void PNGAPI
png_write_info(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
int i;
#endif
png_debug(1, "in png_write_info");
if (png_ptr == NULL || info_ptr == NULL)
return;
png_write_info_before_PLTE(png_ptr, info_ptr);
if (info_ptr->valid & PNG_INFO_PLTE)
png_write_PLTE(png_ptr, info_ptr->palette,
(png_uint_32)info_ptr->num_palette);
else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
png_error(png_ptr, "Valid palette required for paletted images");
#ifdef PNG_WRITE_tRNS_SUPPORTED
if (info_ptr->valid & PNG_INFO_tRNS)
{
#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
/* Invert the alpha channel (in tRNS) */
if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&
info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
{
int j;
for (j = 0; j<(int)info_ptr->num_trans; j++)
info_ptr->trans_alpha[j] =
(png_byte)(255 - info_ptr->trans_alpha[j]);
}
#endif
png_write_tRNS(png_ptr, info_ptr->trans_alpha, &(info_ptr->trans_color),
info_ptr->num_trans, info_ptr->color_type);
}
#endif
#ifdef PNG_WRITE_bKGD_SUPPORTED
if (info_ptr->valid & PNG_INFO_bKGD)
png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
#endif
#ifdef PNG_WRITE_hIST_SUPPORTED
if (info_ptr->valid & PNG_INFO_hIST)
png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
#endif
#ifdef PNG_WRITE_oFFs_SUPPORTED
if (info_ptr->valid & PNG_INFO_oFFs)
png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
info_ptr->offset_unit_type);
#endif
#ifdef PNG_WRITE_pCAL_SUPPORTED
if (info_ptr->valid & PNG_INFO_pCAL)
png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
info_ptr->pcal_units, info_ptr->pcal_params);
#endif
#ifdef PNG_WRITE_sCAL_SUPPORTED
if (info_ptr->valid & PNG_INFO_sCAL)
png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,
info_ptr->scal_s_width, info_ptr->scal_s_height);
#endif /* sCAL */
#ifdef PNG_WRITE_pHYs_SUPPORTED
if (info_ptr->valid & PNG_INFO_pHYs)
png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
#endif /* pHYs */
#ifdef PNG_WRITE_tIME_SUPPORTED
if (info_ptr->valid & PNG_INFO_tIME)
{
png_write_tIME(png_ptr, &(info_ptr->mod_time));
png_ptr->mode |= PNG_WROTE_tIME;
}
#endif /* tIME */
#ifdef PNG_WRITE_sPLT_SUPPORTED
if (info_ptr->valid & PNG_INFO_sPLT)
for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
#endif /* sPLT */
#ifdef PNG_WRITE_TEXT_SUPPORTED
/* Check to see if we need to write text chunks */
for (i = 0; i < info_ptr->num_text; i++)
{
png_debug2(2, "Writing header text chunk %d, type %d", i,
info_ptr->text[i].compression);
/* An internationalized chunk? */
if (info_ptr->text[i].compression > 0)
{
#ifdef PNG_WRITE_iTXt_SUPPORTED
/* Write international chunk */
png_write_iTXt(png_ptr,
info_ptr->text[i].compression,
info_ptr->text[i].key,
info_ptr->text[i].lang,
info_ptr->text[i].lang_key,
info_ptr->text[i].text);
/* Mark this chunk as written */
if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
else
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
#else
png_warning(png_ptr, "Unable to write international text");
#endif
}
/* If we want a compressed text chunk */
else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)
{
#ifdef PNG_WRITE_zTXt_SUPPORTED
/* Write compressed chunk */
png_write_zTXt(png_ptr, info_ptr->text[i].key,
info_ptr->text[i].text, 0,
info_ptr->text[i].compression);
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
#else
png_warning(png_ptr, "Unable to write compressed text");
#endif
}
else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
{
#ifdef PNG_WRITE_tEXt_SUPPORTED
/* Write uncompressed chunk */
png_write_tEXt(png_ptr, info_ptr->text[i].key,
info_ptr->text[i].text,
0);
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
#else
/* Can't get here */
png_warning(png_ptr, "Unable to write uncompressed text");
#endif
}
}
#endif /* tEXt */
#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
if (info_ptr->unknown_chunks_num)
{
png_unknown_chunk *up;
png_debug(5, "writing extra chunks");
for (up = info_ptr->unknown_chunks;
up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
up++)
{
int keep = png_handle_as_unknown(png_ptr, up->name);
if (keep != PNG_HANDLE_CHUNK_NEVER &&
up->location &&
(up->location & PNG_HAVE_PLTE) &&
!(up->location & PNG_HAVE_IDAT) &&
!(up->location & PNG_AFTER_IDAT) &&
((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
(png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
{
png_write_chunk(png_ptr, up->name, up->data, up->size);
}
}
}
#endif
}
/* Writes all the PNG information. This is the suggested way to use the
* library. If you have a new chunk to add, make a function to write it,
* and put it in the correct location here. If you want the chunk written
* after the image data, put it in png_write_end(). I strongly encourage
* you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing
* the chunk, as that will keep the code from breaking if you want to just
* write a plain PNG file. If you have long comments, I suggest writing
* them in png_write_end(), and compressing them.
