/*
**
** Copyright 2008, 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.
*/
#define LOG_TAG "FakeCamera"
#include <utils/Log.h>
#include <string.h>
#include <stdlib.h>
#include <utils/String8.h>
#include "FakeCamera.h"
namespace android {
// TODO: All this rgb to yuv should probably be in a util class.
// TODO: I think something is wrong in this class because the shadow is kBlue
// and the square color should alternate between kRed and kGreen. However on the
// emulator screen these are all shades of gray. Y seems ok but the U and V are
// probably not.
static int tables_initialized = 0;
uint8_t *gYTable, *gCbTable, *gCrTable;
static int
clamp(int x)
{
if (x > 255) return 255;
if (x < 0) return 0;
return x;
}
/* the equation used by the video code to translate YUV to RGB looks like this
*
* Y = (Y0 - 16)*k0
* Cb = Cb0 - 128
* Cr = Cr0 - 128
*
* G = ( Y - k1*Cr - k2*Cb )
* R = ( Y + k3*Cr )
* B = ( Y + k4*Cb )
*
*/
static const double k0 = 1.164;
static const double k1 = 0.813;
static const double k2 = 0.391;
static const double k3 = 1.596;
static const double k4 = 2.018;
/* let's try to extract the value of Y
*
* G + k1/k3*R + k2/k4*B = Y*( 1 + k1/k3 + k2/k4 )
*
* Y = ( G + k1/k3*R + k2/k4*B ) / (1 + k1/k3 + k2/k4)
* Y0 = ( G0 + k1/k3*R0 + k2/k4*B0 ) / ((1 + k1/k3 + k2/k4)*k0) + 16
*
* let define:
* kYr = k1/k3
* kYb = k2/k4
* kYy = k0 * ( 1 + kYr + kYb )
*
* we have:
* Y = ( G + kYr*R + kYb*B )
* Y0 = clamp[ Y/kYy + 16 ]
*/
static const double kYr = k1/k3;
static const double kYb = k2/k4;
static const double kYy = k0*( 1. + kYr + kYb );
static void
initYtab( void )
{
const int imax = (int)( (kYr + kYb)*(31 << 2) + (61 << 3) + 0.1 );
int i;
gYTable = (uint8_t *)malloc(imax);
for(i=0; i<imax; i++) {
int x = (int)(i/kYy + 16.5);
if (x < 16) x = 16;
else if (x > 235) x = 235;
gYTable[i] = (uint8_t) x;
}
}
/*
* the source is RGB565, so adjust for 8-bit range of input values:
*
* G = (pixels >> 3) & 0xFC;
* R = (pixels >> 8) & 0xF8;
* B = (pixels & 0x1f) << 3;
*
* R2 = (pixels >> 11) R = R2*8
* B2 = (pixels & 0x1f) B = B2*8
*
* kYr*R = kYr2*R2 => kYr2 = kYr*8
* kYb*B = kYb2*B2 => kYb2 = kYb*8
*
* we want to use integer multiplications:
*
* SHIFT1 = 9
*
* (ALPHA*R2) >> SHIFT1 == R*kYr => ALPHA = kYr*8*(1 << SHIFT1)
*
* ALPHA = kYr*(1 << (SHIFT1+3))
* BETA = kYb*(1 << (SHIFT1+3))
*/
static const int SHIFT1 = 9;
static const int ALPHA = (int)( kYr*(1 << (SHIFT1+3)) + 0.5 );
static const int BETA = (int)( kYb*(1 << (SHIFT1+3)) + 0.5 );
/*
* now let's try to get the values of Cb and Cr
*
* R-B = (k3*Cr - k4*Cb)
*
* k3*Cr = k4*Cb + (R-B)
* k4*Cb = k3*Cr - (R-B)
*
* R-G = (k1+k3)*Cr + k2*Cb
* = (k1+k3)*Cr + k2/k4*(k3*Cr - (R-B)/k0)
* = (k1 + k3 + k2*k3/k4)*Cr - k2/k4*(R-B)
*
* kRr*Cr = (R-G) + kYb*(R-B)
*
* Cr = ((R-G) + kYb*(R-B))/kRr
* Cr0 = clamp(Cr + 128)
*/
