grab from latest android
git-svn-id: http://skia.googlecode.com/svn/trunk@27 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/images/SkImageDecoder_libico.cpp b/src/images/SkImageDecoder_libico.cpp
new file mode 100644
index 0000000..b179a6b
--- /dev/null
+++ b/src/images/SkImageDecoder_libico.cpp
@@ -0,0 +1,388 @@
+/* libs/graphics/images/SkImageDecoder_libico.cpp
+**
+** Copyright 2006, The Android Open Source Project
+**
+** Licensed under the Apache License, Version 2.0 (the "License");
+** you may not use this file except in compliance with the License.
+** You may obtain a copy of the License at
+**
+** http://www.apache.org/licenses/LICENSE-2.0
+**
+** Unless required by applicable law or agreed to in writing, software
+** distributed under the License is distributed on an "AS IS" BASIS,
+** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+** See the License for the specific language governing permissions and
+** limitations under the License.
+*/
+
+#include "SkImageDecoder.h"
+#include "SkStream.h"
+#include "SkColorPriv.h"
+#include "SkTypes.h"
+
+class SkICOImageDecoder : public SkImageDecoder {
+public:
+ SkICOImageDecoder();
+
+ virtual Format getFormat() const {
+ return kICO_Format;
+ }
+
+protected:
+ virtual bool onDecode(SkStream* stream, SkBitmap* bm,
+ SkBitmap::Config pref, Mode);
+};
+
+/////////////////////////////////////////////////////////////////////////////////////////
+
+//read bytes starting from the begin-th index in the buffer
+//read in Intel order, and return an integer
+
+#define readByte(buffer,begin) buffer[begin]
+#define read2Bytes(buffer,begin) buffer[begin]+(buffer[begin+1]<<8)
+#define read4Bytes(buffer,begin) buffer[begin]+(buffer[begin+1]<<8)+(buffer[begin+2]<<16)+(buffer[begin+3]<<24)
+
+/////////////////////////////////////////////////////////////////////////////////////////
+
+SkImageDecoder* SkImageDecoder_ICO_Factory(SkStream*);
+SkImageDecoder* SkImageDecoder_ICO_Factory(SkStream* stream)
+{
+ //i'm going to check if we basically have 0,0,1,0 (reserved = 0, type = 1)
+ //is that required and sufficient?
+ SkAutoMalloc autoMal(4);
+ unsigned char* buf = (unsigned char*)autoMal.get();
+ stream->read((void*)buf, 4);
+ int reserved = read2Bytes(buf, 0);
+ int type = read2Bytes(buf, 2);
+ if (reserved != 0 || type != 1) //it's not an ico
+ return NULL;
+ return SkNEW(SkICOImageDecoder);
+}
+
+/////////////////////////////////////////////////////////////////////////////////////////
+
+SkICOImageDecoder::SkICOImageDecoder()
+{
+}
+
+//helpers - my function pointer will call one of these, depending on the bitCount, each time through the inner loop
+static void editPixelBit1(const int pixelNo, const unsigned char* buf,
+ const int xorOffset, int& x, int y, const int w,
+ SkBitmap* bm, int alphaByte, int m, int shift, SkPMColor* colors);
+static void editPixelBit4(const int pixelNo, const unsigned char* buf,
+ const int xorOffset, int& x, int y, const int w,
+ SkBitmap* bm, int alphaByte, int m, int shift, SkPMColor* colors);
+static void editPixelBit8(const int pixelNo, const unsigned char* buf,
+ const int xorOffset, int& x, int y, const int w,
+ SkBitmap* bm, int alphaByte, int m, int shift, SkPMColor* colors);
+static void editPixelBit24(const int pixelNo, const unsigned char* buf,
+ const int xorOffset, int& x, int y, const int w,
+ SkBitmap* bm, int alphaByte, int m, int shift, SkPMColor* colors);
+static void editPixelBit32(const int pixelNo, const unsigned char* buf,
+ const int xorOffset, int& x, int y, const int w,
+ SkBitmap* bm, int alphaByte, int m, int shift, SkPMColor* colors);
+
+
+static int calculateRowBytesFor8888(int w, int bitCount)
+{
+ // Default rowBytes is w << 2 for kARGB_8888
+ // In the case of a 4 bit image with an odd width, we need to add some
+ // so we can go off the end of the drawn bitmap.
+ // Add 4 to ensure that it is still a multiple of 4.
