// jpgd.h - C++ class for JPEG decompression. // Public domain, Rich Geldreich <richgel99@gmail.com> #ifndef JPEG_DECODER_H #define JPEG_DECODER_H #include <stdlib.h> #include <stdio.h> #include <setjmp.h> #include <assert.h> #include <stdint.h> #ifdef _MSC_VER #define JPGD_NORETURN __declspec(noreturn) #elif defined(__GNUC__) #define JPGD_NORETURN __attribute__ ((noreturn)) #else #define JPGD_NORETURN #endif #define JPGD_HUFF_TREE_MAX_LENGTH 512 #define JPGD_HUFF_CODE_SIZE_MAX_LENGTH 256 namespace jpgd { typedef unsigned char uint8; typedef signed short int16; typedef unsigned short uint16; typedef unsigned int uint; typedef signed int int32; // Loads a JPEG image from a memory buffer or a file. // req_comps can be 1 (grayscale), 3 (RGB), or 4 (RGBA). // On return, width/height will be set to the image's dimensions, and actual_comps will be set to the either 1 (grayscale) or 3 (RGB). // Notes: For more control over where and how the source data is read, see the decompress_jpeg_image_from_stream() function below, or call the jpeg_decoder class directly. // Requesting a 8 or 32bpp image is currently a little faster than 24bpp because the jpeg_decoder class itself currently always unpacks to either 8 or 32bpp. unsigned char* decompress_jpeg_image_from_memory(const unsigned char* pSrc_data, int src_data_size, int* width, int* height, int* actual_comps, int req_comps, uint32_t flags = 0); unsigned char* decompress_jpeg_image_from_file(const char* pSrc_filename, int* width, int* height, int* actual_comps, int req_comps, uint32_t flags = 0); // Success/failure error codes. enum jpgd_status { JPGD_SUCCESS = 0, JPGD_FAILED = -1, JPGD_DONE = 1, JPGD_BAD_DHT_COUNTS = -256, JPGD_BAD_DHT_INDEX, JPGD_BAD_DHT_MARKER, JPGD_BAD_DQT_MARKER, JPGD_BAD_DQT_TABLE, JPGD_BAD_PRECISION, JPGD_BAD_HEIGHT, JPGD_BAD_WIDTH, JPGD_TOO_MANY_COMPONENTS, JPGD_BAD_SOF_LENGTH, JPGD_BAD_VARIABLE_MARKER, JPGD_BAD_DRI_LENGTH, JPGD_BAD_SOS_LENGTH, JPGD_BAD_SOS_COMP_ID, JPGD_W_EXTRA_BYTES_BEFORE_MARKER, JPGD_NO_ARITHMITIC_SUPPORT, JPGD_UNEXPECTED_MARKER, JPGD_NOT_JPEG, JPGD_UNSUPPORTED_MARKER, JPGD_BAD_DQT_LENGTH, JPGD_TOO_MANY_BLOCKS, JPGD_UNDEFINED_QUANT_TABLE, JPGD_UNDEFINED_HUFF_TABLE, JPGD_NOT_SINGLE_SCAN, JPGD_UNSUPPORTED_COLORSPACE, JPGD_UNSUPPORTED_SAMP_FACTORS, JPGD_DECODE_ERROR, JPGD_BAD_RESTART_MARKER, JPGD_BAD_SOS_SPECTRAL, JPGD_BAD_SOS_SUCCESSIVE, JPGD_STREAM_READ, JPGD_NOTENOUGHMEM, JPGD_TOO_MANY_SCANS }; // Input stream interface. // Derive from this class to read input data from sources other than files or memory. Set m_eof_flag to true when no more data is available. // The decoder is rather greedy: it will keep on calling this method until its internal input buffer is full, or until the EOF flag is set. // It the input stream contains data after the JPEG stream's EOI (end of image) marker it will probably be pulled into the internal buffer. // Call the get_total_bytes_read() method to determine the actual size of the JPEG stream after successful decoding. class jpeg_decoder_stream { public: jpeg_decoder_stream() { } virtual ~jpeg_decoder_stream() { } // The read() method is called when the internal input buffer is empty. // Parameters: // pBuf - input buffer // max_bytes_to_read - maximum bytes that can be written to pBuf // pEOF_flag - set this to true if at end of stream (no more bytes remaining) // Returns -1 on error, otherwise return the number of bytes actually written to the buffer (which may be 0). // Notes: This method will be called in a loop until you set *pEOF_flag to true or the internal buffer is full. virtual int read(uint8* pBuf, int max_bytes_to_read, bool* pEOF_flag) = 0; }; // stdio FILE stream class. class jpeg_decoder_file_stream : public jpeg_decoder_stream { jpeg_decoder_file_stream(const jpeg_decoder_file_stream&); jpeg_decoder_file_stream& operator =(const jpeg_decoder_file_stream&); FILE* m_pFile; bool m_eof_flag, m_error_flag; public: jpeg_decoder_file_stream(); virtual ~jpeg_decoder_file_stream(); bool open(const char* Pfilename); void close(); virtual int read(uint8* pBuf, int max_bytes_to_read, bool* pEOF_flag); }; // Memory stream class. class jpeg_decoder_mem_stream : public jpeg_decoder_stream { const uint8* m_pSrc_data; uint m_ofs, m_size; public: jpeg_decoder_mem_stream() : m_pSrc_data(NULL), m_ofs(0), m_size(0) { } jpeg_decoder_mem_stream(const uint8* pSrc_data, uint size) : m_pSrc_data(pSrc_data), m_ofs(0), m_size(size) { } virtual ~jpeg_decoder_mem_stream() { } bool open(const uint8* pSrc_data, uint size); void close() { m_pSrc_data = NULL; m_ofs = 0; m_size = 0; } virtual int read(uint8* pBuf, int max_bytes_to_read, bool* pEOF_flag); }; // Loads JPEG file from a jpeg_decoder_stream. unsigned char* decompress_jpeg_image_from_stream(jpeg_decoder_stream* pStream, int* width, int* height, int* actual_comps, int req_comps, uint32_t flags = 0); enum { JPGD_IN_BUF_SIZE = 8192, JPGD_MAX_BLOCKS_PER_MCU = 10, JPGD_MAX_HUFF_TABLES = 8, JPGD_MAX_QUANT_TABLES = 4, JPGD_MAX_COMPONENTS = 4, JPGD_MAX_COMPS_IN_SCAN = 4, JPGD_MAX_BLOCKS_PER_ROW = 16384, JPGD_MAX_HEIGHT = 32768, JPGD_MAX_WIDTH = 32768 }; typedef int16 jpgd_quant_t; typedef int16 jpgd_block_t; class jpeg_decoder { public: enum { cFlagLinearChromaFiltering = 1 }; // Call get_error_code() after constructing to determine if the stream is valid or not. You may call the get_width(), get_height(), etc. // methods after the constructor is called. You may then either destruct the object, or begin decoding the image by calling begin_decoding(), then decode() on each scanline. jpeg_decoder(jpeg_decoder_stream* pStream, uint32_t flags = cFlagLinearChromaFiltering); ~jpeg_decoder(); // Call this method after constructing the object to begin decompression. // If JPGD_SUCCESS is returned you may then call decode() on each scanline. int begin_decoding(); // Returns the next scan line. // For grayscale images, pScan_line will point to a buffer containing 8-bit pixels (get_bytes_per_pixel() will return 1). // Otherwise, it will always point to a buffer containing 32-bit RGBA pixels (A will always be 255, and get_bytes_per_pixel() will return 4). // Returns JPGD_SUCCESS if a scan line has been returned. // Returns JPGD_DONE if all scan lines have been returned. // Returns JPGD_FAILED if an error occurred. Call get_error_code() for a more info. int decode(const void** pScan_line, uint* pScan_line_len); inline jpgd_status get_error_code() const { return m_error_code; } inline