static const double kRr = (k1 + k3 + k2*k3/k4);
static void
initCrtab( void )
{
uint8_t *pTable;
int i;
gCrTable = (uint8_t *)malloc(768*2);
pTable = gCrTable + 384;
for(i=-384; i<384; i++)
pTable[i] = (uint8_t) clamp( i/kRr + 128.5 );
}
/*
* B-G = (k2 + k4)*Cb + k1*Cr
* = (k2 + k4)*Cb + k1/k3*(k4*Cb + (R-B))
* = (k2 + k4 + k1*k4/k3)*Cb + k1/k3*(R-B)
*
* kBb*Cb = (B-G) - kYr*(R-B)
*
* Cb = ((B-G) - kYr*(R-B))/kBb
* Cb0 = clamp(Cb + 128)
*
*/
static const double kBb = (k2 + k4 + k1*k4/k3);
static void
initCbtab( void )
{
uint8_t *pTable;
int i;
gCbTable = (uint8_t *)malloc(768*2);
pTable = gCbTable + 384;
for(i=-384; i<384; i++)
pTable[i] = (uint8_t) clamp( i/kBb + 128.5 );
}
/*
* SHIFT2 = 16
*
* DELTA = kYb*(1 << SHIFT2)
* GAMMA = kYr*(1 << SHIFT2)
*/
static const int SHIFT2 = 16;
static const int DELTA = kYb*(1 << SHIFT2);
static const int GAMMA = kYr*(1 << SHIFT2);
int32_t ccrgb16toyuv_wo_colorkey(uint8_t *rgb16, uint8_t *yuv420,
uint32_t *param, uint8_t *table[])
{
uint16_t *inputRGB = (uint16_t*)rgb16;
uint8_t *outYUV = yuv420;
int32_t width_dst = param[0];
int32_t height_dst = param[1];
int32_t pitch_dst = param[2];
int32_t mheight_dst = param[3];
int32_t pitch_src = param[4];
uint8_t *y_tab = table[0];
uint8_t *cb_tab = table[1];
uint8_t *cr_tab = table[2];
int32_t size16 = pitch_dst*mheight_dst;
int32_t i,j,count;
int32_t ilimit,jlimit;
uint8_t *tempY,*tempU,*tempV;
uint16_t pixels;
int tmp;
uint32_t temp;
tempY = outYUV;
tempU = outYUV + (height_dst * pitch_dst);
tempV = tempU + 1;
jlimit = height_dst;
ilimit = width_dst;
for(j=0; j<jlimit; j+=1)
{
for (i=0; i<ilimit; i+=2)
{
int32_t G_ds = 0, B_ds = 0, R_ds = 0;
uint8_t y0, y1, u, v;
pixels = inputRGB[i];
temp = (BETA*(pixels & 0x001F) + ALPHA*(pixels>>11) );
y0 = y_tab[(temp>>SHIFT1) + ((pixels>>3) & 0x00FC)];
G_ds += (pixels>>1) & 0x03E0;
B_ds += (pixels<<5) & 0x03E0;
R_ds += (pixels>>6) & 0x03E0;
pixels = inputRGB[i+1];
temp = (BETA*(pixels & 0x001F) + ALPHA*(pixels>>11) );
y1 = y_tab[(temp>>SHIFT1) + ((pixels>>3) & 0x00FC)];
G_ds += (pixels>>1) & 0x03E0;
B_ds += (pixels<<5) & 0x03E0;
R_ds += (pixels>>6) & 0x03E0;
R_ds >>= 1;
B_ds >>= 1;
G_ds >>= 1;
tmp = R_ds - B_ds;
u = cb_tab[(((B_ds-G_ds)<<SHIFT2) - GAMMA*tmp)>>(SHIFT2+2)];
v = cr_tab[(((R_ds-G_ds)<<SHIFT2) + DELTA*tmp)>>(SHIFT2+2)];
tempY[0] = y0;
tempY[1] = y1;
tempY += 2;
if ((j&1) == 0) {
tempU[0] = u;
tempV[0] = v;
tempU += 2;
tempV += 2;
}
}
inputRGB += pitch_src;
}
return 1;
}
#define min(a,b) ((a)<(b)?(a):(b))
#define max(a,b) ((a)>(b)?(a):(b))
static void convert_rgb16_to_yuv420(uint8_t *rgb, uint8_t *yuv, int width, int height)
{
if (!tables_initialized) {
initYtab();
initCrtab();
initCbtab();
tables_initialized = 1;
}
uint32_t param[6];
param[0] = (uint32_t) width;
param[1] = (uint32_t) height;
param[2] = (uint32_t) width;