*/
void
png_write_info(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
int i;
#endif
png_debug(1, "in png_write_info\n");
png_write_sig(png_ptr); /* write PNG signature */
/* write IHDR information. */
png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,
info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,
info_ptr->filter_type,
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
info_ptr->interlace_type);
#else
0);
#endif
/* the rest of these check to see if the valid field has the appropriate
flag set, and if it does, writes the chunk. */
#if defined(PNG_WRITE_gAMA_SUPPORTED)
if (info_ptr->valid & PNG_INFO_gAMA)
png_write_gAMA(png_ptr, info_ptr->gamma);
#endif
#if defined(PNG_WRITE_sRGB_SUPPORTED)
if (info_ptr->valid & PNG_INFO_sRGB)
png_write_sRGB(png_ptr, (int)info_ptr->srgb_intent);
#endif
#if defined(PNG_WRITE_sBIT_SUPPORTED)
if (info_ptr->valid & PNG_INFO_sBIT)
png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);
#endif
#if defined(PNG_WRITE_cHRM_SUPPORTED)
if (info_ptr->valid & PNG_INFO_cHRM)
png_write_cHRM(png_ptr,
info_ptr->x_white, info_ptr->y_white,
info_ptr->x_red, info_ptr->y_red,
info_ptr->x_green, info_ptr->y_green,
info_ptr->x_blue, info_ptr->y_blue);
#endif
if (info_ptr->valid & PNG_INFO_PLTE)
png_write_PLTE(png_ptr, info_ptr->palette,
(png_uint_32)info_ptr->num_palette);
else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
png_error(png_ptr, "Valid palette required for paletted images\n");
#if defined(PNG_WRITE_tRNS_SUPPORTED)
if (info_ptr->valid & PNG_INFO_tRNS)
{
#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
/* invert the alpha channel (in tRNS) */
if (png_ptr->transformations & PNG_INVERT_ALPHA &&
info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
{
int j;
for (j=0; j<(int)info_ptr->num_trans; j++)
info_ptr->trans[j] = 255 - info_ptr->trans[j];
}
#endif
png_write_tRNS(png_ptr, info_ptr->trans, &(info_ptr->trans_values),
info_ptr->num_trans, info_ptr->color_type);
}
#endif
#if defined(PNG_WRITE_bKGD_SUPPORTED)
if (info_ptr->valid & PNG_INFO_bKGD)
png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
#endif
#if defined(PNG_WRITE_hIST_SUPPORTED)
if (info_ptr->valid & PNG_INFO_hIST)
png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
#endif
#if defined(PNG_WRITE_oFFs_SUPPORTED)
if (info_ptr->valid & PNG_INFO_oFFs)
png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
info_ptr->offset_unit_type);
#endif
#if defined(PNG_WRITE_pCAL_SUPPORTED)
if (info_ptr->valid & PNG_INFO_pCAL)
png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
info_ptr->pcal_units, info_ptr->pcal_params);
#endif
#if defined(PNG_WRITE_pHYs_SUPPORTED)
if (info_ptr->valid & PNG_INFO_pHYs)
png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
#endif
#if defined(PNG_WRITE_tIME_SUPPORTED)
if (info_ptr->valid & PNG_INFO_tIME)
{
png_write_tIME(png_ptr, &(info_ptr->mod_time));
png_ptr->flags |= PNG_FLAG_WROTE_tIME;
}
#endif
#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
/* Check to see if we need to write text chunks */
for (i = 0; i < info_ptr->num_text; i++)
{
png_debug2(2, "Writing header text chunk %d, type %d\n", i,
info_ptr->text[i].compression);
/* If we want a compressed text chunk */
if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)
{
#if defined(PNG_WRITE_zTXt_SUPPORTED)
/* write compressed chunk */
png_write_zTXt(png_ptr, info_ptr->text[i].key,
info_ptr->text[i].text, info_ptr->text[i].text_length,
info_ptr->text[i].compression);
#else
png_warning(png_ptr, "Unable to write compressed text\n");
#endif
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
}
else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
{
#if defined(PNG_WRITE_tEXt_SUPPORTED)
/* write uncompressed chunk */
png_write_tEXt(png_ptr, info_ptr->text[i].key,
info_ptr->text[i].text, info_ptr->text[i].text_length);
#else
png_warning(png_ptr, "Unable to write uncompressed text\n");
#endif
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
}
}
#endif
}