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/* | |
This is an example demonstrating use of libimagequant from C#. | |
This example code can be freely copied under CC0 (public domain) license. | |
*/ | |
using System; | |
using System.Collections.Generic; | |
using System.Runtime.InteropServices; | |
[StructLayout(LayoutKind.Sequential)] | |
struct liq_color | |
{ | |
public byte r, g, b, a; | |
}; | |
[StructLayout(LayoutKind.Sequential)] | |
struct liq_palette | |
{ | |
public int count; | |
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 256)] | |
public liq_color[] entries; | |
}; | |
enum liq_error | |
{ | |
LIQ_OK = 0, | |
LIQ_QUALITY_TOO_LOW = 99, | |
LIQ_VALUE_OUT_OF_RANGE = 100, | |
LIQ_OUT_OF_MEMORY, | |
LIQ_ABORTED, | |
LIQ_BITMAP_NOT_AVAILABLE, | |
LIQ_BUFFER_TOO_SMALL, | |
LIQ_INVALID_POINTER, | |
}; | |
namespace liq | |
{ | |
using liq_attr_ptr = IntPtr; | |
using liq_image_ptr = IntPtr; | |
using liq_result_ptr = IntPtr; | |
using size_t = UIntPtr; | |
class Liq | |
{ | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_attr_ptr liq_attr_create(); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_attr_ptr liq_attr_copy(liq_attr_ptr attr); | |
[DllImport(@"imagequant.dll")] | |
public static extern void liq_attr_destroy(liq_attr_ptr attr); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_error liq_set_max_colors(liq_attr_ptr attr, int colors); | |
[DllImport(@"imagequant.dll")] | |
public static extern int liq_get_max_colors(liq_attr_ptr attr); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_error liq_set_speed(liq_attr_ptr attr, int speed); | |
[DllImport(@"imagequant.dll")] | |
public static extern int liq_get_speed(liq_attr_ptr attr); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_error liq_set_min_opacity(liq_attr_ptr attr, int min); | |
[DllImport(@"imagequant.dll")] | |
public static extern int liq_get_min_opacity(liq_attr_ptr attr); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_error liq_set_min_posterization(liq_attr_ptr attr, int bits); | |
[DllImport(@"imagequant.dll")] | |
public static extern int liq_get_min_posterization(liq_attr_ptr attr); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_error liq_set_quality(liq_attr_ptr attr, int minimum, int maximum); | |
[DllImport(@"imagequant.dll")] | |
public static extern int liq_get_min_quality(liq_attr_ptr attr); | |
[DllImport(@"imagequant.dll")] | |
public static extern int liq_get_max_quality(liq_attr_ptr attr); | |
[DllImport(@"imagequant.dll")] | |
public static extern void liq_set_last_index_transparent(liq_attr_ptr attr, int is_last); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_image_ptr liq_image_create_rgba(liq_attr_ptr attr, [In, MarshalAs(UnmanagedType.LPArray)] byte[] bitmap, int width, int height, double gamma); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_error liq_image_set_memory_ownership(liq_image_ptr image, int ownership_flags); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_error liq_image_add_fixed_color(liq_image_ptr img, liq_color color); | |
[DllImport(@"imagequant.dll")] | |
public static extern int liq_image_get_width(liq_image_ptr img); | |
[DllImport(@"imagequant.dll")] | |
public static extern int liq_image_get_height(liq_image_ptr img); | |
[DllImport(@"imagequant.dll")] | |
public static extern void liq_image_destroy(liq_image_ptr img); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_result_ptr liq_quantize_image(liq_attr_ptr attr, liq_image_ptr input_image); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_error liq_set_dithering_level(liq_result_ptr res, float dither_level); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_error liq_set_output_gamma(liq_result_ptr res, double gamma); | |
[DllImport(@"imagequant.dll")] | |
public static extern double liq_get_output_gamma(liq_result_ptr res); | |
[DllImport(@"imagequant.dll")] | |
public static extern IntPtr liq_get_palette(liq_result_ptr res); | |
[DllImport(@"imagequant.dll")] | |
public static extern liq_error liq_write_remapped_image(liq_result_ptr res, liq_image_ptr input_image, [Out, MarshalAs(UnmanagedType.LPArray)] byte[] buffer, size_t buffer_size); | |
[DllImport(@"imagequant.dll")] | |
public static extern double liq_get_quantization_error(liq_result_ptr res); | |
[DllImport(@"imagequant.dll")] | |
public static extern int liq_get_quantization_quality(liq_result_ptr res); | |
[DllImport(@"imagequant.dll")] | |
public static extern double liq_get_remapping_error(liq_result_ptr res); | |
[DllImport(@"imagequant.dll")] | |
public static extern int liq_get_remapping_quality(liq_result_ptr res); | |
[DllImport(@"imagequant.dll")] | |
public static extern void liq_result_destroy(liq_result_ptr res); | |
[DllImport(@"imagequant.dll")] | |
public static extern int liq_version(); | |
static void Main(string[] args) | |
{ | |
Console.WriteLine("library version: {0}", liq_version()); | |
int width = 3; | |
int height = 1; | |
var attr = liq_attr_create(); | |
if (attr == IntPtr.Zero) throw new Exception("can't create attr"); | |
byte[] bitmap = { // R, G, B, A, R, G, B, A, ... | |
111, 222, 33, 255, | |
255, 0, 255, 255, | |
255, 0, 255, 255, | |
}; | |
var img = liq_image_create_rgba(attr, bitmap, width, height, 0); | |
if (img == IntPtr.Zero) throw new Exception("can't create image"); | |
var res = liq_quantize_image(attr, img); | |
if (res == IntPtr.Zero) throw new Exception("can't quantize image"); | |
var buffer_size = width * height; | |
var remapped = new byte[buffer_size]; | |
var err = liq_write_remapped_image(res, img, remapped, (UIntPtr)buffer_size); | |
if (err != liq_error.LIQ_OK) | |
{ | |
throw new Exception("remapping error"); | |
} | |
Console.WriteLine("first pixel is {0}th palette entry", remapped[0]); | |
liq_palette pal = (liq_palette)Marshal.PtrToStructure(liq_get_palette(res), typeof(liq_palette)); | |
Console.WriteLine("palette entries: {0}; red of first entry: {1}", pal.count, pal.entries[0].r); | |
liq_image_destroy(img); | |
liq_result_destroy(res); | |
liq_attr_destroy(attr); | |
} | |
} | |
} |