summaryrefslogtreecommitdiffstats
path: root/tools/shift_img.c
diff options
context:
space:
mode:
Diffstat (limited to 'tools/shift_img.c')
-rw-r--r--tools/shift_img.c165
1 files changed, 165 insertions, 0 deletions
diff --git a/tools/shift_img.c b/tools/shift_img.c
new file mode 100644
index 000000000..d421263f3
--- /dev/null
+++ b/tools/shift_img.c
@@ -0,0 +1,165 @@
+/*
+ * Guillaume Cottenceau (gc at mandrakesoft.com)
+ *
+ * Copyright 2002 MandrakeSoft
+ *
+ * This software may be freely redistributed under the terms of the GNU
+ * public license.
+ *
+ */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdarg.h>
+
+#define PNG_DEBUG 3
+#include <png.h>
+
+void abort_(const char * s, ...)
+{
+ va_list args;
+ va_start(args, s);
+ vfprintf(stderr, s, args);
+ fprintf(stderr, "\n");
+ va_end(args);
+ abort();
+}
+
+int x, y;
+
+int width, height;
+png_byte color_type;
+png_byte bit_depth;
+
+png_structp png_ptr;
+png_infop info_ptr;
+int number_of_passes;
+png_bytep * row_pointers;
+
+void read_png_file(char* file_name)
+{
+ char header[8]; // 8 is the maximum size that can be checked
+
+ /* open file and test for it being a png */
+ FILE *fp = fopen(file_name, "rb");
+ if (!fp)
+ abort_("[read_png_file] File %s could not be opened for reading", file_name);
+ fread(header, 1, 8, fp);
+ if (png_sig_cmp(header, 0, 8))
+ abort_("[read_png_file] File %s is not recognized as a PNG file", file_name);
+
+
+ /* initialize stuff */
+ png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+
+ if (!png_ptr)
+ abort_("[read_png_file] png_create_read_struct failed");
+
+ info_ptr = png_create_info_struct(png_ptr);
+ if (!info_ptr)
+ abort_("[read_png_file] png_create_info_struct failed");
+
+ if (setjmp(png_jmpbuf(png_ptr)))
+ abort_("[read_png_file] Error during init_io");
+
+ png_init_io(png_ptr, fp);
+ png_set_sig_bytes(png_ptr, 8);
+
+ png_read_info(png_ptr, info_ptr);
+
+ width = info_ptr->width;
+ height = info_ptr->height;
+ color_type = info_ptr->color_type;
+ bit_depth = info_ptr->bit_depth;
+
+ number_of_passes = png_set_interlace_handling(png_ptr);
+ png_read_update_info(png_ptr, info_ptr);
+
+
+ /* read file */
+ if (setjmp(png_jmpbuf(png_ptr)))
+ abort_("[read_png_file] Error during read_image");
+
+ row_pointers = (png_bytep*) malloc(sizeof(png_bytep) * height);
+ for (y=0; y<height; y++)
+ row_pointers[y] = (png_byte*) malloc(info_ptr->rowbytes);
+
+ png_read_image(png_ptr, row_pointers);
+}
+
+
+void write_png_file(char* file_name)
+{
+ /* create file */
+ FILE *fp = fopen(file_name, "wb");
+ if (!fp)
+ abort_("[write_png_file] File %s could not be opened for writing", file_name);
+
+
+ /* initialize stuff */
+ png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+
+ if (!png_ptr)
+ abort_("[write_png_file] png_create_write_struct failed");
+
+ info_ptr = png_create_info_struct(png_ptr);
+ if (!info_ptr)
+ abort_("[write_png_file] png_create_info_struct failed");
+
+ if (setjmp(png_jmpbuf(png_ptr)))
+ abort_("[write_png_file] Error during init_io");
+
+ png_init_io(png_ptr, fp);
+
+
+ /* write header */
+ if (setjmp(png_jmpbuf(png_ptr)))
+ abort_("[write_png_file] Error during writing header");
+
+ png_set_IHDR(png_ptr, info_ptr, width, height,
+ bit_depth, color_type, PNG_INTERLACE_NONE,
+ PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+ png_write_info(png_ptr, info_ptr);
+
+
+ /* write bytes */
+ if (setjmp(png_jmpbuf(png_ptr)))
+ abort_("[write_png_file] Error during writing bytes");
+
+ png_write_image(png_ptr, row_pointers);
+
+
+ /* end write */
+ if (setjmp(png_jmpbuf(png_ptr)))
+ abort_("[write_png_file] Error during end of write");
+
+ png_write_end(png_ptr, NULL);
+
+}
+
+void process_file(char* shift)
+{
+ int shift_ = atoi(shift);
+
+ if (info_ptr->color_type != PNG_COLOR_TYPE_RGBA)
+ abort_("[process_file] color_type of input file must be PNG_COLOR_TYPE_RGBA (is %d)", info_ptr->color_type);
+
+ width -= shift_;
+ for (y=0; y<height; y++) {
+ row_pointers[y] += 4 * shift_;
+ }
+
+}
+
+
+int main(int argc, char **argv)
+{
+ if (argc != 4)
+ abort_("Usage: program_name <file_in> <file_out> <shift>");
+
+ read_png_file(argv[1]);
+ process_file(argv[3]);
+ write_png_file(argv[2]);
+}