neatvnc/src/pngfb.c

96 lines
2.2 KiB
C

/*
* This is not a part of the library. It's only used in tests, examples and
* benchmarks.
*/
#include "util.h"
#include "neatvnc.h"
#include <stdlib.h>
#include <stdio.h>
#include <png.h>
#include <stdint.h>
#include <assert.h>
#include <libdrm/drm_fourcc.h>
struct nvnc_fb* read_png_file(const char* filename)
{
int width, height;
png_byte color_type;
png_byte bit_depth;
png_bytep* row_pointers = NULL;
FILE* fp = fopen(filename, "rb");
png_structp png =
png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png)
abort();
png_infop info = png_create_info_struct(png);
if (!info)
abort();
if (setjmp(png_jmpbuf(png)))
abort();
png_init_io(png, fp);
png_read_info(png, info);
width = png_get_image_width(png, info);
height = png_get_image_height(png, info);
color_type = png_get_color_type(png, info);
bit_depth = png_get_bit_depth(png, info);
// Read any color_type into 8bit depth, RGBA format.
// See http://www.libpng.org/pub/png/libpng-manual.txt
if (bit_depth == 16)
png_set_strip_16(png);
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_palette_to_rgb(png);
// PNG_COLOR_TYPE_GRAY_ALPHA is always 8 or 16bit depth.
if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
png_set_expand_gray_1_2_4_to_8(png);
if (png_get_valid(png, info, PNG_INFO_tRNS))
png_set_tRNS_to_alpha(png);
// These color_type don't have an alpha channel then fill it with 0xff.
if (color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_GRAY ||
color_type == PNG_COLOR_TYPE_PALETTE)
png_set_filler(png, 0xFF, PNG_FILLER_AFTER);
if (color_type == PNG_COLOR_TYPE_GRAY ||
color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
png_set_gray_to_rgb(png);
png_read_update_info(png, info);
size_t row_bytes = png_get_rowbytes(png, info);
assert(row_bytes == width * 4);
struct nvnc_fb* fb = nvnc_fb_new(width, height, DRM_FORMAT_ABGR8888);
assert(fb);
uint8_t* addr = nvnc_fb_get_addr(fb);
row_pointers = malloc(sizeof(png_bytep) * height);
assert(row_pointers);
for (int y = 0; y < height; ++y)
row_pointers[y] = addr + y * row_bytes;
png_read_image(png, row_pointers);
free(row_pointers);
fclose(fp);
png_destroy_read_struct(&png, &info, NULL);
return fb;
}