static SkStream* extract_argb4444_data(const SkBitmap& bitmap,
const SkIRect& srcRect,
bool extractAlpha,
bool* isOpaque,
bool* isTransparent) {
SkStream* stream;
uint8_t* dst = NULL;
if (extractAlpha) {
const int alphaRowBytes = (srcRect.width() + 1) / 2;
stream = SkNEW_ARGS(SkMemoryStream,
(alphaRowBytes * srcRect.height()));
} else {
stream = SkNEW_ARGS(SkMemoryStream,
(get_uncompressed_size(bitmap, srcRect)));
}
dst = (uint8_t*)stream->getMemoryBase();
for (int y = srcRect.fTop; y < srcRect.fBottom; y++) {
uint16_t* src = bitmap.getAddr16(0, y);
int x;
for (x = srcRect.fLeft; x + 1 < srcRect.fRight; x += 2) {
if (extractAlpha) {
dst[0] = (SkGetPackedA4444(src[x]) << 4) |
SkGetPackedA4444(src[x + 1]);
*isOpaque &= dst[0] == SK_AlphaOPAQUE;
*isTransparent &= dst[0] == SK_AlphaTRANSPARENT;
dst++;
} else {
dst[0] = (SkGetPackedR4444(src[x]) << 4) |
SkGetPackedG4444(src[x]);
dst[1] = (SkGetPackedB4444(src[x]) << 4) |
SkGetPackedR4444(src[x + 1]);
dst[2] = (SkGetPackedG4444(src[x + 1]) << 4) |
SkGetPackedB4444(src[x + 1]);
dst += 3;
}
}
if (srcRect.width() & 1) {
if (extractAlpha) {
dst[0] = (SkGetPackedA4444(src[x]) << 4);
*isOpaque &= dst[0] == (SK_AlphaOPAQUE & 0xF0);
*isTransparent &= dst[0] == (SK_AlphaTRANSPARENT & 0xF0);
dst++;
} else {
dst[0] = (SkGetPackedR4444(src[x]) << 4) |
SkGetPackedG4444(src[x]);
dst[1] = (SkGetPackedB4444(src[x]) << 4);
dst += 2;
}
}
}
return stream;
}
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);
}
}
// returns 0..15
static unsigned color_dist4444(uint16_t c, unsigned r, unsigned g, unsigned b)
{
SkASSERT(r <= 0xF);
SkASSERT(g <= 0xF);
SkASSERT(b <= 0xF);
unsigned dr = SkAbs32(SkGetPackedR4444(c) - r);
unsigned dg = SkAbs32(SkGetPackedG4444(c) - g);
unsigned db = SkAbs32(SkGetPackedB4444(c) - b);
return SkMax32(dr, SkMax32(dg, db));
}
static void rgb2yuv_4444(uint8_t dst[], U16CPU c) {
int r = SkGetPackedR4444(c);
int g = SkGetPackedG4444(c);
int b = SkGetPackedB4444(c);
int y = ( CYR*r + CYG*g + CYB*b ) >> (CSHIFT - 4);
int u = ( CUR*r + CUG*g + CUB*b ) >> (CSHIFT - 4);
int v = ( CVR*r + CVG*g + CVB*b ) >> (CSHIFT - 4);
dst[0] = SkToU8(y);
dst[1] = SkToU8(u + 128);
dst[2] = SkToU8(v + 128);
}