/* Read a PNG file. You may want to return an error code if the read
* fails (depending upon the failure). There are two "prototypes" given
* here - one where we are given the filename, and we need to open the
* file, and the other where we are given an open file (possibly with
* some or all of the magic bytes read - see comments above).
*/
#ifdef open_file /* prototype 1 */
void read_png(char *file_name) /* We need to open the file */
{
png_structp png_ptr;
png_infop info_ptr;
unsigned int sig_read = 0;
png_uint_32 width, height;
int bit_depth, color_type, interlace_type;
FILE *fp;
if ((fp = fopen(file_name, "rb")) == NULL)
return (ERROR);
#else no_open_file /* prototype 2 */
void read_png(FILE *fp, unsigned int sig_read) /* File is already open */
{
png_structp png_ptr;
png_infop info_ptr;
png_uint_32 width, height;
int bit_depth, color_type, interlace_type;
#endif no_open_file /* Only use one prototype! */
/* Create and initialize the png_struct with the desired error handler
* functions. If you want to use the default stderr and longjump method,
* you can supply NULL for the last three parameters. We also supply the
* the compiler header file version, so that we know if the application
* was compiled with a compatible version of the library. REQUIRED
*/
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
png_voidp user_error_ptr, user_error_fn, user_warning_fn);
if (png_ptr == NULL)
{
fclose(fp);
return (ERROR);
}
/* Allocate/initialize the memory for image information. REQUIRED. */
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL)
{
fclose(fp);
png_destroy_read_struct(&png_ptr, png_infopp_NULL, png_infopp_NULL);
return (ERROR);
}
/* Set error handling if you are using the setjmp/longjmp method (this is
* the normal method of doing things with libpng). REQUIRED unless you
* set up your own error handlers in the png_create_read_struct() earlier.
*/
if (setjmp(png_jmpbuf(png_ptr)))
{
/* Free all of the memory associated with the png_ptr and info_ptr */
png_destroy_read_struct(&png_ptr, &info_ptr, png_infopp_NULL);
fclose(fp);
/* If we get here, we had a problem reading the file */
return (ERROR);
}
/* One of the following I/O initialization methods is REQUIRED */
#ifdef streams /* PNG file I/O method 1 */
/* Set up the input control if you are using standard C streams */
png_init_io(png_ptr, fp);
#else no_streams /* PNG file I/O method 2 */
/* If you are using replacement read functions, instead of calling
* png_init_io() here you would call:
*/
png_set_read_fn(png_ptr, (void *)user_io_ptr, user_read_fn);
/* where user_io_ptr is a structure you want available to the callbacks */
#endif no_streams /* Use only one I/O method! */
/* If we have already read some of the signature */
png_set_sig_bytes(png_ptr, sig_read);
#ifdef hilevel
/*
* If you have enough memory to read in the entire image at once,
* and you need to specify only transforms that can be controlled
* with one of the PNG_TRANSFORM_* bits (this presently excludes
* dithering, filling, setting background, and doing gamma
* adjustment), then you can read the entire image (including
* pixels) into the info structure with this call:
*/
png_read_png(png_ptr, info_ptr, png_transforms, png_voidp_NULL);
#else
/* OK, you're doing it the hard way, with the lower-level functions */
/* The call to png_read_info() gives us all of the information from the
* PNG file before the first IDAT (image data chunk). REQUIRED
*/
png_read_info(png_ptr, info_ptr);
png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
&interlace_type, int_p_NULL, int_p_NULL);
/* Set up the data transformations you want. Note that these are all
* optional. Only call them if you want/need them. Many of the
* transformations only work on specific types of images, and many
* are mutually exclusive.
*/
/* Tell libpng to strip 16 bit/color files down to 8 bits/color */
png_set_strip_16(png_ptr);
/* Strip alpha bytes from the input data without combining with the
* background (not recommended).
*/
png_set_strip_alpha(png_ptr);
/* Extract multiple pixels with bit depths of 1, 2, and 4 from a single
* byte into separate bytes (useful for paletted and grayscale images).
*/
png_set_packing(png_ptr);
/* Change the order of packed pixels to least significant bit first
* (not useful if you are using png_set_packing). */
png_set_packswap(png_ptr);
/* Expand paletted colors into true RGB triplets */
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_palette_to_rgb(png_ptr);
/* Expand grayscale images to the full 8 bits from 1, 2, or 4 bits/pixel */
if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
png_set_expand_gray_1_2_4_to_8(png_ptr);
/* Expand paletted or RGB images with transparency to full alpha channels
* so the data will be available as RGBA quartets.
*/
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
png_set_tRNS_to_alpha(png_ptr);
/* Set the background color to draw transparent and alpha images over.
* It is possible to set the red, green, and blue components directly
* for paletted images instead of supplying a palette index. Note that
* even if the PNG file supplies a background, you are not required to
* use it - you should use the (solid) application background if it has one.
*/
png_color_16 my_background, *image_background;
if (png_get_bKGD(png_ptr, info_ptr, &image_background))
png_set_background(png_ptr, image_background,
PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
else
png_set_background(png_ptr, &my_background,
PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
/* Some suggestions as to how to get a screen gamma value
*
* Note that screen gamma is the display_exponent, which includes
* the CRT_exponent and any correction for viewing conditions
*/
if (/* We have a user-defined screen gamma value */)
{
screen_gamma = user-defined screen_gamma;
}
/* This is one way that applications share the same screen gamma value */
else if ((gamma_str = getenv("SCREEN_GAMMA")) != NULL)
void PNGAPI
png_read_png(png_structp png_ptr, png_infop info_ptr,
int transforms,
voidp params)
{
int row;
if (png_ptr == NULL)
return;
/* png_read_info() gives us all of the information from the
* PNG file before the first IDAT (image data chunk).
*/
png_read_info(png_ptr, info_ptr);
if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep))
png_error(png_ptr, "Image is too high to process with png_read_png()");
/* -------------- image transformations start here ------------------- */
#ifdef PNG_READ_16_TO_8_SUPPORTED
/* Tell libpng to strip 16 bit/color files down to 8 bits per color.
*/
if (transforms & PNG_TRANSFORM_STRIP_16)
png_set_strip_16(png_ptr);
#endif
#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
/* Strip alpha bytes from the input data without combining with
* the background (not recommended).
