiply support and a GM (try4)
This is a resubmit of https://codereview.chromium.org/22831039 which was reverted because it causes issues on Windows (really, release builds). BUG=chromium:175548 R=edisonn@google.com Review URL: https://codereview.chromium.org/33493003 git-svn-id: http://skia.googlecode.com/svn/trunk@11928 2bbb7eff-a529-9590-31e7-b0007b416f81
This commit is contained in:
vandebo@chromium.org
parent
0794dcd2c0
commit
e66d376067
131
gm/bitmappremul.cpp
Normal file
131
gm/bitmappremul.cpp
Normal file
@ -0,0 +1,131 @@
|
||||
/*
|
||||
* Copyright 2013 Google Inc.
|
||||
*
|
||||
* Use of this source code is governed by a BSD-style license that can be
|
||||
* found in the LICENSE file.
|
||||
*/
|
||||
|
||||
#include "gm.h"
|
||||
#include "SkBitmap.h"
|
||||
#include "SkCanvas.h"
|
||||
#include "SkColorPriv.h"
|
||||
|
||||
/**
|
||||
* This GM checks that bitmap pixels are unpremultiplied before being exported
|
||||
* to other formats. If unpremultiplication is implemented properly, this
|
||||
* GM should come out completely white. If not, this GM looks like a row of two
|
||||
* greyscale gradients above a row of grey lines.
|
||||
* This tests both the ARGB4444 and ARGB8888 bitmap configurations.
|
||||
*/
|
||||
|
||||
static const int SLIDE_SIZE = 256;
|
||||
static const int PIXEL_SIZE_8888 = SLIDE_SIZE / 256;
|
||||
static const int PIXEL_SIZE_4444 = SLIDE_SIZE / 16;
|
||||
|
||||
static SkBitmap init_bitmap(SkBitmap::Config config) {
|
||||
SkBitmap bitmap;
|
||||
bitmap.setConfig(config, SLIDE_SIZE, SLIDE_SIZE);
|
||||
bitmap.allocPixels();
|
||||
bitmap.eraseColor(SK_ColorWHITE);
|
||||
return bitmap;
|
||||
}
|
||||
|
||||
static SkBitmap make_argb8888_gradient() {
|
||||
SkBitmap bitmap = init_bitmap(SkBitmap::kARGB_8888_Config);
|
||||
uint8_t rowColor = 0;
|
||||
for (int y = 0; y < SLIDE_SIZE; y++) {
|
||||
uint32_t* dst = bitmap.getAddr32(0, y);
|
||||
for (int x = 0; x < SLIDE_SIZE; x++) {
|
||||
dst[x] = SkPackARGB32(rowColor, rowColor,
|
||||
rowColor, rowColor);
|
||||
}
|
||||
if (y % PIXEL_SIZE_8888 == PIXEL_SIZE_8888 - 1) {
|
||||
rowColor++;
|
||||
}
|
||||
}
|
||||
return bitmap;
|
||||
}
|
||||
|
||||
static SkBitmap make_argb4444_gradient() {
|
||||
SkBitmap bitmap = init_bitmap(SkBitmap::kARGB_4444_Config);
|
||||
uint8_t rowColor = 0;
|
||||
for (int y = 0; y < SLIDE_SIZE; y++) {
|
||||
uint16_t* dst = bitmap.getAddr16(0, y);
|
||||
for (int x = 0; x < SLIDE_SIZE; x++) {
|
||||
dst[x] = SkPackARGB4444(rowColor, rowColor,
|
||||
rowColor, rowColor);
|
||||
}
|
||||
if (y % PIXEL_SIZE_4444 == PIXEL_SIZE_4444 - 1) {
