wrlib: Renamed image format related files for clarity

This patch makes all files appear together when listing files and
it is more clear about their function.

Signed-off-by: Christophe CURIS <christophe.curis@free.fr>

wrlib/load_png.c

@@ -0,0 +1,215 @@
+/* png.c - load PNG image from file
+ *
+ * Raster graphics library
+ *
+ * Copyright (c) 1997-2003 Alfredo K. Kojima
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Library General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *
+ *  This library 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
+ *  Library General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Library General Public
+ *  License along with this library; if not, write to the Free
+ *  Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+ *  MA 02110-1301, USA.
+ */
+
+#include <config.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <png.h>
+
+#include "wraster.h"
+#include "imgformat.h"
+
+RImage *RLoadPNG(RContext *context, const char *file)
+{
+	char *tmp;
+	RImage *image = NULL;
+	FILE *f;
+	png_structp png;
+	png_infop pinfo, einfo;
+	png_color_16p bkcolor;
+	int alpha;
+	int x, y, i;
+	double gamma, sgamma;
+	png_uint_32 width, height;
+	int depth, junk, color_type;
+	png_bytep *png_rows;
+	unsigned char *ptr;
+
+	f = fopen(file, "rb");
+	if (!f) {
+		RErrorCode = RERR_OPEN;
+		return NULL;
+	}
+	png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, (png_error_ptr) NULL, (png_error_ptr) NULL);
+	if (!png) {
+		RErrorCode = RERR_NOMEMORY;
+		fclose(f);
+		return NULL;
+	}
+
+	pinfo = png_create_info_struct(png);
+	if (!pinfo) {
+		RErrorCode = RERR_NOMEMORY;
+		fclose(f);
+		png_destroy_read_struct(&png, NULL, NULL);
+		return NULL;
+	}
+
+	einfo = png_create_info_struct(png);
+	if (!einfo) {
+		RErrorCode = RERR_NOMEMORY;
+		fclose(f);
+		png_destroy_read_struct(&png, &pinfo, NULL);
+		return NULL;
+	}
+
+	RErrorCode = RERR_INTERNAL;
+#if PNG_LIBPNG_VER - 0 < 10400
+	if (setjmp(png->jmpbuf)) {
+#else
+	if (setjmp(png_jmpbuf(png))) {
+#endif
+		fclose(f);
+		png_destroy_read_struct(&png, &pinfo, &einfo);
+		if (image)
+			RReleaseImage(image);
+		return NULL;
+	}
+
+	png_init_io(png, f);
+
+	png_read_info(png, pinfo);
+
+	png_get_IHDR(png, pinfo, &width, &height, &depth, &color_type, &junk, &junk, &junk);
+
+	/* sanity check */
+	if (width < 1 || height < 1) {
+		fclose(f);
+		png_destroy_read_struct(&png, &pinfo, &einfo);
+		RErrorCode = RERR_BADIMAGEFILE;
+		return NULL;
+	}
+
+	/* check for an alpha channel */
+	if (png_get_valid(png, pinfo, PNG_INFO_tRNS))
+		alpha = True;
+	else
+		alpha = (color_type & PNG_COLOR_MASK_ALPHA);
+
+	/* allocate RImage */
+	image = RCreateImage(width, height, alpha);
+	if (!image) {
+		fclose(f);
+		png_destroy_read_struct(&png, &pinfo, &einfo);
+		return NULL;
+	}
+
+	/* normalize to 8bpp with alpha channel */
+	if (color_type == PNG_COLOR_TYPE_PALETTE && depth <= 8)
+		png_set_expand(png);
+
+	if (color_type == PNG_COLOR_TYPE_GRAY && depth <= 8)
+		png_set_expand(png);
+
+	if (png_get_valid(png, pinfo, PNG_INFO_tRNS))
+		png_set_expand(png);
+
+	if (depth == 16)
+		png_set_strip_16(png);
+
+	if (color_type == PNG_COLOR_TYPE_GRAY || color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+		png_set_gray_to_rgb(png);
+
+	/* set gamma correction */
+	if ((context->attribs->flags & RC_GammaCorrection)
+	    && context->depth != 8) {
+		sgamma = (context->attribs->rgamma + context->attribs->ggamma + context->attribs->bgamma) / 3;
+	} else if ((tmp = getenv("DISPLAY_GAMMA")) != NULL) {
+		sgamma = atof(tmp);
+		if (sgamma < 1.0E-3)
+			sgamma = 1;
+	} else {
+		/* blah */
+		sgamma = 2.2;
+	}
+
+	if (png_get_gAMA(png, pinfo, &gamma))
+		png_set_gamma(png, sgamma, gamma);
+	else
+		png_set_gamma(png, sgamma, 0.45);
+
+	/* do the transforms */
+	png_read_update_info(png, pinfo);
+
+	/* set background color */
+	if (png_get_bKGD(png, pinfo, &bkcolor)) {
+		image->background.red = bkcolor->red >> 8;
+		image->background.green = bkcolor->green >> 8;
+		image->background.blue = bkcolor->blue >> 8;
+	}
+
+	png_rows = calloc(height, sizeof(char *));
+	if (!png_rows) {
+		RErrorCode = RERR_NOMEMORY;
+		fclose(f);
+		RReleaseImage(image);
+		png_destroy_read_struct(&png, &pinfo, &einfo);
+		return NULL;
+	}
+	for (y = 0; y < height; y++) {
+		png_rows[y] = malloc(png_get_rowbytes(png, pinfo));
+		if (!png_rows[y]) {
+			RErrorCode = RERR_NOMEMORY;
+			fclose(f);
+			RReleaseImage(image);
+			png_destroy_read_struct(&png, &pinfo, &einfo);
+			while (y-- > 0)
+				if (png_rows[y])
+					free(png_rows[y]);
+			free(png_rows);
+			return NULL;
+		}
+	}
+	/* read data */
+	png_read_image(png, png_rows);
+
+	png_read_end(png, einfo);
+
+	png_destroy_read_struct(&png, &pinfo, &einfo);
+
+	fclose(f);
+
+	ptr = image->data;
+
+	/* convert to RImage */
+	if (alpha) {
+		for (y = 0; y < height; y++) {
+			for (x = 0, i = width * 4; x < i; x++, ptr++) {
+				*ptr = *(png_rows[y] + x);
+			}
+		}
+	} else {
+		for (y = 0; y < height; y++) {
+			for (x = 0, i = width * 3; x < i; x++, ptr++) {
+				*ptr = *(png_rows[y] + x);
+			}
+		}
+	}
+	for (y = 0; y < height; y++)
+		if (png_rows[y])
+			free(png_rows[y]);
+	free(png_rows);
+	return image;
+}