*/
if (transforms & PNG_TRANSFORM_STRIP_ALPHA)
png_set_strip_alpha(png_ptr);
#endif
#if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED)
/* Extract multiple pixels with bit depths of 1, 2, or 4 from a single
* byte into separate bytes (useful for paletted and grayscale images).
*/
if (transforms & PNG_TRANSFORM_PACKING)
png_set_packing(png_ptr);
#endif
#ifdef PNG_READ_PACKSWAP_SUPPORTED
/* Change the order of packed pixels to least significant bit first
* (not useful if you are using png_set_packing).
*/
if (transforms & PNG_TRANSFORM_PACKSWAP)
png_set_packswap(png_ptr);
#endif
#ifdef PNG_READ_EXPAND_SUPPORTED
/* Expand paletted colors into true RGB triplets
* Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel
* Expand paletted or RGB images with transparency to full alpha
* channels so the data will be available as RGBA quartets.
*/
if (transforms & PNG_TRANSFORM_EXPAND)
if ((png_ptr->bit_depth < 8) ||
(png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ||
(png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
png_set_expand(png_ptr);
#endif
/* We don't handle background color or gamma transformation or quantizing.
*/
#ifdef PNG_READ_INVERT_SUPPORTED
/* Invert monochrome files to have 0 as white and 1 as black
*/
if (transforms & PNG_TRANSFORM_INVERT_MONO)
png_set_invert_mono(png_ptr);
#endif
#ifdef PNG_READ_SHIFT_SUPPORTED
/* If you want to shift the pixel values from the range [0,255] or
* [0,65535] to the original [0,7] or [0,31], or whatever range the
* colors were originally in:
*/
if ((transforms & PNG_TRANSFORM_SHIFT)
&& png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
{
png_color_8p sig_bit;
png_get_sBIT(png_ptr, info_ptr, &sig_bit);
png_set_shift(png_ptr, sig_bit);
}
#endif
#ifdef PNG_READ_BGR_SUPPORTED
/* Flip the RGB pixels to BGR (or RGBA to BGRA)
*/
if (transforms & PNG_TRANSFORM_BGR)
png_set_bgr(png_ptr);
#endif
#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
/* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR)
*/
if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
png_set_swap_alpha(png_ptr);
#endif
#ifdef PNG_READ_SWAP_SUPPORTED
/* Swap bytes of 16 bit files to least significant byte first
*/
if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
png_set_swap(png_ptr);
#endif
/* Added at libpng-1.2.41 */
#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
/* Invert the alpha channel from opacity to transparency
*/
if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
png_set_invert_alpha(png_ptr);
#endif
/* Added at libpng-1.2.41 */
#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
/* Expand grayscale image to RGB
*/
if (transforms & PNG_TRANSFORM_GRAY_TO_RGB)
png_set_gray_to_rgb(png_ptr);
#endif
/* We don't handle adding filler bytes */
/* Optional call to gamma correct and add the background to the palette
* and update info structure. REQUIRED if you are expecting libpng to
* update the palette for you (i.e., you selected such a transform above).
*/
png_read_update_info(png_ptr, info_ptr);
/* -------------- image transformations end here ------------------- */
png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
if (info_ptr->row_pointers == NULL)
{
png_uint_32 iptr;
info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr,
info_ptr->height * png_sizeof(png_bytep));
for (iptr=0; iptr<info_ptr->height; iptr++)
info_ptr->row_pointers[iptr] = NULL;
info_ptr->free_me |= PNG_FREE_ROWS;
for (row = 0; row < (int)info_ptr->height; row++)
info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr,
png_get_rowbytes(png_ptr, info_ptr));
}
png_read_image(png_ptr, info_ptr->row_pointers);
info_ptr->valid |= PNG_INFO_IDAT;
/* Read rest of file, and get additional chunks in info_ptr - REQUIRED */
png_read_end(png_ptr, info_ptr);
transforms = transforms; /* Quiet compiler warnings */
params = params;
}
bool PNGImageFileType::write(const Image *OSG_PNG_ARG(pImage ),
std::ostream &OSG_PNG_ARG(os ),
const std::string &OSG_PNG_ARG(mimetype))
{
#ifdef OSG_WITH_PNG
png_structp png_ptr;
png_infop info_ptr;
if(pImage->getDimension() < 1 || pImage->getDimension() > 2)
{
FWARNING(("PNGImageFileType::write: invalid dimension %d!\n",
pImage->getDimension()));
return false;
}
/* Create and initialize the png_struct with the desired error handler
* functions. If you want to use the default stderr and longjump method,
* you can supply NULL for the last three parameters. We also check that
* the library version is compatible with the one used at compile time,
* in case we are using dynamically linked libraries. REQUIRED.
*/
png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
0, &errorOutput, &warningOutput);
if(png_ptr == NULL)
return false;
/* Allocate/initialize the image information data. REQUIRED */
info_ptr = png_create_info_struct(png_ptr);
if(info_ptr == NULL)
{
png_destroy_write_struct(&png_ptr, NULL);
return false;
}
/* set up the output handlers */
png_set_write_fn(png_ptr, &os, &osWriteFunc, &osFlushFunc);
/* This is the hard way */
/* Set the image information here. Width and height are up to 2^31,
* bit_depth is one of 1, 2, 4, 8, or 16, but valid values also depend on
* the color_type selected. color_type is one of PNG_COLOR_TYPE_GRAY,
* PNG_COLOR_TYPE_GRAY_ALPHA, PNG_COLOR_TYPE_PALETTE, PNG_COLOR_TYPE_RGB,
* or PNG_COLOR_TYPE_RGB_ALPHA. interlace is either PNG_INTERLACE_NONE or
* PNG_INTERLACE_ADAM7, and the compression_type and filter_type MUST
* currently be PNG_COMPRESSION_TYPE_BASE and PNG_FILTER_TYPE_BASE. REQUIRED
*/
Int32 ctype;
switch(pImage->getPixelFormat())
{
case Image::OSG_L_PF:
ctype = PNG_COLOR_TYPE_GRAY;
break;
case Image::OSG_LA_PF:
ctype = PNG_COLOR_TYPE_GRAY_ALPHA;
break;
#if defined(GL_BGR) || defined(GL_BGR_EXT)
case Image::OSG_BGR_PF:
#endif
case Image::OSG_RGB_PF:
ctype = PNG_COLOR_TYPE_RGB;
break;
#if defined(GL_BGRA) || defined(GL_BGRA_EXT)
case Image::OSG_BGRA_PF:
#endif
case Image::OSG_RGBA_PF:
ctype = PNG_COLOR_TYPE_RGB_ALPHA;
break;
default:
FWARNING(("PNGImageFileType::write: unknown pixel format %d!\n",
pImage->getPixelFormat()));
png_destroy_write_struct(&png_ptr, NULL);
return false;
}
Int32 bit_depth;
switch(pImage->getDataType())
{
case Image::OSG_UINT8_IMAGEDATA:
bit_depth = 8;
break;
case Image::OSG_UINT16_IMAGEDATA:
bit_depth = 16;
break;
default:
FWARNING (("Invalid pixeldepth, cannot store data\n"));
return false;
};
png_set_IHDR(png_ptr, info_ptr, pImage->getWidth(), pImage->getHeight(),
bit_depth,ctype,
PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_BASE,
PNG_FILTER_TYPE_BASE);
// set resolution png supports only meter per pixel,
// so we do a conversion from dpi with some rounding.
