/*

# RGB <-> YUV conversion routines
#             (C) 2008 Hans de Goede <hdegoede@redhat.com>

# RGB565 conversion routines
#             (C) 2009 Mauro Carvalho Chehab <mchehab@redhat.com>

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

#include <string.h>
#include "libv4lconvert-priv.h"

#define RGB2Y(r, g, b, y) \
	(y) = ((8453 * (r) + 16594 * (g) + 3223 * (b) + 524288) >> 15)

#define RGB2UV(r, g, b, u, v) 	\
	do {			\
		(u) = ((-4878 * (r) - 9578 * (g) + 14456 * (b) + 4210688) >> 15); \
		(v) = ((14456 * (r) - 12105 * (g) - 2351 * (b) + 4210688) >> 15); \
	} while (0)

void v4lconvert_rgb24_to_yuv420(const unsigned char *src, unsigned char *dest,
		const struct v4l2_format *src_fmt, int bgr, int yvu)
{
	int x, y;
	unsigned char *udest, *vdest;

	/* Y */
	for (y = 0; y < src_fmt->fmt.pix.height; y++) {
		for (x = 0; x < src_fmt->fmt.pix.width; x++) {
			if (bgr)
				RGB2Y(src[2], src[1], src[0], *dest++);
			else
				RGB2Y(src[0], src[1], src[2], *dest++);
			src += 3;
		}
		src += src_fmt->fmt.pix.bytesperline - 3 * src_fmt->fmt.pix.width;
	}
	src -= src_fmt->fmt.pix.height * src_fmt->fmt.pix.bytesperline;

	/* U + V */
	if (yvu) {
		vdest = dest;
		udest = dest + src_fmt->fmt.pix.width * src_fmt->fmt.pix.height / 4;
	} else {
		udest = dest;
		vdest = dest + src_fmt->fmt.pix.width * src_fmt->fmt.pix.height / 4;
	}

	for (y = 0; y < src_fmt->fmt.pix.height / 2; y++) {
		for (x = 0; x < src_fmt->fmt.pix.width / 2; x++) {
			int avg_src[3];

			avg_src[0] = (src[0] + src[3] + src[src_fmt->fmt.pix.bytesperline] +
					src[src_fmt->fmt.pix.bytesperline + 3]) / 4;
			avg_src[1] = (src[1] + src[4] + src[src_fmt->fmt.pix.bytesperline + 1] +
					src[src_fmt->fmt.pix.bytesperline + 4]) / 4;
			avg_src[2] = (src[2] + src[5] + src[src_fmt->fmt.pix.bytesperline + 2] +
					src[src_fmt->fmt.pix.bytesperline + 5]) / 4;
			if (bgr)
				RGB2UV(avg_src[2], avg_src[1], avg_src[0], *udest++, *vdest++);
			else
				RGB2UV(avg_src[0], avg_src[1], avg_src[2], *udest++, *vdest++);
			src += 6;
		}
		src += 2 * src_fmt->fmt.pix.bytesperline - 3 * src_fmt->fmt.pix.width;
	}
}

#define YUV2R(y, u, v) ({ \
		int r = (y) + ((((v) - 128) * 1436) >> 10); r > 255 ? 255 : r < 0 ? 0 : r; })
#define YUV2G(y, u, v) ({ \
		int g = (y) - ((((u) - 128) * 352 + ((v) - 128) * 731) >> 10); g > 255 ? 255 : g < 0 ? 0 : g; })
#define YUV2B(y, u, v) ({ \
		int b = (y) + ((((u) - 128) * 1814) >> 10); b > 255 ? 255 : b < 0 ? 0 : b; })

#define CLIP(color) (unsigned char)(((color) > 0xFF) ? 0xff : (((color) < 0) ? 0 : (color)))

void v4lconvert_yuv420_to_bgr24(const unsigned char *src, unsigned char *dest,
		int width, int height, int yvu)
{
	int i, j;

	const unsigned char *ysrc = src;
	const unsigned char *usrc, *vsrc;

	if (yvu) {
		vsrc = src + width * height;
		usrc = vsrc + (width * height) / 4;
	} else {
		usrc = src + width * height;
		vsrc = usrc + (width * height) / 4;
	}

	for (i = 0; i < height; i++) {
		for (j = 0; j < width; j += 2) {
#if 1 /* fast slightly less accurate multiplication free code */
			int u1 = (((*usrc - 128) << 7) +  (*usrc - 128)) >> 6;
			int rg = (((*usrc - 128) << 1) +  (*usrc - 128) +
					((*vsrc - 128) << 2) + ((*vsrc - 128) << 1)) >> 3;
			int v1 = (((*vsrc - 128) << 1) +  (*vsrc - 128)) >> 1;

			*dest++ = CLIP(*ysrc + u1);
			*dest++ = CLIP(*ysrc - rg);
			*dest++ = CLIP(*ysrc + v1);
			ysrc++;

			*dest++ = CLIP(*ysrc + u1);
			*dest++ = CLIP(*ysrc - rg);
			*dest++ = CLIP(*ysrc + v1);
#else
			*dest++ = YUV2B(*ysrc, *usrc, *vsrc);
			*dest++ = YUV2G(*ysrc, *usrc, *vsrc);
			*dest++ = YUV2R(*ysrc, *usrc, *vsrc);
			ysrc++;

			*dest++ = YUV2B(*ysrc, *usrc, *vsrc);
			*dest++ = YUV2G(*ysrc, *usrc, *vsrc);
			*dest++ = YUV2R(*ysrc, *usrc, *vsrc);
#endif
			ysrc++;
			usrc++;
			vsrc++;
		}
		/* Rewind u and v for next line */
		if (!(i & 1)) {
			usrc -= width / 2;
			vsrc -= width / 2;
		}
	}
}

void v4lconvert_yuv420_to_rgb24(const unsigned char *src, unsigned char *dest,
		int width, int height, int yvu)
{
	int i, j;

	const unsigned char *ysrc = src;
	const unsigned char *usrc, *vsrc;

	if (yvu) {
		vsrc = src + width * height;
		usrc = vsrc + (width * height) / 4;
	} else {
		usrc = src + width * height;
		vsrc = usrc + (width * height) / 4;
	}

	for (i = 0; i < height; i++) {
		for (j = 0; j < width; j += 2) {
#if 1 /* fast slightly less accurate multiplication free code */
			int u1 = (((*usrc - 128) << 7) +  (*usrc - 128)) >> 6;
			int rg = (((*usrc - 128) << 1) +  (*usrc - 128) +
					((*vsrc - 128) << 2) + ((*vsrc - 128) << 1)) >> 3;
			int v1 = (((*vsrc - 128) << 1) +  (*vsrc - 128)) >> 1;

			*dest++ = CLIP(*ysrc + v1);
			*dest++ = CLIP(*ysrc - rg);
			*dest++ = CLIP(*ysrc + u1);
			ysrc++;

			*dest++ = CLIP(*ysrc + v1);
			*dest++ = CLIP(*ysrc - rg);
			*dest++ = CLIP(*ysrc + u1);
#else
			*dest++ = YUV2R(*ysrc, *usrc, *vsrc);
			*dest++ = YUV2G(*ysrc, *usrc, *vsrc);
			*dest++ = YUV2B(*ysrc, *usrc, *vsrc);
			ysrc++;

			*dest++ = YUV2R(*ysrc, *usrc, *vsrc);
			*dest++ = YUV2G(*ysrc, *usrc, *vsrc);
			*dest++ = YUV2B(*ysrc, *usrc, *vsrc);
#endif
			ysrc++;
			usrc++;
			vsrc++;
		}
		/* Rewind u and v for next line */
		if (!(i&1)) {
			usrc -= width / 2;
			vsrc -= width / 2;
		}
	}
}

void v4lconvert_yuyv_to_bgr24(const unsigned char *src, unsigned char *dest,
		int width, int height)
{
	int j;

	while (--height >= 0) {
		for (j = 0; j < width; j += 2) {
			int u = src[1];
			int v = src[3];
			int u1 = (((u - 128) << 7) +  (u - 128)) >> 6;
			int rg = (((u - 128) << 1) +  (u - 128) +
					((v - 128) << 2) + ((v - 128) << 1)) >> 3;
			int v1 = (((v - 128) << 1) +  (v - 128)) >> 1;

			*dest++ = CLIP(src[0] + u1);
			*dest++ = CLIP(src[0] - rg);
			*dest++ = CLIP(src[0] + v1);

