// fpng.h - unlicense (see end of fpng.cpp) #pragma once #include #include #include #ifndef FPNG_TRAIN_HUFFMAN_TABLES // Set to 1 when using the -t (training) option in fpng_test to generate new opaque/alpha Huffman tables for the single pass encoder. #define FPNG_TRAIN_HUFFMAN_TABLES (0) #endif namespace fpng { // ---- Library initialization - call once to identify if the processor supports SSE. // Otherwise you'll only get scalar fallbacks. void fpng_init(); // ---- Useful Utilities // Returns true if the CPU supports SSE 4.1, and SSE support wasn't disabled by setting FPNG_NO_SSE=1. // fpng_init() must have been called first, or it'll assert and return false. bool fpng_cpu_supports_sse41(); // Fast CRC-32 SSE4.1+pclmul or a scalar fallback (slice by 4) const uint32_t FPNG_CRC32_INIT = 0; uint32_t fpng_crc32(const void* pData, size_t size, uint32_t prev_crc32 = FPNG_CRC32_INIT); // Fast Adler32 SSE4.1 Adler-32 with a scalar fallback. const uint32_t FPNG_ADLER32_INIT = 1; uint32_t fpng_adler32(const void* pData, size_t size, uint32_t adler = FPNG_ADLER32_INIT); // ---- Compression enum { // Enables computing custom Huffman tables for each file, instead of using the custom global tables. // Results in roughly 6% smaller files on average, but compression is around 40% slower. FPNG_ENCODE_SLOWER = 1, // Only use raw Deflate blocks (no compression at all). Intended for testing. FPNG_FORCE_UNCOMPRESSED = 2, }; // Fast PNG encoding. The resulting file can be decoded either using a standard PNG decoder or by the fpng_decode_memory() function below. // pImage: pointer to RGB or RGBA image pixels, R first in memory, B/A last. // w/h - image dimensions. Image's row pitch in bytes must is w*num_chans. // num_chans must be 3 or 4. bool fpng_encode_image_to_memory(const void* pImage, uint32_t w, uint32_t h, uint32_t num_chans, std::vector& out_buf, uint32_t flags = 0); #ifndef FPNG_NO_STDIO // Fast PNG encoding to the specified file. bool fpng_encode_image_to_file(const char* pFilename, const void* pImage, uint32_t w, uint32_t h, uint32_t num_chans, uint32_t flags = 0); #endif // ---- Decompression enum { FPNG_DECODE_SUCCESS = 0, // file is a valid PNG file and written by FPNG and the decode succeeded FPNG_DECODE_NOT_FPNG, // file is a valid PNG file, but it wasn't written by FPNG so you should try decoding it with a general purpose PNG decoder FPNG_DECODE_INVALID_ARG, // invalid function parameter FPNG_DECODE_FAILED_NOT_PNG, // file cannot be a PNG file FPNG_DECODE_FAILED_HEADER_CRC32, // a chunk CRC32 check failed, file is likely corrupted or not PNG FPNG_DECODE_FAILED_INVALID_DIMENSIONS, // invalid image dimensions in IHDR chunk (0 or too large) FPNG_DECODE_FAILED_DIMENSIONS_TOO_LARGE, // decoding the file fully into memory would likely require too much memory (only on 32bpp builds) FPNG_DECODE_FAILED_CHUNK_PARSING, // failed while parsing the chunk headers, or file is corrupted FPNG_DECODE_FAILED_INVALID_IDAT, // IDAT data length is too small and cannot be valid, file is either corrupted or it's a bug // fpng_decode_file() specific errors FPNG_DECODE_FILE_OPEN_FAILED, FPNG_DECODE_FILE_TOO_LARGE, FPNG_DECODE_FILE_READ_FAILED, FPNG_DECODE_FILE_SEEK_FAILED }; // Fast PNG decoding of files ONLY created by fpng_encode_image_to_memory() or fpng_encode_image_to_file(). // If fpng_get_info() or fpng_decode_memory() returns FPNG_DECODE_NOT_FPNG, you should decode the PNG by falling back to a general purpose decoder. // // fpng_get_info() parses the PNG header and iterates through all chunks to determine if it's a file written by FPNG, but does not decompress the actual image data so it's relatively fast. // // pImage, image_size: Pointer to PNG image data and its size // width, height: output image's dimensions // channels_in_file: will be 3 or 4 // // Returns FPNG_DECODE_SUCCESS on success, otherwise one of the failure codes above. // If FPNG_DECODE_NOT_FPNG is returned, you must decompress the file with a general purpose PNG decoder. // If another error occurs, the file is likely corrupted or invalid, but you can still try to decompress the file with another decoder (which will likely fail). int fpng_get_info(const void* pImage, uint32_t image_size, uint32_t& width, uint32_t& height, uint32_t& channels_in_file); // fpng_decode_memory() decompresses 24/32bpp PNG files ONLY encoded by this module. // If the image was written by FPNG, it will decompress the image data, otherwise it will return FPNG_DECODE_NOT_FPNG in which case you should fall back to a general purpose PNG decoder (lodepng, stb_image, libpng, etc.) // // pImage, image_size: Pointer to PNG image data and its size // out: Output 24/32bpp image buffer // width, height: output image's dimensions // channels_in_file: will be 3 or 4 // desired_channels: must be 3 or 4 // // If the image is 24bpp and 32bpp is requested, the alpha values will be set to 0xFF. // If the image is 32bpp and 24bpp is requested, the alpha values will be discarded. // // Returns FPNG_DECODE_SUCCESS on success, otherwise one of the failure codes above. // If FPNG_DECODE_NOT_FPNG is returned, you must decompress the file with a general purpose PNG decoder. // If another error occurs, the file is likely corrupted or invalid, but you can still try to decompress the file with another decoder (which will likely fail). int fpng_decode_memory(const void* pImage, uint32_t image_size, std::vector& out, uint32_t& width, uint32_t& height, uint32_t& channels_in_file, uint32_t desired_channels); #ifndef FPNG_NO_STDIO int fpng_decode_file(const char* pFilename, std::vector& out, uint32_t& width, uint32_t& height, uint32_t& channels_in_file, uint32_t desired_channels); #endif // ---- Internal API used for Huffman table training purposes #if FPNG_TRAIN_HUFFMAN_TABLES const uint32_t HUFF_COUNTS_SIZE = 288; extern uint64_t g_huff_counts[HUFF_COUNTS_SIZE]; bool create_dynamic_block_prefix(uint64_t* pFreq, uint32_t num_chans, std::vector& prefix, uint64_t& bit_buf, int& bit_buf_size, uint32_t *pCodes, uint8_t *pCodesizes); #endif } // namespace fpng