png_uint_32 res_x = png_uint_32(pImage->getResX());
png_uint_32 res_y = png_uint_32(pImage->getResY());
if(pImage->getResUnit() == Image::OSG_RESUNIT_INCH)
{
res_x = png_uint_32((pImage->getResX() * 39.37007874f) < 0.0f ?
(pImage->getResX() * 39.37007874f) - 0.5f :
(pImage->getResX() * 39.37007874f) + 0.5f);
res_y = png_uint_32((pImage->getResY() * 39.37007874f) < 0.0f ?
(pImage->getResY() * 39.37007874f) - 0.5f :
(pImage->getResY() * 39.37007874f) + 0.5f);
}
png_set_pHYs(png_ptr, info_ptr, res_x, res_y,
PNG_RESOLUTION_METER);
#if 0
/* optional significant bit chunk */
/* if we are dealing with a grayscale image then */
sig_bit.gray = true_bit_depth;
/* otherwise, if we are dealing with a color image then */
sig_bit.red = true_red_bit_depth;
sig_bit.green = true_green_bit_depth;
sig_bit.blue = true_blue_bit_depth;
/* if the image has an alpha channel then */
sig_bit.alpha = true_alpha_bit_depth;
png_set_sBIT(png_ptr, info_ptr, sig_bit);
/* Optional gamma chunk is strongly suggested if you have any guess
* as to the correct gamma of the image.
*/
png_set_gAMA(png_ptr, info_ptr, gamma);
/* Optionally write comments into the image */
text_ptr[0].key = "Title";
text_ptr[0].text = "Mona Lisa";
text_ptr[0].compression = PNG_TEXT_COMPRESSION_NONE;
text_ptr[1].key = "Author";
text_ptr[1].text = "Leonardo DaVinci";
text_ptr[1].compression = PNG_TEXT_COMPRESSION_NONE;
text_ptr[2].key = "Description";
text_ptr[2].text = "<long text>";
text_ptr[2].compression = PNG_TEXT_COMPRESSION_zTXt;
#ifdef PNG_iTXt_SUPPORTED
text_ptr[0].lang = NULL;
text_ptr[1].lang = NULL;
text_ptr[2].lang = NULL;
#endif
png_set_text(png_ptr, info_ptr, text_ptr, 3);
#endif
/* other optional chunks like cHRM, bKGD, tRNS, tIME, oFFs, pHYs, */
/* note that if sRGB is present the gAMA and cHRM chunks must be ignored
* on read and must be written in accordance with the sRGB profile */
/* Write the file header information. REQUIRED */
png_write_info(png_ptr, info_ptr);
#if BYTE_ORDER == LITTLE_ENDIAN
if (bit_depth == 16)
png_set_swap(png_ptr);
#endif
#if 0
/* invert monochrome pixels */
png_set_invert_mono(png_ptr);
/* Shift the pixels up to a legal bit depth and fill in
* as appropriate to correctly scale the image.
*/
png_set_shift(png_ptr, &sig_bit);
/* pack pixels into bytes */
png_set_packing(png_ptr);
/* Get rid of filler (OR ALPHA) bytes, pack XRGB/RGBX/ARGB/RGBA into
* RGB (4 channels -> 3 channels). The second parameter is not used.
*/
png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
/* swap bytes of 16-bit files to most significant byte first */
png_set_swap(png_ptr);
/* swap bits of 1, 2, 4 bit packed pixel formats */
png_set_packswap(png_ptr);
#endif
if(pImage->getPixelFormat() == Image::OSG_BGR_PF ||
pImage->getPixelFormat() == Image::OSG_BGRA_PF )
{
/* flip BGR pixels to RGB */
png_set_bgr(png_ptr);
/* swap location of alpha bytes from ARGB to RGBA */
png_set_swap_alpha(png_ptr);
}
/* The easiest way to write the image (you may have a different memory
* layout, however, so choose what fits your needs best). You need to
* use the first method if you aren't handling interlacing yourself.
*/
png_bytep *row_pointers = new png_bytep [pImage->getHeight()];
for(Int32 k = 0; k < pImage->getHeight(); k++)
{
row_pointers[k] =
(const_cast<UInt8 *>(pImage->getData())) +
(pImage->getHeight() - 1 - k) *
pImage->getWidth() * pImage->getBpp();
}
/* write out the entire image data in one call */
png_write_image(png_ptr, row_pointers);
/* It is REQUIRED to call this to finish writing the rest of the file */
png_write_end(png_ptr, info_ptr);
/* clean up after the write, and free any memory allocated */
png_destroy_write_struct(&png_ptr, &info_ptr);
delete [] row_pointers;
/* that's it */
return true;
#else
SWARNING << getMimeType()
<< " write is not compiled into the current binary "
<< endLog;
return false;
#endif
}
cache Png_Create(int width, int height, int numpal, dPalette_t* pal,
int bits, cache data, int lump, int* size)
{
int i = 0;
int x = 0;
int j = 0;
cache image;
cache out;
cache* row_pointers;
png_structp png_ptr;
png_infop info_ptr;
png_colorp palette;
// setup png pointer
png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
if(png_ptr == NULL)
{
WGen_Complain("Png_Create: Failed getting png_ptr");
return NULL;
}
// setup info pointer
info_ptr = png_create_info_struct(png_ptr);
if(info_ptr == NULL)
{
png_destroy_write_struct(&png_ptr, NULL);
WGen_Complain("Png_Create: Failed getting info_ptr");
return NULL;
}
// what does this do again?
