Esempio n. 1
0
static void set_icc(png_structp png_ptr, png_infop info_ptr, const SkImageInfo& info) {
    sk_sp<SkData> icc = icc_from_color_space(info);
    if (!icc) {
        return;
    }

#if PNG_LIBPNG_VER_MAJOR > 1 || (PNG_LIBPNG_VER_MAJOR == 1 && PNG_LIBPNG_VER_MINOR >= 5)
    const char* name = "Skia";
    png_const_bytep iccPtr = icc->bytes();
#else
    SkString str("Skia");
    char* name = str.writable_str();
    png_charp iccPtr = (png_charp) icc->writable_data();
#endif
    png_set_iCCP(png_ptr, info_ptr, name, 0, iccPtr, icc->size());
}
Esempio n. 2
0
    void write_header( const View& view )
    {
        using png_rw_info_t = detail::png_write_support
            <
                typename channel_type<typename get_pixel_type<View>::type>::type,
                typename color_space_type<View>::type
            >;

        // 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
        png_set_IHDR( get_struct()
                    , get_info()
                    , static_cast< png_image_width::type  >( view.width()  )
                    , static_cast< png_image_height::type >( view.height() )
                    , static_cast< png_bitdepth::type     >( png_rw_info_t::_bit_depth )
                    , static_cast< png_color_type::type   >( png_rw_info_t::_color_type )
                    , _info._interlace_method
                    , _info._compression_type
                    , _info._filter_method
                    );

#ifdef BOOST_GIL_IO_PNG_FLOATING_POINT_SUPPORTED
        if( _info._valid_cie_colors )
        {
            png_set_cHRM( get_struct()
                        , get_info()
                        , _info._white_x
                        , _info._white_y
                        , _info._red_x
                        , _info._red_y
                        , _info._green_x
                        , _info._green_y
                        , _info._blue_x
                        , _info._blue_y
                        );
        }

        if( _info._valid_file_gamma )
        {
            png_set_gAMA( get_struct()
                        , get_info()
                        , _info._file_gamma
                        );
        }
#else
        if( _info._valid_cie_colors )
        {
            png_set_cHRM_fixed( get_struct()
                              , get_info()
                              , _info._white_x
                              , _info._white_y
                              , _info._red_x
                              , _info._red_y
                              , _info._green_x
                              , _info._green_y
                              , _info._blue_x
                              , _info._blue_y
                              );
        }

        if( _info._valid_file_gamma )
        {
            png_set_gAMA_fixed( get_struct()
                              , get_info()
                              , _info._file_gamma
                              );
        }
#endif // BOOST_GIL_IO_PNG_FLOATING_POINT_SUPPORTED

        if( _info._valid_icc_profile )
        {
#if PNG_LIBPNG_VER_MINOR >= 5
            png_set_iCCP( get_struct()
                        , get_info()
                        , const_cast< png_charp >( _info._icc_name.c_str() )
                        , _info._iccp_compression_type
                        , reinterpret_cast< png_const_bytep >( & (_info._profile.front ()) )
                        , _info._profile_length
                        );
#else
            png_set_iCCP( get_struct()
                        , get_info()
                        , const_cast< png_charp >( _info._icc_name.c_str() )
                        , _info._iccp_compression_type
                        , const_cast< png_charp >( & (_info._profile.front()) )
                        , _info._profile_length
                        );
#endif
        }

        if( _info._valid_intent )
        {
            png_set_sRGB( get_struct()
                        , get_info()
                        , _info._intent
                        );
        }

        if( _info._valid_palette )
        {
            png_set_PLTE( get_struct()
                        , get_info()
                        , const_cast< png_colorp >( &_info._palette.front() )
                        , _info._num_palette
                        );
        }

        if( _info._valid_background )
        {
            png_set_bKGD( get_struct()
                        , get_info()
                        , const_cast< png_color_16p >( &_info._background )
                        );
        }

        if( _info._valid_histogram )
        {
            png_set_hIST( get_struct()
                        , get_info()
                        , const_cast< png_uint_16p >( &_info._histogram.front() )
                        );
        }

        if( _info._valid_offset )
        {
            png_set_oFFs( get_struct()
                        , get_info()
                        , _info._offset_x
                        , _info._offset_y
                        , _info._off_unit_type
                        );
        }

        if( _info._valid_pixel_calibration )
        {
            std::vector< const char* > params( _info._num_params );
            for( std::size_t i = 0; i < params.size(); ++i )
            {
                params[i] = _info._params[ i ].c_str();
            }

            png_set_pCAL( get_struct()
                        , get_info()
                        , const_cast< png_charp >( _info._purpose.c_str() )
                        , _info._X0
                        , _info._X1
                        , _info._cal_type
                        , _info._num_params
                        , const_cast< png_charp  >( _info._units.c_str() )
                        , const_cast< png_charpp >( &params.front()     )
                        );
        }

        if( _info._valid_resolution )
        {
            png_set_pHYs( get_struct()
                        , get_info()
                        , _info._res_x
                        , _info._res_y
                        , _info._phy_unit_type
                        );
        }

        if( _info._valid_significant_bits )
        {
            png_set_sBIT( get_struct()
                        , get_info()
                        , const_cast< png_color_8p >( &_info._sig_bits )
                        );
        }

#ifndef BOOST_GIL_IO_PNG_1_4_OR_LOWER

#ifdef BOOST_GIL_IO_PNG_FLOATING_POINT_SUPPORTED
        if( _info._valid_scale_factors )
        {
            png_set_sCAL( get_struct()
                        , get_info()
                        , this->_info._scale_unit
                        , this->_info._scale_width
                        , this->_info._scale_height
                        );
        }
#else
#ifdef BOOST_GIL_IO_PNG_FIXED_POINT_SUPPORTED
        if( _info._valid_scale_factors )
        {
            png_set_sCAL_fixed( get_struct()
                              , get_info()
                              , this->_info._scale_unit
                              , this->_info._scale_width
                              , this->_info._scale_height
                              );
        }
#else
        if( _info._valid_scale_factors )
        {
            png_set_sCAL_s( get_struct()
                          , get_info()
                          , this->_info._scale_unit
                          , const_cast< png_charp >( this->_info._scale_width.c_str()  )
                          , const_cast< png_charp >( this->_info._scale_height.c_str() )
                          );
        }