|
||||
rowColor++;
|
||||
}
|
||||
}
|
||||
return bitmap;
|
||||
}
|
||||
|
||||
static SkBitmap make_argb8888_stripes() {
|
||||
SkBitmap bitmap = init_bitmap(SkBitmap::kARGB_8888_Config);
|
||||
uint8_t rowColor = 0;
|
||||
for (int y = 0; y < SLIDE_SIZE; y++) {
|
||||
uint32_t* dst = bitmap.getAddr32(0, y);
|
||||
for (int x = 0; x < SLIDE_SIZE; x++) {
|
||||
dst[x] = SkPackARGB32(rowColor, rowColor,
|
||||
rowColor, rowColor);
|
||||
}
|
||||
if (rowColor == 0) {
|
||||
rowColor = 255;
|
||||
} else {
|
||||
rowColor = 0;
|
||||
}
|
||||
}
|
||||
return bitmap;
|
||||
}
|
||||
|
||||
static SkBitmap make_argb4444_stripes() {
|
||||
SkBitmap bitmap = init_bitmap(SkBitmap::kARGB_4444_Config);
|
||||
uint8_t rowColor = 0;;
|
||||
for (int y = 0; y < SLIDE_SIZE; y++) {
|
||||
uint16_t* dst = bitmap.getAddr16(0, y);
|
||||
for (int x = 0; x < SLIDE_SIZE; x++) {
|
||||
dst[x] = SkPackARGB4444(rowColor, rowColor,
|
||||
rowColor, rowColor);
|
||||
}
|
||||
if (rowColor == 0) {
|
||||
rowColor = 15;
|
||||
} else {
|
||||
rowColor = 0;
|
||||
}
|
||||
}
|
||||
return bitmap;
|
||||
}
|
||||
|
||||
namespace skiagm {
|
||||
|
||||
class BitmapPremulGM : public GM {
|
||||
public:
|
||||
BitmapPremulGM() {
|
||||
this->setBGColor(SK_ColorWHITE);
|
||||
}
|
||||
|
||||
protected:
|
||||
SkString onShortName() SK_OVERRIDE {
|
||||
return SkString("bitmap_premul");
|
||||
}
|
||||
|
||||
virtual SkISize onISize() SK_OVERRIDE {
|
||||
return SkISize::Make(SLIDE_SIZE * 2, SLIDE_SIZE * 2);
|
||||
}
|
||||
|
||||
virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
|
||||
SkScalar slideSize = SkIntToScalar(SLIDE_SIZE);
|
||||
canvas->drawBitmap(make_argb8888_gradient(), 0, 0);
|
||||
canvas->drawBitmap(make_argb4444_gradient(), slideSize, 0);
|
||||
canvas->drawBitmap(make_argb8888_stripes(), 0, slideSize);
|
||||
canvas->drawBitmap(make_argb4444_stripes(), slideSize, slideSize);
|
||||
}
|
||||
|
||||
private:
|
||||
typedef GM INHERITED;
|
||||
};
|
||||
|
||||
DEF_GM( return new BitmapPremulGM; )
|
||||
}
|
||||
@ -15,6 +15,7 @@
|
||||
'../gm/bitmapcopy.cpp',
|
||||
'../gm/bitmapmatrix.cpp',
|
||||
'../gm/bitmapfilters.cpp',
|
||||
'../gm/bitmappremul.cpp',
|
||||
'../gm/bitmaprect.cpp',
|
||||
'../gm/bitmaprecttest.cpp',
|
||||
'../gm/bitmapscroll.cpp',
|
||||
|
||||
@ -336,6 +336,157 @@ static SkPDFArray* make_indexed_color_space(SkColorTable* table) {
|
||||
return result;
|
||||
}
|
||||
|
||||
/**
|
||||
* Removes the alpha component of an ARGB color (including unpremultiply) while
|
||||
* keeping the output in the same format as the input.