if(setjmp(png_jmpbuf(png_ptr)))
{
png_destroy_write_struct(&png_ptr, &info_ptr);
WGen_Complain("Png_Create: Failed on setjmp");
return NULL;
}
// setup custom data writing procedure
png_set_write_fn(png_ptr, NULL, Png_WriteData, NULL);
// setup image
png_set_IHDR(
png_ptr,
info_ptr,
width,
height,
bits,
PNG_COLOR_TYPE_PALETTE,
PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_BASE,
PNG_FILTER_TYPE_DEFAULT);
// setup palette
palette = (png_colorp)Mem_Alloc((16 * numpal) * png_sizeof(png_color));
// copy dPalette_t data over to png_colorp
for(x = 0, j = 0; x < numpal; x++)
{
for(i = 0; i < 16; i++)
{
palette[j].red = pal[j].r;
palette[j].green = pal[j].g;
palette[j].blue = pal[j].b;
j++;
}
}
i = 0;
// add palette to png
png_set_PLTE(png_ptr, info_ptr, palette, (16 * numpal));
// set transparent index
if(palette[0].red == 0 && palette[0].green == 0 && palette[0].blue == 0)
{
char tmp[9];
strncpy(tmp, romWadFile.lump[lump].name, 8);
tmp[0] -= (char)0x80;
tmp[8] = 0;
// Exempt these lumps
if(strcmp(tmp, "FIRE") && /*strcmp(tmp, "USLEGAL") &&
strcmp(tmp, "TITLE") &&*/ strcmp(tmp, "EVIL") &&
/*strcmp(tmp, "IDCRED1") && strcmp(tmp, "WMSCRED1") &&*/
strcmp(tmp, "SPACE") && strcmp(tmp, "CLOUD") &&
strcmp(tmp, "FINAL"))
png_set_tRNS(png_ptr, info_ptr, (png_bytep)&i, 1, NULL);
}
// add png info to data
png_write_info(png_ptr, info_ptr);
// add offset chunk if png is a sprite
if(INSPRITELIST(lump))
{
for(i = 0; i < spriteExCount; i++)
{
if(exSpriteLump[i].lumpRef == lump)
{
int offs[2];
offs[0] = WGen_Swap32(exSpriteLump[i].sprite.offsetx);
offs[1] = WGen_Swap32(exSpriteLump[i].sprite.offsety);
png_write_chunk(png_ptr, "grAb", (byte*)offs, 8);
break;
}
}
}
// setup packing if needed
png_set_packing(png_ptr);
png_set_packswap(png_ptr);
// copy data over
image = data;
row_pointers = (cache*)Mem_Alloc(sizeof(byte*) * height);
for(i = 0; i < height; i++)
{
row_pointers[i] = (cache)Mem_Alloc(width);
if(bits == 4)
{
for(j = 0; j < width; j += 2)
{
row_pointers[i][j] = *image & 0xf;
row_pointers[i][j+1] = *image >> 4;
image++;
}
}
else
{
for(j = 0; j < width; j++)
{
row_pointers[i][j] = *image;
image++;
}
}
png_write_rows(png_ptr, &row_pointers[i], 1);
}
bool Q_INTERNAL_WIN_NO_THROW QPNGImageWriter::writeImage(const QImage& image, volatile int quality_in, const QString &description,
int off_x_in, int off_y_in)
{
QPoint offset = image.offset();
int off_x = off_x_in + offset.x();
int off_y = off_y_in + offset.y();
png_structp png_ptr;
png_infop info_ptr;
png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,0,0,0);
if (!png_ptr) {
return false;
}
png_set_error_fn(png_ptr, 0, 0, qt_png_warning);
info_ptr = png_create_info_struct(png_ptr);
if (!info_ptr) {
png_destroy_write_struct(&png_ptr, 0);
return false;
}
if (setjmp(png_jmpbuf(png_ptr))) {
png_destroy_write_struct(&png_ptr, &info_ptr);
return false;
}
int quality = quality_in;
if (quality >= 0) {
if (quality > 9) {
qWarning("PNG: Quality %d out of range", quality);
quality = 9;
}
png_set_compression_level(png_ptr, quality);
}
png_set_write_fn(png_ptr, (void*)this, qpiw_write_fn, qpiw_flush_fn);
int color_type = 0;
if (image.colorCount()) {
if (image.isGrayscale())
color_type = PNG_COLOR_TYPE_GRAY;
else
color_type = PNG_COLOR_TYPE_PALETTE;
}
else if (image.format() == QImage::Format_Grayscale8)
color_type = PNG_COLOR_TYPE_GRAY;
else if (image.hasAlphaChannel())
color_type = PNG_COLOR_TYPE_RGB_ALPHA;
else
color_type = PNG_COLOR_TYPE_RGB;
png_set_IHDR(png_ptr, info_ptr, image.width(), image.height(),
image.depth() == 1 ? 1 : 8, // per channel
color_type, 0, 0, 0); // sets #channels
if (gamma != 0.0) {
png_set_gAMA(png_ptr, info_ptr, 1.0/gamma);
}
if (image.format() == QImage::Format_MonoLSB)
png_set_packswap(png_ptr);
if (color_type == PNG_COLOR_TYPE_PALETTE) {
// Paletted
int num_palette = qMin(256, image.colorCount());
png_color palette[256];
png_byte trans[256];
int num_trans = 0;
for (int i=0; i<num_palette; i++) {
QRgb rgba=image.color(i);
palette[i].red = qRed(rgba);
palette[i].green = qGreen(rgba);
palette[i].blue = qBlue(rgba);
trans[i] = qAlpha(rgba);
if (trans[i] < 255) {
num_trans = i+1;
}
}
png_set_PLTE(png_ptr, info_ptr, palette, num_palette);
if (num_trans) {
png_set_tRNS(png_ptr, info_ptr, trans, num_trans, 0);
}
}
// Swap ARGB to RGBA (normal PNG format) before saving on
// BigEndian machines
if (QSysInfo::ByteOrder == QSysInfo::BigEndian) {
png_set_swap_alpha(png_ptr);
}
// Qt==ARGB==Big(ARGB)==Little(BGRA). But RGB888 is RGB regardless
if (QSysInfo::ByteOrder == QSysInfo::LittleEndian
&& image.format() != QImage::Format_RGB888) {
png_set_bgr(png_ptr);
}
if (off_x || off_y) {
png_set_oFFs(png_ptr, info_ptr, off_x, off_y, PNG_OFFSET_PIXEL);
}
if (frames_written > 0)
png_set_sig_bytes(png_ptr, 8);
if (image.dotsPerMeterX() > 0 || image.dotsPerMeterY() > 0) {
png_set_pHYs(png_ptr, info_ptr,
image.dotsPerMeterX(), image.dotsPerMeterY(),
PNG_RESOLUTION_METER);
}
set_text(image, png_ptr, info_ptr, description);
png_write_info(png_ptr, info_ptr);
if (image.depth() != 1)
png_set_packing(png_ptr);
if (color_type == PNG_COLOR_TYPE_RGB && image.format() != QImage::Format_RGB888)
png_set_filler(png_ptr, 0,
QSysInfo::ByteOrder == QSysInfo::BigEndian ?
