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#include "../include/ImageUtils.hpp"
#include <string.h>
#include <arpa/inet.h>
namespace QuickMedia {
static bool gif_get_size(unsigned char *data, size_t data_size, int *width, int *height) {
if(data_size >= 10 && memcmp(data, "GIF", 3) == 0) {
*width = ((int)data[7] << 8) | data[6];
*height = ((int)data[9] << 8) | data[8];
return true;
}
return false;
}
static bool png_get_size(unsigned char *data, size_t data_size, int *width, int *height) {
if(data_size >= 24 && memcmp(data, "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A", 8) == 0) {
memcpy(width, data + 16, sizeof(int));
memcpy(height, data + 16 + sizeof(int), sizeof(int));
*width = htonl(*width);
*height = htonl(*height);
return true;
}
return false;
}
#if 0
static bool is_cpu_little_endian() {
unsigned short i;
memcpy(&i, "LE", sizeof(i));
return (i & 0xF) == 'E';
}
static unsigned short read_uint16(unsigned char *data, bool cpu_little_endian, bool file_little_endian) {
unsigned short result;
memcpy(&result, data, sizeof(result));
if(cpu_little_endian != file_little_endian)
result = __builtin_bswap16(result);
return result;
}
static unsigned int read_uint32(unsigned char *data, bool cpu_little_endian, bool file_little_endian) {
unsigned int result;
memcpy(&result, data, sizeof(result));
if(cpu_little_endian != file_little_endian)
result = __builtin_bswap32(result);
return result;
}
#endif
#if 0
static bool tiff_get_size(unsigned char *data, size_t data_size, int *width, int *height) {
if(data_size < 8)
return false;
bool cpu_little_endian = is_cpu_little_endian();
bool file_little_endian = true;
if(memcmp(data, "II", 2) == 0)
file_little_endian = true;
else if(memcmp(data, "MM", 2) == 0)
file_little_endian = false;
else
return false;
unsigned short id = read_uint16(data, cpu_little_endian, file_little_endian);
if(id != 42)
return false;
unsigned int offset_to_ifd = read_uint32(data, cpu_little_endian, file_little_endian);
if(offset_to_ifd )
}
#endif
static bool jpeg_get_size(unsigned char *data, size_t data_size, int *width, int *height) {
if(data_size < 11 || memcmp(data, "\xFF\xD8\xFF\xE0", 4) != 0)
return false;
unsigned short block_length = ((int)data[4] << 8) | data[5];
if(memcmp(data + 6, "JFIF\0", 5) != 0)
return false;
size_t index = 4;
while(index < data_size) {
index += block_length;
if(index + 1 >= data_size) return false;
if(data[index] != 0xFF) return false; // Check if start of block
if((data[index + 1] == 0xC0 || data[index + 1] == 0xC2) && index + 8 < data_size) { // Start of frame marker
*height = ((int)data[index + 5] << 8) | data[index + 6];
*width = ((int)data[index + 7] << 8) | data[index + 8];
return true;
} else {
if(index + 2 >= data_size) return false;
index += 2;
block_length = ((int)data[index] << 8) | data[index + 1];
}
}
return false;
}
// TODO: Also support exif files. Exif files are containers for jpeg, tiff etc so once tiff has been implemented so can exif.
// Exif header is similar to jpeg.
bool image_get_resolution(const Path &path, int *width, int *height, ImageType *image_type) {
FILE *file = fopen(path.data.c_str(), "rb");
if(!file)
return false;
unsigned char data[512];
size_t bytes_read = fread(data, 1, sizeof(data), file);
fclose(file);
if(png_get_size(data, bytes_read, width, height)) {
if(image_type)
*image_type = ImageType::PNG;
return true;
} else if(gif_get_size(data, bytes_read, width, height)) {
if(image_type)
*image_type = ImageType::GIF;
return true;
} else if(jpeg_get_size(data, bytes_read, width, height)) {
if(image_type)
*image_type = ImageType::JPG;
return true;
}
return false;
}
}
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