#endif // BOOST_GIL_IO_PNG_FIXED_POINT_SUPPORTED
#endif // BOOST_GIL_IO_PNG_FLOATING_POINT_SUPPORTED
#endif // BOOST_GIL_IO_PNG_1_4_OR_LOWER

        if( _info._valid_text )
        {
            std::vector< png_text > texts( _info._num_text );
            for( std::size_t i = 0; i < texts.size(); ++i )
            {
                png_text pt;
                pt.compression = _info._text[i]._compression;
                pt.key         = const_cast< png_charp >( this->_info._text[i]._key.c_str()  );
                pt.text        = const_cast< png_charp >( this->_info._text[i]._text.c_str() );
                pt.text_length = _info._text[i]._text.length();

                texts[i] = pt;
            }

            png_set_text( get_struct()
                        , get_info()
                        , &texts.front()
                        , _info._num_text
                        );
        }

        if( _info._valid_modification_time )
        {
            png_set_tIME( get_struct()
                        , get_info()
                        , const_cast< png_timep >( &_info._mod_time )
                        );
        }

        if( _info._valid_transparency_factors )
        {
            int sample_max = ( 1u << _info._bit_depth );

            /* libpng doesn't reject a tRNS chunk with out-of-range samples */
            if( !(  (  _info._color_type == PNG_COLOR_TYPE_GRAY
                    && (int) _info._trans_values[0].gray > sample_max
                    )
                 || (  _info._color_type == PNG_COLOR_TYPE_RGB
                    &&(  (int) _info._trans_values[0].red   > sample_max
                      || (int) _info._trans_values[0].green > sample_max
                      || (int) _info._trans_values[0].blue  > sample_max
                      )
                    )
                 )
              )
            {
                //@todo Fix that once reading transparency values works
/*
                png_set_tRNS( get_struct()
                            , get_info()
                            , trans
                            , num_trans
                            , trans_values
                            );
*/
            }
        }

        // Compression Levels - valid values are [0,9]
        png_set_compression_level( get_struct()
                                 , _info._compression_level
                                 );

        png_set_compression_mem_level( get_struct()
                                     , _info._compression_mem_level
                                     );

        png_set_compression_strategy( get_struct()
                                    , _info._compression_strategy
                                    );

        png_set_compression_window_bits( get_struct()
                                       , _info._compression_window_bits
                                       );

        png_set_compression_method( get_struct()
                                  , _info._compression_method
                                  );

        png_set_compression_buffer_size( get_struct()
                                       , _info._compression_buffer_size
                                       );

#ifdef BOOST_GIL_IO_PNG_DITHERING_SUPPORTED
        // Dithering
        if( _info._set_dithering )
        {
            png_set_dither( get_struct()
                          , &_info._dithering_palette.front()
                          , _info._dithering_num_palette
                          , _info._dithering_maximum_colors
                          , &_info._dithering_histogram.front()
                          , _info._full_dither
                          );
        }
#endif // BOOST_GIL_IO_PNG_DITHERING_SUPPORTED

        // Filter
        if( _info._set_filter )
        {
            png_set_filter( get_struct()
                          , 0
                          , _info._filter
                          );
        }

        // Invert Mono
        if( _info._invert_mono )
        {
            png_set_invert_mono( get_struct() );
        }

        // True Bits
        if( _info._set_true_bits )
        {
            png_set_sBIT( get_struct()
                        , get_info()
                        , &_info._true_bits.front()
                        );
        }

        // sRGB Intent
        if( _info._set_srgb_intent )
        {
            png_set_sRGB( get_struct()
                        , get_info()
                        , _info._srgb_intent
                        );
        }

        // Strip Alpha
        if( _info._strip_alpha )
        {
            png_set_strip_alpha( get_struct() );
        }

        // Swap Alpha
        if( _info._swap_alpha )
        {
            png_set_swap_alpha( get_struct() );
        }


        png_write_info( get_struct()
                      , get_info()
                      );
    }
Esempio n. 3
0
static BOOL DLL_CALLCONV
Save(FreeImageIO *io, FIBITMAP *dib, fi_handle handle, int page, int flags, void *data) {
	png_structp png_ptr;
	png_infop info_ptr;
	png_colorp palette = NULL;
	png_uint_32 width, height;
	BOOL has_alpha_channel = FALSE;

	RGBQUAD *pal;					// pointer to dib palette
	int bit_depth, pixel_depth;		// pixel_depth = bit_depth * channels
	int palette_entries;
	int	interlace_type;

	fi_ioStructure fio;
    fio.s_handle = handle;
	fio.s_io = io;

	if ((dib) && (handle)) {
		try {
			// create the chunk manage structure

			png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, (png_voidp)NULL, error_handler, warning_handler);

			if (!png_ptr)  {
				return FALSE;
			}

			// allocate/initialize the image information data.

			info_ptr = png_create_info_struct(png_ptr);

			if (!info_ptr)  {
				png_destroy_write_struct(&png_ptr,  (png_infopp)NULL);
				return FALSE;
			}

			// Set error handling.  REQUIRED if you aren't supplying your own
			// error handling functions in the png_create_write_struct() call.

			if (setjmp(png_jmpbuf(png_ptr)))  {
				// if we get here, we had a problem reading the file

				png_destroy_write_struct(&png_ptr, &info_ptr);

				return FALSE;
			}

			// init the IO
            
			png_set_write_fn(png_ptr, &fio, _WriteProc, _FlushProc);

			// set physical resolution

			png_uint_32 res_x = (png_uint_32)FreeImage_GetDotsPerMeterX(dib);
			png_uint_32 res_y = (png_uint_32)FreeImage_GetDotsPerMeterY(dib);

			if ((res_x > 0) && (res_y > 0))  {
				png_set_pHYs(png_ptr, info_ptr, res_x, res_y, PNG_RESOLUTION_METER);
			}
	
			// 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

			width = FreeImage_GetWidth(dib);
			height = FreeImage_GetHeight(dib);
			pixel_depth = FreeImage_GetBPP(dib);

