pngset.c

/* pngset.c - storage of image information into info struct
 *
 * libpng 1.00
 * For conditions of distribution and use, see copyright notice in png.h
 * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
 * Copyright (c) 1996, 1997 Andreas Dilger
 * Copyright (c) 1998, Glenn Randers-Pehrson
 * March 7, 1998
 *
 * The functions here are used during reads to store data from the file
 * into the info struct, and during writes to store application data
 * into the info struct for writing into the file.  This abstracts the
 * info struct and allows us to change the structure in the future.
 */

#define PNG_INTERNAL
#include "png.h"

#if defined(PNG_READ_bKGD_SUPPORTED) || defined(PNG_WRITE_bKGD_SUPPORTED)
void
png_set_bKGD(png_structp png_ptr, png_infop info_ptr, png_color_16p background)
{
   png_debug1(1, "in %s storage function\n", "bKGD");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   png_memcpy(&(info_ptr->background), background, sizeof(png_color_16));
   info_ptr->valid |= PNG_INFO_bKGD;
}
#endif

#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
void
png_set_cHRM(png_structp png_ptr, png_infop info_ptr,
   double white_x, double white_y, double red_x, double red_y,
   double green_x, double green_y, double blue_x, double blue_y)
{
   png_debug1(1, "in %s storage function\n", "cHRM");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   info_ptr->x_white = (float)white_x;
   info_ptr->y_white = (float)white_y;
   info_ptr->x_red   = (float)red_x;
   info_ptr->y_red   = (float)red_y;
   info_ptr->x_green = (float)green_x;
   info_ptr->y_green = (float)green_y;
   info_ptr->x_blue  = (float)blue_x;
   info_ptr->y_blue  = (float)blue_y;
   info_ptr->valid |= PNG_INFO_cHRM;
}
#endif

#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
void
png_set_gAMA(png_structp png_ptr, png_infop info_ptr, double file_gamma)
{
   png_debug1(1, "in %s storage function\n", "gAMA");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   info_ptr->gamma = (float)file_gamma;
   info_ptr->valid |= PNG_INFO_gAMA;
}
#endif

#if defined(PNG_READ_hIST_SUPPORTED) || defined(PNG_WRITE_hIST_SUPPORTED)
void
png_set_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p hist)
{
   png_debug1(1, "in %s storage function\n", "hIST");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   info_ptr->hist = hist;
   info_ptr->valid |= PNG_INFO_hIST;
}
#endif

void
png_set_IHDR(png_structp png_ptr, png_infop info_ptr,
   png_uint_32 width, png_uint_32 height, int bit_depth,
   int color_type, int interlace_type, int compression_type,
   int filter_type)
{
   int rowbytes_per_pixel;
   png_debug1(1, "in %s storage function\n", "IHDR");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   info_ptr->width = width;
   info_ptr->height = height;
   info_ptr->bit_depth = (png_byte)bit_depth;
   info_ptr->color_type =(png_byte) color_type;
   info_ptr->compression_type = (png_byte)compression_type;
   info_ptr->filter_type = (png_byte)filter_type;
   info_ptr->interlace_type = (png_byte)interlace_type;
   if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
      info_ptr->channels = 1;
   else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
      info_ptr->channels = 3;
   else
      info_ptr->channels = 1;
   if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
      info_ptr->channels++;
   info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);

   /* check for overflow */
   rowbytes_per_pixel = (info_ptr->pixel_depth + 7) >> 3;
   info_ptr->rowbytes = info_ptr->width * rowbytes_per_pixel;
   if (( width > (png_uint_32)2147483647L/rowbytes_per_pixel))
   {
      png_warning(png_ptr,
         "Width too large to process image data; rowbytes will overflow.");
      info_ptr->rowbytes = (png_size_t)0;
   }
}

