#import "XeeYUVImage.h"



static void XeeYUVImageReadPixel(uint8_t *row,int x,int pixelsize,uint8_t *dest);
static void XeeBuildYUVConversionTables();



@implementation XeeYUVImage

-(id)initWithWidth:(int)pixelwidth height:(int)pixelheight
{
	if(self=[super init])
	{
		if([self allocWithWidth:pixelwidth height:pixelheight]) return self;
		[self release];
	}

	return nil;
}



-(void)setData:(uint8_t *)pixeldata freeData:(BOOL)willfree width:(int)pixelwidth height:(int)pixelheight bytesPerRow:(int)bprow
{
	#ifdef __BIG_ENDIAN__
	[super setData:pixeldata freeData:willfree width:pixelwidth height:pixelheight
	bytesPerPixel:2 bytesPerRow:bprow premultiplied:NO
	glInternalFormat:GL_RGB8 glFormat:GL_YCBCR_422_APPLE glType:GL_UNSIGNED_SHORT_8_8_REV_APPLE];
	#else
	[super setData:pixeldata freeData:willfree width:pixelwidth height:pixelheight
	bytesPerPixel:2 bytesPerRow:bprow premultiplied:NO
	glInternalFormat:GL_RGB8 glFormat:GL_YCBCR_422_APPLE glType:GL_UNSIGNED_SHORT_8_8_APPLE];
	#endif
}

-(BOOL)allocWithWidth:(int)pixelwidth height:(int)pixelheight
{
	int bprow=(2*pixelwidth+2)&~3;
	void *newdata=malloc(pixelheight*bprow);

	if(newdata)
	{
		uint32_t *ptr=(uint32_t *)newdata;
		#ifdef __BIG_ENDIAN__
		for(int i=0;i<pixelheight*bprow/4;i++) *ptr++=0x7f007f00;
		#else
		for(int i=0;i<pixelheight*bprow/4;i++) *ptr++=0x007f007f;
		#endif

		[self setData:newdata freeData:YES width:pixelwidth height:pixelheight bytesPerRow:bprow];
		return YES;
	}
	return NO;
}

-(void)fixYUVGamma
{
	static const unsigned char gammatable[256]=
	{
		0x00,0x00,0x01,0x01,0x02,0x02,0x03,0x03,0x04,0x04,0x05,0x05,0x06,0x07,0x07,0x08,
		0x09,0x09,0x0a,0x0b,0x0b,0x0c,0x0d,0x0d,0x0e,0x0f,0x10,0x10,0x11,0x12,0x13,0x13,
		0x14,0x15,0x16,0x17,0x17,0x18,0x19,0x1a,0x1b,0x1b,0x1c,0x1d,0x1e,0x1f,0x1f,0x20,
		0x21,0x22,0x23,0x24,0x25,0x25,0x26,0x27,0x28,0x29,0x2a,0x2b,0x2c,0x2c,0x2d,0x2e,
		0x2f,0x30,0x31,0x32,0x33,0x34,0x35,0x35,0x36,0x37,0x38,0x39,0x3a,0x3b,0x3c,0x3d,
		0x3e,0x3f,0x40,0x41,0x42,0x43,0x44,0x45,0x45,0x46,0x47,0x48,0x49,0x4a,0x4b,0x4c,
		0x4d,0x4e,0x4f,0x50,0x51,0x52,0x53,0x54,0x55,0x56,0x57,0x58,0x59,0x5a,0x5b,0x5c,
		0x5d,0x5e,0x5f,0x60,0x61,0x62,0x63,0x64,0x65,0x67,0x68,0x69,0x6a,0x6b,0x6c,0x6d,
		0x6e,0x6f,0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7b,0x7c,0x7d,0x7e,
		0x7f,0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x89,0x8a,0x8b,0x8c,0x8d,0x8e,0x8f,
		0x90,0x91,0x92,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0x9b,0x9c,0x9e,0x9f,0xa0,0xa1,
		0xa2,0xa3,0xa4,0xa5,0xa7,0xa8,0xa9,0xaa,0xab,0xac,0xad,0xaf,0xb0,0xb1,0xb2,0xb3,
		0xb4,0xb5,0xb7,0xb8,0xb9,0xba,0xbb,0xbc,0xbd,0xbf,0xc0,0xc1,0xc2,0xc3,0xc4,0xc6,
		0xc7,0xc8,0xc9,0xca,0xcb,0xcd,0xce,0xcf,0xd0,0xd1,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,
		0xda,0xdb,0xdc,0xdd,0xde,0xe0,0xe1,0xe2,0xe3,0xe4,0xe6,0xe7,0xe8,0xe9,0xea,0xec,
		0xed,0xee,0xef,0xf0,0xf2,0xf3,0xf4,0xf5,0xf6,0xf8,0xf9,0xfa,0xfb,0xfd,0xfe,0xff,
	};

	for(int y=0;y<height;y++)
	{
		int n=width;
		unsigned char *ptr=(unsigned char *)data+y*bytesperrow+1;

		while(n--)
		{
			*ptr=gammatable[*ptr];
			ptr+=2;
		}
	}
}

-(int)bitsPerComponentForCGImage { return 8; }

-(int)bytesPerPixelForCGImage { return 3; }

-(CGColorSpaceRef)createColorSpaceForCGImage { return CGColorSpaceCreateDeviceRGB(); }

-(int)bitmapInfoForCGImage { return 0; }

-(XeeReadPixelFunction)readPixelFunctionForCGImage
{
	static BOOL tables_built=NO;
	if(!tables_built)
	{
		XeeBuildYUVConversionTables();
		tables_built=YES;
	}

	return XeeYUVImageReadPixel;
}

@end



static int cr_r_tab[256];
static int cb_b_tab[256];
static int cr_g_tab[256];
static int cb_g_tab[256];
static uint8_t range_table[256*3],*range_limit;

#define ONE_HALF (1<<15)
#define FIX(x) ((int)((x)*(1<<16)+0.5))

static void XeeBuildYUVConversionTables()
{
	for(int i=0;i<256;i++)
	{
		range_table[i]=0;
		range_table[i+256]=i;
		range_table[i+512]=255;

		int x=i-128;
		cr_r_tab[i]=(int)(FIX(1.40200)*x+ONE_HALF)>>16;
		cb_b_tab[i]=(int)(FIX(1.77200)*x+ONE_HALF)>>16;
		cr_g_tab[i]=-FIX(0.71414)*x;
		cb_g_tab[i]=-FIX(0.34414)*x+ONE_HALF;
	}

	range_limit=range_table+256;
}

static void XeeYUVImageReadPixel(uint8_t *row,int x,int pixelsize,uint8_t *dest)
{
	uint8_t y=row[2*x|1];
	uint8_t cb=row[2*x&~2];
	uint8_t cr=row[2*x|2];

	dest[0]=range_limit[y+cr_r_tab[cr]];
	dest[1]=range_limit[y+((cb_g_tab[cb]+cr_g_tab[cr])>>16)];
	dest[2]=range_limit[y+cb_b_tab[cb]];
}