+ if (4 == bitCount && (w & 0x1)) {
+ return (w + 1) << 2;
+ }
+ // Otherwise return 0, which will allow it to be calculated automatically.
+ return 0;
+}
+
+bool SkICOImageDecoder::onDecode(SkStream* stream, SkBitmap* bm,
+ SkBitmap::Config pref, Mode mode)
+{
+ size_t length = stream->read(NULL, 0);
+ SkAutoMalloc autoMal(length);
+ unsigned char* buf = (unsigned char*)autoMal.get();
+ if (stream->read((void*)buf, length) != length) {
+ return false;
+ }
+
+ //these should always be the same - should i use for error checking? - what about files that have some
+ //incorrect values, but still decode properly?
+ int reserved = read2Bytes(buf, 0); // 0
+ int type = read2Bytes(buf, 2); // 1
+ if (reserved != 0 || type != 1)
+ return false;
+ int count = read2Bytes(buf, 4);
+
+ //need to at least have enough space to hold the initial table of info
+ if (length < (size_t)(6 + count*16))
+ return false;
+
+ int choice;
+ Chooser* chooser = this->getChooser();
+ //FIXME:if no chooser, consider providing the largest color image
+ //what are the odds that the largest image would be monochrome?
+ if (NULL == chooser) {
+ choice = 0;
+ } else {
+ chooser->begin(count);
+ for (int i = 0; i < count; i++)
+ {
+ //need to find out the config, width, and height from the stream
+ int width = readByte(buf, 6 + i*16);
+ int height = readByte(buf, 7 + i*16);
+ int offset = read4Bytes(buf, 18 + i*16);
+ int bitCount = read2Bytes(buf, offset+14);
+ SkBitmap::Config c;
+ //currently only provide ARGB_8888_, but maybe we want kIndex8_Config for 1 and 4, and possibly 8?
+ //or maybe we'll determine this based on the provided config
+ switch (bitCount)
+ {
+ case 1:
+ case 4:
+ // In reality, at least for the moment, these will be decoded into kARGB_8888 bitmaps.
+ // However, this will be used to distinguish between the lower quality 1bpp and 4 bpp
+ // images and the higher quality images.
+ c = SkBitmap::kIndex8_Config;
+ break;
+ case 8:
+ case 24:
+ case 32:
+ c = SkBitmap::kARGB_8888_Config;
+ break;
+ default:
+ SkDEBUGF(("Image with %ibpp not supported\n", bitCount));
+ continue;
+ }
+ chooser->inspect(i, c, width, height);
+ }
+ choice = chooser->choose();
+ }
+
+ //you never know what the chooser is going to supply
+ if (choice >= count || choice < 0)
+ return false;
+
+ //skip ahead to the correct header
+ //commented out lines are not used, but if i switch to other read method, need to know how many to skip
+ //otherwise, they could be used for error checking
+ int w = readByte(buf, 6 + choice*16);
+ int h = readByte(buf, 7 + choice*16);
+ int colorCount = readByte(buf, 8 + choice*16);
+ //int reservedToo = readByte(buf, 9 + choice*16); //0
+ //int planes = read2Bytes(buf, 10 + choice*16); //1 - but often 0
+ //int fakeBitCount = read2Bytes(buf, 12 + choice*16); //should be real - usually 0
+ int size = read4Bytes(buf, 14 + choice*16); //matters?
+ int offset = read4Bytes(buf, 18 + choice*16);
+ if ((size_t)(offset + size) > length)
+ return false;
+ //int infoSize = read4Bytes(buf, offset); //40
+ //int width = read4Bytes(buf, offset+4); //should == w
+ //int height = read4Bytes(buf, offset+8); //should == 2*h
+ //int planesToo = read2Bytes(buf, offset+12); //should == 1 (does it?)
