nuclear@2: /*
nuclear@2: libimago - a multi-format image file input/output library.
nuclear@2: Copyright (C) 2010 John Tsiombikas <nuclear@member.fsf.org>
nuclear@2: 
nuclear@2: This program is free software: you can redistribute it and/or modify
nuclear@2: it under the terms of the GNU Lesser General Public License as published
nuclear@2: by the Free Software Foundation, either version 3 of the License, or
nuclear@2: (at your option) any later version.
nuclear@2: 
nuclear@2: This program is distributed in the hope that it will be useful,
nuclear@2: but WITHOUT ANY WARRANTY; without even the implied warranty of
nuclear@2: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
nuclear@2: GNU Lesser General Public License for more details.
nuclear@2: 
nuclear@2: You should have received a copy of the GNU Lesser General Public License
nuclear@2: along with this program.  If not, see <http://www.gnu.org/licenses/>.
nuclear@2: */
nuclear@2: #include <string.h>
nuclear@2: #include "imago2.h"
nuclear@2: 
nuclear@2: /* pixel-format conversions are sub-optimal at the moment to avoid
nuclear@2:  * writing a lot of code. optimize at some point ?
nuclear@2:  */
nuclear@2: 
nuclear@2: #define CLAMP(x, a, b)	((x) < (a) ? (a) : ((x) > (b) ? (b) : (x)))
nuclear@2: 
nuclear@2: struct pixel {
nuclear@2: 	float r, g, b, a;
nuclear@2: };
nuclear@2: 
nuclear@2: static void unpack_grey8(struct pixel *unp, void *pptr, int count);
nuclear@2: static void unpack_rgb24(struct pixel *unp, void *pptr, int count);
nuclear@2: static void unpack_rgba32(struct pixel *unp, void *pptr, int count);
nuclear@2: static void unpack_greyf(struct pixel *unp, void *pptr, int count);
nuclear@2: static void unpack_rgbf(struct pixel *unp, void *pptr, int count);
nuclear@2: static void unpack_rgbaf(struct pixel *unp, void *pptr, int count);
nuclear@2: 
nuclear@2: static void pack_grey8(void *pptr, struct pixel *unp, int count);
nuclear@2: static void pack_rgb24(void *pptr, struct pixel *unp, int count);
nuclear@2: static void pack_rgba32(void *pptr, struct pixel *unp, int count);
nuclear@2: static void pack_greyf(void *pptr, struct pixel *unp, int count);
nuclear@2: static void pack_rgbf(void *pptr, struct pixel *unp, int count);
nuclear@2: static void pack_rgbaf(void *pptr, struct pixel *unp, int count);
nuclear@2: 
nuclear@2: /* XXX keep in sync with enum img_fmt at imago2.h */
nuclear@2: static void (*unpack[])(struct pixel*, void*, int) = {
nuclear@2: 	unpack_grey8,
nuclear@2: 	unpack_rgb24,
nuclear@2: 	unpack_rgba32,
nuclear@2: 	unpack_greyf,
nuclear@2: 	unpack_rgbf,
nuclear@2: 	unpack_rgbaf
nuclear@2: };
nuclear@2: 
nuclear@2: /* XXX keep in sync with enum img_fmt at imago2.h */
nuclear@2: static void (*pack[])(void*, struct pixel*, int) = {
nuclear@2: 	pack_grey8,
nuclear@2: 	pack_rgb24,
nuclear@2: 	pack_rgba32,
nuclear@2: 	pack_greyf,
nuclear@2: 	pack_rgbf,
nuclear@2: 	pack_rgbaf
nuclear@2: };
nuclear@2: 
nuclear@2: 
nuclear@2: int img_convert(struct img_pixmap *img, enum img_fmt tofmt)
nuclear@2: {
nuclear@2: 	struct pixel pbuf[8];
nuclear@2: 	int bufsz = (img->width & 7) == 0 ? 8 : ((img->width & 3) == 0 ? 4 : 1);
nuclear@2: 	int i, num_pix = img->width * img->height;
nuclear@2: 	int num_iter = num_pix / bufsz;
nuclear@2: 	char *sptr, *dptr;
nuclear@2: 	struct img_pixmap nimg;
nuclear@2: 
nuclear@2: 	if(img->fmt == tofmt) {
nuclear@2: 		return 0;	/* nothing to do */
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	img_init(&nimg);
nuclear@2: 	if(img_set_pixels(&nimg, img->width, img->height, tofmt, 0) == -1) {
nuclear@2: 		img_destroy(&nimg);
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	sptr = img->pixels;
nuclear@2: 	dptr = nimg.pixels;
nuclear@2: 
nuclear@2: 	for(i=0; i<num_iter; i++) {
nuclear@2: 		unpack[img->fmt](pbuf, sptr, bufsz);
nuclear@2: 		pack[tofmt](dptr, pbuf, bufsz);
nuclear@2: 
nuclear@2: 		sptr += bufsz * img->pixelsz;
nuclear@2: 		dptr += bufsz * nimg.pixelsz;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	img_copy(img, &nimg);
nuclear@2: 	img_destroy(&nimg);
nuclear@2: 	return 0;
nuclear@2: }
nuclear@2: 
nuclear@2: /* the following functions *could* benefit from SIMD */
nuclear@2: 
nuclear@2: static void unpack_grey8(struct pixel *unp, void *pptr, int count)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 	unsigned char *pix = pptr;