PNG_FILLER_BEFORE : PNG_FILLER_AFTER);
if (looping >= 0 && frames_written == 0) {
uchar data[13] = "NETSCAPE2.0";
// 0123456789aBC
data[0xB] = looping%0x100;
data[0xC] = looping/0x100;
png_write_chunk(png_ptr, const_cast<png_bytep>((const png_byte *)"gIFx"), data, 13);
}
if (ms_delay >= 0 || disposal!=Unspecified) {
uchar data[4];
data[0] = disposal;
data[1] = 0;
data[2] = (ms_delay/10)/0x100; // hundredths
data[3] = (ms_delay/10)%0x100;
png_write_chunk(png_ptr, const_cast<png_bytep>((const png_byte *)"gIFg"), data, 4);
}
int height = image.height();
int width = image.width();
switch (image.format()) {
case QImage::Format_Mono:
case QImage::Format_MonoLSB:
case QImage::Format_Indexed8:
case QImage::Format_Grayscale8:
case QImage::Format_RGB32:
case QImage::Format_ARGB32:
case QImage::Format_RGB888:
{
png_bytep* row_pointers = new png_bytep[height];
for (int y=0; y<height; y++)
row_pointers[y] = const_cast<png_bytep>(image.constScanLine(y));
png_write_image(png_ptr, row_pointers);
delete [] row_pointers;
}
break;
default:
{
QImage::Format fmt = image.hasAlphaChannel() ? QImage::Format_ARGB32 : QImage::Format_RGB32;
QImage row;
png_bytep row_pointers[1];
for (int y=0; y<height; y++) {
row = image.copy(0, y, width, 1).convertToFormat(fmt);
row_pointers[0] = const_cast<png_bytep>(row.constScanLine(0));
png_write_rows(png_ptr, row_pointers, 1);
}
}
break;
}
png_write_end(png_ptr, info_ptr);
frames_written++;
png_destroy_write_struct(&png_ptr, &info_ptr);
return true;
}
int read_PNG(char *file_name)
{
/*
* Took this code from doc/fblib
* and adjusted it to the likings
* of this program.
* ?i
* It is really awesome that a NOOB
* like me, Noisegate can actually
* make useable software on an open
* system like this Linux...
*
* openSOFtWARE rocKS
*/
png_structp png_ptr;
png_infop info_ptr;
unsigned int sig_read = 0;
png_uint_32 _width, _height, row;
int bit_depth, color_type, interlace_type;
FILE *fp;
float screen_gamma;
if ((fp = fopen(file_name, "rb")) == NULL)
return -1;
/* Create and initialize the png_struct with the desired error handler
* functions. If you want to use the default stderr and longjump method,
* you can supply NULL for the last three parameters. We also supply the
* the compiler header file version, so that we know if the application
* was compiled with a compatible version of the library. REQUIRED
*/
//png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, png_voidp user_error_ptr, user_error_fn, user_warning_fn);
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
(png_voidp)NULL,
(png_error_ptr)NULL,
(png_error_ptr)NULL);
if (png_ptr == NULL){
fclose(fp);
return -1;
}
/* Allocate/initialize the memory for image information. REQUIRED. */
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL) {
fclose(fp);
png_destroy_read_struct(&png_ptr, png_infopp_NULL, png_infopp_NULL);
return -1;
}
/* Set error handling if you are using the setjmp/longjmp method (this is
* the normal method of doing things with libpng). REQUIRED unless you
* set up your own error handlers in the png_create_read_struct() earlier.
*/
if (setjmp(png_jmpbuf(png_ptr))) {
/* Free all of the memory associated with the png_ptr and info_ptr */
png_destroy_read_struct(&png_ptr, &info_ptr, png_infopp_NULL);
fclose(fp);
/* If we get here, we had a problem reading the file */
fprintf(stderr, "Error: Couldn't read the file.");
return -1;
}
/* One of the following I/O initialization methods is REQUIRED */
/* Set up the input control if you are using standard C streams */
png_init_io(png_ptr, fp);
/* If we have already read some of the signature */
png_set_sig_bytes(png_ptr, sig_read);
/* OK, you're doing it the hard way, with the lower-level functions */
/* The call to png_read_info() gives us all of the information from the
* PNG file before the first IDAT (image data chunk). REQUIRED
*/
png_read_info(png_ptr, info_ptr);
png_get_IHDR(png_ptr, info_ptr, &_width, &_height, &bit_depth, &color_type,
&interlace_type, int_p_NULL, int_p_NULL);
/* Set up the data transformations you want. Note that these are all
* optional. Only call them if you want/need them. Many of the
* transformations only work on specific types of images, and many
* are mutually exclusive.
*/
/* Tell libpng to strip 16 bit/color files down to 8 bits/color */
png_set_strip_16(png_ptr);
/* Strip alpha bytes from the input data without combining with the
* background (not recommended).
*/
//png_set_strip_alpha(png_ptr);
/* Extract multiple pixels with bit depths of 1, 2, and 4 from a single
* byte into separate bytes (useful for paletted and grayscale images).
*/
png_set_packing(png_ptr);
/* Change the order of packed pixels to least significant bit first
* (not useful if you are using png_set_packing). */
png_set_packswap(png_ptr);
/* Expand paletted colors into true RGB triplets */
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_palette_to_rgb(png_ptr);
/* Expand grayscale images to the full 8 bits from 1, 2, or 4 bits/pixel */
if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
png_set_expand_gray_1_2_4_to_8(png_ptr);
/* Expand paletted or RGB images with transparency to full alpha channels
* so the data will be available as RGBA quartets.