			BOOL bInterlaced = FALSE;
			if( (flags & PNG_INTERLACED) == PNG_INTERLACED) {
				interlace_type = PNG_INTERLACE_ADAM7;
				bInterlaced = TRUE;
			} else {
				interlace_type = PNG_INTERLACE_NONE;
			}

			// set the ZLIB compression level or default to PNG default compression level (ZLIB level = 6)
			int zlib_level = flags & 0x0F;
			if((zlib_level >= 1) && (zlib_level <= 9)) {
				png_set_compression_level(png_ptr, zlib_level);
			} else if((flags & PNG_Z_NO_COMPRESSION) == PNG_Z_NO_COMPRESSION) {
				png_set_compression_level(png_ptr, Z_NO_COMPRESSION);
			}

			// filtered strategy works better for high color images
			if(pixel_depth >= 16){
				png_set_compression_strategy(png_ptr, Z_FILTERED);
				png_set_filter(png_ptr, 0, PNG_FILTER_NONE|PNG_FILTER_SUB|PNG_FILTER_PAETH);
			} else {
				png_set_compression_strategy(png_ptr, Z_DEFAULT_STRATEGY);
			}

			FREE_IMAGE_TYPE image_type = FreeImage_GetImageType(dib);
			if(image_type == FIT_BITMAP) {
				// standard image type
				bit_depth = (pixel_depth > 8) ? 8 : pixel_depth;
			} else {
				// 16-bit greyscale or 16-bit RGB(A)
				bit_depth = 16;
			}

			switch (FreeImage_GetColorType(dib)) {
				case FIC_MINISWHITE:
					// Invert monochrome files to have 0 as black and 1 as white (no break here)
					png_set_invert_mono(png_ptr);

				case FIC_MINISBLACK:
					png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth, 
						PNG_COLOR_TYPE_GRAY, interlace_type, 
						PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

					break;

				case FIC_PALETTE:
				{
					png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth, 
						PNG_COLOR_TYPE_PALETTE, interlace_type, 
						PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

					// set the palette

					palette_entries = 1 << bit_depth;
					palette = (png_colorp)png_malloc(png_ptr, palette_entries * sizeof (png_color));
					pal = FreeImage_GetPalette(dib);

					for (int i = 0; i < palette_entries; i++) {
						palette[i].red   = pal[i].rgbRed;
						palette[i].green = pal[i].rgbGreen;
						palette[i].blue  = pal[i].rgbBlue;
					}
					
					png_set_PLTE(png_ptr, info_ptr, palette, palette_entries);

					// You must not free palette here, because png_set_PLTE only makes a link to
					// the palette that you malloced.  Wait until you are about to destroy
					// the png structure.

					break;
				}

				case FIC_RGBALPHA :
					has_alpha_channel = TRUE;

					png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth, 
						PNG_COLOR_TYPE_RGBA, interlace_type, 
						PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

#if FREEIMAGE_COLORORDER == FREEIMAGE_COLORORDER_BGR
					// flip BGR pixels to RGB
					if(image_type == FIT_BITMAP) {
						png_set_bgr(png_ptr);
					}
#endif
					break;
	
				case FIC_RGB:
					png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth, 
						PNG_COLOR_TYPE_RGB, interlace_type, 
						PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

#if FREEIMAGE_COLORORDER == FREEIMAGE_COLORORDER_BGR
					// flip BGR pixels to RGB
					if(image_type == FIT_BITMAP) {
						png_set_bgr(png_ptr);
					}
#endif
					break;
					
				case FIC_CMYK:
					break;
			}

			// write possible ICC profile

			FIICCPROFILE *iccProfile = FreeImage_GetICCProfile(dib);
			if (iccProfile->size && iccProfile->data) {
				png_set_iCCP(png_ptr, info_ptr, "Embedded Profile", 0, (png_const_bytep)iccProfile->data, iccProfile->size);
			}

			// write metadata

			WriteMetadata(png_ptr, info_ptr, dib);

			// 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);

			// set the transparency table

			if (FreeImage_IsTransparent(dib) && (FreeImage_GetTransparencyCount(dib) > 0)) {
				png_set_tRNS(png_ptr, info_ptr, FreeImage_GetTransparencyTable(dib), FreeImage_GetTransparencyCount(dib), NULL);
			}

			// set the background color

			if(FreeImage_HasBackgroundColor(dib)) {
				png_color_16 image_background;
				RGBQUAD rgbBkColor;

				FreeImage_GetBackgroundColor(dib, &rgbBkColor);
				memset(&image_background, 0, sizeof(png_color_16));
				image_background.blue  = rgbBkColor.rgbBlue;
				image_background.green = rgbBkColor.rgbGreen;
				image_background.red   = rgbBkColor.rgbRed;
				image_background.index = rgbBkColor.rgbReserved;

				png_set_bKGD(png_ptr, info_ptr, &image_background);
			}
			
			// Write the file header information.

			png_write_info(png_ptr, info_ptr);

			// write out the image data

#ifndef FREEIMAGE_BIGENDIAN
			if (bit_depth == 16) {
				// turn on 16 bit byte swapping
				png_set_swap(png_ptr);
			}
#endif

			int number_passes = 1;
			if (bInterlaced) {
				number_passes = png_set_interlace_handling(png_ptr);
			}

			if ((pixel_depth == 32) && (!has_alpha_channel)) {
				BYTE *buffer = (BYTE *)malloc(width * 3);

				// transparent conversion to 24-bit
				// the number of passes is either 1 for non-interlaced images, or 7 for interlaced images
				for (int pass = 0; pass < number_passes; pass++) {
					for (png_uint_32 k = 0; k < height; k++) {
						FreeImage_ConvertLine32To24(buffer, FreeImage_GetScanLine(dib, height - k - 1), width);			
						png_write_row(png_ptr, buffer);
					}
				}
				free(buffer);
			} else {
				// the number of passes is either 1 for non-interlaced images, or 7 for interlaced images
				for (int pass = 0; pass < number_passes; pass++) {
					for (png_uint_32 k = 0; k < height; k++) {			
						png_write_row(png_ptr, FreeImage_GetScanLine(dib, height - k - 1));					
					}
				}
			}