nuclear@2: 
nuclear@2: 	for(i=0; i<count; i++) {
nuclear@2: 		unp->r = unp->g = unp->b = (float)*pix++ / 255.0;
nuclear@2: 		unp->a = 1.0;
nuclear@2: 		unp++;
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: static void unpack_rgb24(struct pixel *unp, void *pptr, int count)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 	unsigned char *pix = pptr;
nuclear@2: 
nuclear@2: 	for(i=0; i<count; i++) {
nuclear@2: 		unp->r = (float)*pix++ / 255.0;
nuclear@2: 		unp->g = (float)*pix++ / 255.0;
nuclear@2: 		unp->b = (float)*pix++ / 255.0;
nuclear@2: 		unp->a = 1.0;
nuclear@2: 		unp++;
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: static void unpack_rgba32(struct pixel *unp, void *pptr, int count)
nuclear@2: {
nuclear@2: 	memcpy(unp, pptr, count * sizeof *unp);
nuclear@2: }
nuclear@2: 
nuclear@2: static void unpack_greyf(struct pixel *unp, void *pptr, int count)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 	float *pix = pptr;
nuclear@2: 
nuclear@2: 	for(i=0; i<count; i++) {
nuclear@2: 		unp->r = unp->g = unp->b = *pix++;
nuclear@2: 		unp->a = 1.0;
nuclear@2: 		unp++;
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: static void unpack_rgbf(struct pixel *unp, void *pptr, int count)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 	float *pix = pptr;
nuclear@2: 
nuclear@2: 	for(i=0; i<count; i++) {
nuclear@2: 		unp->r = *pix++;
nuclear@2: 		unp->g = *pix++;
nuclear@2: 		unp->b = *pix++;
nuclear@2: 		unp->a = 1.0;
nuclear@2: 		unp++;
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: static void unpack_rgbaf(struct pixel *unp, void *pptr, int count)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 	float *pix = pptr;
nuclear@2: 
nuclear@2: 	for(i=0; i<count; i++) {
nuclear@2: 		unp->r = *pix++;
nuclear@2: 		unp->g = *pix++;
nuclear@2: 		unp->b = *pix++;
nuclear@2: 		unp->a = *pix++;
nuclear@2: 		unp++;
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: static void pack_grey8(void *pptr, struct pixel *unp, int count)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 	unsigned char *pix = pptr;
nuclear@2: 
nuclear@2: 	for(i=0; i<count; i++) {
nuclear@2: 		int lum = (int)(255.0 * (unp->r + unp->g + unp->b) / 3.0);
nuclear@2: 		*pix++ = CLAMP(lum, 0, 255);
nuclear@2: 		unp++;
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: static void pack_rgb24(void *pptr, struct pixel *unp, int count)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 	unsigned char *pix = pptr;
nuclear@2: 
nuclear@2: 	for(i=0; i<count; i++) {
nuclear@2: 		int r = (int)(unp->r * 255.0);
nuclear@2: 		int g = (int)(unp->g * 255.0);
nuclear@2: 		int b = (int)(unp->b * 255.0);
nuclear@2: 
nuclear@2: 		*pix++ = CLAMP(r, 0, 255);
nuclear@2: 		*pix++ = CLAMP(g, 0, 255);
nuclear@2: 		*pix++ = CLAMP(b, 0, 255);
nuclear@2: 		unp++;
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: static void pack_rgba32(void *pptr, struct pixel *unp, int count)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 	unsigned char *pix = pptr;
nuclear@2: 
nuclear@2: 	for(i=0; i<count; i++) {
nuclear@2: 		int r = (int)(unp->r * 255.0);
nuclear@2: 		int g = (int)(unp->g * 255.0);
nuclear@2: 		int b = (int)(unp->b * 255.0);
nuclear@2: 		int a = (int)(unp->a * 255.0);
nuclear@2: 
nuclear@2: 		*pix++ = CLAMP(r, 0, 255);
nuclear@2: 		*pix++ = CLAMP(g, 0, 255);
nuclear@2: 		*pix++ = CLAMP(b, 0, 255);
nuclear@2: 		*pix++ = CLAMP(a, 0, 255);
nuclear@2: 		unp++;
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: static void pack_greyf(void *pptr, struct pixel *unp, int count)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 	float *pix = pptr;
nuclear@2: 
nuclear@2: 	for(i=0; i<count; i++) {
nuclear@2: 		*pix++ = (unp->r + unp->g + unp->b) / 3.0;
nuclear@2: 		unp++;
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: static void pack_rgbf(void *pptr, struct pixel *unp, int count)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 	float *pix = pptr;
nuclear@2: 
nuclear@2: 	for(i=0; i<count; i++) {
nuclear@2: 		*pix++ = unp->r;
nuclear@2: 		*pix++ = unp->g;
nuclear@2: 		*pix++ = unp->b;
nuclear@2: 		unp++;
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: static void pack_rgbaf(void *pptr, struct pixel *unp, int count)
nuclear@2: {
nuclear@2: 	memcpy(pptr, unp, count * sizeof *unp);
nuclear@2: }
nuclear@2: