/****************************************************************************** * * imglib.h * * SPDX-License-Identifier: MIT *****************************************************************************/ #ifndef _IMGLIB_H_ #define _IMGLIB_H_ 1 // extract bytes from an unsigned word #define LOBYTE(x) ((x)&0xff) #define HIBYTE(x) (((x) >> 8) & 0xff) // GIF encoding constants #define DESCRIPTOR_INTRODUCER 0x2c #define TERMINATOR_INTRODUCER 0x3b #define LZ_MAX_CODE 4095 // Biggest code possible in 12 bits #define LZ_BITS 12 #define FLUSH_OUTPUT 4096 // Impossible code, to signal flush #define FIRST_CODE 4097 // Impossible code, to signal first #define NO_SUCH_CODE 4098 // Impossible code, to signal empty // magfic constants and declarations for GIF LZW #define HT_SIZE 8192 /* 12bits = 4096 or twice as big! */ #define HT_KEY_MASK 0x1FFF /* 13bits keys */ #define HT_KEY_NUM_BITS 13 /* 13bits keys */ #define HT_MAX_KEY 8191 /* 13bits - 1, maximal code possible */ #define HT_MAX_CODE 4095 /* Biggest code possible in 12 bits. */ /* The 32 bits of the long are divided into two parts for the key & code: */ /* 1. The code is 12 bits as our compression algorithm is limited to 12bits */ /* 2. The key is 12 bits Prefix code + 8 bit new char or 20 bits. */ /* The key is the upper 20 bits. The code is the lower 12. */ #define HT_GET_KEY(l) (l >> 12) #define HT_GET_CODE(l) (l & 0x0FFF) #define HT_PUT_KEY(l) (l << 12) #define HT_PUT_CODE(l) (l & 0x0FFF) typedef unsigned char GifPixelType; typedef unsigned char GifByteType; typedef struct GifHashTableType { uint32_t HTable[HT_SIZE]; } GifHashTableType; typedef struct GifFilePrivateType { uint8_t BitsPerPixel; // Bits per pixel (Codes uses at least this + 1) uint16_t ClearCode; // The CLEAR LZ code uint16_t EOFCode; // The EOF LZ code uint16_t RunningCode; // The next code algorithm can generate uint16_t RunningBits; // The number of bits required to represent RunningCode uint16_t MaxCode1; // 1 bigger than max. possible code, in RunningBits bits uint16_t LastCode; // The code before the current code. uint16_t CrntCode; // Current algorithm code uint16_t CrntShiftState; // Number of bits in CrntShiftDWord uint32_t CrntShiftDWord; // For bytes decomposition into codes uint32_t PixelCount; // Number of pixels in image GifByteType Buf[256]; // Compressed input is buffered here GifHashTableType *HashTable; } GifFilePrivateType; bool createGIF(uint8_t *framebuffer, std::vector* imageBuffer, uint16_t width, uint16_t height); bool createBMP(uint8_t *framebuffer, std::vector* imageBuffer, uint16_t width, uint16_t height); bool createPBM(uint8_t *framebuffer, std::vector* gifBuffer, uint16_t width, uint16_t height); #endif /* _IMGLIB_H */