			// It is REQUIRED to call this to finish writing the rest of the file
			// Bug with png_flush

			png_write_end(png_ptr, info_ptr);

			// clean up after the write, and free any memory allocated
			if (palette) {
				png_free(png_ptr, palette);
			}

			png_destroy_write_struct(&png_ptr, &info_ptr);

			return TRUE;
		} catch (const char *text) {
			FreeImage_OutputMessageProc(s_format_id, text);
		}
	}

	return FALSE;
}
Esempio n. 4
0
static gboolean real_save_png (GdkPixbuf        *pixbuf, 
                               gchar           **keys,
                               gchar           **values,
                               GError          **error,
                               gboolean          to_callback,
                               FILE             *f,
                               GdkPixbufSaveFunc save_func,
                               gpointer          user_data)
{
       png_structp png_ptr = NULL;
       png_infop info_ptr;
       png_textp text_ptr = NULL;
       guchar *ptr;
       guchar *pixels;
       int y;
       int i;
       png_bytep row_ptr;
       png_color_8 sig_bit;
       int w, h, rowstride;
       int has_alpha;
       int bpc;
       int num_keys;
       int compression = -1;
       gboolean success = TRUE;
       guchar *icc_profile = NULL;
       gsize icc_profile_size = 0;
       SaveToFunctionIoPtr to_callback_ioptr;

       num_keys = 0;

       if (keys && *keys) {
               gchar **kiter = keys;
               gchar **viter = values;

               while (*kiter) {
                       if (strncmp (*kiter, "tEXt::", 6) == 0) {
                               gchar  *key = *kiter + 6;
                               int     len = strlen (key);
                               if (len < 1 || len > 79) {
                                       g_set_error_literal (error,
                                                            GDK_PIXBUF_ERROR,
                                                            GDK_PIXBUF_ERROR_BAD_OPTION,
                                                            _("Keys for PNG text chunks must have at least 1 and at most 79 characters."));
                                       success = FALSE;
                                       goto cleanup;
                               }
                               for (i = 0; i < len; i++) {
                                       if ((guchar) key[i] > 127) {
                                               g_set_error_literal (error,
                                                                    GDK_PIXBUF_ERROR,
                                                                    GDK_PIXBUF_ERROR_BAD_OPTION,
                                                                    _("Keys for PNG text chunks must be ASCII characters."));
                                               success = FALSE;
                                               goto cleanup;
                                       }
                               }
                               num_keys++;
                       } else if (strcmp (*kiter, "icc-profile") == 0) {
                               /* decode from base64 */
                               icc_profile = g_base64_decode (*viter, &icc_profile_size);
                               if (icc_profile_size < 127) {
                                       /* This is a user-visible error */
                                       g_set_error (error,
                                                    GDK_PIXBUF_ERROR,
                                                    GDK_PIXBUF_ERROR_BAD_OPTION,
                                                    _("Color profile has invalid length %d."),
                                                    (gint)icc_profile_size);
                                       success = FALSE;
                                       goto cleanup;
                               }
                       } else if (strcmp (*kiter, "compression") == 0) {
                               char *endptr = NULL;
                               compression = strtol (*viter, &endptr, 10);

                               if (endptr == *viter) {
                                       g_set_error (error,
                                                    GDK_PIXBUF_ERROR,
                                                    GDK_PIXBUF_ERROR_BAD_OPTION,
                                                    _("PNG compression level must be a value between 0 and 9; value '%s' could not be parsed."),
                                                    *viter);
                                       success = FALSE;
                                       goto cleanup;
                               }
                               if (compression < 0 || compression > 9) {
                                       /* This is a user-visible error;
                                        * lets people skip the range-checking
                                        * in their app.
                                        */
                                       g_set_error (error,
                                                    GDK_PIXBUF_ERROR,
                                                    GDK_PIXBUF_ERROR_BAD_OPTION,
                                                    _("PNG compression level must be a value between 0 and 9; value '%d' is not allowed."),
                                                    compression);
                                       success = FALSE;
                                       goto cleanup;
                               }
                       } else {
                               g_warning ("Unrecognized parameter (%s) passed to PNG saver.", *kiter);
                       }

                       ++kiter;
                       ++viter;
               }
       }

       if (num_keys > 0) {
               gchar **kiter = keys;
               gchar **viter = values;

               text_ptr = g_new0 (png_text, num_keys);
               for (i = 0; i < num_keys; i++) {
                       if (strncmp (*kiter, "tEXt::", 6) != 0) {
                                kiter++;
                                viter++;
                       }

                       text_ptr[i].compression = PNG_TEXT_COMPRESSION_NONE;
                       text_ptr[i].key  = *kiter + 6;
                       text_ptr[i].text = g_convert (*viter, -1, 
                                                     "ISO-8859-1", "UTF-8", 
                                                     NULL, &text_ptr[i].text_length, 
                                                     NULL);

#ifdef PNG_iTXt_SUPPORTED 
                       if (!text_ptr[i].text) {
                               text_ptr[i].compression = PNG_ITXT_COMPRESSION_NONE;
                               text_ptr[i].text = g_strdup (*viter);
                               text_ptr[i].text_length = 0;
                               text_ptr[i].itxt_length = strlen (text_ptr[i].text);
                               text_ptr[i].lang = NULL;
                               text_ptr[i].lang_key = NULL;
                       }
#endif

                       if (!text_ptr[i].text) {
                               gint j;
                               g_set_error (error,
                                            GDK_PIXBUF_ERROR,
                                            GDK_PIXBUF_ERROR_BAD_OPTION,
                                            _("Value for PNG text chunk %s cannot be converted to ISO-8859-1 encoding."), *kiter + 6);
                               for (j = 0; j < i; j++)
                                       g_free (text_ptr[j].text);
                               g_free (text_ptr);
                               return FALSE;
                       }

