/* pnginfo.h - header file for PNG reference library * * Copyright (c) 2018 Cosmin Truta * Copyright (c) 1998-2002,2004,2006-2013,2018 Glenn Randers-Pehrson * Copyright (c) 1996-1997 Andreas Dilger * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. * * This code is released under the libpng license. * For conditions of distribution and use, see the disclaimer * and license in png.h */ /* png_info is a structure that holds the information in a PNG file so * that the application can find out the characteristics of the image. * If you are reading the file, this structure will tell you what is * in the PNG file. If you are writing the file, fill in the information * you want to put into the PNG file, using png_set_*() functions, then * call png_write_info(). * * The names chosen should be very close to the PNG specification, so * consult that document for information about the meaning of each field. * * With libpng < 0.95, it was only possible to directly set and read the * the values in the png_info_struct, which meant that the contents and * order of the values had to remain fixed. With libpng 0.95 and later, * however, there are now functions that abstract the contents of * png_info_struct from the application, so this makes it easier to use * libpng with dynamic libraries, and even makes it possible to use * libraries that don't have all of the libpng ancillary chunk-handing * functionality. In libpng-1.5.0 this was moved into a separate private * file that is not visible to applications. * * The following members may have allocated storage attached that should be * cleaned up before the structure is discarded: palette, trans, text, * pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile, * splt_palettes, scal_unit, row_pointers, and unknowns. By default, these * are automatically freed when the info structure is deallocated, if they were * allocated internally by libpng. This behavior can be changed by means * of the png_data_freer() function. * * More allocation details: all the chunk-reading functions that * change these members go through the corresponding png_set_* * functions. A function to clear these members is available: see * png_free_data(). The png_set_* functions do not depend on being * able to point info structure members to any of the storage they are * passed (they make their own copies), EXCEPT that the png_set_text * functions use the same storage passed to them in the text_ptr or * itxt_ptr structure argument, and the png_set_rows and png_set_unknowns * functions do not make their own copies. */ #ifndef PNGINFO_H #define PNGINFO_H struct png_info_def { … }; #endif /* PNGINFO_H */