| /*------------------------------------- | |
| * PNGFILE.C -- Image File Functions | |
| *------------------------------------- | |
| * | |
| * Copyright 2000,2017 Willem van Schaik. | |
| * | |
| * This code is released under the libpng license. | |
| * For conditions of distribution and use, see the disclaimer | |
| * and license in png.h | |
| */ | |
| #include <windows.h> | |
| #include <commdlg.h> | |
| #include <stdio.h> | |
| #include <stdlib.h> | |
| #include <zlib.h> | |
| #include "png.h" | |
| #include "pngfile.h" | |
| #include "cexcept.h" | |
| define_exception_type(const char *); | |
| extern struct exception_context the_exception_context[1]; | |
| struct exception_context the_exception_context[1]; | |
| png_const_charp msg; | |
| static OPENFILENAME ofn; | |
| static png_structp png_ptr = NULL; | |
| static png_infop info_ptr = NULL; | |
| /* cexcept interface */ | |
| static void | |
| png_cexcept_error(png_structp png_ptr, png_const_charp msg) | |
| { | |
| if(png_ptr) | |
| ; | |
| #ifdef PNG_CONSOLE_IO_SUPPORTED | |
| fprintf(stderr, "libpng error: %s\n", msg); | |
| #endif | |
| { | |
| Throw msg; | |
| } | |
| } | |
| /* Windows open-file functions */ | |
| void PngFileInitialize (HWND hwnd) | |
| { | |
| static TCHAR szFilter[] = TEXT ("PNG Files (*.PNG)\0*.png\0") | |
| TEXT ("All Files (*.*)\0*.*\0\0"); | |
| ofn.lStructSize = sizeof (OPENFILENAME); | |
| ofn.hwndOwner = hwnd; | |
| ofn.hInstance = NULL; | |
| ofn.lpstrFilter = szFilter; | |
| ofn.lpstrCustomFilter = NULL; | |
| ofn.nMaxCustFilter = 0; | |
| ofn.nFilterIndex = 0; | |
| ofn.lpstrFile = NULL; /* Set in Open and Close functions */ | |
| ofn.nMaxFile = MAX_PATH; | |
| ofn.lpstrFileTitle = NULL; /* Set in Open and Close functions */ | |
| ofn.nMaxFileTitle = MAX_PATH; | |
| ofn.lpstrInitialDir = NULL; | |
| ofn.lpstrTitle = NULL; | |
| ofn.Flags = 0; /* Set in Open and Close functions */ | |
| ofn.nFileOffset = 0; | |
| ofn.nFileExtension = 0; | |
| ofn.lpstrDefExt = TEXT ("png"); | |
| ofn.lCustData = 0; | |
| ofn.lpfnHook = NULL; | |
| ofn.lpTemplateName = NULL; | |
| } | |
| BOOL PngFileOpenDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName) | |
| { | |
| ofn.hwndOwner = hwnd; | |
| ofn.lpstrFile = pstrFileName; | |
| ofn.lpstrFileTitle = pstrTitleName; | |
| ofn.Flags = OFN_HIDEREADONLY; | |
| return GetOpenFileName (&ofn); | |
| } | |
| BOOL PngFileSaveDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName) | |
| { | |
| ofn.hwndOwner = hwnd; | |
| ofn.lpstrFile = pstrFileName; | |
| ofn.lpstrFileTitle = pstrTitleName; | |
| ofn.Flags = OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT; | |
| return GetSaveFileName (&ofn); | |
| } | |
| /* PNG image handler functions */ | |
| BOOL PngLoadImage (PTSTR pstrFileName, png_byte **ppbImageData, | |
| int *piWidth, int *piHeight, int *piChannels, png_color *pBkgColor) | |
| { | |
| static FILE *pfFile; | |
| png_byte pbSig[8]; | |
| int iBitDepth; | |
| int iColorType; | |
| double dGamma; | |
| png_color_16 *pBackground; | |
| png_uint_32 ulChannels; | |
| png_uint_32 ulRowBytes; | |
| png_byte *pbImageData = *ppbImageData; | |
| static png_byte **ppbRowPointers = NULL; | |
| int i; | |
| /* open the PNG input file */ | |
| if (!pstrFileName) | |
| { | |
| *ppbImageData = pbImageData = NULL; | |
| return FALSE; | |
| } | |
| if (!(pfFile = fopen(pstrFileName, "rb"))) | |
| { | |
| *ppbImageData = pbImageData = NULL; | |
| return FALSE; | |
| } | |
| /* first check the eight byte PNG signature */ | |
| fread(pbSig, 1, 8, pfFile); | |
| if (png_sig_cmp(pbSig, 0, 8)) | |
| { | |
| *ppbImageData = pbImageData = NULL; | |
| return FALSE; | |
| } | |
| /* create the two png(-info) structures */ | |
| png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, | |
| (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL); | |
| if (!png_ptr) | |
| { | |
| *ppbImageData = pbImageData = NULL; | |
