rtt-f030/rtgui/common/image_png.c

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#include "libpng/png.h"
#include <rtthread.h>
#include <rtgui/image_png.h>
#include <rtgui/rtgui_system.h>
#define PNG_MAGIC_LEN 8
struct rtgui_image_png
{
rt_bool_t is_loaded;
struct rtgui_filerw* filerw;
/* png image information */
png_structp png_ptr;
png_infop info_ptr;
rt_uint8_t *pixels;
};
static rt_bool_t rtgui_image_png_check(struct rtgui_filerw* file);
static rt_bool_t rtgui_image_png_load(struct rtgui_image* image, struct rtgui_filerw* file, rt_bool_t load);
static void rtgui_image_png_unload(struct rtgui_image* image);
static void rtgui_image_png_blit(struct rtgui_image* image, struct rtgui_dc* dc, struct rtgui_rect* rect);
struct rtgui_image_engine rtgui_image_png_engine =
{
"png",
{ RT_NULL },
rtgui_image_png_check,
rtgui_image_png_load,
rtgui_image_png_unload,
rtgui_image_png_blit
};
static void rtgui_image_png_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
{
struct rtgui_filerw* filerw = (struct rtgui_filerw*)png_ptr->io_ptr;
rtgui_filerw_read(filerw, data, length, 1);
}
static rt_bool_t rtgui_image_png_process(png_structp png_ptr, png_infop info_ptr, struct rtgui_image_png* png)
{
int x, y;
png_bytep row;
png_bytep data;
rtgui_color_t *ptr;
row = (png_bytep) rtgui_malloc (png_get_rowbytes(png_ptr, info_ptr));
if (row == RT_NULL) return RT_FALSE;
ptr = (rtgui_color_t *)png->pixels;
switch (info_ptr->color_type)
{
case PNG_COLOR_TYPE_RGBA:
for (y = 0; y < info_ptr->height; y++)
{
png_read_row(png_ptr, row, png_bytep_NULL);
for (x = 0; x < info_ptr->width; x++)
{
data = &(row[x * 4]);
ptr[x+y*info_ptr->width] = RTGUI_ARGB((255 - data[3]), data[0], data[1], data[2]);
}
}
break;
case PNG_COLOR_TYPE_PALETTE:
for (y = 0; y < info_ptr->height; y++)
{
png_read_row(png_ptr, row, png_bytep_NULL);
for (x = 0; x < info_ptr->width; x++)
{
data = &(row[x]);
ptr[x] = RTGUI_ARGB(0, info_ptr->palette[data[0]].red,
info_ptr->palette[data[0]].green,
info_ptr->palette[data[0]].blue);
}
}
default:
break;
};
rtgui_free(row);
return RT_TRUE;
}
static rt_bool_t rtgui_image_png_check(struct rtgui_filerw* file)
{
int start;
rt_bool_t is_PNG;
rt_uint8_t magic[4];
if ( !file ) return 0;
start = rtgui_filerw_tell(file);
/* move to the begining of file */
rtgui_filerw_seek(file, 0, SEEK_SET);
is_PNG = RT_FALSE;
if ( rtgui_filerw_read(file, magic, 1, sizeof(magic)) == sizeof(magic) )
{
if ( magic[0] == 0x89 &&
magic[1] == 'P' &&
magic[2] == 'N' &&
magic[3] == 'G' )
{
is_PNG = RT_TRUE;
}
}
rtgui_filerw_seek(file, start, SEEK_SET);
return(is_PNG);
}
static rt_bool_t rtgui_image_png_load(struct rtgui_image* image, struct rtgui_filerw* file, rt_bool_t load)
{
png_uint_32 width;
png_uint_32 height;
int bit_depth;
int color_type;
double gamma;
struct rtgui_image_png* png;
png = (struct rtgui_image_png*) rtgui_malloc(sizeof(struct rtgui_image_png));
png->png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (png->png_ptr == RT_NULL)
{
rtgui_free(png);
return RT_FALSE;
}
png->info_ptr = png_create_info_struct(png->png_ptr);
if (png->info_ptr == RT_NULL)
{
png_destroy_read_struct(&png->png_ptr, NULL, NULL);
rtgui_free(png);
return RT_FALSE;
}
png->filerw = file;
png_set_read_fn (png->png_ptr, png->filerw, rtgui_image_png_read_data);
png_read_info(png->png_ptr, png->info_ptr);
png_get_IHDR(png->png_ptr, png->info_ptr, &width, &height, &bit_depth,
&color_type, NULL, NULL, NULL);
/* set image information */
image->w = width; image->h = height;
image->engine = &rtgui_image_png_engine;
image->data = png;