|
||||
*/
|
||||
static uint32_t remove_alpha_argb8888(uint32_t pmColor) {
|
||||
SkColor color = SkUnPreMultiply::PMColorToColor(pmColor);
|
||||
return SkPackARGB32NoCheck(SK_AlphaOPAQUE,
|
||||
SkColorGetR(color),
|
||||
SkColorGetG(color),
|
||||
SkColorGetB(color));
|
||||
}
|
||||
|
||||
static uint16_t remove_alpha_argb4444(uint16_t pmColor) {
|
||||
return SkPixel32ToPixel4444(
|
||||
remove_alpha_argb8888(SkPixel4444ToPixel32(pmColor)));
|
||||
}
|
||||
|
||||
static uint32_t get_argb8888_neighbor_avg_color(const SkBitmap& bitmap,
|
||||
int xOrig, int yOrig) {
|
||||
uint8_t count = 0;
|
||||
uint16_t r = 0;
|
||||
uint16_t g = 0;
|
||||
uint16_t b = 0;
|
||||
|
||||
for (int y = yOrig - 1; y <= yOrig + 1; y++) {
|
||||
if (y < 0 || y >= bitmap.height()) {
|
||||
continue;
|
||||
}
|
||||
uint32_t* src = bitmap.getAddr32(0, y);
|
||||
for (int x = xOrig - 1; x <= xOrig + 1; x++) {
|
||||
if (x < 0 || x >= bitmap.width()) {
|
||||
continue;
|
||||
}
|
||||
if (SkGetPackedA32(src[x]) != SK_AlphaTRANSPARENT) {
|
||||
uint32_t color = remove_alpha_argb8888(src[x]);
|
||||
r += SkGetPackedR32(color);
|
||||
g += SkGetPackedG32(color);
|
||||
b += SkGetPackedB32(color);
|
||||
count++;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (count == 0) {
|
||||
return SkPackARGB32NoCheck(SK_AlphaOPAQUE, 0, 0, 0);
|
||||
} else {
|
||||
return SkPackARGB32NoCheck(SK_AlphaOPAQUE,
|
||||
r / count, g / count, b / count);
|
||||
}
|
||||
}
|
||||
|
||||
static uint16_t get_argb4444_neighbor_avg_color(const SkBitmap& bitmap,
|
||||
int xOrig, int yOrig) {
|
||||
uint8_t count = 0;
|
||||
uint8_t r = 0;
|
||||
uint8_t g = 0;
|
||||
uint8_t b = 0;
|
||||
|
||||
for (int y = yOrig - 1; y <= yOrig + 1; y++) {
|
||||
if (y < 0 || y >= bitmap.height()) {
|
||||
continue;
|
||||
}
|
||||
uint16_t* src = bitmap.getAddr16(0, y);
|
||||
for (int x = xOrig - 1; x <= xOrig + 1; x++) {
|
||||
if (x < 0 || x >= bitmap.width()) {
|
||||
continue;
|
||||
}
|
||||
if ((SkGetPackedA4444(src[x]) & 0x0F) != SK_AlphaTRANSPARENT) {
|
||||
uint16_t color = remove_alpha_argb4444(src[x]);
|
||||
r += SkGetPackedR4444(color);
|
||||
g += SkGetPackedG4444(color);
|
||||
b += SkGetPackedB4444(color);
|
||||
count++;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (count == 0) {
|
||||
return SkPackARGB4444(SK_AlphaOPAQUE & 0x0F, 0, 0, 0);
|
||||
} else {
|
||||
return SkPackARGB4444(SK_AlphaOPAQUE & 0x0F,
|
||||
r / count, g / count, b / count);
|
||||
}
|
||||
}
|
||||
|
||||
static SkBitmap unpremultiply_bitmap(const SkBitmap& bitmap,
|
||||
const SkIRect& srcRect) {
|
||||
SkBitmap outBitmap;
|
||||
outBitmap.setConfig(bitmap.config(), srcRect.width(), srcRect.height());
|
||||
outBitmap.allocPixels();
|
||||
size_t dstRow = 0;
|
||||
|
||||
outBitmap.lockPixels();
|
||||
bitmap.lockPixels();
|
||||
switch (bitmap.config()) {
|
||||
case SkBitmap::kARGB_4444_Config: {
|
||||
for (int y = srcRect.fTop; y < srcRect.fBottom; y++) {
|
||||
uint16_t* dst = outBitmap.getAddr16(0, dstRow);
|
||||
uint16_t* src = bitmap.getAddr16(0, y);
|
||||
for (int x = srcRect.fLeft; x < srcRect.fRight; x++) {
|
||||
uint8_t a = SkGetPackedA4444(src[x]);
|
||||
// It is necessary to average the color component of
|
||||
// transparent pixels with their surrounding neighbors
|
||||
// since the PDF renderer may separately re-sample the
|
||||
// alpha and color channels when the image is not
|
||||
// displayed at its native resolution. Since an alpha of
|
||||
// zero gives no information about the color component,
|
||||
// the pathological case is a white image with sharp
|
||||
// transparency bounds - the color channel goes to black,
|
||||
// and the should-be-transparent pixels are rendered
|
||||
// as grey because of the separate soft mask and color
|
||||
// resizing.