                        kiter++;
                        viter++;
               }
       }

       bpc = gdk_pixbuf_get_bits_per_sample (pixbuf);
       w = gdk_pixbuf_get_width (pixbuf);
       h = gdk_pixbuf_get_height (pixbuf);
       rowstride = gdk_pixbuf_get_rowstride (pixbuf);
       has_alpha = gdk_pixbuf_get_has_alpha (pixbuf);
       pixels = gdk_pixbuf_get_pixels (pixbuf);

       png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING,
                                          error,
                                          png_simple_error_callback,
                                          png_simple_warning_callback);
       if (png_ptr == NULL) {
	       success = FALSE;
	       goto cleanup;
       }

       info_ptr = png_create_info_struct (png_ptr);
       if (info_ptr == NULL) {
	       success = FALSE;
	       goto cleanup;
       }
       if (setjmp (png_jmpbuf(png_ptr))) {
	       success = FALSE;
	       goto cleanup;
       }

       if (num_keys > 0) {
               png_set_text (png_ptr, info_ptr, text_ptr, num_keys);
       }

       if (to_callback) {
               to_callback_ioptr.save_func = save_func;
               to_callback_ioptr.user_data = user_data;
               to_callback_ioptr.error = error;
               png_set_write_fn (png_ptr, &to_callback_ioptr,
                                 png_save_to_callback_write_func,
                                 png_save_to_callback_flush_func);
       } else {
               png_init_io (png_ptr, f);
       }

       if (compression >= 0)
               png_set_compression_level (png_ptr, compression);

#if defined(PNG_iCCP_SUPPORTED)
        /* the proper ICC profile title is encoded in the profile */
        if (icc_profile != NULL) {
                png_set_iCCP (png_ptr, info_ptr,
                              "ICC profile", PNG_COMPRESSION_TYPE_BASE,
                              (png_bytep) icc_profile, icc_profile_size);
        }
#endif

       if (has_alpha) {
               png_set_IHDR (png_ptr, info_ptr, w, h, bpc,
                             PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE,
                             PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
       } else {
               png_set_IHDR (png_ptr, info_ptr, w, h, bpc,
                             PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE,
                             PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
       }
       sig_bit.red = bpc;
       sig_bit.green = bpc;
       sig_bit.blue = bpc;
       sig_bit.alpha = bpc;
       png_set_sBIT (png_ptr, info_ptr, &sig_bit);
       png_write_info (png_ptr, info_ptr);
       png_set_shift (png_ptr, &sig_bit);
       png_set_packing (png_ptr);

       ptr = pixels;
       for (y = 0; y < h; y++) {
               row_ptr = (png_bytep)ptr;
               png_write_rows (png_ptr, &row_ptr, 1);
               ptr += rowstride;
       }

       png_write_end (png_ptr, info_ptr);

cleanup:
        if (png_ptr != NULL)
                png_destroy_write_struct (&png_ptr, &info_ptr);

        g_free (icc_profile);

        if (text_ptr != NULL) {
                for (i = 0; i < num_keys; i++)
                        g_free (text_ptr[i].text);
                g_free (text_ptr);
        }

       return success;
}
Esempio n. 5
0
/* Write a VIPS image to PNG.
 */
static int
write_vips( Write *write, 
	int compress, int interlace, const char *profile,
	VipsForeignPngFilter filter, gboolean strip )
{
	VipsImage *in = write->in;

	int bit_depth;
	int color_type;
	int interlace_type;
	int i, nb_passes;

        g_assert( in->BandFmt == VIPS_FORMAT_UCHAR || 
		in->BandFmt == VIPS_FORMAT_USHORT );
	g_assert( in->Coding == VIPS_CODING_NONE );
        g_assert( in->Bands > 0 && in->Bands < 5 );

	/* Catch PNG errors.
	 */
	if( setjmp( png_jmpbuf( write->pPng ) ) ) 
		return( -1 );

	/* Check input image. If we are writing interlaced, we need to make 7
	 * passes over the image. We advertise ourselves as seq, so to ensure
	 * we only suck once from upstream, switch to WIO. 
	 */
	if( interlace ) {
		if( !(write->memory = vips_image_copy_memory( in )) )
			return( -1 );
		in = write->memory;
	}
	else {
		if( vips_image_pio_input( in ) )
			return( -1 );
	}
	if( compress < 0 || compress > 9 ) {
		vips_error( "vips2png", 
			"%s", _( "compress should be in [0,9]" ) );
		return( -1 );
	}

	/* Set compression parameters.
	 */
	png_set_compression_level( write->pPng, compress );

	/* Set row filter.
	 */
	png_set_filter( write->pPng, 0, filter );

	bit_depth = in->BandFmt == VIPS_FORMAT_UCHAR ? 8 : 16;

	switch( in->Bands ) {
	case 1: color_type = PNG_COLOR_TYPE_GRAY; break;
	case 2: color_type = PNG_COLOR_TYPE_GRAY_ALPHA; break;
	case 3: color_type = PNG_COLOR_TYPE_RGB; break;
	case 4: color_type = PNG_COLOR_TYPE_RGB_ALPHA; break;

	default:
		vips_error( "vips2png", 
			_( "can't save %d band image as png" ), in->Bands );
		return( -1 );
	}

	interlace_type = interlace ? PNG_INTERLACE_ADAM7 : PNG_INTERLACE_NONE;

	png_set_IHDR( write->pPng, write->pInfo, 
		in->Xsize, in->Ysize, bit_depth, color_type, interlace_type, 
		PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT );

	/* Set resolution. libpng uses pixels per meter.
	 */
	png_set_pHYs( write->pPng, write->pInfo, 
		VIPS_RINT( in->Xres * 1000 ), VIPS_RINT( in->Yres * 1000 ), 
		PNG_RESOLUTION_METER );

	/* Set ICC Profile.
	 */
	if( profile && 
		!strip ) {
		if( strcmp( profile, "none" ) != 0 ) { 
			void *data;
			size_t length;

			if( !(data = vips__file_read_name( profile, 
				VIPS_ICC_DIR, &length )) ) 
				return( -1 );

#ifdef DEBUG
			printf( "write_vips: "
				"attaching %zd bytes of ICC profile\n",
				length );
#endif /*DEBUG*/

			png_set_iCCP( write->pPng, write->pInfo, "icc", 
				PNG_COMPRESSION_TYPE_BASE, data, length );
		}
	}
	else if( vips_image_get_typeof( in, VIPS_META_ICC_NAME ) &&
		!strip ) {
		void *data;
		size_t length;

		if( vips_image_get_blob( in, VIPS_META_ICC_NAME, 
			&data, &length ) ) 
			return( -1 ); 