			*dest++ = CLIP(src[2] + u1);
			*dest++ = CLIP(src[2] - rg);
			*dest++ = CLIP(src[2] + v1);
			src += 4;
		}
	}
}

void v4lconvert_yuyv_to_rgb24(const unsigned char *src, unsigned char *dest,
		int width, int height)
{
	int j;

	while (--height >= 0) {
		for (j = 0; j < width; j += 2) {
			int u = src[1];
			int v = src[3];
			int u1 = (((u - 128) << 7) +  (u - 128)) >> 6;
			int rg = (((u - 128) << 1) +  (u - 128) +
					((v - 128) << 2) + ((v - 128) << 1)) >> 3;
			int v1 = (((v - 128) << 1) +  (v - 128)) >> 1;

			*dest++ = CLIP(src[0] + v1);
			*dest++ = CLIP(src[0] - rg);
			*dest++ = CLIP(src[0] + u1);

			*dest++ = CLIP(src[2] + v1);
			*dest++ = CLIP(src[2] - rg);
			*dest++ = CLIP(src[2] + u1);
			src += 4;
		}
	}
}

void v4lconvert_yuyv_to_yuv420(const unsigned char *src, unsigned char *dest,
		int width, int height, int yvu)
{
	int i, j;
	const unsigned char *src1;
	unsigned char *udest, *vdest;

	/* copy the Y values */
	src1 = src;
	for (i = 0; i < height; i++) {
		for (j = 0; j < width; j += 2) {
			*dest++ = src1[0];
			*dest++ = src1[2];
			src1 += 4;
		}
	}

	/* copy the U and V values */
	src++;				/* point to V */
	src1 = src + width * 2;		/* next line */
	if (yvu) {
		vdest = dest;
		udest = dest + width * height / 4;
	} else {
		udest = dest;
		vdest = dest + width * height / 4;
	}
	for (i = 0; i < height; i += 2) {
		for (j = 0; j < width; j += 2) {
			*udest++ = ((int) src[0] + src1[0]) / 2;	/* U */
			*vdest++ = ((int) src[2] + src1[2]) / 2;	/* V */
			src += 4;
			src1 += 4;
		}
		src = src1;
		src1 += width * 2;
	}
}

void v4lconvert_yvyu_to_bgr24(const unsigned char *src, unsigned char *dest,
		int width, int height)
{
	int j;

	while (--height >= 0) {
		for (j = 0; j < width; j += 2) {
			int u = src[3];
			int v = src[1];
			int u1 = (((u - 128) << 7) +  (u - 128)) >> 6;
			int rg = (((u - 128) << 1) +  (u - 128) +
					((v - 128) << 2) + ((v - 128) << 1)) >> 3;
			int v1 = (((v - 128) << 1) +  (v - 128)) >> 1;

			*dest++ = CLIP(src[0] + u1);
			*dest++ = CLIP(src[0] - rg);
			*dest++ = CLIP(src[0] + v1);

			*dest++ = CLIP(src[2] + u1);
			*dest++ = CLIP(src[2] - rg);
			*dest++ = CLIP(src[2] + v1);
			src += 4;
		}
	}
}

void v4lconvert_yvyu_to_rgb24(const unsigned char *src, unsigned char *dest,
		int width, int height)
{
	int j;

	while (--height >= 0) {
		for (j = 0; j < width; j += 2) {
			int u = src[3];
			int v = src[1];
			int u1 = (((u - 128) << 7) +  (u - 128)) >> 6;
			int rg = (((u - 128) << 1) +  (u - 128) +
					((v - 128) << 2) + ((v - 128) << 1)) >> 3;
			int v1 = (((v - 128) << 1) +  (v - 128)) >> 1;

			*dest++ = CLIP(src[0] + v1);
			*dest++ = CLIP(src[0] - rg);
			*dest++ = CLIP(src[0] + u1);