+ int bitCount = read2Bytes(buf, offset+14);
+
+ void (*placePixel)(const int pixelNo, const unsigned char* buf,
+ const int xorOffset, int& x, int y, const int w,
+ SkBitmap* bm, int alphaByte, int m, int shift, SkPMColor* colors) = NULL;
+ switch (bitCount)
+ {
+ case 1:
+ placePixel = &editPixelBit1;
+ colorCount = 2;
+ break;
+ case 4:
+ placePixel = &editPixelBit4;
+ colorCount = 16;
+ break;
+ case 8:
+ placePixel = &editPixelBit8;
+ colorCount = 256;
+ break;
+ case 24:
+ placePixel = &editPixelBit24;
+ colorCount = 0;
+ break;
+ case 32:
+ placePixel = &editPixelBit32;
+ colorCount = 0;
+ break;
+ default:
+ SkDEBUGF(("Decoding %ibpp is unimplemented\n", bitCount));
+ return false;
+ }
+
+ //these should all be zero, but perhaps are not - need to check
+ //int compression = read4Bytes(buf, offset+16); //0
+ //int imageSize = read4Bytes(buf, offset+20); //0 - sometimes has a value
+ //int xPixels = read4Bytes(buf, offset+24); //0
+ //int yPixels = read4Bytes(buf, offset+28); //0
+ //int colorsUsed = read4Bytes(buf, offset+32) //0 - might have an actual value though
+ //int colorsImportant = read4Bytes(buf, offset+36); //0
+
+ int begin = offset + 40;
+ //this array represents the colortable
+ //if i allow other types of bitmaps, it may actually be used as a part of the bitmap
+ SkPMColor* colors = NULL;
+ int blue, green, red;
+ if (colorCount)
+ {
+ colors = new SkPMColor[colorCount];
+ for (int j = 0; j < colorCount; j++)
+ {
+ //should this be a function - maybe a #define?
+ blue = readByte(buf, begin + 4*j);
+ green = readByte(buf, begin + 4*j + 1);
+ red = readByte(buf, begin + 4*j + 2);
+ colors[j] = SkPackARGB32(0xFF, red & 0xFF, green & 0xFF, blue & 0xFF);
+ }
+ }
+ int bitWidth = w*bitCount;
+ int test = bitWidth & 0x1F;
+ int mask = -(((test >> 4) | (test >> 3) | (test >> 2) | (test >> 1) | test) & 0x1); //either 0xFFFFFFFF or 0
+ int lineBitWidth = (bitWidth & 0xFFFFFFE0) + (0x20 & mask);
+ int lineWidth = lineBitWidth/bitCount;
+
+ int xorOffset = begin + colorCount*4; //beginning of the color bitmap
+ //other read method means we will just be here already
+ int andOffset = xorOffset + ((lineWidth*h*bitCount) >> 3);
+
+ /*int */test = w & 0x1F; //the low 5 bits - we are rounding up to the next 32 (2^5)
+ /*int */mask = -(((test >> 4) | (test >> 3) | (test >> 2) | (test >> 1) | test) & 0x1); //either 0xFFFFFFFF or 0
+ int andLineWidth = (w & 0xFFFFFFE0) + (0x20 & mask);
+ //if we allow different Configs, everything is the same til here
+ //change the config, and use different address getter, and place index vs color, and add the color table
+ //FIXME: what is the tradeoff in size?
+ //if the andbitmap (mask) is all zeroes, then we can easily do an index bitmap
+ //however, with small images with large colortables, maybe it's better to still do argb_8888
+
+ bm->setConfig(SkBitmap::kARGB_8888_Config, w, h, calculateRowBytesFor8888(w, bitCount));
+
+ if (SkImageDecoder::kDecodeBounds_Mode == mode) {
+ delete[] colors;
+ return true;
+ }
+
+ if (!this->allocPixelRef(bm, NULL))
+ {
+ delete[] colors;
+ return false;
+ }
+
+ SkAutoLockPixels alp(*bm);
+
+ for (int y = 0; y < h; y++)
+ {
+ for (int x = 0; x < w; x++)
+ {
+ //U32* address = bm->getAddr32(x, y);
+
+ //check the alpha bit first, but pass it along to the function to figure out how to deal with it
+ int andPixelNo = andLineWidth*(h-y-1)+x;
+ //only need to get a new alphaByte when x %8 == 0
+ //but that introduces an if and a mod - probably much slower
+ //that's ok, it's just a read of an array, not a stream
+ int alphaByte = readByte(buf, andOffset + (andPixelNo >> 3));
+ int shift = 7 - (andPixelNo & 0x7);
+ int m = 1 << shift;
+
+ int pixelNo = lineWidth*(h-y-1)+x;
+ placePixel(pixelNo, buf, xorOffset, x, y, w, bm, alphaByte, m, shift, colors);
+
+ }
+ }
+
+ delete [] colors;
+ //ensure we haven't read off the end?