int get_width() const { return m_image_x_size; } inline int get_height() const { return m_image_y_size; } inline int get_num_components() const { return m_comps_in_frame; } inline int get_bytes_per_pixel() const { return m_dest_bytes_per_pixel; } inline int get_bytes_per_scan_line() const { return m_image_x_size * get_bytes_per_pixel(); } // Returns the total number of bytes actually consumed by the decoder (which should equal the actual size of the JPEG file). inline int get_total_bytes_read() const { return m_total_bytes_read; } private: jpeg_decoder(const jpeg_decoder&); jpeg_decoder& operator =(const jpeg_decoder&); typedef void (*pDecode_block_func)(jpeg_decoder*, int, int, int); struct huff_tables { bool ac_table; uint look_up[256]; uint look_up2[256]; uint8 code_size[JPGD_HUFF_CODE_SIZE_MAX_LENGTH]; uint tree[JPGD_HUFF_TREE_MAX_LENGTH]; }; struct coeff_buf { uint8* pData; int block_num_x, block_num_y; int block_len_x, block_len_y; int block_size; }; struct mem_block { mem_block* m_pNext; size_t m_used_count; size_t m_size; char m_data[1]; }; jmp_buf m_jmp_state; uint32_t m_flags; mem_block* m_pMem_blocks; int m_image_x_size; int m_image_y_size; jpeg_decoder_stream* m_pStream; int m_progressive_flag; uint8 m_huff_ac[JPGD_MAX_HUFF_TABLES]; uint8* m_huff_num[JPGD_MAX_HUFF_TABLES]; // pointer to number of Huffman codes per bit size uint8* m_huff_val[JPGD_MAX_HUFF_TABLES]; // pointer to Huffman codes per bit size jpgd_quant_t* m_quant[JPGD_MAX_QUANT_TABLES]; // pointer to quantization tables int m_scan_type; // Gray, Yh1v1, Yh1v2, Yh2v1, Yh2v2 (CMYK111, CMYK4114 no longer supported) int m_comps_in_frame; // # of components in frame int m_comp_h_samp[JPGD_MAX_COMPONENTS]; // component's horizontal sampling factor int m_comp_v_samp[JPGD_MAX_COMPONENTS]; // component's vertical sampling factor int m_comp_quant[JPGD_MAX_COMPONENTS]; // component's quantization table selector int m_comp_ident[JPGD_MAX_COMPONENTS]; // component's ID int m_comp_h_blocks[JPGD_MAX_COMPONENTS]; int m_comp_v_blocks[JPGD_MAX_COMPONENTS]; int m_comps_in_scan; // # of components in scan int m_comp_list[JPGD_MAX_COMPS_IN_SCAN]; // components in this scan int m_comp_dc_tab[JPGD_MAX_COMPONENTS]; // component's DC Huffman coding table selector int m_comp_ac_tab[JPGD_MAX_COMPONENTS]; // component's AC Huffman coding table selector int m_spectral_start; // spectral selection start int m_spectral_end; // spectral selection end int m_successive_low; // successive approximation low int m_successive_high; // successive approximation high int m_max_mcu_x_size; // MCU's max. X size in pixels int m_max_mcu_y_size; // MCU's max. Y size in pixels int m_blocks_per_mcu; int m_max_blocks_per_row; int m_mcus_per_row, m_mcus_per_col; int m_mcu_org[JPGD_MAX_BLOCKS_PER_MCU]; int m_total_lines_left; // total # lines left in image int m_mcu_lines_left; // total # lines left in this MCU int m_num_buffered_scanlines; int m_real_dest_bytes_per_scan_line; int m_dest_bytes_per_scan_line; // rounded up int m_dest_bytes_per_pixel; // 4 (RGB) or 1 (Y) huff_tables* m_pHuff_tabs[JPGD_MAX_HUFF_TABLES]; coeff_buf* m_dc_coeffs[JPGD_MAX_COMPONENTS]; coeff_buf* m_ac_coeffs[JPGD_MAX_COMPONENTS]; int m_eob_run; int