			*dest++ = CLIP(src[2] + v1);
			*dest++ = CLIP(src[2] - rg);
			*dest++ = CLIP(src[2] + u1);
			src += 4;
		}
	}
}

void v4lconvert_uyvy_to_bgr24(const unsigned char *src, unsigned char *dest,
		int width, int height)
{
	int j;

	while (--height >= 0) {
		for (j = 0; j < width; j += 2) {
			int u = src[0];
			int v = src[2];
			int u1 = (((u - 128) << 7) +  (u - 128)) >> 6;
			int rg = (((u - 128) << 1) +  (u - 128) +
					((v - 128) << 2) + ((v - 128) << 1)) >> 3;
			int v1 = (((v - 128) << 1) +  (v - 128)) >> 1;

			*dest++ = CLIP(src[1] + u1);
			*dest++ = CLIP(src[1] - rg);
			*dest++ = CLIP(src[1] + v1);

			*dest++ = CLIP(src[3] + u1);
			*dest++ = CLIP(src[3] - rg);
			*dest++ = CLIP(src[3] + v1);
			src += 4;
		}
	}
}

void v4lconvert_uyvy_to_rgb24(const unsigned char *src, unsigned char *dest,
		int width, int height)
{
	int j;

	while (--height >= 0) {
		for (j = 0; j < width; j += 2) {
			int u = src[0];
			int v = src[2];
			int u1 = (((u - 128) << 7) +  (u - 128)) >> 6;
			int rg = (((u - 128) << 1) +  (u - 128) +
					((v - 128) << 2) + ((v - 128) << 1)) >> 3;
			int v1 = (((v - 128) << 1) +  (v - 128)) >> 1;

			*dest++ = CLIP(src[1] + v1);
			*dest++ = CLIP(src[1] - rg);
			*dest++ = CLIP(src[1] + u1);

			*dest++ = CLIP(src[3] + v1);
			*dest++ = CLIP(src[3] - rg);
			*dest++ = CLIP(src[3] + u1);
			src += 4;
		}
	}
}

void v4lconvert_uyvy_to_yuv420(const unsigned char *src, unsigned char *dest,
		int width, int height, int yvu)
{
	int i, j;
	const unsigned char *src1;
	unsigned char *udest, *vdest;

	/* copy the Y values */
	src1 = src;
	for (i = 0; i < height; i++) {
		for (j = 0; j < width; j += 2) {
			*dest++ = src1[1];
			*dest++ = src1[3];
			src1 += 4;
		}
	}

	/* copy the U and V values */
	src1 = src + width * 2;		/* next line */
	if (yvu) {
		vdest = dest;
		udest = dest + width * height / 4;
	} else {
		udest = dest;
		vdest = dest + width * height / 4;
	}
	for (i = 0; i < height; i += 2) {
		for (j = 0; j < width; j += 2) {
			*udest++ = ((int) src[0] + src1[0]) / 2;	/* U */
			*vdest++ = ((int) src[2] + src1[2]) / 2;	/* V */
			src += 4;
			src1 += 4;
		}
		src = src1;
		src1 += width * 2;
	}
}

void v4lconvert_swap_rgb(const unsigned char *src, unsigned char *dst,
		int width, int height)
{
	int i;

	for (i = 0; i < (width * height); i++) {
		unsigned char tmp0, tmp1;
		tmp0 = *src++;
		tmp1 = *src++;
		*dst++ = *src++;
		*dst++ = tmp1;
		*dst++ = tmp0;
	}
}

void v4lconvert_swap_uv(const unsigned char *src, unsigned char *dest,
		const struct v4l2_format *src_fmt)
{
	int y;

	/* Copy Y */
	for (y = 0; y < src_fmt->fmt.pix.height; y++) {
		memcpy(dest, src, src_fmt->fmt.pix.width);
		dest += src_fmt->fmt.pix.width;
		src += src_fmt->fmt.pix.bytesperline;
	}

	/* Copy component 2 */
	src += src_fmt->fmt.pix.height * src_fmt->fmt.pix.bytesperline / 4;
	for (y = 0; y < src_fmt->fmt.pix.height / 2; y++) {
		memcpy(dest, src, src_fmt->fmt.pix.width / 2);
		dest += src_fmt->fmt.pix.width / 2;
		src += src_fmt->fmt.pix.bytesperline / 2;
	}