#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
void
png_set_oFFs(png_structp png_ptr, png_infop info_ptr,
   png_uint_32 offset_x, png_uint_32 offset_y, int unit_type)
{
   png_debug1(1, "in %s storage function\n", "oFFs");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   info_ptr->x_offset = offset_x;
   info_ptr->y_offset = offset_y;
   info_ptr->offset_unit_type = (png_byte)unit_type;
   info_ptr->valid |= PNG_INFO_oFFs;
}
#endif

#if defined(PNG_READ_pCAL_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED)
void
png_set_pCAL(png_structp png_ptr, png_infop info_ptr,
   png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
   png_charp units, png_charpp params)
{
   png_uint_32 length;
   int i;

   png_debug1(1, "in %s storage function\n", "pCAL");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   length = png_strlen(purpose) + 1;
   png_debug1(3, "allocating purpose for info (%d bytes)\n", length);
   info_ptr->pcal_purpose = (png_charp)png_malloc(png_ptr, length);
   png_memcpy(info_ptr->pcal_purpose, purpose, (png_size_t)length);

   png_debug(3, "storing X0, X1, type, and nparams in info\n");
   info_ptr->pcal_X0 = X0;
   info_ptr->pcal_X1 = X1;
   info_ptr->pcal_type = (png_byte)type;
   info_ptr->pcal_nparams = (png_byte)nparams;

   length = png_strlen(units) + 1;
   png_debug1(3, "allocating units for info (%d bytes)\n", length);
   info_ptr->pcal_units = (png_charp)png_malloc(png_ptr, length);
   png_memcpy(info_ptr->pcal_units, units, (png_size_t)length);

   info_ptr->pcal_params = (png_charpp)png_malloc(png_ptr,
      (png_uint_32)((nparams + 1) * sizeof(png_charp)));
   info_ptr->pcal_params[nparams] = NULL;

   for (i = 0; i < nparams; i++)
   {
      length = png_strlen(params[i]) + 1;
      png_debug2(3, "allocating parameter %d for info (%d bytes)\n", i, length);
      info_ptr->pcal_params[i] = (png_charp)png_malloc(png_ptr, length);
      png_memcpy(info_ptr->pcal_params[i], params[i], (png_size_t)length);
   }

   info_ptr->valid |= PNG_INFO_pCAL;
}
#endif

#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
void
png_set_pHYs(png_structp png_ptr, png_infop info_ptr,
   png_uint_32 res_x, png_uint_32 res_y, int unit_type)
{
   png_debug1(1, "in %s storage function\n", "pHYs");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   info_ptr->x_pixels_per_unit = res_x;
   info_ptr->y_pixels_per_unit = res_y;
   info_ptr->phys_unit_type = (png_byte)unit_type;
   info_ptr->valid |= PNG_INFO_pHYs;
}
#endif

void
png_set_PLTE(png_structp png_ptr, png_infop info_ptr,
   png_colorp palette, int num_palette)
{
   png_debug1(1, "in %s storage function\n", "PLTE");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   info_ptr->palette = palette;
   info_ptr->num_palette = (png_uint_16)num_palette;
   info_ptr->valid |= PNG_INFO_PLTE;
}

#if defined(PNG_READ_sBIT_SUPPORTED) || defined(PNG_WRITE_sBIT_SUPPORTED)
void
png_set_sBIT(png_structp png_ptr, png_infop info_ptr,
   png_color_8p sig_bit)
{
   png_debug1(1, "in %s storage function\n", "sBIT");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   png_memcpy(&(info_ptr->sig_bit), sig_bit, sizeof (png_color_8));
   info_ptr->valid |= PNG_INFO_sBIT;
}
#endif

#if defined(PNG_READ_sRGB_SUPPORTED) || defined(PNG_WRITE_sRGB_SUPPORTED)
void
png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int intent)
{
   png_debug1(1, "in %s storage function\n", "sRGB");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   info_ptr->srgb_intent = (png_byte)intent;
   info_ptr->valid |= PNG_INFO_sRGB;
}
void
png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
   int intent)
{
#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
   float file_gamma;
#endif
#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
   float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
#endif
   png_debug1(1, "in %s storage function\n", "sRGB_gAMA_and_cHRM");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   png_set_sRGB(png_ptr, info_ptr, intent);