*/
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
png_set_tRNS_to_alpha(png_ptr);
/* Set the background color to draw transparent and alpha images over.
* It is possible to set the red, green, and blue components directly
* for paletted images instead of supplying a palette index. Note that
* even if the PNG file supplies a background, you are not required to
* use it - you should use the (solid) application background if it has one.
*/
png_color_16 my_background, *image_background;
if (png_get_bKGD(png_ptr, info_ptr, &image_background))
png_set_background(png_ptr, image_background,
PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
else
png_set_background(png_ptr, &my_background,
PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
screen_gamma = 1.0;
int intent;
if (png_get_sRGB(png_ptr, info_ptr, &intent))
png_set_gamma(png_ptr, screen_gamma, 0.45455);
else
{
double image_gamma;
if (png_get_gAMA(png_ptr, info_ptr, &image_gamma))
png_set_gamma(png_ptr, screen_gamma, image_gamma);
else
png_set_gamma(png_ptr, screen_gamma, 0.45455);
}
/* Invert monochrome files to have 0 as white and 1 as black */
png_set_invert_mono(png_ptr);
/* If you want to shift the pixel values from the range [0,255] or
* [0,65535] to the original [0,7] or [0,31], or whatever range the
* colors were originally in:
*/
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
{
png_color_8p sig_bit_p;
png_get_sBIT(png_ptr, info_ptr, &sig_bit_p);
png_set_shift(png_ptr, sig_bit_p);
}
/* Flip the RGB pixels to BGR (or RGBA to BGRA) */
if (color_type & PNG_COLOR_MASK_COLOR)
png_set_bgr(png_ptr);
/* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) */
png_set_swap_alpha(png_ptr);
/* Swap bytes of 16 bit files to least significant byte first */
png_set_swap(png_ptr);
/* Add filler (or alpha) byte (before/after each RGB triplet) */
png_set_filler(png_ptr, 0x00, PNG_FILLER_AFTER);
/* Turn on interlace handling. REQUIRED if you are not using
* png_read_image(). To see how to handle interlacing passes,
* see the png_read_row() method below:
*/
//number_passes = png_set_interlace_handling(png_ptr);
/* Optional call to gamma correct and add the background to the palette
* and update info structure. REQUIRED if you are expecting libpng to
* update the palette for you (ie you selected such a transform above).
*/
png_read_update_info(png_ptr, info_ptr);
/* Allocate the memory to hold the image using the fields of info_ptr. */
/* The easiest way to read the image: */
png_bytep row_pointers[_height];
/* Clear the pointer array */
for (row = 0; row < _height; row++)
row_pointers[row] = NULL;
for (row = 0; row < _height; row++)
row_pointers[row] = png_malloc(png_ptr, png_get_rowbytes(png_ptr,
info_ptr));
/* Now it's time to read the image. One of these methods is REQUIRED */
png_read_image(png_ptr, row_pointers);
/* Now mess this rowpointer thing into the tmp_buf
* U dont know if width>_width and height>_height
* so we trunc the guy
*/
int maxY = _height>height?height:_height;
int maxX = _width>width?finfo.line_length:_width;
int pix_offset=0;
for (row=0; row<maxY;row++){
pix_offset = Ox*BPP + ((Oy+row)*finfo.line_length);
memcpy(tmp_buf+pix_offset, row_pointers[row], maxX*BPP);
}
/* Read rest of file, and get additional chunks in info_ptr - REQUIRED */
png_read_end(png_ptr, info_ptr);
/* At this point you have read the entire image */
/* Clean up after the read, and free any memory allocated - REQUIRED */
png_destroy_read_struct(&png_ptr, &info_ptr, png_infopp_NULL);
/* Close the file */
fclose(fp);
//printf("png W x H = %i x %i\n", _width, _height);
/* That's it */
return 0;
}
bool LoadBitmapFromPng( const ResourceLoadingClient& client, const ImageLoader::Input& input, Integration::Bitmap& bitmap )
{
png_structp png = NULL;
png_infop info = NULL;
auto_png autoPng(png, info);
/// @todo: consider parameters
unsigned int y;
unsigned int width, height;
unsigned char *pixels;
png_bytep *rows;
unsigned int bpp = 0; // bytes per pixel
bool valid = false;
// Load info from the header
if( !LoadPngHeader( input.file, width, height, png, info ) )
{
return false;
}
Pixel::Format pixelFormat = Pixel::RGBA8888;
// decide pixel format
unsigned int colordepth = png_get_bit_depth(png, info);
// Ask PNGLib to convert high precision images into something we can use:
if (colordepth == 16)
{
png_set_strip_16(png);
colordepth = 8;
}
png_byte colortype = png_get_color_type(png, info);
if(colortype == PNG_COLOR_TYPE_GRAY)
{
switch( colordepth )
{
case 8:
{
pixelFormat = Pixel::L8;
valid = true;
break;
}
default:
{
break;
}
}
}
else if(colortype == PNG_COLOR_TYPE_GRAY_ALPHA)
{
switch(colordepth)
{
case 8:
{
pixelFormat = Pixel::LA88;
valid = true;
break;
}
default:
{
break;
}
}
}
else if(colortype == PNG_COLOR_TYPE_RGB )
{
switch(colordepth)
{
case 8:
{
pixelFormat = Pixel::RGB888;
valid = true;
break;
}
case 5: /// @todo is this correct for RGB16 5-6-5 ?