+ //of course this doesn't help us if the andOffset was a lie...
+ //return andOffset + (andLineWidth >> 3) <= length;
+ return true;
+} //onDecode
+
+//function to place the pixel, determined by the bitCount
+static void editPixelBit1(const int pixelNo, const unsigned char* buf,
+ const int xorOffset, int& x, int y, const int w,
+ SkBitmap* bm, int alphaByte, int m, int shift, SkPMColor* colors)
+{
+ // note that this should be the same as/similar to the AND bitmap
+ SkPMColor* address = bm->getAddr32(x,y);
+ int byte = readByte(buf, xorOffset + (pixelNo >> 3));
+ int colorBit;
+ int alphaBit;
+ // Read all of the bits in this byte.
+ int i = x + 8;
+ // Pin to the width so we do not write outside the bounds of
+ // our color table.
+ i = i > w ? w : i;
+ // While loop to check all 8 bits individually.
+ while (x < i)
+ {
+
+ colorBit = (byte & m) >> shift;
+ alphaBit = (alphaByte & m) >> shift;
+ *address = (alphaBit-1)&(colors[colorBit]);
+ x++;
+ // setup for the next pixel
+ address = address + 1;
+ m = m >> 1;
+ shift -= 1;
+ }
+ x--;
+}
+static void editPixelBit4(const int pixelNo, const unsigned char* buf,
+ const int xorOffset, int& x, int y, const int w,
+ SkBitmap* bm, int alphaByte, int m, int shift, SkPMColor* colors)
+{
+ SkPMColor* address = bm->getAddr32(x, y);
+ int byte = readByte(buf, xorOffset + (pixelNo >> 1));
+ int pixel = (byte >> 4) & 0xF;
+ int alphaBit = (alphaByte & m) >> shift;
+ *address = (alphaBit-1)&(colors[pixel]);
+ x++;
+ //if w is odd, x may be the same as w, which means we are writing to an unused portion of the bitmap
+ //but that's okay, since i've added an extra rowByte for just this purpose
+ address = address + 1;
+ pixel = byte & 0xF;
+ m = m >> 1;
+ alphaBit = (alphaByte & m) >> (shift-1);
+ //speed up trick here
+ *address = (alphaBit-1)&(colors[pixel]);
+}
+
+static void editPixelBit8(const int pixelNo, const unsigned char* buf,
+ const int xorOffset, int& x, int y, const int w,
+ SkBitmap* bm, int alphaByte, int m, int shift, SkPMColor* colors)
+{
+ SkPMColor* address = bm->getAddr32(x, y);
+ int pixel = readByte(buf, xorOffset + pixelNo);
+ int alphaBit = (alphaByte & m) >> shift;
+ *address = (alphaBit-1)&(colors[pixel]);
+}
+
+static void editPixelBit24(const int pixelNo, const unsigned char* buf,
+ const int xorOffset, int& x, int y, const int w,
+ SkBitmap* bm, int alphaByte, int m, int shift, SkPMColor* colors)
+{
+ SkPMColor* address = bm->getAddr32(x, y);
+ int blue = readByte(buf, xorOffset + 3*pixelNo);
+ int green = readByte(buf, xorOffset + 3*pixelNo + 1);
+ int red = readByte(buf, xorOffset + 3*pixelNo + 2);
+ int alphaBit = (alphaByte & m) >> shift;
+ //alphaBit == 1 => alpha = 0
+ int alpha = (alphaBit-1) & 0xFF;
+ *address = SkPackARGB32(alpha, red & alpha, green & alpha, blue & alpha);
+}
+
+static void editPixelBit32(const int pixelNo, const unsigned char* buf,
+ const int xorOffset, int& x, int y, const int w,
+ SkBitmap* bm, int alphaByte, int m, int shift, SkPMColor* colors)
+{
+ SkPMColor* address = bm->getAddr32(x, y);
+ int blue = readByte(buf, xorOffset + 4*pixelNo);
+ int green = readByte(buf, xorOffset + 4*pixelNo + 1);
+ int red = readByte(buf, xorOffset + 4*pixelNo + 2);
+ int alphaBit = (alphaByte & m) >> shift;
+ int alpha = readByte(buf, xorOffset + 4*pixelNo + 3) & ((alphaBit-1)&0xFF);
+ *address = SkPackARGB32(alpha, red & alpha, green & alpha, blue & alpha);
+}
+