#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
   file_gamma = (float).45;
   png_set_gAMA(png_ptr, info_ptr, file_gamma);
#endif

#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
   white_x = (float).3127;
   white_y = (float).3290;
   red_x   = (float).64;
   red_y   = (float).33;
   green_x = (float).30;
   green_y = (float).60;
   blue_x  = (float).15;
   blue_y  = (float).06;

   png_set_cHRM(png_ptr, info_ptr,
      white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);

#endif
}
#endif

#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_WRITE_tEXt_SUPPORTED) || \
    defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
void
png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
   int num_text)
{
   int i;

   png_debug1(1, "in %s storage function\n", (png_ptr->chunk_name[0] == '\0' ?
      "text" : (png_const_charp)png_ptr->chunk_name));

   if (png_ptr == NULL || info_ptr == NULL || num_text == 0)
      return;

   /* Make sure we have enough space in the "text" array in info_struct
    * to hold all of the incoming text_ptr objects.
    */
   if (info_ptr->num_text + num_text > info_ptr->max_text)
   {
      if (info_ptr->text != NULL)
      {
         png_textp old_text;
         int old_max;

         old_max = info_ptr->max_text;
         info_ptr->max_text = info_ptr->num_text + num_text + 8;
         old_text = info_ptr->text;
         info_ptr->text = (png_textp)png_malloc(png_ptr,
            (png_uint_32)(info_ptr->max_text * sizeof (png_text)));
         png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max *
            sizeof(png_text)));
         png_free(png_ptr, old_text);
      }
      else
      {
         info_ptr->max_text = num_text + 8;
         info_ptr->num_text = 0;
         info_ptr->text = (png_textp)png_malloc(png_ptr,
            (png_uint_32)(info_ptr->max_text * sizeof (png_text)));
      }
      png_debug1(3, "allocated %d entries for info_ptr->text\n",
         info_ptr->max_text);
   }

   for (i = 0; i < num_text; i++)
   {
      png_textp textp = &(info_ptr->text[info_ptr->num_text]);

      if (text_ptr[i].text == NULL)
         text_ptr[i].text = (png_charp)"";

      if (text_ptr[i].text[0] == '\0')
      {
         textp->text_length = 0;
         textp->compression = PNG_TEXT_COMPRESSION_NONE;
      }
      else
      {
         textp->text_length = png_strlen(text_ptr[i].text);
         textp->compression = text_ptr[i].compression;
      }
      textp->text = text_ptr[i].text;
      textp->key = text_ptr[i].key;
      info_ptr->num_text++;
      png_debug1(3, "transferred text chunk %d\n", info_ptr->num_text);
   }
}
#endif

#if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
void
png_set_tIME(png_structp png_ptr, png_infop info_ptr, png_timep mod_time)
{
   png_debug1(1, "in %s storage function\n", "tIME");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   png_memcpy(&(info_ptr->mod_time), mod_time, sizeof (png_time));
   info_ptr->valid |= PNG_INFO_tIME;
}
#endif

#if defined(PNG_READ_tRNS_SUPPORTED) || defined(PNG_WRITE_tRNS_SUPPORTED)
void
png_set_tRNS(png_structp png_ptr, png_infop info_ptr,
   png_bytep trans, int num_trans, png_color_16p trans_values)
{
   png_debug1(1, "in %s storage function\n", "tRNS");
   if (png_ptr == NULL || info_ptr == NULL)
      return;

   if (trans != NULL)
   {
      info_ptr->trans = trans;
   }

   if (trans_values != NULL)
   {
      png_memcpy(&(info_ptr->trans_values), trans_values,
         sizeof(png_color_16));
      if (num_trans == 0)
        num_trans = 1;
   }
   info_ptr->num_trans = (png_uint_16)num_trans;
   info_ptr->valid |= PNG_INFO_tRNS;
}
#endif