m_block_y_mcu[JPGD_MAX_COMPONENTS]; uint8* m_pIn_buf_ofs; int m_in_buf_left; int m_tem_flag; uint8 m_in_buf_pad_start[64]; uint8 m_in_buf[JPGD_IN_BUF_SIZE + 128]; uint8 m_in_buf_pad_end[64]; int m_bits_left; uint m_bit_buf; int m_restart_interval; int m_restarts_left; int m_next_restart_num; int m_max_mcus_per_row; int m_max_blocks_per_mcu; int m_max_mcus_per_col; uint m_last_dc_val[JPGD_MAX_COMPONENTS]; jpgd_block_t* m_pMCU_coefficients; int m_mcu_block_max_zag[JPGD_MAX_BLOCKS_PER_MCU]; uint8* m_pSample_buf; uint8* m_pSample_buf_prev; int m_crr[256]; int m_cbb[256]; int m_crg[256]; int m_cbg[256]; uint8* m_pScan_line_0; uint8* m_pScan_line_1; jpgd_status m_error_code; int m_total_bytes_read; bool m_ready_flag; bool m_eof_flag; bool m_sample_buf_prev_valid; inline int check_sample_buf_ofs(int ofs) const { assert(ofs >= 0); assert(ofs < m_max_blocks_per_row * 64); return ofs; } void free_all_blocks(); JPGD_NORETURN void stop_decoding(jpgd_status status); void* alloc(size_t n, bool zero = false); void word_clear(void* p, uint16 c, uint n); void prep_in_buffer(); void read_dht_marker(); void read_dqt_marker(); void read_sof_marker(); void skip_variable_marker(); void read_dri_marker(); void read_sos_marker(); int next_marker(); int process_markers(); void locate_soi_marker(); void locate_sof_marker(); int locate_sos_marker(); void init(jpeg_decoder_stream* pStream, uint32_t flags); void create_look_ups(); void fix_in_buffer(); void transform_mcu(int mcu_row); coeff_buf* coeff_buf_open(int block_num_x, int block_num_y, int block_len_x, int block_len_y); inline jpgd_block_t* coeff_buf_getp(coeff_buf* cb, int block_x, int block_y); void load_next_row(); void decode_next_row(); void make_huff_table(int index, huff_tables* pH); void check_quant_tables(); void check_huff_tables(); bool calc_mcu_block_order(); int init_scan(); void init_frame(); void process_restart(); void decode_scan(pDecode_block_func decode_block_func); void init_progressive(); void init_sequential(); void decode_start(); void decode_init(jpeg_decoder_stream* pStream, uint32_t flags); void H2V2Convert(); uint32_t H2V2ConvertFiltered(); void H2V1Convert(); void H2V1ConvertFiltered(); void H1V2Convert(); void H1V2ConvertFiltered(); void H1V1Convert(); void gray_convert(); void find_eoi(); inline uint get_char(); inline uint get_char(bool* pPadding_flag); inline void stuff_char(uint8 q); inline uint8 get_octet(); inline uint get_bits(int num_bits); inline uint get_bits_no_markers(int numbits); inline int huff_decode(huff_tables* pH); inline int huff_decode(huff_tables* pH, int& extrabits); // Clamps a value between 0-255. static inline uint8 clamp(int i) { if (static_cast<uint>(i) > 255) i = (((~i) >> 31) & 0xFF); return static_cast<uint8>(i); } int decode_next_mcu_row(); static void decode_block_dc_first(jpeg_decoder* pD, int component_id, int block_x, int block_y); static void decode_block_dc_refine(jpeg_decoder* pD, int component_id, int block_x, int block_y); static void decode_block_ac_first(jpeg_decoder* pD, int component_id, int block_x, int block_y); static void decode_block_ac_refine(jpeg_decoder* pD, int component_id, int block_x, int block_y); }; } // namespace jpgd #endif // JPEG_DECODER_H