/**
* WritePNG(): Write a PNG image.
* @param fImg File handle to save the image to.
* @param w Width of the image.
* @param h Height of the image.
* @param pitch Pitch of the image. (measured in pixels)
* @param screen Pointer to screen buffer.
* @param bpp Bits per pixel.
* @param alpha Alpha channel specification. (32-bit color only.)
* @return 0 on success; non-zero on error.
*/
int ImageUtil::WritePNG(FILE *fImg, const int w, const int h, const int pitch,
const void *screen, const int bpp, const AlphaChannel alpha)
{
if (!fImg || !screen || (w <= 0 || h <= 0 || pitch <= 0))
return 1;
int rval = gsft_png_dll_init();
if (rval)
return rval;
png_structp png_ptr;
png_infop info_ptr;
// Initialize libpng.
png_ptr = ppng_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png_ptr)
{
LOG_MSG(gens, LOG_MSG_LEVEL_CRITICAL,
"Error initializing the PNG pointer.");
return 2;
}
info_ptr = ppng_create_info_struct(png_ptr);
if (!info_ptr)
{
LOG_MSG(gens, LOG_MSG_LEVEL_CRITICAL,
"Error initializing the PNG info pointer.");
ppng_destroy_write_struct(&png_ptr, (png_infopp)NULL);
return 3;
}
if (setjmp(png_jmpbuf(png_ptr)))
{
// TODO: Is setjmp() really necessary?
LOG_MSG(gens, LOG_MSG_LEVEL_CRITICAL,
"Error initializing the PNG setjmp pointer.");
ppng_destroy_write_struct(&png_ptr, &info_ptr);
return 4;
}
// Initialize libpng I/O.
ppng_init_io(png_ptr, fImg);
// Disable PNG filters.
ppng_set_filter(png_ptr, 0, PNG_FILTER_NONE);
// Set the compression level to 5. (Levels range from 1 through 9.)
// TODO: Add a UI option to set compression level.
ppng_set_compression_level(png_ptr, 5);
// Set up the PNG header.
if (!(bpp == 32 && alpha != ALPHACHANNEL_NONE))
{
ppng_set_IHDR(png_ptr, info_ptr, w, h, 8, PNG_COLOR_TYPE_RGB,
PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
PNG_FILTER_TYPE_DEFAULT);
}
else
{
// 32-bit color, with alpha channel.
ppng_set_IHDR(png_ptr, info_ptr, w, h, 8, PNG_COLOR_TYPE_RGB_ALPHA,
PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
PNG_FILTER_TYPE_DEFAULT);
}
// Write the PNG information to the file.
ppng_write_info(png_ptr, info_ptr);
#if GSFT_BYTEORDER == GSFT_LIL_ENDIAN
// PNG stores data in big-endian format.
// On little-endian systems, byteswapping needs to be enabled.
// TODO: Check if this really isn't needed on big-endian systems.
ppng_set_swap(png_ptr);
#endif
// Write the image.
if (bpp == 15)
{
// 15-bit color. (Mode 555)
rval = T_writePNG_rows_16<uint16_t,
MASK_RED_15, MASK_GREEN_15, MASK_BLUE_15,
SHIFT_RED_15, SHIFT_GREEN_15, SHIFT_BLUE_15>
(static_cast<const uint16_t*>(screen), png_ptr, info_ptr, w, h, pitch);
if (rval != 0)
return 5;
}
else if (bpp == 16)
{
// 16-bit color. (Mode 565)
rval = T_writePNG_rows_16<uint16_t,
MASK_RED_16, MASK_GREEN_16, MASK_BLUE_16,
SHIFT_RED_16, SHIFT_GREEN_16, SHIFT_BLUE_16>
(static_cast<const uint16_t*>(screen), png_ptr, info_ptr, w, h, pitch);
if (rval != 0)
return 6;
}
else // if (bpp == 32)
{
// 32-bit color.
// Depending on the alpha channel settings, libpng expects either
// 24-bit data (no alpha) or 32-bit data (with alpha); however,
// libpng offers an option to automatically convert 32-bit data
// without alpha channel to 24-bit. (png_set_filler())
// TODO: PNG_FILLER_AFTER, BGR mode - needed for little-endian.
// Figure out what's needed on big-endian.
png_byte **row_pointers = static_cast<png_byte**>(malloc(sizeof(png_byte*) * h));
uint32_t *screen32 = (uint32_t*)screen;
for (int y = 0; y < h; y++)
{
row_pointers[y] = (uint8_t*)&screen32[y * pitch];
}
if (!alpha)
{
// No alpha channel. Set filler byte.
ppng_set_filler(png_ptr, 0, PNG_FILLER_AFTER);
}
else if (alpha == ALPHACHANNEL_TRANSPARENCY)
{
// Alpha channel indicates transparency.
