78 lines
1.9 KiB
C
78 lines
1.9 KiB
C
// TODO: handle big/little endian ?
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#include <stdio.h>
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#include <stdlib.h>
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#include <stdint.h>
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#include <unistd.h>
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#include <fcntl.h>
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#define STB_IMAGE_IMPLEMENTATION
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#include "stb_image.h"
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uint16_t engine_color_32_to_16(uint8_t r, uint8_t g, uint8_t b, uint8_t a) {
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uint16_t color16;
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r = r >> 4;
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g = g >> 4;
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b = b >> 4;
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a = a >> 4;
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color16 = (a << 12) | (r << 8) | (g << 4) | b;
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return color16;
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}
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int main(int argc, char **argv) {
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if (argc != 3) {
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fprintf(stderr,"Not the right number of arguments, syntax: tex <file> <outfile>\n");
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return 1;
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}
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int width;
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int height;
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int components;
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unsigned char * data = stbi_load(argv[1],&width,&height,&components,4);
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if (data == NULL) {
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fprintf(stderr,"stb_image could not decode input file.\n");
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return 1;
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}
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int file = open(argv[2],O_WRONLY | O_CREAT | O_TRUNC,0644);
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if (file == -1) {
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fprintf(stderr,"Could not open output file (No permissions? Does not exist?).\n");
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return 1;
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}
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uint16_t width2 = (uint16_t)width;
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uint16_t height2 = (uint16_t)height;
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if (write(file,&width2,sizeof(uint16_t)) != sizeof(uint16_t)) {
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fprintf(stderr,"Could not write image to output file.\n");
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}
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if (write(file,&height2,sizeof(uint16_t)) != sizeof(uint16_t)) {
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fprintf(stderr,"Could not write image to output file.\n");
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}
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uint16_t * outbuffer = malloc(sizeof(uint16_t) * width * height);
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if (outbuffer == NULL) {
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fprintf(stderr,"Could not allocate output buffer in memory.\n");
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return 1;
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}
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uint32_t pixelIndex = 0;
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while (pixelIndex < width * height * 4) {
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uint16_t color = engine_color_32_to_16(
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data[pixelIndex],
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data[pixelIndex + 1],
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data[pixelIndex + 2],
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data[pixelIndex + 3]
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);
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outbuffer[pixelIndex / 4] = color;
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pixelIndex += 4;
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}
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if (write(file,outbuffer,sizeof(uint16_t) * width * height) != sizeof(uint16_t) * width * height) {
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fprintf(stderr,"Could not write image to output file.\n");
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}
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close(file);
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return 0;
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}
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