diff options
Diffstat (limited to 'lib/gdi/epng.cpp')
| -rw-r--r-- | lib/gdi/epng.cpp | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/lib/gdi/epng.cpp b/lib/gdi/epng.cpp new file mode 100644 index 00000000..d476ec3a --- /dev/null +++ b/lib/gdi/epng.cpp @@ -0,0 +1,187 @@ +#include <png.h> +#include <stdio.h> +#include <lib/gdi/epng.h> +#include <unistd.h> + +gImage *loadPNG(const char *filename) +{ + __u8 header[8]; + FILE *fp=fopen(filename, "rb"); + + gImage *res=0; + + if (!fp) + { +// eDebug("couldn't open %s", filename ); + return 0; + } + if (!fread(header, 8, 1, fp)) + { + eDebug("couldn't read"); + fclose(fp); + return 0; + } + if (png_sig_cmp(header, 0, 8)) + { + fclose(fp); + return 0; + } + png_structp png_ptr=png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0); + if (!png_ptr) + { + eDebug("no pngptr"); + fclose(fp); + return 0; + } + png_infop info_ptr=png_create_info_struct(png_ptr); + if (!info_ptr) + { + eDebug("no info ptr"); + png_destroy_read_struct(&png_ptr, (png_infopp)0, (png_infopp)0); + fclose(fp); + return 0; + } + png_infop end_info = png_create_info_struct(png_ptr); + if (!end_info) + { + eDebug("no end"); + png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp)NULL); + fclose(fp); + return 0; + } + if (setjmp(png_ptr->jmpbuf)) + { + eDebug("das war wohl nix"); + png_destroy_read_struct(&png_ptr, &info_ptr, &end_info); + fclose(fp); + if (res) + delete res; + return 0; + } + png_init_io(png_ptr, fp); + png_set_sig_bytes(png_ptr, 8); + png_set_invert_alpha(png_ptr); + png_read_info(png_ptr, info_ptr); + + png_uint_32 width, height; + int bit_depth; + int color_type; + + png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, 0, 0, 0); + +// eDebug("%s: %dx%dx%d png, %d", filename, (int)width, (int)height, (int)bit_depth, color_type); + + if (color_type != 6) + { + res=new gImage(eSize(width, height), bit_depth); + + png_bytep *rowptr=new png_bytep[height]; + + for (unsigned int i=0; i<height; i++) + rowptr[i]=((png_byte*)(res->data))+i*res->stride; + png_read_rows(png_ptr, rowptr, 0, height); + + delete rowptr; + + if (png_get_valid(png_ptr, info_ptr, PNG_INFO_PLTE)) + { + png_color *palette; + int num_palette; + png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette); + if (num_palette) + res->clut.data=new gRGB[num_palette]; + else + res->clut.data=0; + res->clut.colors=num_palette; + + for (int i=0; i<num_palette; i++) + { + res->clut.data[i].a=0; + res->clut.data[i].r=palette[i].red; + res->clut.data[i].g=palette[i].green; + res->clut.data[i].b=palette[i].blue; + } + if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) + { + png_byte *trans; + png_get_tRNS(png_ptr, info_ptr, &trans, &num_palette, 0); + for (int i=0; i<num_palette; i++) + res->clut.data[i].a=255-trans[i]; + } + } else + { + res->clut.data=0; + res->clut.colors=0; + } + png_read_end(png_ptr, end_info); + } else + res=0; + + png_destroy_read_struct(&png_ptr, &info_ptr,&end_info); + fclose(fp); + return res; +} + +int savePNG(const char *filename, gPixmap *pixmap) +{ + FILE *fp=fopen(filename, "wb"); + if (!fp) + return -1; + png_structp png_ptr=png_create_write_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0); + if (!png_ptr) + { + eDebug("write png, couldnt allocate write struct"); + fclose(fp); + unlink(filename); + return -2; + } + png_infop info_ptr=png_create_info_struct(png_ptr); + if (!info_ptr) + { + eDebug("info"); + png_destroy_write_struct(&png_ptr, 0); + fclose(fp); + unlink(filename); + return -3; + } + if (setjmp(png_ptr->jmpbuf)) + { + eDebug("error :/"); + png_destroy_write_struct(&png_ptr, &info_ptr); + fclose(fp); + unlink(filename); + return -4; + } + png_init_io(png_ptr, fp); + png_set_filter(png_ptr, 0, PNG_FILTER_NONE|PNG_FILTER_SUB|PNG_FILTER_PAETH); + png_set_compression_level(png_ptr, Z_BEST_COMPRESSION); + + png_set_IHDR(png_ptr, info_ptr, pixmap->x, pixmap->y, pixmap->bpp, + pixmap->clut.data ? PNG_COLOR_TYPE_PALETTE : PNG_COLOR_TYPE_GRAY, + PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT); + if (pixmap->clut.data) + { + png_color palette[pixmap->clut.colors]; + png_byte trans[pixmap->clut.colors]; + for (int i=0; i<pixmap->clut.colors; ++i) + { + palette[i].red=pixmap->clut.data[i].r; + palette[i].green=pixmap->clut.data[i].g; + palette[i].blue=pixmap->clut.data[i].b; + trans[i]=255-pixmap->clut.data[i].a; + } + png_set_PLTE(png_ptr, info_ptr, palette, pixmap->clut.colors); + png_set_tRNS(png_ptr, info_ptr, trans, pixmap->clut.colors, 0); + } + png_write_info(png_ptr, info_ptr); + png_set_packing(png_ptr); + png_byte *row_pointers[pixmap->y]; + for (int i=0; i<pixmap->y; ++i) + row_pointers[i]=((png_byte*)pixmap->data)+i*pixmap->stride; + png_write_image(png_ptr, row_pointers); + png_write_end(png_ptr, info_ptr); + png_destroy_write_struct(&png_ptr, &info_ptr); + fclose(fp); + eDebug("wrote png ! fine !"); + return 0; +} |