| return FALSE; | |
| } | |
| info_ptr = png_create_info_struct(png_ptr); | |
| if (!info_ptr) | |
| { | |
| png_destroy_read_struct(&png_ptr, NULL, NULL); | |
| *ppbImageData = pbImageData = NULL; | |
| return FALSE; | |
| } | |
| Try | |
| { | |
| /* initialize the png structure */ | |
| #ifdef PNG_STDIO_SUPPORTED | |
| png_init_io(png_ptr, pfFile); | |
| #else | |
| png_set_read_fn(png_ptr, (png_voidp)pfFile, png_read_data); | |
| #endif | |
| png_set_sig_bytes(png_ptr, 8); | |
| /* read all PNG info up to image data */ | |
| png_read_info(png_ptr, info_ptr); | |
| /* get width, height, bit-depth and color-type */ | |
| png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth, | |
| &iColorType, NULL, NULL, NULL); | |
| /* expand images of all color-type and bit-depth to 3x8-bit RGB */ | |
| /* let the library process alpha, transparency, background, etc. */ | |
| #ifdef PNG_READ_16_TO_8_SUPPORTED | |
| if (iBitDepth == 16) | |
| # ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED | |
| png_set_scale_16(png_ptr); | |
| # else | |
| png_set_strip_16(png_ptr); | |
| # endif | |
| #endif | |
| if (iColorType == PNG_COLOR_TYPE_PALETTE) | |
| png_set_expand(png_ptr); | |
| if (iBitDepth < 8) | |
| png_set_expand(png_ptr); | |
| if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) | |
| png_set_expand(png_ptr); | |
| if (iColorType == PNG_COLOR_TYPE_GRAY || | |
| iColorType == PNG_COLOR_TYPE_GRAY_ALPHA) | |
| png_set_gray_to_rgb(png_ptr); | |
| /* set the background color to draw transparent and alpha images over */ | |
| if (png_get_bKGD(png_ptr, info_ptr, &pBackground)) | |
| { | |
| png_set_background(png_ptr, pBackground, PNG_BACKGROUND_GAMMA_FILE, 1, 1.0); | |
| pBkgColor->red = (byte) pBackground->red; | |
| pBkgColor->green = (byte) pBackground->green; | |
| pBkgColor->blue = (byte) pBackground->blue; | |
| } | |
| else | |
| { | |
| pBkgColor = NULL; | |
| } | |
| /* if required set gamma conversion */ | |
| if (png_get_gAMA(png_ptr, info_ptr, &dGamma)) | |
| png_set_gamma(png_ptr, (double) 2.2, dGamma); | |
| /* after the transformations are registered, update info_ptr data */ | |
| png_read_update_info(png_ptr, info_ptr); | |
| /* get again width, height and the new bit-depth and color-type */ | |
| png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth, | |
| &iColorType, NULL, NULL, NULL); | |
| /* row_bytes is the width x number of channels */ | |
| ulRowBytes = png_get_rowbytes(png_ptr, info_ptr); | |
| ulChannels = png_get_channels(png_ptr, info_ptr); | |
| *piChannels = ulChannels; | |
| /* now we can allocate memory to store the image */ | |
| if (pbImageData) | |
| { | |
| free (pbImageData); | |
| pbImageData = NULL; | |
| } | |
| if ((*piHeight) > ((size_t)(-1))/ulRowBytes) { | |
| { | |
| png_error(png_ptr, "Visual PNG: image is too big"); | |
| } | |
| if ((pbImageData = (png_byte *) malloc(ulRowBytes * (*piHeight) | |
| * sizeof(png_byte))) == NULL) | |
| { | |
| png_error(png_ptr, "Visual PNG: out of memory"); | |
| } | |
| *ppbImageData = pbImageData; | |
| /* and allocate memory for an array of row-pointers */ | |
| if ((ppbRowPointers = (png_bytepp) malloc((*piHeight) | |
| * sizeof(png_bytep))) == NULL) | |
| { | |
| png_error(png_ptr, "Visual PNG: out of memory"); | |
| } | |
| /* set the individual row-pointers to point at the correct offsets */ | |
| for (i = 0; i < (*piHeight); i++) | |
| ppbRowPointers[i] = pbImageData + i * ulRowBytes; | |
| /* now we can go ahead and just read the whole image */ | |
| png_read_image(png_ptr, ppbRowPointers); | |
| /* read the additional chunks in the PNG file (not really needed) */ | |
| png_read_end(png_ptr, NULL); | |
| /* and we're done */ | |
| free (ppbRowPointers); | |
| ppbRowPointers = NULL; | |
| /* yepp, done */ | |
| } | |
| Catch (msg) | |
| { | |
| png_destroy_read_struct(&png_ptr, &info_ptr, NULL); | |
