commit e5acf698b57f677016b201561d5e0810c5dfc82e
parent 6ef7062afe04cf91da61af69cca895c7d65883e0
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date: Tue, 29 Jul 2014 18:46:10 +0000
add gif2if
Diffstat:
| M | Makefile | | | 10 | +++++++--- |
| M | config.mk | | | 1 | + |
| A | gif2if.c | | | 184 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
3 files changed, 192 insertions(+), 3 deletions(-)
diff --git a/Makefile b/Makefile
@@ -3,10 +3,10 @@
include config.mk
-SRC = png2if.c if2png.c jpg2if.c
+SRC = png2if.c if2png.c jpg2if.c gif2if.c
OBJ = ${SRC:.c=.o}
-all: options png2if if2png jpg2if
+all: options png2if if2png jpg2if gif2if
options:
@echo imagefile build options:
@@ -20,6 +20,10 @@ options:
${OBJ}: config.mk
+gif2if: gif2if.o
+ @echo CC -o $@
+ @${CC} -o $@ gif2if.o ${LDFLAGS} ${GIF_LIBS}
+
jpg2if: jpg2if.o
@echo CC -o $@
@${CC} -o $@ jpg2if.o ${LDFLAGS} ${JPEG_LIBS}
@@ -34,7 +38,7 @@ if2png: if2png.o
clean:
@echo cleaning
- @rm -f png2if if2png jpg2if ${OBJ}
+ @rm -f png2if if2png jpg2if gif2if ${OBJ}
install: all
@echo installing executable files to ${DESTDIR}${PREFIX}/bin
diff --git a/config.mk b/config.mk
@@ -7,6 +7,7 @@ PREFIX = /usr/local
LIBS =
PNG_LIBS = -lpng
JPEG_LIBS = -ljpeg
+GIF_LIBS = -lgif
# flags
CFLAGS = -std=c90 -ansi -pedantic -Wall -Wextra -Os
diff --git a/gif2if.c b/gif2if.c
@@ -0,0 +1,184 @@
+/* See LICENSE file for copyright and license details.
+ * code borrowed from util/gif2rgb.c from giflib-5.0 */
+#include <arpa/inet.h>
+#include <errno.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <gif_lib.h>
+#include "arg.h"
+
+char *argv0;
+
+static void
+usage(void)
+{
+ fprintf(stderr, "usage: %s\n", argv0);
+ exit(EXIT_FAILURE);
+}
+
+static void
+die(const char *s) {
+ fputs(s, stderr);
+ exit(EXIT_FAILURE);
+}
+
+void
+gif_print_error(int code)
+{
+ const char *err = GifErrorString(code);
+
+ if(err != NULL)
+ fprintf(stderr, "GIF-LIB error: %s.\n", err);
+ else
+ fprintf(stderr, "GIF-LIB undefined error %d.\n", code);
+ exit(EXIT_FAILURE);
+}
+
+void *
+emalloc(size_t size) {
+ void *p;
+
+ if(!(p = malloc(size)))
+ die("can't malloc\n");
+ return p;
+}
+
+int
+main(int argc, char *argv[])
+{
+ GifRecordType recordtype;
+ GifFileType *giffile;
+ GifRowType * gifrows;
+ GifByteType *extension;
+ GifColorType *colormapentry;
+ ColorMapObject *colormap;
+ uint32_t width, height, rwidth, rheight, val_be;
+ uint32_t i, j, k;
+ size_t gif_row_len;
+ uint8_t *if_row;
+ int errorcode, extcode, row, col, imagenum = 0;
+ int interlacedoffset[] = { 0, 4, 2, 1 };
+ int interlacedjumps[] = { 8, 8, 4, 2 };
+
+ ARGBEGIN {
+ default:
+ usage();
+ } ARGEND;
+
+ if (argc != 0)
+ usage();
+
+ /* load gif */
+ if ((giffile = DGifOpenFileHandle(0, &errorcode)) == NULL)
+ gif_print_error(errorcode);
+
+ width = (uint32_t)giffile->SWidth;
+ height = (uint32_t)giffile->SHeight;
+ gif_row_len = giffile->SWidth * sizeof(GifPixelType);
+ gifrows = emalloc(giffile->SHeight * sizeof(GifRowType));
+ gifrows[0] = emalloc(gif_row_len);