#ifdef DEBUG
		printf( "write_vips: attaching %zd bytes of ICC profile\n",
			length );
#endif /*DEBUG*/

		png_set_iCCP( write->pPng, write->pInfo, "icc", 
			PNG_COMPRESSION_TYPE_BASE, data, length );
	}

	png_write_info( write->pPng, write->pInfo ); 

	/* If we're an intel byte order CPU and this is a 16bit image, we need
	 * to swap bytes.
	 */
	if( bit_depth > 8 && !vips_amiMSBfirst() ) 
		png_set_swap( write->pPng ); 

	if( interlace )	
		nb_passes = png_set_interlace_handling( write->pPng );
	else
		nb_passes = 1;

	/* Write data.
	 */
	for( i = 0; i < nb_passes; i++ ) 
		if( vips_sink_disc( in, write_png_block, write ) )
			return( -1 );

	/* The setjmp() was held by our background writer: reset it.
	 */
	if( setjmp( png_jmpbuf( write->pPng ) ) ) 
		return( -1 );

	png_write_end( write->pPng, write->pInfo );

	return( 0 );
}
Esempio n. 6
0
/* Write a VIPS image to PNG.
 */
static int
write_vips( Write *write, int compress, int interlace )
{
	VipsImage *in = write->in;

	int bit_depth;
	int color_type;
	int interlace_type;
	int i, nb_passes;

        g_assert( in->BandFmt == VIPS_FORMAT_UCHAR || 
		in->BandFmt == VIPS_FORMAT_USHORT );
	g_assert( in->Coding == VIPS_CODING_NONE );
        g_assert( in->Bands > 0 && in->Bands < 5 );

	/* Catch PNG errors.
	 */
	if( setjmp( png_jmpbuf( write->pPng ) ) ) 
		return( -1 );

	/* Check input image.
	 */
	if( vips_image_pio_input( in ) )
		return( -1 );
	if( compress < 0 || compress > 9 ) {
		vips_error( "vips2png", 
			"%s", _( "compress should be in [0,9]" ) );
		return( -1 );
	}

	/* Set compression parameters.
	 */
	png_set_compression_level( write->pPng, compress );

	bit_depth = in->BandFmt == VIPS_FORMAT_UCHAR ? 8 : 16;

	switch( in->Bands ) {
	case 1: color_type = PNG_COLOR_TYPE_GRAY; break;
	case 2: color_type = PNG_COLOR_TYPE_GRAY_ALPHA; break;
	case 3: color_type = PNG_COLOR_TYPE_RGB; break;
	case 4: color_type = PNG_COLOR_TYPE_RGB_ALPHA; break;

	default:
		g_assert( 0 );

		/* Keep -Wall happy.
		 */
		return( 0 );
	}

	interlace_type = interlace ? PNG_INTERLACE_ADAM7 : PNG_INTERLACE_NONE;

	png_set_IHDR( write->pPng, write->pInfo, 
		in->Xsize, in->Ysize, bit_depth, color_type, interlace_type, 
		PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT );

	/* Set resolution. libpnbg uses pixels per meter.
	 */
	png_set_pHYs( write->pPng, write->pInfo, 
		VIPS_RINT( in->Xres * 1000 ), VIPS_RINT( in->Yres * 1000 ), 
		PNG_RESOLUTION_METER );

	/* Set ICC Profile.
	 */
	if( vips_image_get_typeof( in, VIPS_META_ICC_NAME ) ) {
		void *profile;
		size_t profile_length;

		if( vips_image_get_blob( in, VIPS_META_ICC_NAME, 
			&profile, &profile_length ) ) 
			return( -1 ); 

#ifdef DEBUG
		printf( "write_vips: attaching %zd bytes of ICC profile\n",
			profile_length );
#endif /*DEBUG*/

		png_set_iCCP( write->pPng, write->pInfo, "icc", 
			PNG_COMPRESSION_TYPE_BASE, profile, profile_length );
	}

	png_write_info( write->pPng, write->pInfo ); 

	/* If we're an intel byte order CPU and this is a 16bit image, we need
	 * to swap bytes.
	 */
	if( bit_depth > 8 && !vips_amiMSBfirst() ) 
		png_set_swap( write->pPng ); 

	if( interlace )	
		nb_passes = png_set_interlace_handling( write->pPng );
	else
		nb_passes = 1;

	/* Write data.
	 */
	for( i = 0; i < nb_passes; i++ ) 
		if( vips_sink_disc( write->in, write_png_block, write ) )
			return( -1 );

	/* The setjmp() was held by our background writer: reset it.
	 */
	if( setjmp( png_jmpbuf( write->pPng ) ) ) 
		return( -1 );

	png_write_end( write->pPng, write->pInfo );

	return( 0 );
}
Esempio n. 7
0
bool KPWriteImage::write2PNG(const QString& destPath)
{
    FILE* file = fopen(QFile::encodeName(destPath), "wb");
    if (!file)
    {
        kDebug( 51000 ) << "Failed to open PNG file for writing" << endl;
        return false;
    }

    uchar       *data       = 0;
    int          bitsDepth  = d->sixteenBit ? 16 : 8;
    png_color_8  sig_bit;
    png_bytep    row_ptr;
    png_structp  png_ptr    = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
    png_infop    info_ptr   = png_create_info_struct(png_ptr);
    png_init_io(png_ptr, file);

    if (QSysInfo::ByteOrder == QSysInfo::LittleEndian)      // Intel
        png_set_bgr(png_ptr);
    else                                                    // PPC
        png_set_swap_alpha(png_ptr);

    if (d->hasAlpha)
    {
        png_set_IHDR(png_ptr, info_ptr, d->width, d->height, bitsDepth,
                     PNG_COLOR_TYPE_RGB_ALPHA,  PNG_INTERLACE_NONE,
                     PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

        if (d->sixteenBit)
            data = new uchar[d->width * 8 * sizeof(uchar)];
        else
            data = new uchar[d->width * 4 * sizeof(uchar)];
    }
    else
    {
        png_set_IHDR(png_ptr, info_ptr, d->width, d->height, bitsDepth,
                     PNG_COLOR_TYPE_RGB,        PNG_INTERLACE_NONE,
                     PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

        if (d->sixteenBit)
            data = new uchar[d->width * 6 * sizeof(uchar)];
        else
            data = new uchar[d->width * 3 * sizeof(uchar)];
    }

    sig_bit.red   = bitsDepth;
    sig_bit.green = bitsDepth;
    sig_bit.blue  = bitsDepth;
    sig_bit.alpha = bitsDepth;
    png_set_sBIT(png_ptr, info_ptr, &sig_bit);
    png_set_compression_level(png_ptr, 9);

