diff options
-rw-r--r-- | include/llmr/util/image.hpp | 14 | ||||
-rw-r--r-- | src/util/image.cpp | 50 |
2 files changed, 64 insertions, 0 deletions
diff --git a/include/llmr/util/image.hpp b/include/llmr/util/image.hpp new file mode 100644 index 0000000000..5642de986b --- /dev/null +++ b/include/llmr/util/image.hpp @@ -0,0 +1,14 @@ +#ifndef LLMR_UTIL_IMAGE +#define LLMR_UTIL_IMAGE + +#include <string> + +namespace llmr { +namespace util { + +std::string compress_png(int width, int height, void *rgba); + +} +} + +#endif diff --git a/src/util/image.cpp b/src/util/image.cpp new file mode 100644 index 0000000000..e7cb22697e --- /dev/null +++ b/src/util/image.cpp @@ -0,0 +1,50 @@ +#include <llmr/util/image.hpp> +#include <png.h> + + +std::string llmr::util::compress_png(int width, int height, void *rgba) { + png_voidp error_ptr = 0; + png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, error_ptr, NULL, NULL); + if (!png_ptr) { + fprintf(stderr, "Couldn't create png_ptr\n"); + return ""; + } + + png_infop info_ptr = png_create_info_struct(png_ptr); + if (!png_ptr) { + png_destroy_write_struct(&png_ptr, (png_infopp)0); + fprintf(stderr, "Couldn't create info_ptr\n"); + return ""; + } + + png_set_IHDR(png_ptr, info_ptr, width, height, 8, PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE, + PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT); + + jmp_buf *jmp_context = (jmp_buf *)png_get_error_ptr(png_ptr); + if (jmp_context) { + png_destroy_write_struct(&png_ptr, &info_ptr); + return ""; + } + + std::string result; + png_set_write_fn(png_ptr, &result, [](png_structp png_ptr, png_bytep data, png_size_t length) { + std::string *out = static_cast<std::string *>(png_get_io_ptr(png_ptr)); + out->append(reinterpret_cast<char *>(data), length); + }, NULL); + + struct ptrs { + ptrs(size_t count) : rows(new png_bytep[count]) {} + ~ptrs() { delete[] rows; } + png_bytep *rows = nullptr; + } pointers(height); + + for (int i = 0; i < height; i++) { + pointers.rows[i] = (png_bytep)((png_bytep)rgba + width * 4 * i); + } + + png_set_rows(png_ptr, info_ptr, pointers.rows); + png_write_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, NULL); + png_destroy_write_struct(&png_ptr, &info_ptr); + + return result; +} |