hackthelobby/libcaca/src/common-image.c

289 lines
6.9 KiB
C

/*
* Imaging tools for cacaview and img2irc
* Copyright © 2002—2021 Sam Hocevar <sam@hocevar.net>
* All Rights Reserved
*
* This program is free software. It comes without any warranty, to
* the extent permitted by applicable law. You can redistribute it
* and/or modify it under the terms of the Do What the Fuck You Want
* to Public License, Version 2, as published by the WTFPL Task Force.
* See http://www.wtfpl.net/ for more details.
*/
#include "config.h"
#if !defined(__KERNEL__)
# include <string.h>
# include <stdlib.h>
#endif
#if defined(USE_IMLIB2)
# include <Imlib2.h>
#endif
#include "caca.h"
#include "common-image.h"
#if !defined(USE_IMLIB2)
static unsigned int u32fread(caca_file_t *);
static unsigned int u16fread(caca_file_t *);
static unsigned int u8fread(caca_file_t *);
#endif
struct image * load_image(char const * name)
{
struct image * im = malloc(sizeof(struct image));
unsigned int rmask, gmask, bmask, amask;
#if defined(USE_IMLIB2)
Imlib_Image image;
/* Load the new image */
image = imlib_load_image(name);
if(!image)
{
free(im);
return NULL;
}
imlib_context_set_image(image);
im->pixels = (char *)imlib_image_get_data_for_reading_only();
im->w = imlib_image_get_width();
im->h = imlib_image_get_height();
rmask = 0x00ff0000;
gmask = 0x0000ff00;
bmask = 0x000000ff;
amask = 0xff000000;
uint32_t bpp = 32;
uint32_t depth = 4;
/* Create the libcaca dither */
im->dither = caca_create_dither(bpp, im->w, im->h, depth * im->w,
rmask, gmask, bmask, amask);
if(!im->dither)
{
imlib_free_image();
free(im);
return NULL;
}
im->priv = (void *)image;
#else
/* Try to load a BMP file */
uint32_t red[256], green[256], blue[256], alpha[256];
unsigned int tmp;
caca_file_t *f = caca_file_open(name, "rb");
if (!f)
{
free(im);
return NULL;
}
if (u16fread(f) != 0x4d42)
{
caca_file_close(f);
free(im);
return NULL;
}
u32fread(f); /* size */
u16fread(f); /* reserved 1 */
u16fread(f); /* reserved 2 */
uint32_t offset = u32fread(f);
uint32_t header_size = u32fread(f); /* header size */
im->w = u32fread(f);
im->h = u32fread(f);
uint32_t planes = u16fread(f);
uint32_t bpp = u16fread(f);
uint32_t colors = 0;
/* Sanity check */
if (planes != 1)
{
caca_file_close(f);
free(im);
return NULL;
}
if (header_size == 40)
{
if (u32fread(f) != 0) /* compression */
{
caca_file_close(f);
free(im);
return NULL;
}
u32fread(f); /* sizeimage */
u32fread(f); /* xpelspermeter */
u32fread(f); /* ypelspermeter */
u32fread(f); /* biclrused */
u32fread(f); /* biclrimportantn */
colors = (offset - 54) / 4;
for (uint32_t i = 0; i < colors && i < 256; i++)
{
blue[i] = u8fread(f) * 16;
green[i] = u8fread(f) * 16;
red[i] = u8fread(f) * 16;
alpha[i] = 0;
u8fread(f);
}
}
else if (header_size == 12)
{
colors = (offset - 26) / 3;
for (uint32_t i = 0; i < colors && i < 256; i++)
{
blue[i] = u8fread(f);
green[i] = u8fread(f);
red[i] = u8fread(f);
alpha[i] = 0;
}
}
else
{
caca_file_close(f);
free(im);
return NULL;
}
/* Fill the rest of the palette */
for (uint32_t i = colors; i < 256; i++)
blue[i] = green[i] = red[i] = alpha[i] = 0;
uint32_t depth = (bpp + 7) / 8;
/* Allocate the pixel buffer */
im->pixels = _caca_alloc2d(im->w, im->h, depth);
if (!im->pixels)
{
caca_file_close(f);
free(im);
return NULL;
}
memset(im->pixels, 0, im->w * im->h * depth);
/* Read the bitmap data */
for (size_t y = im->h; y--; )
{
uint32_t bits = 0;
switch (bpp)
{
case 1:
for (size_t x = 0; x < im->w; x++)
{
size_t k = x % 32;
if (k == 0)
bits = u32fread(f);
im->pixels[im->w * y * depth + x] =
(bits >> ((k & ~0xf) + 0xf - (k & 0xf))) & 0x1;
}
break;
case 4:
for (size_t x = 0; x < im->w; x++)
{
size_t k = x % 8;
if (k == 0)
bits = u32fread(f);
im->pixels[im->w * y * depth + x] =
(bits >> (4 * ((k & ~0x1) + 0x1 - (k & 0x1)))) & 0xf;
}
break;
default:
/* Works for 8bpp, but also for 16, 24 etc. */
caca_file_read(f, im->pixels + im->w * y * depth,
im->w * depth);
/* Pad reads to 4 bytes */
tmp = (im->w * depth) % 4;
tmp = (4 - tmp) % 4;
while (tmp--)
u8fread(f);
break;
}
}
switch(depth)
{
case 3:
rmask = 0xff0000;
gmask = 0x00ff00;
bmask = 0x0000ff;
amask = 0x000000;
break;
case 2: /* XXX: those are the 16 bits values */
rmask = 0x7c00;
gmask = 0x03e0;
bmask = 0x001f;
amask = 0x0000;
break;
case 1:
default:
bpp = 8;
rmask = gmask = bmask = amask = 0;
break;
}
caca_file_close(f);
/* Create the libcaca dither */
im->dither = caca_create_dither(bpp, im->w, im->h, depth * im->w,
rmask, gmask, bmask, amask);
if(!im->dither)
{
free(im->pixels);
free(im);
return NULL;
}
if (bpp == 8)
caca_set_dither_palette(im->dither, red, green, blue, alpha);
#endif
return im;
}
void unload_image(struct image * im)
{
#if defined(USE_IMLIB2)
/* Imlib_Image image = (Imlib_Image)im->priv; */
imlib_free_image();
#else
free(im->pixels);
#endif
caca_free_dither(im->dither);
}
#if !defined(USE_IMLIB2)
static unsigned int u32fread(caca_file_t * f)
{
uint8_t buffer[4] = { 0 };
caca_file_read(f, buffer, 4);
return ((unsigned int)buffer[3] << 24) | ((unsigned int)buffer[2] << 16)
| ((unsigned int)buffer[1] << 8) | ((unsigned int)buffer[0]);
}
static unsigned int u16fread(caca_file_t * f)
{
uint8_t buffer[2] = { 0 };
caca_file_read(f, buffer, 2);
return ((unsigned int)buffer[1] << 8) | ((unsigned int)buffer[0]);
}
static unsigned int u8fread(caca_file_t * f)
{
uint8_t buffer[1] = { 0 };
caca_file_read(f, buffer, 1);
return (unsigned int)buffer[0];
}
#endif