| *ppbImageData = pbImageData = NULL; | |
| if(ppbRowPointers) | |
| free (ppbRowPointers); | |
| fclose(pfFile); | |
| return FALSE; | |
| } | |
| fclose (pfFile); | |
| return TRUE; | |
| } | |
| BOOL PngSaveImage (PTSTR pstrFileName, png_byte *pDiData, | |
| int iWidth, int iHeight, png_color bkgColor) | |
| { | |
| const int ciBitDepth = 8; | |
| const int ciChannels = 3; | |
| static FILE *pfFile; | |
| png_uint_32 ulRowBytes; | |
| static png_byte **ppbRowPointers = NULL; | |
| int i; | |
| /* open the PNG output file */ | |
| if (!pstrFileName) | |
| return FALSE; | |
| if (!(pfFile = fopen(pstrFileName, "wb"))) | |
| return FALSE; | |
| /* prepare the standard PNG structures */ | |
| png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, | |
| (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL); | |
| if (!png_ptr) | |
| { | |
| fclose(pfFile); | |
| return FALSE; | |
| } | |
| info_ptr = png_create_info_struct(png_ptr); | |
| if (!info_ptr) { | |
| fclose(pfFile); | |
| png_destroy_write_struct(&png_ptr, (png_infopp) NULL); | |
| return FALSE; | |
| } | |
| Try | |
| { | |
| /* initialize the png structure */ | |
| #ifdef PNG_STDIO_SUPPORTED | |
| png_init_io(png_ptr, pfFile); | |
| #else | |
| png_set_write_fn(png_ptr, (png_voidp)pfFile, png_write_data, png_flush); | |
| #endif | |
| /* we're going to write a very simple 3x8-bit RGB image */ | |
| png_set_IHDR(png_ptr, info_ptr, iWidth, iHeight, ciBitDepth, | |
| PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, | |
| PNG_FILTER_TYPE_BASE); | |
| /* write the file header information */ | |
| png_write_info(png_ptr, info_ptr); | |
| /* swap the BGR pixels in the DiData structure to RGB */ | |
| png_set_bgr(png_ptr); | |
| /* row_bytes is the width x number of channels */ | |
| ulRowBytes = iWidth * ciChannels; | |
| /* we can allocate memory for an array of row-pointers */ | |
| if ((ppbRowPointers = (png_bytepp) malloc(iHeight * sizeof(png_bytep))) == NULL) | |
| Throw "Visualpng: Out of memory"; | |
| /* set the individual row-pointers to point at the correct offsets */ | |
| for (i = 0; i < iHeight; i++) | |
| ppbRowPointers[i] = pDiData + i * (((ulRowBytes + 3) >> 2) << 2); | |
| /* write out the entire image data in one call */ | |
| png_write_image (png_ptr, ppbRowPointers); | |
| /* write the additional chunks to the PNG file (not really needed) */ | |
| png_write_end(png_ptr, info_ptr); | |
| /* and we're done */ | |
| free (ppbRowPointers); | |
| ppbRowPointers = NULL; | |
| /* clean up after the write, and free any memory allocated */ | |
| png_destroy_write_struct(&png_ptr, (png_infopp) NULL); | |
| /* yepp, done */ | |
| } | |
| Catch (msg) | |
| { | |
| png_destroy_write_struct(&png_ptr, (png_infopp) NULL); | |
| if(ppbRowPointers) | |
| free (ppbRowPointers); | |
| fclose(pfFile); | |
| return FALSE; | |
| } | |
| fclose (pfFile); | |
| return TRUE; | |
| } | |
| #ifndef PNG_STDIO_SUPPORTED | |
| static void | |
| png_read_data(png_structp png_ptr, png_bytep data, size_t length) | |
| { | |
| size_t check; | |
| /* fread() returns 0 on error, so it is OK to store this in a size_t | |
| * instead of an int, which is what fread() actually returns. | |
| */ | |
| check = fread(data, 1, length, (FILE *)png_ptr->io_ptr); | |
| if (check != length) | |
| { | |
| png_error(png_ptr, "Read Error"); | |
| } | |
| } | |
| static void | |
| png_write_data(png_structp png_ptr, png_bytep data, size_t length) | |
| { | |
| png_uint_32 check; | |
| check = fwrite(data, 1, length, (FILE *)(png_ptr->io_ptr)); | |
| if (check != length) | |
| { | |
| png_error(png_ptr, "Write Error"); | |
| } | |
| } | |
| static void | |
| png_flush(png_structp png_ptr) | |
| { | |
| FILE *io_ptr; | |
| io_ptr = (FILE *)CVT_PTR((png_ptr->io_ptr)); | |
| if (io_ptr != NULL) | |
| fflush(io_ptr); | |
| } | |
| #endif | |
| /*----------------- | |
| * end of source | |
| *----------------- | |
| */ |