{
pixelFormat = Pixel::RGB565;
valid = true;
break;
}
default:
{
break;
}
}
}
else if(colortype == PNG_COLOR_TYPE_RGBA)
{
switch(colordepth)
{
case 8:
{
pixelFormat = Pixel::RGBA8888;
valid = true;
break;
}
default:
{
break;
}
}
}
else if(colortype == PNG_COLOR_TYPE_PALETTE)
{
switch(colordepth)
{
case 2:
case 4:
case 8:
{
/* Expand paletted or RGB images with transparency to full alpha channels
* so the data will be available as RGBA quartets. PNG_INFO_tRNS = 0x10
*/
if(png_get_valid(png, info, PNG_INFO_tRNS) == 0x10)
{
pixelFormat = Pixel::RGBA8888;
valid = true;
}
else
{
pixelFormat = Pixel::RGB888;
png_set_packing(png);
png_set_packswap(png);
png_set_palette_to_rgb(png);
valid = true;
}
break;
}
default:
{
break;
}
}
}
if( !valid )
{
DALI_LOG_WARNING( "Unsupported png format\n" );
return false;
}
// bytes per pixel
bpp = Pixel::GetBytesPerPixel(pixelFormat);
png_read_update_info(png, info);
if(setjmp(png_jmpbuf(png)))
{
DALI_LOG_WARNING("error during png_read_image\n");
return false;
}
unsigned int rowBytes = png_get_rowbytes(png, info);
unsigned int bufferWidth = GetTextureDimension(width);
unsigned int bufferHeight = GetTextureDimension(height);
unsigned int stride = bufferWidth*bpp;
// not sure if this ever happens
if( rowBytes > stride )
{
stride = GetTextureDimension(rowBytes);
bufferWidth = stride / bpp;
}
// decode the whole image into bitmap buffer
pixels = bitmap.GetPackedPixelsProfile()->ReserveBuffer(pixelFormat, width, height, bufferWidth, bufferHeight);
DALI_ASSERT_DEBUG(pixels);
rows = (png_bytep*) malloc(sizeof(png_bytep) * height);
for(y=0; y<height; y++)
{
rows[y] = (png_byte*) (pixels + y * stride);
}
// decode image
png_read_image(png, rows);
free(rows);
return true;
}
void set_packswap() const
{
TRACE_IO_TRANSFORM("png_set_packswap\n");
png_set_packswap(m_png);
}
void PNGAPI
png_read_png(png_structp png_ptr, png_infop info_ptr,
int transforms,
voidp params)
{
int row;
if(png_ptr == NULL) return;
#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
png_set_invert_alpha(png_ptr);
#endif
png_read_info(png_ptr, info_ptr);
if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep))
png_error(png_ptr,"Image is too high to process with png_read_png()");
#if defined(PNG_READ_16_TO_8_SUPPORTED)
if (transforms & PNG_TRANSFORM_STRIP_16)
png_set_strip_16(png_ptr);
#endif
#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
if (transforms & PNG_TRANSFORM_STRIP_ALPHA)
png_set_strip_alpha(png_ptr);
#endif
#if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED)
if (transforms & PNG_TRANSFORM_PACKING)
png_set_packing(png_ptr);
#endif
#if defined(PNG_READ_PACKSWAP_SUPPORTED)
if (transforms & PNG_TRANSFORM_PACKSWAP)
png_set_packswap(png_ptr);
#endif
#if defined(PNG_READ_EXPAND_SUPPORTED)
if (transforms & PNG_TRANSFORM_EXPAND)
if ((png_ptr->bit_depth < 8) ||
(png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ||
(png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
png_set_expand(png_ptr);
#endif
#if defined(PNG_READ_INVERT_SUPPORTED)
if (transforms & PNG_TRANSFORM_INVERT_MONO)
png_set_invert_mono(png_ptr);
#endif
#if defined(PNG_READ_SHIFT_SUPPORTED)
if ((transforms & PNG_TRANSFORM_SHIFT)
&& png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
{
png_color_8p sig_bit;
png_get_sBIT(png_ptr, info_ptr, &sig_bit);
png_set_shift(png_ptr, sig_bit);
}
#endif
#if defined(PNG_READ_BGR_SUPPORTED)
if (transforms & PNG_TRANSFORM_BGR)
png_set_bgr(png_ptr);
#endif
#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
png_set_swap_alpha(png_ptr);
#endif
#if defined(PNG_READ_SWAP_SUPPORTED)
if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
png_set_swap(png_ptr);
#endif
png_read_update_info(png_ptr, info_ptr);
#ifdef PNG_FREE_ME_SUPPORTED
png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
#endif
if(info_ptr->row_pointers == NULL)
{
info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr,
info_ptr->height * png_sizeof(png_bytep));
#ifdef PNG_FREE_ME_SUPPORTED
info_ptr->free_me |= PNG_FREE_ROWS;
#endif
for (row = 0; row < (int)info_ptr->height; row++)
{
info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr,
png_get_rowbytes(png_ptr, info_ptr));
}
}
png_read_image(png_ptr, info_ptr->row_pointers);
info_ptr->valid |= PNG_INFO_IDAT;
png_read_end(png_ptr, info_ptr);
transforms = transforms;
params = params;
}
void initialize()
{
// Now it's time for some transformations.
if( little_endian() )
{
if( this->_info._bit_depth == 16 )
{
// Swap bytes of 16 bit files to least significant byte first.
png_set_swap( this->get()->_struct );
}
if( this->_info._bit_depth < 8 )
{
// swap bits of 1, 2, 4 bit packed pixel formats
png_set_packswap( this->get()->_struct );
}
}
if( this->_info._color_type == PNG_COLOR_TYPE_PALETTE )
{
png_set_palette_to_rgb( this->get()->_struct );
}
if( this->_info._num_trans > 0 )
{
png_set_tRNS_to_alpha( this->get()->_struct );
}
// Tell libpng to handle the gamma conversion for you. The final call
// is a good guess for PC generated images, but it should be configurable
// by the user at run time by the user. It is strongly suggested that
// your application support gamma correction.
if( this->_settings._apply_screen_gamma )
{
// png_set_gamma will change the image data!
#ifdef BOOST_GIL_IO_PNG_FLOATING_POINT_SUPPORTED
png_set_gamma( this->get()->_struct
, this->_settings._screen_gamma
, this->_info._file_gamma
);
#else
png_set_gamma( this->get()->_struct
, this->_settings._screen_gamma
, this->_info._file_gamma
);
#endif // BOOST_GIL_IO_PNG_FLOATING_POINT_SUPPORTED
}
// Interlaced images are not supported.
this->_number_passes = png_set_interlace_handling( this->get()->_struct );
io_error_if( this->_number_passes != 1
, "scanline_read_iterator cannot read interlaced png images."
);
// The above transformation might have changed the bit_depth and color type.
png_read_update_info( this->get()->_struct
, this->get()->_info
);
this->_info._bit_depth = png_get_bit_depth( this->get()->_struct
, this->get()->_info
);
this->_info._num_channels = png_get_channels( this->get()->_struct
, this->get()->_info
);
this->_info._color_type = png_get_color_type( this->get()->_struct
, this->get()->_info
);
this->_scanline_length = png_get_rowbytes( this->get()->_struct
, this->get()->_info
);
}
/* pngReadImage: Reads an image from a memory buffer.