|
||||
if (a == (SK_AlphaTRANSPARENT & 0x0F)) {
|
||||
*dst = get_argb4444_neighbor_avg_color(bitmap, x, y);
|
||||
} else {
|
||||
*dst = remove_alpha_argb4444(src[x]);
|
||||
}
|
||||
dst++;
|
||||
}
|
||||
dstRow++;
|
||||
}
|
||||
break;
|
||||
}
|
||||
case SkBitmap::kARGB_8888_Config: {
|
||||
for (int y = srcRect.fTop; y < srcRect.fBottom; y++) {
|
||||
uint32_t* dst = outBitmap.getAddr32(0, dstRow);
|
||||
uint32_t* src = bitmap.getAddr32(0, y);
|
||||
for (int x = srcRect.fLeft; x < srcRect.fRight; x++) {
|
||||
uint8_t a = SkGetPackedA32(src[x]);
|
||||
if (a == SK_AlphaTRANSPARENT) {
|
||||
*dst = get_argb8888_neighbor_avg_color(bitmap, x, y);
|
||||
} else {
|
||||
*dst = remove_alpha_argb8888(src[x]);
|
||||
}
|
||||
dst++;
|
||||
}
|
||||
dstRow++;
|
||||
}
|
||||
break;
|
||||
}
|
||||
default:
|
||||
SkASSERT(false);
|
||||
}
|
||||
bitmap.unlockPixels();
|
||||
outBitmap.unlockPixels();
|
||||
|
||||
outBitmap.setImmutable();
|
||||
|
||||
return outBitmap;
|
||||
}
|
||||
|
||||
// static
|
||||
SkPDFImage* SkPDFImage::CreateImage(const SkBitmap& bitmap,
|
||||
const SkIRect& srcRect,
|
||||
@ -358,8 +509,17 @@ SkPDFImage* SkPDFImage::CreateImage(const SkBitmap& bitmap,
|
||||
return NULL;
|
||||
}
|
||||
|
||||
SkPDFImage* image = SkNEW_ARGS(SkPDFImage, (NULL, bitmap,
|
||||
false, srcRect, encoder));
|
||||
SkPDFImage* image;
|
||||
SkBitmap::Config config = bitmap.config();
|
||||
if (alphaData.get() != NULL && (config == SkBitmap::kARGB_8888_Config ||
|
||||
config == SkBitmap::kARGB_4444_Config)) {
|
||||
SkBitmap unpremulBitmap = unpremultiply_bitmap(bitmap, srcRect);
|
||||
image = SkNEW_ARGS(SkPDFImage, (NULL, unpremulBitmap, false,
|
||||
SkIRect::MakeWH(srcRect.width(), srcRect.height()),
|
||||
encoder));
|
||||
} else {
|
||||
image = SkNEW_ARGS(SkPDFImage, (NULL, bitmap, false, srcRect, encoder));
|
||||
}
|
||||
if (alphaData.get() != NULL) {
|
||||
SkAutoTUnref<SkPDFImage> mask(
|
||||
SkNEW_ARGS(SkPDFImage, (alphaData.get(), bitmap,
|
||||
|
||||
Loading…
Reference in New Issue
Block a user