X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=demo_prior;a=blobdiff_plain;f=libs%2Fimago2%2Fsrc%2Ffile_ppm.c;fp=libs%2Fimago2%2Fsrc%2Ffile_ppm.c;h=55aa5e3d9ea0ab011f7f9f9fdd0a3e34b8e24945;hp=0000000000000000000000000000000000000000;hb=3a9f6854df479d81442273c9d0b133c49c5c8f66;hpb=0b24071f728b7c8550daa1b7aa7c4012cb70ef4c

diff --git a/libs/imago2/src/file_ppm.c b/libs/imago2/src/file_ppm.c
new file mode 100644
index 0000000..55aa5e3
--- /dev/null
+++ b/libs/imago2/src/file_ppm.c
@@ -0,0 +1,258 @@
+/*
+libimago - a multi-format image file input/output library.
+Copyright (C) 2010-2017 John Tsiombikas <nuclear@member.fsf.org>
+
+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 3 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, see <http://www.gnu.org/licenses/>.
+*/
+
+/* -- Portable Pixmap (PPM) module (also supports PGM) -- */
+
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include "imago2.h"
+#include "ftype_module.h"
+#include "byteord.h"
+
+static int check(struct img_io *io);
+static int read(struct img_pixmap *img, struct img_io *io);
+static int write(struct img_pixmap *img, struct img_io *io);
+
+int img_register_ppm(void)
+{
+	static struct ftype_module mod = {".ppm:.pgm:.pnm", check, read, write};
+	return img_register_module(&mod);
+}
+
+
+static int check(struct img_io *io)
+{
+	char id[2];
+	int res = -1;
+	long pos = io->seek(0, SEEK_CUR, io->uptr);
+
+	if(io->read(id, 2, io->uptr) < 2) {
+		io->seek(pos, SEEK_SET, io->uptr);
+		return -1;
+	}
+
+	if(id[0] == 'P' && (id[1] == '6' || id[1] == '3' || id[1] == '5')) {
+		res = 0;
+	}
+	io->seek(pos, SEEK_SET, io->uptr);
+	return res;
+}
+
+static int iofgetc(struct img_io *io)
+{
+	char c;
+	return io->read(&c, 1, io->uptr) < 1 ? -1 : c;
+}
+
+static char *iofgets(char *buf, int size, struct img_io *io)
+{
+	int c;
+	char *ptr = buf;
+
+	while(--size > 0 && (c = iofgetc(io)) != -1) {
+		*ptr++ = c;
+		if(c == '\n') break;
+	}
+	*ptr = 0;
+
+	return ptr == buf ? 0 : buf;
+}
+
+static int read(struct img_pixmap *img, struct img_io *io)
+{
+	char buf[256];
+	int xsz, ysz, maxval, got_hdrlines = 1;
+	int i, greyscale, numval, valsize, fbsize, text;
+	enum img_fmt fmt;
+
+	if(!iofgets(buf, sizeof buf, io)) {
+		return -1;
+	}
+	if(!(buf[0] == 'P' && (buf[1] == '6' || buf[1] == '3' || buf[1] == '5'))) {
+		return -1;
+	}
+	greyscale = buf[1] == '5' ? 1 : 0;
+	text = buf[1] == '3' ? 1 : 0;
+
+	while(got_hdrlines < 3 && iofgets(buf, sizeof buf, io)) {
+		if(buf[0] == '#') continue;
+
+		switch(got_hdrlines) {
+		case 1:
+			if(sscanf(buf, "%d %d\n", &xsz, &ysz) < 2) {
+				return -1;
+			}
+			break;
+
+		case 2:
+			if(sscanf(buf, "%d\n", &maxval) < 1) {
+				return -1;
+			}
+		default:
+			break;
+		}
+		got_hdrlines++;
+	}
+
+	if(xsz < 1 || ysz < 1 || maxval <= 0 || maxval > 65535) {
+		return -1;
+	}
+
+	valsize = maxval < 256 ? 1 : 2;
+	numval = xsz * ysz * (greyscale ? 1 : 3);
+	fbsize = numval * valsize;
+
+	if(valsize > 1) {
+		fmt = greyscale ? IMG_FMT_GREYF : IMG_FMT_RGBF;
+	} else {
+		fmt = greyscale ? IMG_FMT_GREY8 : IMG_FMT_RGB24;
+	}
+
+	if(img_set_pixels(img, xsz, ysz, fmt, 0) == -1) {
+		return -1;
+	}
+
+	if(!text) {
+		if(io->read(img->pixels, fbsize, io->uptr) < (unsigned int)fbsize) {
+			return -1;
+		}
+		if(maxval == 255) {
+			return 0;	/* we're done, no conversion necessary */
+		}
+
+		if(maxval < 256) {
+			unsigned char *ptr = img->pixels;
+			for(i=0; i<numval; i++) {
+				unsigned char c = *ptr * 255 / maxval;
+				*ptr++ = c;
+			}
+		} else {
+			/* we allocated a floating point framebuffer, and dropped the 16bit pixels
+			 * into it. To convert it in-place we'll iterate backwards from the end, since
+			 * otherwise each 32bit floating point value we store, would overwrite the next
+			 * pixel.