    // Write ICC profil.
    if (!d->iccProfile.isEmpty())
    {
        png_set_iCCP(png_ptr, info_ptr, (png_charp)"icc", PNG_COMPRESSION_TYPE_BASE,
                     d->iccProfile.data(), d->iccProfile.size());
    }

    // Write Software info.
    QString libpngver(PNG_HEADER_VERSION_STRING);
    libpngver.replace('\n', ' ');
    QString soft = d->kipipluginsVer;
    soft.append(QString(" (%1)").arg(libpngver));
    png_text text;
    text.key  = (png_charp)"Software";
    text.text = soft.toAscii().data();
    text.compression = PNG_TEXT_COMPRESSION_zTXt;
    png_set_text(png_ptr, info_ptr, &(text), 1);

    // Store Exif data.
    QByteArray ba = d->metadata.getExif(true);
    writeRawProfile(png_ptr, info_ptr, (png_charp)"exif", ba.data(), (png_uint_32) ba.size());

    // Store Iptc data.
    QByteArray ba2 = d->metadata.getIptc();
    writeRawProfile(png_ptr, info_ptr, (png_charp)"iptc", ba2.data(), (png_uint_32) ba2.size());

    // Store Xmp data.
    QByteArray ba3 = d->metadata.getXmp();
    writeRawProfile(png_ptr, info_ptr, (png_charp)("xmp"), ba3.data(), (png_uint_32) ba3.size());

    png_write_info(png_ptr, info_ptr);
    png_set_shift(png_ptr, &sig_bit);
    png_set_packing(png_ptr);

    uchar* ptr = (uchar*)d->data.data();
    uint   x, y, j;

    for (y = 0; y < d->height; y++)
    {
        if (cancel())
        {
            delete [] data;
            fclose(file);
            png_destroy_write_struct(&png_ptr, (png_infopp) & info_ptr);
            png_destroy_info_struct(png_ptr, (png_infopp) & info_ptr);
            return false;
        }

        j = 0;

        for (x = 0; x < d->width*bytesDepth(); x+=bytesDepth())
        {
            if (d->sixteenBit)
            {
                if (d->hasAlpha)
                {
                    data[j++] = ptr[x+1];  // Blue
                    data[j++] = ptr[ x ];
                    data[j++] = ptr[x+3];  // Green
                    data[j++] = ptr[x+2];
                    data[j++] = ptr[x+5];  // Red
                    data[j++] = ptr[x+4];
                    data[j++] = ptr[x+7];  // Alpha
                    data[j++] = ptr[x+6];
                }
                else
                {
                    data[j++] = ptr[x+1];  // Blue
                    data[j++] = ptr[ x ];
                    data[j++] = ptr[x+3];  // Green
                    data[j++] = ptr[x+2];
                    data[j++] = ptr[x+5];  // Red
                    data[j++] = ptr[x+4];
                }
            }
            else
            {
                if (d->hasAlpha)
                {
                    data[j++] = ptr[ x ];  // Blue
                    data[j++] = ptr[x+1];  // Green
                    data[j++] = ptr[x+2];  // Red
                    data[j++] = ptr[x+3];  // Alpha
                }
                else
                {
                    data[j++] = ptr[ x ];  // Blue
                    data[j++] = ptr[x+1];  // Green
                    data[j++] = ptr[x+2];  // Red
                }
            }
        }

        row_ptr = (png_bytep) data;

        png_write_rows(png_ptr, &row_ptr, 1);
        ptr += (d->width * bytesDepth());
    }

    delete [] data;

    png_write_end(png_ptr, info_ptr);
    png_destroy_write_struct(&png_ptr, (png_infopp) & info_ptr);
    png_destroy_info_struct(png_ptr, (png_infopp) & info_ptr);
    fclose(file);

    return true;
}
Esempio n. 8
0
/* Write a VIPS image to PNG.
 */
static int
write_vips( Write *write, 
	int compress, int interlace, const char *profile,
	VipsForeignPngFilter filter, gboolean strip,
	gboolean palette, int colours, int Q, double dither )
{
	VipsImage *in = write->in;

	int bit_depth;
	int color_type;
	int interlace_type;
	int i, nb_passes;

        g_assert( in->BandFmt == VIPS_FORMAT_UCHAR || 
		in->BandFmt == VIPS_FORMAT_USHORT );
	g_assert( in->Coding == VIPS_CODING_NONE );
        g_assert( in->Bands > 0 && in->Bands < 5 );

	/* Catch PNG errors.
	 */
	if( setjmp( png_jmpbuf( write->pPng ) ) ) 
		return( -1 );

	/* Check input image. If we are writing interlaced, we need to make 7
	 * passes over the image. We advertise ourselves as seq, so to ensure
	 * we only suck once from upstream, switch to WIO. 
	 */
	if( interlace ) {
		if( !(write->memory = vips_image_copy_memory( in )) )
			return( -1 );
		in = write->memory;
	}
	else {
		if( vips_image_pio_input( in ) )
			return( -1 );
	}
	if( compress < 0 || compress > 9 ) {
		vips_error( "vips2png", 
			"%s", _( "compress should be in [0,9]" ) );
		return( -1 );
	}

	/* Set compression parameters.
	 */
	png_set_compression_level( write->pPng, compress );