param[3] = (uint32_t) height;
param[4] = (uint32_t) width;
param[5] = (uint32_t) 0;
uint8_t *table[3];
table[0] = gYTable;
table[1] = gCbTable + 384;
table[2] = gCrTable + 384;
ccrgb16toyuv_wo_colorkey(rgb, yuv, param, table);
}
const int FakeCamera::kRed;
const int FakeCamera::kGreen;
const int FakeCamera::kBlue;
FakeCamera::FakeCamera(int width, int height)
: mTmpRgb16Buffer(0)
{
setSize(width, height);
}
FakeCamera::~FakeCamera()
{
delete[] mTmpRgb16Buffer;
}
void FakeCamera::setSize(int width, int height)
{
mWidth = width;
mHeight = height;
mCounter = 0;
mCheckX = 0;
mCheckY = 0;
// This will cause it to be reallocated on the next call
// to getNextFrameAsYuv420().
delete[] mTmpRgb16Buffer;
mTmpRgb16Buffer = 0;
}
void FakeCamera::getNextFrameAsRgb565(uint16_t *buffer)
{
int size = mWidth / 10;
drawCheckerboard(buffer, size);
int x = ((mCounter*3)&255);
if(x>128) x = 255 - x;
int y = ((mCounter*5)&255);
if(y>128) y = 255 - y;
drawSquare(buffer, x*size/32, y*size/32, (size*5)>>1, (mCounter&0x100)?kRed:kGreen, kBlue);
mCounter++;
}
void FakeCamera::getNextFrameAsYuv420(uint8_t *buffer)
{
if (mTmpRgb16Buffer == 0)
mTmpRgb16Buffer = new uint16_t[mWidth * mHeight];
getNextFrameAsRgb565(mTmpRgb16Buffer);
convert_rgb16_to_yuv420((uint8_t*)mTmpRgb16Buffer, buffer, mWidth, mHeight);
}
void FakeCamera::drawSquare(uint16_t *dst, int x, int y, int size, int color, int shadow)
{
int square_xstop, square_ystop, shadow_xstop, shadow_ystop;
square_xstop = min(mWidth, x+size);
square_ystop = min(mHeight, y+size);
shadow_xstop = min(mWidth, x+size+(size/4));
shadow_ystop = min(mHeight, y+size+(size/4));
// Do the shadow.
uint16_t *sh = &dst[(y+(size/4))*mWidth];
for (int j = y + (size/4); j < shadow_ystop; j++) {
for (int i = x + (size/4); i < shadow_xstop; i++) {
sh[i] &= shadow;
}
sh += mWidth;
}
// Draw the square.
uint16_t *sq = &dst[y*mWidth];
for (int j = y; j < square_ystop; j++) {
for (int i = x; i < square_xstop; i++) {
sq[i] = color;
}
sq += mWidth;
}
}
void FakeCamera::drawCheckerboard(uint16_t *dst, int size)
{
bool black = true;
if((mCheckX/size)&1)
black = false;
if((mCheckY/size)&1)
black = !black;
int county = mCheckY%size;
int checkxremainder = mCheckX%size;
for(int y=0;y<mHeight;y++) {
int countx = checkxremainder;
bool current = black;
for(int x=0;x<mWidth;x++) {
dst[y*mWidth+x] = current?0:0xffff;
if(countx++ >= size) {
countx=0;
current = !current;
}
}
if(county++ >= size) {
county=0;
black = !black;
}
}
mCheckX += 3;
mCheckY++;
}
void FakeCamera::dump(int fd) const
{
const size_t SIZE = 256;
char buffer[SIZE];
String8 result;
snprintf(buffer, 255, " width x height (%d x %d), counter (%d), check x-y coordinate(%d, %d)\n", mWidth, mHeight, mCounter, mCheckX, mCheckY);
result.append(buffer);
::write(fd, result.string(), result.size());
}
}; // namespace android