Returns: non-zero if successful.
*/
int pngReadImage(int w, int h, int d, char* bits, char *data, int nBytes) {
png_bytep *row_pointers = NULL;
pngReadState rs;
png_structp png_ptr;
png_infop info_ptr;
png_uint_32 width, height;
int bit_depth, color_type, interlace_type;
DBG("pngReadImage: png_sig_cmp");
/* Compare the first PNG_BYTES_TO_CHECK bytes of the signature. */
if(png_sig_cmp(data, (png_size_t)0, PNG_BYTES_TO_CHECK)) return 0;
DBG("pngReadImage: png_create_read_struct");
/* Create the png_struct */
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (png_ptr == NULL) return 0;
DBG("pngReadImage: png_create_info_struct");
/* Allocate/initialize the image information data. REQUIRED */
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL) {
png_destroy_read_struct(&png_ptr, &info_ptr, png_infopp_NULL);
return 0;
}
/* Set error handling. REQUIRED if you aren't supplying your own
* error handling functions in the png_create_read_struct() call.
*/
if (setjmp(png_jmpbuf(png_ptr))) {
DBG("pngReadImage: triggered png_error");
/* If we get here, we had a problem reading the file */
png_destroy_read_struct(&png_ptr, &info_ptr, png_infopp_NULL);
if(row_pointers) free(row_pointers);
return 0;
}
rs.data = data;
rs.position = 0;
rs.length = nBytes;
png_set_read_fn(png_ptr, (void *)&rs, readBytes);
DBG("pngReadImage: png_read_info");
/* The call to png_read_info() gives us all of the information from the
* PNG file before the first IDAT (image data chunk). REQUIRED
*/
png_read_info(png_ptr, info_ptr);
png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
&interlace_type, int_p_NULL, int_p_NULL);
/* Set up the data transformations you want. Note that these are all
* optional. Only call them if you want/need them. Many of the
* transformations only work on specific types of images, and many
* are mutually exclusive.
*/
/* tell libpng to strip 16 bit/color files down to 8 bits/color */
png_set_strip_16(png_ptr);
/* flip the RGB pixels to BGR (or RGBA to BGRA) */
if (color_type & PNG_COLOR_MASK_COLOR) {
DBG("pngReadImage: png_set_bgr");
png_set_bgr(png_ptr);
}
if(d == 32 && color_type == PNG_COLOR_TYPE_RGB) {
/* Add filler (or alpha) byte (before/after each RGB triplet) */
DBG("pngReadImage: png_set_filler");
png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
}
if(0) {
/* Extract multiple pixels with bit depths of 1, 2, and 4 from a single
* byte into separate bytes (useful for paletted and grayscale images).
*/
png_set_packing(png_ptr);
/* Change the order of packed pixels to least significant bit first
* (not useful if you are using png_set_packing). */
png_set_packswap(png_ptr);
/* Expand paletted colors into true RGB triplets */
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_palette_to_rgb(png_ptr);
}
/* Expand grayscale images to the full 8 bits from 1, 2, or 4 bits/pixel */
if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
png_set_gray_1_2_4_to_8(png_ptr);
/* Expand paletted or RGB images with transparency to full alpha channels
* so the data will be available as RGBA quartets.
*/
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
png_set_tRNS_to_alpha(png_ptr);
if(0) {
/* Set the background color to draw transparent and alpha images over.
* It is possible to set the red, green, and blue components directly
* for paletted images instead of supplying a palette index. Note that
* even if the PNG file supplies a background, you are not required to
* use it - you should use the (solid) application background if it has one
*/
png_color_16 my_background, *image_background;
if (png_get_bKGD(png_ptr, info_ptr, &image_background))
png_set_background(png_ptr, image_background,
PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
else
png_set_background(png_ptr, &my_background,
PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
}
if(0) {
/* Tell libpng to handle the gamma conversion for you. The final call
* is a good guess for PC generated images, but it should be configurable
* by the user at run time by the user. It is strongly suggested that
* your application support gamma correction.
*/
int intent;
double screen_gamma = 1.2;
if (png_get_sRGB(png_ptr, info_ptr, &intent))
png_set_gamma(png_ptr, screen_gamma, 0.45455);
else {
double image_gamma;
if (png_get_gAMA(png_ptr, info_ptr, &image_gamma))
png_set_gamma(png_ptr, screen_gamma, image_gamma);
else
png_set_gamma(png_ptr, screen_gamma, 0.45455);
}
}
if(0) {
/* If you want to shift the pixel values from the range [0,255] or
* [0,65535] to the original [0,7] or [0,31], or whatever range the
* colors were originally in:
*/
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT)) {
png_color_8p sig_bit;
png_get_sBIT(png_ptr, info_ptr, &sig_bit);
png_set_shift(png_ptr, sig_bit);
}
}
if(0) {
/* flip the RGB pixels to BGR (or RGBA to BGRA) */
if (color_type & PNG_COLOR_MASK_COLOR)
png_set_bgr(png_ptr);
/* swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) */
png_set_swap_alpha(png_ptr);
/* swap bytes of 16 bit files to least significant byte first */
png_set_swap(png_ptr);
}
{ /* initialize the png row pointers */
int row, ppw = 32 / d;
int pitch = ((w + ppw - 1) / ppw) * 4;
int rowbytes = png_get_rowbytes(png_ptr, info_ptr);
if(0) {
char info[100];
sprintf(info, "Form pitch: %d\nPNG rowbytes: %d",pitch, rowbytes);
DBG(info);
}
/* XXXX: It seems that this test is pretty pointless; PNG appears
to return the raw rowbytes value, not the padded one.
A better test is probably to compare the w/h/d values
of png with the form values to ensure correctness. */
if(pitch < rowbytes) {
png_error(png_ptr, "Row bytes mismatch");
}
row_pointers = (png_bytep*) calloc(h, sizeof(void*));
for (row = 0; row < h; row++) {
row_pointers[row] = bits + (row*pitch);
}
}
DBG("pngReadImage: png_read_image");
/* Read the entire image in one go */
png_read_image(png_ptr, row_pointers);
DBG("pngReadImage: Cleaning up");
/* clean up after the read, and free any memory allocated - REQUIRED */
png_destroy_read_struct(&png_ptr, &info_ptr, png_infopp_NULL);
if(row_pointers) free(row_pointers);
return 1;
}
