/* 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 PNGAPI
png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr)
{
png_debug(1, "in png_write_info_before_PLTE\n");
if (png_ptr == NULL || info_ptr == NULL)
return;
if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
{
png_write_sig(png_ptr); /* write PNG signature */
#if defined(PNG_MNG_FEATURES_SUPPORTED)
if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&(png_ptr->mng_features_permitted))
{
png_warning(png_ptr,"MNG features are not allowed in a PNG datastream");
png_ptr->mng_features_permitted=0;
}
#endif
/* 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)
{
# ifdef PNG_FLOATING_POINT_SUPPORTED
png_write_gAMA(png_ptr, info_ptr->gamma);
#else
#ifdef PNG_FIXED_POINT_SUPPORTED
png_write_gAMA_fixed(png_ptr, info_ptr->int_gamma);
# endif
#endif
}
#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_iCCP_SUPPORTED)
if (info_ptr->valid & PNG_INFO_iCCP)
png_write_iCCP(png_ptr, info_ptr->iccp_name, PNG_COMPRESSION_TYPE_BASE,
info_ptr->iccp_profile, (int)info_ptr->iccp_proflen);
#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)
{
#ifdef PNG_FLOATING_POINT_SUPPORTED
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);
#else
# ifdef PNG_FIXED_POINT_SUPPORTED
png_write_cHRM_fixed(png_ptr,
info_ptr->int_x_white, info_ptr->int_y_white,
info_ptr->int_x_red, info_ptr->int_y_red,
info_ptr->int_x_green, info_ptr->int_y_green,
info_ptr->int_x_blue, info_ptr->int_y_blue);
# endif
#endif
}
#endif
#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
if (info_ptr->unknown_chunks_num)
{
png_unknown_chunk *up;
png_debug(5, "writing extra chunks\n");
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->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
png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;
}
/* 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
}
/*
* Copies a PNG file stream to another PNG file stream.
*/
int opng_copy_png(struct opng_codec_context *context, FILE *in_stream, const char *Infile, FILE *out_stream, const char *Outfile)
{
volatile png_bytep buf; /* volatile is required by cexcept */
const png_uint_32 buf_size_incr = 4096;
png_uint_32 length;
png_byte chunk_hdr[8];
const char * volatile err_msg;
int volatile result = 0;
context->libpng_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, 0, opng_write_error, opng_write_warning);
if (!context->libpng_ptr)
{
opng_error(0, "Out of memory");
exit(1);
}
struct opng_encoding_stats * stats = context->stats;
opng_init_stats(stats);
context->stream = out_stream;
context->fname = Outfile;
png_set_write_fn(context->libpng_ptr, context, opng_write_data, 0);
Try
{
buf = 0;
png_uint_32 buf_size = 0;
/* Write the signature in the output file. */
png_write_sig(context->libpng_ptr);
/* Copy all chunks until IEND. */
/* Error checking is done only at a very basic level. */
do
{
if (fread(chunk_hdr, 8, 1, in_stream) != 1) /* length + name */
{
opng_error(Infile, "Read error");
result = -1;
break;
}
length = png_get_uint_32(chunk_hdr);
if (length > PNG_UINT_31_MAX)
{
if (!buf && length == 0x89504e47UL) /* "\x89PNG" */
continue; /* skip the signature */
opng_error(Infile, "Data error");
result = -1;
break;
}
if (length + 4 > buf_size)
{
png_free(context->libpng_ptr, buf);
buf_size = (((length + 4) + (buf_size_incr - 1))
/ buf_size_incr) * buf_size_incr;
buf = (png_bytep)png_malloc(context->libpng_ptr, buf_size);
if (!buf) {
exit(1);
}
/* Do not use realloc() here, it's unnecessarily slow. */
}
if (fread(buf, length + 4, 1, in_stream) != 1) /* data + crc */
{
opng_error(Infile, "Read error");
result = -1;
break;
}
png_write_chunk(context->libpng_ptr, chunk_hdr + 4, buf, length);
} while (memcmp(chunk_hdr + 4, opng_sig_IEND, 4) != 0);
}
Catch (err_msg)
{
opng_error(Outfile, err_msg);
result = -1;
}
png_free(context->libpng_ptr, buf);
png_destroy_write_struct(&context->libpng_ptr, 0);
return result;
}
static uint8_t png_write( png_structp writePtr, png_image * image, uint32_t flags )
{
const uint32_t h = image->height;
const uint32_t w = image->width;
const uint8_t * p = image->data;
const uint32_t bitDepth = 8;
const uint32_t channels = 4;
png_infop infoPtr = png_create_info_struct( writePtr );
if (!infoPtr)
{
pngio_error( "Couldn't initialize PNG info struct" );
png_destroy_write_struct( & writePtr, NULL );
return 0;
}
if (setjmp( png_jmpbuf( writePtr ) ))
{
png_destroy_write_struct( & writePtr, & infoPtr );
pngio_error( "An error occured while writing the PNG file." );
return 0;
}
png_set_filter( writePtr, 0, PNG_FILTER_NONE );
#ifdef PNG_APPLE_MODE_SUPPORTED
if (png_get_apple_mode())
{
png_write_sig( writePtr );
png_set_sig_bytes( writePtr, 8 );
png_set_compression_window_bits( writePtr, -15 );
png_set_write_user_transform_fn( writePtr, png_write_swap_and_premultiply_transform );
png_set_user_transform_info( writePtr, NULL, bitDepth, channels );
}
#endif
png_set_IHDR( writePtr, infoPtr, w, h, bitDepth, PNG_COLOR_TYPE_RGBA, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT );
png_set_gAMA( writePtr, infoPtr, 0.45455 );
png_set_cHRM( writePtr, infoPtr, 0.312700, 0.329, 0.64, 0.33, 0.3, 0.6, 0.15, 0.06 );
png_set_sRGB( writePtr, infoPtr, 0);
#ifdef PNG_APPLE_MODE_SUPPORTED
if (png_get_apple_mode())
{
png_byte cname[] = { 'C', 'g', 'B', 'I', '\0' };
png_byte cdata[] = { 0x50, 0x00, 0x20, 0x02 };
png_write_chunk( writePtr, cname, cdata, 4 );
}
#endif
png_write_info( writePtr, infoPtr );
const size_t bytesPerRow = w * 4;
if (flags & PNG_IMAGE_FLIP_VERTICAL)
{
for (size_t i = 0; i < h; i++)
{
png_write_row( writePtr, p + (bytesPerRow * (h - i - 1)) );
}
}
else
{
for (size_t i = 0; i < h; i++)
{
png_write_row( writePtr, p + (bytesPerRow * i) );
}
}
png_write_end( writePtr, infoPtr );
png_destroy_write_struct( & writePtr, & infoPtr );
return 1;
}
