/* * jpegdata.h * * Copyright (C) 1991, Thomas G. Lane. * This file is part of the Independent JPEG Group's software. * For conditions of distribution and use, see the accompanying README file. * * This file defines shared data structures for the various JPEG modules. */ /* * You might need to change some of the following declarations if you are * using the JPEG software within a surrounding application program * or porting it to an unusual system. */ /* If the source or destination of image data is not to be stdio streams, * these types may need work. You can replace them with some kind of * pointer or indicator that is useful to you, or just ignore 'em. * Note that the user interface and the various jrdxxx/jwrxxx modules * will also need work for non-stdio input/output. */ typedef FILE * JFILEREF; /* source or dest of JPEG-compressed data */ typedef FILE * IFILEREF; /* source or dest of non-JPEG image data */ /* These defines are used in all function definitions and extern declarations. * You could modify them if you need to change function linkage conventions, * as is shown below for use with C++. Another application would be to make * all functions global for use with code profilers that require it. * NOTE: the C++ test does the right thing if you are reading this include * file in a C++ application to link to JPEG code that's been compiled with a * regular C compiler. I'm not sure it works if you try to compile the JPEG * code with C++. */ #define METHODDEF static /* a function called through method pointers */ #define LOCAL static /* a function used only in its module */ #define GLOBAL /* a function referenced thru EXTERNs */ #ifdef __cplusplus #define EXTERN extern "C" /* a reference to a GLOBAL function */ #else #define EXTERN extern /* a reference to a GLOBAL function */ #endif /* Here is the pseudo-keyword for declaring pointers that must be "far" * on 80x86 machines. Most of the specialized coding for 80x86 is handled * by just saying "FAR *" where such a pointer is needed. In a few places * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol. */ #ifdef NEED_FAR_POINTERS #define FAR far #else #define FAR #endif /* The remaining declarations are not system-dependent, we hope. */ /* * NOTE: if you have an ancient, strict-K&R C compiler, it may choke on the * similarly-named fields in compress_info_struct and decompress_info_struct. * If this happens, you can get around it by rearranging the two structs so * that the similarly-named fields appear first and in the same order in * each struct. Since such compilers are now pretty rare, we haven't done * this in the portable code, preferring to maintain a logical ordering. */ /* This macro is used to declare a "method", that is, a function pointer. */ /* We want to supply prototype parameters if the compiler can cope. */ /* Note that the arglist parameter must be parenthesized! */ #ifdef PROTO #define METHOD(type,methodname,arglist) type (*methodname) arglist #else #define METHOD(type,methodname,arglist) type (*methodname) () #endif /* Forward references to lists of method pointers */ typedef struct external_methods_struct * external_methods_ptr; typedef struct compress_methods_struct * compress_methods_ptr; typedef struct decompress_methods_struct * decompress_methods_ptr; /* Data structures for images containing either samples or coefficients. */ /* Note that the topmost (leftmost) index is always color component. */ /* On 80x86 machines, the image arrays are too big for near pointers, */ /* but the pointer arrays can fit in near memory. */ typedef JSAMPLE FAR *JSAMPROW; /* ptr to one image row of pixel samples. */ typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */ typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */ #define DCTSIZE 8 /* The basic DCT block is 8x8 samples */ #define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */ typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */ typedef JBLOCK FAR *JBLOCKROW; /* pointer to one row of coefficient blocks */ typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */ typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */ typedef JCOEF FAR *JCOEFPTR; /* useful in a couple of places */ /* The input and output data of the DCT transform subroutines are of * the following