if (bit_depth == 16)
png_set_strip_16(png->png_ptr);
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_expand(png->png_ptr);
if (bit_depth < 8)
png_set_expand(png->png_ptr);
if (png_get_valid(png->png_ptr, png->info_ptr, PNG_INFO_tRNS))
png_set_expand(png->png_ptr);
if (color_type == PNG_COLOR_TYPE_GRAY ||
color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
png_set_gray_to_rgb(png->png_ptr);
/* Ignore background color */
/* set gamma conversion */
if (png_get_gAMA(png->png_ptr, png->info_ptr, &gamma))
png_set_gamma(png->png_ptr, (double)2.2, gamma);
png_read_update_info(png->png_ptr, png->info_ptr);
if (load == RT_TRUE)
{
/* load all pixels */
png->pixels = rtgui_malloc(image->w * image->h * sizeof(rtgui_color_t));
if (png->pixels == RT_NULL)
{
png_read_end(png->png_ptr, RT_NULL);
/* destroy png struct */
png_destroy_info_struct(png->png_ptr, &png->info_ptr);
png_destroy_read_struct(&png->png_ptr, RT_NULL, RT_NULL);
/* release data */
rtgui_free(png);
return RT_FALSE;
}
rtgui_image_png_process(png->png_ptr, png->info_ptr, png);
}
else
{
png->pixels = RT_NULL;
}
return RT_TRUE;
}
static void rtgui_image_png_unload(struct rtgui_image* image)
{
struct rtgui_image_png* png;
if (image != RT_NULL)
{
png = (struct rtgui_image_png*) image->data;
png_read_end(png->png_ptr, RT_NULL);
/* destroy png struct */
png_destroy_info_struct(png->png_ptr, &png->info_ptr);
png_destroy_read_struct(&png->png_ptr, RT_NULL, RT_NULL);
if (png->pixels != RT_NULL) rtgui_free(png->pixels);
/* release data */
rtgui_free(png);
}
}
static void rtgui_image_png_blit(struct rtgui_image* image, struct rtgui_dc* dc, struct rtgui_rect* rect)
{
rt_uint16_t x, y, w, h;
rtgui_color_t* ptr;
rtgui_color_t foreground;
struct rtgui_image_png* png;
RT_ASSERT(image != RT_NULL && dc != RT_NULL && rect != RT_NULL);
RT_ASSERT(image->data != RT_NULL);
png = (struct rtgui_image_png*) image->data;
if (image->w < rtgui_rect_width(*rect)) w = image->w;
else w = rtgui_rect_width(*rect);
if (image->h < rtgui_rect_height(*rect)) h = image->h;
else h = rtgui_rect_height(*rect);
/* save foreground color */
foreground = rtgui_dc_get_color(dc);
if (png->pixels != RT_NULL)
{
ptr = (rtgui_color_t*)png->pixels;
/* draw each point within dc */
for (y = 0; y < h; y ++)
{
for (x = 0; x < w; x++)
{
/* not alpha */
if ((*ptr >> 24) != 255)
{
rtgui_dc_set_color(dc, *ptr);
rtgui_dc_draw_point(dc, x + rect->x1, y + rect->y1);
}
/* move to next color buffer */
ptr ++;
}
}
}
else
{
png_bytep row;
png_bytep data;
row = (png_bytep) rtgui_malloc (png_get_rowbytes(png->png_ptr, png->info_ptr));
if (row == RT_NULL) return ;
switch (png->info_ptr->color_type)
{
case PNG_COLOR_TYPE_RGBA:
for (y = 0; y < h; y++)
{
png_read_row(png->png_ptr, row, png_bytep_NULL);
for (x = 0; x < w; x++)
{
data = &(row[x * 4]);
if (data[3] != 0)
{
rtgui_dc_set_color(dc, RTGUI_ARGB((255 - data[3]), data[0], data[1], data[2]));
rtgui_dc_draw_point(dc, x + rect->x1, y + rect->y1);
}
}
}
break;
case PNG_COLOR_TYPE_PALETTE:
for (y = 0; y < h; y++)
{
png_read_row(png->png_ptr, row, png_bytep_NULL);
for (x = 0; x < w; x++)
{
data = &(row[x]);
rtgui_dc_set_color(dc, RTGUI_ARGB(0, png->info_ptr->palette[data[0]].red,
png->info_ptr->palette[data[0]].green,
png->info_ptr->palette[data[0]].blue));
rtgui_dc_draw_point(dc, x + rect->x1, y + rect->y1);
}
}
default:
break;
};
rtgui_free(row);
}
/* restore foreground */
rtgui_dc_set_color(dc, foreground);
}
void rtgui_image_png_init()
{
/* register png on image system */
rtgui_image_register_engine(&rtgui_image_png_engine);
}