	/* Set row filter.
	 */
	png_set_filter( write->pPng, 0, filter );

	bit_depth = in->BandFmt == VIPS_FORMAT_UCHAR ? 8 : 16;

	switch( in->Bands ) {
	case 1: color_type = PNG_COLOR_TYPE_GRAY; break;
	case 2: color_type = PNG_COLOR_TYPE_GRAY_ALPHA; break;
	case 3: color_type = PNG_COLOR_TYPE_RGB; break;
	case 4: color_type = PNG_COLOR_TYPE_RGB_ALPHA; break;

	default:
		vips_error( "vips2png", 
			_( "can't save %d band image as png" ), in->Bands );
		return( -1 );
	}

#ifdef HAVE_IMAGEQUANT
	/* Enable image quantisation to paletted 8bpp PNG if colours is set.
	 */
	if( palette ) {
		g_assert( colours >= 2 && 
			colours <= 256 );
		bit_depth = 8;
		color_type = PNG_COLOR_TYPE_PALETTE;
	}
#else
	if( palette )
		g_warning( "%s",
			_( "ignoring palette (no quantisation support)" ) );
#endif /*HAVE_IMAGEQUANT*/

	interlace_type = interlace ? PNG_INTERLACE_ADAM7 : PNG_INTERLACE_NONE;

	png_set_IHDR( write->pPng, write->pInfo, 
		in->Xsize, in->Ysize, bit_depth, color_type, interlace_type, 
		PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT );

	/* Set resolution. libpng uses pixels per meter.
	 */
	png_set_pHYs( write->pPng, write->pInfo, 
		VIPS_RINT( in->Xres * 1000 ), VIPS_RINT( in->Yres * 1000 ), 
		PNG_RESOLUTION_METER );

	/* Set ICC Profile.
	 */
	if( profile && 
		!strip ) {
		if( strcmp( profile, "none" ) != 0 ) { 
			void *data;
			size_t length;

			if( !(data = vips__file_read_name( profile, 
				vips__icc_dir(), &length )) ) 
				return( -1 );

#ifdef DEBUG
			printf( "write_vips: "
				"attaching %zd bytes of ICC profile\n",
				length );
#endif /*DEBUG*/

			png_set_iCCP( write->pPng, write->pInfo, "icc", 
				PNG_COMPRESSION_TYPE_BASE, data, length );
		}
	}
	else if( vips_image_get_typeof( in, VIPS_META_ICC_NAME ) &&
		!strip ) {
		void *data;
		size_t length;

		if( vips_image_get_blob( in, VIPS_META_ICC_NAME, 
			&data, &length ) ) 
			return( -1 ); 

#ifdef DEBUG
		printf( "write_vips: attaching %zd bytes of ICC profile\n",
			length );
#endif /*DEBUG*/

		png_set_iCCP( write->pPng, write->pInfo, "icc", 
			PNG_COMPRESSION_TYPE_BASE, data, length );
	}

	if( vips_image_get_typeof( in, VIPS_META_XMP_NAME ) ) {
		const char *str;

		if( vips_image_get_string( in, VIPS_META_XMP_NAME, &str ) )
			return( -1 );

		vips__png_set_text( write->pPng, write->pInfo, 
			"XML:com.adobe.xmp", str );
	}

	/* Set any "png-comment-xx-yyy" metadata items.
	 */
	if( vips_image_map( in, 
		write_png_comment, write ) )
		return( -1 );

#ifdef HAVE_IMAGEQUANT
	if( palette ) {
		VipsImage *im_index;
		VipsImage *im_palette;
		int palette_count;
		png_color *png_palette;
		png_byte *png_trans;
		int trans_count;

		if( vips__quantise_image( in, &im_index, &im_palette, 
			colours, Q, dither ) ) 
			return( -1 );

		palette_count = im_palette->Xsize;

		g_assert( palette_count <= PNG_MAX_PALETTE_LENGTH );

		png_palette = (png_color *) png_malloc( write->pPng,
			palette_count * sizeof( png_color ) );
		png_trans = (png_byte *) png_malloc( write->pPng,
			palette_count * sizeof( png_byte ) );
		trans_count = 0;
		for( i = 0; i < palette_count; i++ ) {
			VipsPel *p = (VipsPel *) 
				VIPS_IMAGE_ADDR( im_palette, i, 0 );
			png_color *col = &png_palette[i];

			col->red = p[0];
			col->green = p[1];
			col->blue = p[2];
			png_trans[i] = p[3];
			if( p[3] != 255 )
				trans_count = i + 1;
#ifdef DEBUG
			printf( "write_vips: palette[%d] %d %d %d %d\n",
				i + 1, p[0], p[1], p[2], p[3] );
#endif /*DEBUG*/
		}

#ifdef DEBUG
		printf( "write_vips: attaching %d color palette\n",
			palette_count );
#endif /*DEBUG*/
		png_set_PLTE( write->pPng, write->pInfo, png_palette,
			palette_count );
		if( trans_count ) {
#ifdef DEBUG
			printf( "write_vips: attaching %d alpha values\n",
				trans_count );
#endif /*DEBUG*/
			png_set_tRNS( write->pPng, write->pInfo, png_trans,
				trans_count, NULL );
		}

		png_free( write->pPng, (void *) png_palette );
		png_free( write->pPng, (void *) png_trans );

		VIPS_UNREF( im_palette );

		VIPS_UNREF( write->memory );
		write->memory = im_index;
		in = write->memory;
	}
#endif /*HAVE_IMAGEQUANT*/

	png_write_info( write->pPng, write->pInfo );

	/* If we're an intel byte order CPU and this is a 16bit image, we need
	 * to swap bytes.
	 */
	if( bit_depth > 8 && 
		!vips_amiMSBfirst() ) 
		png_set_swap( write->pPng ); 

	if( interlace )	
		nb_passes = png_set_interlace_handling( write->pPng );
	else
		nb_passes = 1;

	/* Write data.
	 */
	for( i = 0; i < nb_passes; i++ ) 
		if( vips_sink_disc( in, write_png_block, write ) )
			return( -1 );

	/* The setjmp() was held by our background writer: reset it.
	 */
	if( setjmp( png_jmpbuf( write->pPng ) ) ) 
		return( -1 );

	png_write_end( write->pPng, write->pInfo );

	return( 0 );
}