	/* Copy component 1 */
	src -= src_fmt->fmt.pix.height * src_fmt->fmt.pix.bytesperline / 2;
	for (y = 0; y < src_fmt->fmt.pix.height / 2; y++) {
		memcpy(dest, src, src_fmt->fmt.pix.width / 2);
		dest += src_fmt->fmt.pix.width / 2;
		src += src_fmt->fmt.pix.bytesperline / 2;
	}
}

void v4lconvert_rgb565_to_rgb24(const unsigned char *src, unsigned char *dest,
		int width, int height)
{
	int j;
	while (--height >= 0) {
		for (j = 0; j < width; j++) {
			unsigned short tmp = *(unsigned short *)src;

			/* Original format: rrrrrggg gggbbbbb */
			*dest++ = 0xf8 & (tmp >> 8);
			*dest++ = 0xfc & (tmp >> 3);
			*dest++ = 0xf8 & (tmp << 3);

			src += 2;
		}
	}
}

void v4lconvert_rgb565_to_bgr24(const unsigned char *src, unsigned char *dest,
		int width, int height)
{
	int j;
	while (--height >= 0) {
		for (j = 0; j < width; j++) {
			unsigned short tmp = *(unsigned short *)src;

			/* Original format: rrrrrggg gggbbbbb */
			*dest++ = 0xf8 & (tmp << 3);
			*dest++ = 0xfc & (tmp >> 3);
			*dest++ = 0xf8 & (tmp >> 8);

			src += 2;
		}
	}
}

void v4lconvert_rgb565_to_yuv420(const unsigned char *src, unsigned char *dest,
		const struct v4l2_format *src_fmt, int yvu)
{
	int x, y;
	unsigned short tmp;
	unsigned char *udest, *vdest;
	unsigned r[4], g[4], b[4];
	int avg_src[3];

	/* Y */
	for (y = 0; y < src_fmt->fmt.pix.height; y++) {
		for (x = 0; x < src_fmt->fmt.pix.width; x++) {
			tmp = *(unsigned short *)src;
			r[0] = 0xf8 & (tmp << 3);
			g[0] = 0xfc & (tmp >> 3);
			b[0] = 0xf8 & (tmp >> 8);
			RGB2Y(r[0], g[0], b[0], *dest++);
			src += 2;
		}
		src += src_fmt->fmt.pix.bytesperline - 2 * src_fmt->fmt.pix.width;
	}
	src -= src_fmt->fmt.pix.height * src_fmt->fmt.pix.bytesperline;

	/* U + V */
	if (yvu) {
		vdest = dest;
		udest = dest + src_fmt->fmt.pix.width * src_fmt->fmt.pix.height / 4;
	} else {
		udest = dest;
		vdest = dest + src_fmt->fmt.pix.width * src_fmt->fmt.pix.height / 4;
	}

	for (y = 0; y < src_fmt->fmt.pix.height / 2; y++) {
		for (x = 0; x < src_fmt->fmt.pix.width / 2; x++) {
			tmp = *(unsigned short *)src;
			r[0] = 0xf8 & (tmp << 3);
			g[0] = 0xfc & (tmp >> 3);
			b[0] = 0xf8 & (tmp >> 8);

			tmp = *(((unsigned short *)src) + 1);
			r[1] = 0xf8 & (tmp << 3);
			g[1] = 0xfc & (tmp >> 3);
			b[1] = 0xf8 & (tmp >> 8);

			tmp = *(((unsigned short *)src) + src_fmt->fmt.pix.bytesperline);
			r[2] = 0xf8 & (tmp << 3);
			g[2] = 0xfc & (tmp >> 3);
			b[2] = 0xf8 & (tmp >> 8);

			tmp = *(((unsigned short *)src) + src_fmt->fmt.pix.bytesperline + 1);
			r[3] = 0xf8 & (tmp << 3);
			g[3] = 0xfc & (tmp >> 3);
			b[3] = 0xf8 & (tmp >> 8);

			avg_src[0] = (r[0] + r[1] + r[2] + r[3]) / 4;
			avg_src[1] = (g[0] + g[1] + g[2] + g[3]) / 4;
			avg_src[2] = (b[0] + b[1] + b[2] + b[3]) / 4;
			RGB2UV(avg_src[0], avg_src[1], avg_src[2], *udest++, *vdest++);
			src += 4;
		}
		src += 2 * src_fmt->fmt.pix.bytesperline - 2 * src_fmt->fmt.pix.width;
	}
}