+			 */
+			uint16_t *src = (uint16_t*)img->pixels + numval;
+			float *dest = (float*)img->pixels + numval;
+
+			for(i=0; i<numval; i++) {
+				uint16_t val = *--src;
+#ifdef IMAGO_LITTLE_ENDIAN
+				val = (val >> 8) | (val << 8);
+#endif
+				*--dest = (float)val / (float)maxval;
+			}
+		}
+	} else {
+		char *pptr = img->pixels;
+		int c = iofgetc(io);
+
+		for(i=0; i<numval; i++) {
+			char *valptr = buf;
+
+			while(c != -1 && isspace(c)) {
+				c = iofgetc(io);
+			}
+
+			while(c != -1 && !isspace(c) && valptr - buf < sizeof buf - 1) {
+				*valptr++ = c;
+				c = iofgetc(io);
+			}
+			if(c == -1) break;
+			*valptr = 0;
+
+			*pptr++ = atoi(buf) * 255 / maxval;
+		}
+	}
+	return 0;
+}
+
+static int write(struct img_pixmap *img, struct img_io *io)
+{
+	int i, sz, nval, res = -1;
+	char buf[256];
+	float *fptr, maxfval;
+	struct img_pixmap tmpimg;
+	static const char *fmt = "P%d\n#written by libimago2\n%d %d\n%d\n";
+	int greyscale = img_is_greyscale(img);
+
+	nval = greyscale ? 1 : 3;
+
+	img_init(&tmpimg);
+
+	switch(img->fmt) {
+	case IMG_FMT_RGBA32:
+		if(img_copy(&tmpimg, img) == -1) {
+			goto done;
+		}
+		if(img_convert(&tmpimg, IMG_FMT_RGB24) == -1) {
+			goto done;
+		}
+		img = &tmpimg;
+
+	case IMG_FMT_RGB24:
+	case IMG_FMT_GREY8:
+		sprintf(buf, fmt, greyscale ? 5 : 6, img->width, img->height, 255);
+		if(io->write(buf, strlen(buf), io->uptr) < strlen(buf)) {
+			goto done;
+		}
+		sz = img->width * img->height * nval;
+		if(io->write(img->pixels, sz, io->uptr) < (unsigned int)sz) {
+			goto done;
+		}
+		res = 0;
+		break;
+
+	case IMG_FMT_RGBAF:
+		if(img_copy(&tmpimg, img) == -1) {
+			goto done;
+		}
+		if(img_convert(&tmpimg, IMG_FMT_RGBF) == -1) {
+			goto done;
+		}
+		img = &tmpimg;
+
+	case IMG_FMT_RGBF:
+	case IMG_FMT_GREYF:
+		sprintf(buf, fmt, greyscale ? 5 : 6, img->width, img->height, 65535);
+		if(io->write(buf, strlen(buf), io->uptr) < strlen(buf)) {
+			goto done;
+		}
+		fptr = img->pixels;
+		maxfval = 0;
+		for(i=0; i<img->width * img->height * nval; i++) {
+			float val = *fptr++;
+			if(val > maxfval) maxfval = val;
+		}
+		fptr = img->pixels;
+		for(i=0; i<img->width * img->height * nval; i++) {
+			uint16_t val = (uint16_t)(*fptr++ / maxfval * 65535.0);
+			img_write_uint16_be(io, val);
+		}
+		res = 0;
+		break;
+
+	default:
+		break;
+	}
+
+done:
+	img_destroy(&tmpimg);
+	return res;
+}