// 0x00 == opaque; 0xFF == transparent.
ppng_set_invert_alpha(png_ptr);
}
ppng_set_bgr(png_ptr);
ppng_write_rows(png_ptr, row_pointers, h);
free(row_pointers);
}
// Finished writing.
ppng_write_end(png_ptr, info_ptr);
ppng_destroy_write_struct(&png_ptr, &info_ptr);
return 0;
}
static BOOL SaveIconResAsPNG(const BITMAPINFO *pIcon, const char *png_filename, LPCWSTR commentW)
{
static const char comment_key[] = "Created from";
FILE *fp;
png_structp png_ptr;
png_infop info_ptr;
png_text comment;
int nXORWidthBytes, nANDWidthBytes, color_type = 0, i, j;
BYTE *row, *copy = NULL;
const BYTE *pXOR, *pAND = NULL;
int nWidth = pIcon->bmiHeader.biWidth;
int nHeight = pIcon->bmiHeader.biHeight;
int nBpp = pIcon->bmiHeader.biBitCount;
switch (nBpp)
{
case 32:
color_type |= PNG_COLOR_MASK_ALPHA;
/* fall through */
case 24:
color_type |= PNG_COLOR_MASK_COLOR;
break;
default:
return FALSE;
}
if (!libpng_handle && !load_libpng())
{
WINE_WARN("Unable to load libpng\n");
return FALSE;
}
if (!(fp = fopen(png_filename, "w")))
{
WINE_ERR("unable to open '%s' for writing: %s\n", png_filename, strerror(errno));
return FALSE;
}
nXORWidthBytes = 4 * ((nWidth * nBpp + 31) / 32);
nANDWidthBytes = 4 * ((nWidth + 31 ) / 32);
pXOR = (const BYTE*) pIcon + sizeof(BITMAPINFOHEADER) + pIcon->bmiHeader.biClrUsed * sizeof(RGBQUAD);
if (nHeight > nWidth)
{
nHeight /= 2;
pAND = pXOR + nHeight * nXORWidthBytes;
}
/* Apply mask if present */
if (pAND)
{
RGBQUAD bgColor;
/* copy bytes before modifying them */
copy = HeapAlloc( GetProcessHeap(), 0, nHeight * nXORWidthBytes );
memcpy( copy, pXOR, nHeight * nXORWidthBytes );
pXOR = copy;
/* image and mask are upside down reversed */
row = copy + (nHeight - 1) * nXORWidthBytes;
/* top left corner */
bgColor.rgbRed = row[0];
bgColor.rgbGreen = row[1];
bgColor.rgbBlue = row[2];
bgColor.rgbReserved = 0;
for (i = 0; i < nHeight; i++, row -= nXORWidthBytes)
for (j = 0; j < nWidth; j++, row += nBpp >> 3)
if (MASK(j, i))
{
RGBQUAD *pixel = (RGBQUAD *)row;
pixel->rgbBlue = bgColor.rgbBlue;
pixel->rgbGreen = bgColor.rgbGreen;
pixel->rgbRed = bgColor.rgbRed;
if (nBpp == 32)
pixel->rgbReserved = bgColor.rgbReserved;
}
}
comment.text = NULL;
if (!(png_ptr = ppng_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL)) ||
!(info_ptr = ppng_create_info_struct(png_ptr)))
goto error;
if (setjmp(png_jmpbuf(png_ptr)))
{
/* All future errors jump here */
WINE_ERR("png error\n");
goto error;
}
ppng_init_io(png_ptr, fp);
ppng_set_IHDR(png_ptr, info_ptr, nWidth, nHeight, 8,
color_type,
PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_DEFAULT,
PNG_FILTER_TYPE_DEFAULT);
/* Set comment */
comment.compression = PNG_TEXT_COMPRESSION_NONE;
comment.key = (png_charp)comment_key;
i = WideCharToMultiByte(CP_UNIXCP, 0, commentW, -1, NULL, 0, NULL, NULL);
comment.text = HeapAlloc(GetProcessHeap(), 0, i);
WideCharToMultiByte(CP_UNIXCP, 0, commentW, -1, comment.text, i, NULL, NULL);
comment.text_length = i - 1;
ppng_set_text(png_ptr, info_ptr, &comment, 1);
ppng_write_info(png_ptr, info_ptr);
ppng_set_bgr(png_ptr);
for (i = nHeight - 1; i >= 0 ; i--)
ppng_write_row(png_ptr, (png_bytep)pXOR + nXORWidthBytes * i);
ppng_write_end(png_ptr, info_ptr);
ppng_destroy_write_struct(&png_ptr, &info_ptr);
if (png_ptr) ppng_destroy_write_struct(&png_ptr, NULL);
fclose(fp);
HeapFree(GetProcessHeap(), 0, copy);
HeapFree(GetProcessHeap(), 0, comment.text);
return TRUE;
error:
if (png_ptr) ppng_destroy_write_struct(&png_ptr, NULL);
fclose(fp);
unlink(png_filename);
HeapFree(GetProcessHeap(), 0, copy);
HeapFree(GetProcessHeap(), 0, comment.text);
return FALSE;
}
