int gfwx_PngWriteFile(const char* filename, uint8_t* data, uint32_t width, uint32_t height, uint32_t bytesPerPixel)
{
int status = -1;
int png_status;
int row_stride;
png_image image;
memset(&image, 0, sizeof(png_image));
image.version = PNG_IMAGE_VERSION;
image.format = (bytesPerPixel == 4) ? PNG_FORMAT_BGRA : PNG_FORMAT_BGR;
image.width = width;
image.height = height;
row_stride = PNG_IMAGE_ROW_STRIDE(image);
png_status = png_image_write_to_file(&image, filename, 0,
(const void*) data, row_stride, NULL);
if (!png_status)
goto exit;
status = 1;
exit:
png_image_free(&image);
return status;
}
int gfwx_PngReadFile(const char* filename, uint8_t** pData, uint32_t* pWidth, uint32_t* pHeight, uint32_t bytesPerPixel)
{
int status = -1;
int png_status;
png_image image;
int row_stride;
uint8_t* buffer = NULL;
memset(&image, 0, sizeof(png_image));
image.version = PNG_IMAGE_VERSION;
png_status = png_image_begin_read_from_file(&image, filename);
if (!png_status)
goto exit;
image.format = (bytesPerPixel == 4) ? PNG_FORMAT_BGRA : PNG_FORMAT_BGR;
row_stride = PNG_IMAGE_ROW_STRIDE(image);
buffer = malloc(PNG_IMAGE_SIZE(image));
if (!buffer)
goto exit;
png_status = png_image_finish_read(&image, NULL, buffer, row_stride, NULL);
if (!png_status)
goto exit;
*pWidth = image.width;
*pHeight = image.height;
*pData = buffer;
status = 1;
exit:
if (status < 1)
free(buffer);
png_image_free(&image);
return status;
}
static int read_png(const char *fname, image *image, gradient *g)
{
int result = 0;
memset(&image->image, 0, sizeof image->image);
image->image.version = PNG_IMAGE_VERSION;
if (png_image_begin_read_from_file(&image->image, image->file_name))
{
image->image.format = PNG_FORMAT_RGBA;
image->stride = PNG_IMAGE_ROW_STRIDE(image->image);
image->buffer = malloc(PNG_IMAGE_SIZE(image->image));
image->pixel_bytes = PNG_IMAGE_PIXEL_SIZE(image->image.format);
if (image->buffer != NULL) {
if(png_image_finish_read(&image->image, NULL /*background*/,
image->buffer, (png_int_32)image->stride,
image->colormap)) {
if(calculate_gradient(image, g))
result = 1;
else
printf("pngtocss: Gradient type not supported\n");
}
else {
fprintf(stderr, "pngtocss: read %s: %s\n", fname,
image->image.message);
png_image_free(&image->image);
}
}
else
fprintf(stderr, "pngtocss: out of memory: %lu bytes\n",
(unsigned long)PNG_IMAGE_SIZE(image->image));
}
else
/* Failed to read the argument: */
fprintf(stderr, "pngtocss: %s: %s\n", fname, image->image.message);
return result;
}