+
+ /* set color to BackGround. */
+ for (i = 0; i < width; i++)
+ gifrows[0][i] = giffile->SBackGroundColor;
+ for(i = 1; i < height; i++) {
+ gifrows[i] = emalloc(gif_row_len);
+ memcpy(gifrows[i], gifrows[0], gif_row_len);
+ }
+
+ /* scan the content of the GIF file and load the image(s) in: */
+ do {
+ if (DGifGetRecordType(giffile, &recordtype) == GIF_ERROR)
+ gif_print_error(giffile->Error);
+
+ switch (recordtype) {
+ case IMAGE_DESC_RECORD_TYPE:
+ if (DGifGetImageDesc(giffile) == GIF_ERROR)
+ gif_print_error(giffile->Error);
+
+ /* image position relative to Screen. */
+ row = giffile->Image.Top;
+ col = giffile->Image.Left;
+ rwidth = giffile->Image.Width;
+ rheight = giffile->Image.Height;
+ if (giffile->Image.Left + giffile->Image.Width > giffile->SWidth ||
+ giffile->Image.Top + giffile->Image.Height > giffile->SHeight) {
+ fprintf(stderr, "Image %d is not confined to screen dimension, aborted.\n", imagenum);
+ exit(EXIT_FAILURE);
+ }
+ if (giffile->Image.Interlace) {
+ /* need to perform 4 passes on the images: */
+ for (i = 0; i < 4; i++) {
+ for (j = row + interlacedoffset[i]; j < row + rheight; j += interlacedjumps[i]) {
+ if (DGifGetLine(giffile, &gifrows[j][col], rwidth) == GIF_ERROR)
+ gif_print_error(giffile->Error);
+ }
+ }
+ } else {
+ for (i = 0; i < rheight; i++) {
+ if (DGifGetLine(giffile, &gifrows[row++][col], rwidth) == GIF_ERROR)
+ gif_print_error(giffile->Error);
+ }
+ }
+ /* this is set to disallow multiple images */
+ recordtype = TERMINATE_RECORD_TYPE;
+ imagenum++;
+ break;
+ case EXTENSION_RECORD_TYPE:
+ /* Skip any extension blocks in file: */
+ if (DGifGetExtension(giffile, &extcode, &extension) == GIF_ERROR)
+ gif_print_error(giffile->Error);
+ while (extension != NULL) {
+ if (DGifGetExtensionNext(giffile, &extension) == GIF_ERROR)
+ gif_print_error(giffile->Error);
+ }
+ break;
+ case TERMINATE_RECORD_TYPE:
+ break;
+ default:
+ break;
+ }
+ } while (recordtype != TERMINATE_RECORD_TYPE);
+
+ if(giffile->Image.ColorMap)
+ colormap = giffile->Image.ColorMap;
+ else
+ colormap = giffile->SColorMap;
+
+ if(colormap == NULL)
+ die("Gif Image does not have a colormap\n");
+
+ /* write header with big endian width and height-values */
+ fprintf(stdout, "imagefile");
+ val_be = htonl(width);
+ fwrite(&val_be, sizeof(uint32_t), 1, stdout);
+ val_be = htonl(height);
+ fwrite(&val_be, sizeof(uint32_t), 1, stdout);
+
+ gif_row_len = width * strlen("RGBA");
+ if_row = emalloc(gif_row_len);
+
+ /* write data */
+ for (i = 0; i < height; i++) {
+ for(j = 0, k = 0; j < width; j++, k += 4) {
+ colormapentry = &colormap->Colors[gifrows[i][j]];
+ if_row[k] = colormapentry->Red;
+ if_row[k+1] = colormapentry->Green;
+ if_row[k+2] = colormapentry->Blue;
+ if_row[k+3] = 255; /* TODO: mask? */
+ }
+ if (fwrite(if_row, 1, gif_row_len, stdout) != gif_row_len)
+ die("fwrite() failed\n");
+ }
+
+ /* cleanup */
+ for(i = 0; i < height; i++)
+ free(gifrows[i]);
+ free(gifrows);
+ free(if_row);
+
+ return EXIT_SUCCESS;
+}