type, which need not be the same as JCOEF. * For example, on a machine with fast floating point, it might make sense * to recode the DCT routines to use floating point; then DCTELEM would be * 'float' or 'double'. */ typedef JCOEF DCTELEM; typedef DCTELEM DCTBLOCK[DCTSIZE2]; /* Types for JPEG compression parameters and working tables. */ typedef enum { /* defines known color spaces */ CS_UNKNOWN, /* error/unspecified */ CS_GRAYSCALE, /* monochrome (only 1 component) */ CS_RGB, /* red/green/blue */ CS_YCbCr, /* Y/Cb/Cr (also known as YUV) */ CS_YIQ, /* Y/I/Q */ CS_CMYK /* C/M/Y/K */ } COLOR_SPACE; typedef struct { /* Basic info about one component */ /* These values are fixed over the whole image */ /* For compression, they must be supplied by the user interface; */ /* for decompression, they are read from the SOF marker. */ short component_id; /* identifier for this component (0..255) */ short component_index; /* its index in SOF or cinfo->comp_info[] */ short h_samp_factor; /* horizontal sampling factor (1..4) */ short v_samp_factor; /* vertical sampling factor (1..4) */ short quant_tbl_no; /* quantization table selector (0..3) */ /* These values may vary between scans */ /* For compression, they must be supplied by the user interface; */ /* for decompression, they are read from the SOS marker. */ short dc_tbl_no; /* DC entropy table selector (0..3) */ short ac_tbl_no; /* AC entropy table selector (0..3) */ /* These values are computed during compression or decompression startup */ long true_comp_width; /* component's image width in samples */ long true_comp_height; /* component's image height in samples */ /* the above are the logical dimensions of the subsampled image */ /* These values are computed before starting a scan of the component */ short MCU_width; /* number of blocks per MCU, horizontally */ short MCU_height; /* number of blocks per MCU, vertically */ short MCU_blocks; /* MCU_width * MCU_height */ long subsampled_width; /* image width in samples, after expansion */ long subsampled_height; /* image height in samples, after expansion */ /* the above are the true_comp_xxx values rounded up to multiples of */ /* the MCU dimensions; these are the working dimensions of the array */ /* as it is passed through the DCT or IDCT step. NOTE: these values */ /* differ depending on whether the component is interleaved or not!! */ } jpeg_component_info; /* DCT coefficient quantization tables. * For 8-bit precision, 'INT16' should be good enough for quantization values; * for more precision, we go for the full 16 bits. 'INT16' provides a useful * speedup on many machines (multiplication & division of JCOEFs by * quantization values is a significant chunk of the runtime). * Note: the values in a QUANT_TBL are always given in zigzag order. */ #ifdef EIGHT_BIT_SAMPLES typedef INT16 QUANT_VAL; /* element of a quantization table */ #else typedef UINT16 QUANT_VAL; /* element of a quantization table */ #endif typedef QUANT_VAL QUANT_TBL[DCTSIZE2]; /* A quantization table */ typedef QUANT_VAL * QUANT_TBL_PTR; /* pointer to same */ typedef struct { /* A Huffman coding table */ /* These two fields directly represent the contents of a JPEG DHT marker */ UINT8 bits[17]; /* bits[k] = # of symbols with codes of */ /* length k bits; bits[0] is unused */ UINT8 huffval[256]; /* The symbols, in order of incr code length */ /* This field is used only during compression. It's initialized FALSE when * the table is created, and set TRUE when it's been output to the file. */ boolean sent_table; /* TRUE when table has been output */ /* The remaining fields are computed from the above to allow more efficient * coding and decoding. These fields should be considered private to the * Huffman compression & decompression modules. */ UINT16 ehufco[256]; /* code for each symbol */ char ehufsi[256]; /* length of code for each symbol */ UINT16 mincode[17]; /* smallest code of length k */ INT32 maxcode[17]; /* largest code of length k (-1 if none) */ short valptr[17]; /* huffval[] index of 1st symbol of length k */ } HUFF_TBL; #define NUM_QUANT_TBLS 4 /* quantization tables are numbered 0..3 */ #define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */ #define NUM_ARITH_TBLS 16 /* arith-coding tables are numbered 0..15 */ #define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */ #define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */ #define MAX_BLOCKS_IN_MCU 10 /* JPEG limit on # of blocks in an MCU */ /* Working data for compression */ struct compress_info_struct { /* * All of these fields shall be established by the user interface before * calling jpeg_compress, or by the input_init or c_ui_method_selection * methods. * Most parameters can be set to reasonable defaults by j_default_compression. * Note that the UI must supply the storage for the main methods struct, * though it sets only a few of the methods there. */ compress_methods_ptr methods; /* Points to list of methods to use */ external_methods_ptr emethods; /* Points to list of methods to use */ IFILEREF input_file; /* tells input routines where to read image */ JFILEREF output_file; /* tells output routines where to write JPEG */ long image_width; /* input image width */ long image_height; /* input image height */ short input_components; /* # of color components in input image */ short data_precision; /* bits of precision in image data */ COLOR_SPACE in_color_space; /* colorspace of input file */ COLOR_SPACE jpeg_color_space; /* colorspace of JPEG file */ double input_gamma; /* image gamma of input file */ boolean write_JFIF_header; /* should a JFIF marker be written? */ /* These three values are not used by the JPEG code, only copied */ /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */ /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */ /* ratio is defined by X_density/Y_density even when density_unit=0. */ UINT8 density_unit; /* JFIF code for pixel size units */ UINT16 X_density; /* Horizontal pixel density */ UINT16 Y_density; /* Vertical pixel density */ short num_components; /* # of color components in JPEG image */ jpeg_component_info * comp_info; /* comp_info[i] describes component that appears i'th in SOF */ QUANT_TBL_PTR quant_tbl_ptrs[NUM_QUANT_TBLS]; /* ptrs to coefficient quantization tables, or NULL if not defined */ HUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; HUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; /* ptrs to Huffman coding tables, or NULL if not defined */ UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arithmetic-coding tables */ UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arithmetic-coding tables */ UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arithmetic-coding tables */ boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ boolean interleave; /* TRUE=interleaved output, FALSE=not */ boolean optimize_coding; /* TRUE=optimize entropy encoding parms */ boolean CCIR601_sampling; /* TRUE=first samples are cosited */ UINT16 restart_interval;/* MDUs per restart interval, or 0 for no restart */ /* * These fields are computed during jpeg_compress startup */ short max_h_samp_factor; /* largest h_samp_factor */ short max_v_samp_factor; /* largest v_samp_factor */ /* * These fields are valid during any one scan */ short comps_in_scan; /* # of JPEG components output this time */ jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; /* *cur_comp_info[i] describes component that appears i'th in SOS */ long MCUs_per_row; /* # of MCUs across the image */ long MCU_rows_in_scan; /* # of MCU rows in the image */ short blocks_in_MCU; /* # of DCT blocks per MCU */ short MCU_membership[MAX_BLOCKS_IN_MCU]; /* MCU_membership[i] is index in cur_comp_info of component owning */ /* i'th block in an MCU */ /* these fields are private data for the entropy encoder */ JCOEF last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each comp */ JCOEF last_dc_diff[MAX_COMPS_IN_SCAN]; /* last DC diff for each comp */ UINT16 restarts_to_go; /* MDUs left in this restart interval */ short next_restart_num; /* # of next RSTn marker (0..7) */ }; typedef struct compress_info_struct * compress_info_ptr; /* Working data for decompression */ struct decompress_info_struct { /* * These fields shall be established by the user interface before * calling jpeg_decompress. Note that the UI must supply the storage for * the main methods struct, though it sets only a few of the methods there. */ decompress_methods_ptr methods; /* Points to list of methods to use */ external_methods_ptr emethods; /* Points to list of methods to use */ JFILEREF input_file; /* tells input routines where to read JPEG */ IFILEREF output_file; /* tells output routines where to write image */ /* these can be set at d_ui_method_selection time: */ COLOR_SPACE out_color_space; /* colorspace of output */ double output_gamma; /* image gamma wanted in output */ boolean quantize_colors; /* T if output is a colormapped format */ /* the following are ignored if not quantize_colors: */ boolean two_pass_quantize; /* use two-pass color quantization? */ boolean use_dithering; /* want color dithering? */ int desired_number_of_colors; /* number of colors to use */ boolean do_block_smoothing; /* T = apply cross-block smoothing */ boolean do_pixel_smoothing; /* T = apply post-subsampling smoothing */ /* * These fields are used for efficient buffering of data between read_jpeg_data * and the entropy decoding object. By using a shared buffer, we avoid copying * data and eliminate the need for an "unget" operation at the end of a scan. * The actual source of the data is known only to read_jpeg_data; see the * JGETC macro, below. * Note: the user interface is expected to allocate the input_buffer and * initialize bytes_in_buffer to 0. Also, for JFIF/raw-JPEG input, the UI * actually supplies the read_jpeg_data method. */ char * input_buffer; /* start of buffer (private to input code) */ char * next_input_byte; /* => next byte to read from buffer */ int bytes_in_buffer; /* # of bytes remaining in buffer */ /* * These fields are set by read_file_header or read_scan_header */ long image_width; /* overall image width */ long image_height; /* overall image height */ short data_precision; /* bits of precision in image data */ COLOR_SPACE jpeg_color_space; /* colorspace of JPEG file */ /* These three values are not used by the JPEG code, merely copied */ /* from the JFIF APP0 marker (if any). */ UINT8 density_unit; /* JFIF code for pixel size units */ UINT16 X_density; /* Horizontal pixel density */ UINT16 Y_density; /* Vertical pixel density */ short num_components; /* # of color components in JPEG image */ jpeg_component_info * comp_info; /* comp_info[i] describes component that appears i'th in SOF */ QUANT_TBL_PTR quant_tbl_ptrs[NUM_QUANT_TBLS]; /* ptrs to coefficient quantization tables, or NULL if not defined */ HUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; HUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; /* ptrs to Huffman coding tables, or NULL if not defined */ UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ boolean CCIR601_sampling; /* TRUE=first samples are cosited */ UINT16 restart_interval;/* MDUs per restart interval, or 0 for no restart */ /* * These fields are computed during jpeg_decompress startup */ short max_h_samp_factor; /* largest h_samp_factor */ short max_v_samp_factor; /* largest v_samp_factor */ short color_out_comps; /* # of color components output by color_convert */ /* (need not match num_components) */ short final_out_comps; /* # of color components in output image */ /* (1 when quantizing colors, else same as color_out_comps) */ /* * These fields are valid during any one scan */ short comps_in_scan; /* # of JPEG components input this time */ jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; /* *cur_comp_info[i] describes component that appears i'th in SOS */ long MCUs_per_row; /* # of MCUs across the image */ long MCU_rows_in_scan; /* # of MCU rows in the image */ short blocks_in_MCU; /* # of DCT blocks per MCU */ short MCU_membership[MAX_BLOCKS_IN_MCU]; /* MCU_membership[i] is index in cur_comp_info of component owning */ /* i'th block in an MCU */ /* these fields are private data for the entropy encoder */ JCOEF last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each comp */ JCOEF last_dc_diff[MAX_COMPS_IN_SCAN]; /* last DC diff for each comp */ UINT16 restarts_to_go; /* MDUs left in this restart interval */ short next_restart_num; /* # of next RSTn marker (0..7) */ }; typedef struct decompress_info_struct * decompress_info_ptr; /* Macros for reading data from the decompression input buffer */ #ifdef CHAR_IS_UNSIGNED #define JGETC(cinfo) ( --(cinfo)->bytes_in_buffer < 0 ? \ (*(cinfo)->methods->read_jpeg_data) (cinfo) : \ (int) *(cinfo)->next_input_byte++ ) #else #define JGETC(cinfo) ( --(cinfo)->bytes_in_buffer < 0 ? \ (*(cinfo)->methods->read_jpeg_data) (cinfo) : \ (int) (*(cinfo)->next_input_byte++) & 0xFF ) #endif #define JUNGETC(ch,cinfo) ((cinfo)->bytes_in_buffer++, \ *(--((cinfo)->next_input_byte)) = (ch)) #define MIN_UNGET 2 /* may always do at least 2 JUNGETCs */ /* A virtual image has a control block whose contents are private to the * memory manager module (and may differ between managers). The rest of the * code only refers to virtual images by these pointer types. */ typedef struct big_sarray_control * big_sarray_ptr; typedef struct big_barray_control * big_barray_ptr; /* Method types that need typedefs */ typedef METHOD(void, MCU_output_method_ptr, (compress_info_ptr cinfo, JBLOCK *MCU_data)); typedef METHOD(void, MCU_output_caller_ptr, (compress_info_ptr cinfo, MCU_output_method_ptr output_method)); typedef METHOD(void, subsample_ptr, (compress_info_ptr cinfo, int which_component, long input_cols, int input_rows, long output_cols, int output_rows, JSAMPARRAY above, JSAMPARRAY input_data, JSAMPARRAY below, JSAMPARRAY output_data)); typedef METHOD(void, unsubsample_ptr, (decompress_info_ptr cinfo, int which_component, long input_cols, int input_rows, long output_cols, int output_rows, JSAMPARRAY above, JSAMPARRAY input_data, JSAMPARRAY below, JSAMPARRAY output_data)); typedef METHOD(void, quantize_method_ptr, (decompress_info_ptr cinfo, int num_rows, JSAMPIMAGE input_data, JSAMPARRAY output_workspace)); typedef METHOD(void, quantize_caller_ptr, (decompress_info_ptr cinfo, quantize_method_ptr quantize_method)); /* These structs contain function pointers for the various JPEG methods. */ /* Routines to be provided by the surrounding application, rather than the * portable JPEG code proper. These are the same for compression and * decompression. */ struct external_methods_struct { /* User interface: error exit and trace message routines */ /* NOTE: the string msgtext parameters will eventually be replaced */ /* by an enumerated-type code so that non-English error messages */ /* can be substituted easily. This will not be done until all the */ /* code is in place, so that we know what messages are needed. */ METHOD(void, error_exit, (char *msgtext)); METHOD(void, trace_message, (char *msgtext)); /* Working data for error/trace facility */ /* See macros below for the usage of these variables */ int trace_level; /* level of detail of tracing messages */ /* Use level 0 for unsuppressable messages (nonfatal errors) */ /* Use levels 1, 2, 3 for successively more detailed trace options */ int message_parm[8]; /* store numeric parms for messages here */ /* Memory management */ /* NB: alloc routines never return NULL. They exit to */ /* error_exit if not successful. */ METHOD(void *, alloc_small, (size_t sizeofobject)); METHOD(void, free_small, (void *ptr)); #ifdef NEED_FAR_POINTERS /* routines for getting far-heap space */ METHOD(void FAR *, alloc_medium, (size_t sizeofobject)); METHOD(void, free_medium, (void FAR *ptr)); #else #define alloc_medium alloc_small #define free_medium free_small #endif METHOD(JSAMPARRAY, alloc_small_sarray, (long samplesperrow, long numrows)); METHOD(void, free_small_sarray, (JSAMPARRAY ptr, long numrows)); METHOD(JBLOCKARRAY, alloc_small_barray, (long blocksperrow, long numrows)); METHOD(void, free_small_barray, (JBLOCKARRAY ptr, long numrows)); METHOD(big_sarray_ptr, request_big_sarray, (long samplesperrow, long numrows, long unitheight)); METHOD(big_barray_ptr, request_big_barray, (long blocksperrow, long numrows, long unitheight)); METHOD(void, alloc_big_arrays, (long extra_small_samples, long extra_small_blocks, long extra_medium_space)); METHOD(JSAMPARRAY, access_big_sarray, (big_sarray_ptr ptr, long start_row, boolean writable)); METHOD(JBLOCKARRAY, access_big_barray, (big_barray_ptr ptr, long start_row, boolean writable)); METHOD(void, free_big_sarray, (big_sarray_ptr ptr)); METHOD(void, free_big_barray, (big_barray_ptr ptr)); }; /* Macros to simplify using the error and trace message stuff */ /* The first parameter is generally cinfo->emethods */ #define ERREXIT(emeth,msg) ((*(emeth)->error_exit) (msg)) #define ERREXIT1(emeth,msg,p1) ((emeth)->message_parm[0] = (p1), \ (*(emeth)->error_exit) (msg)) #define ERREXIT2(emeth,msg,p1,p2) ((emeth)->message_parm[0] = (p1), \ (emeth)->message_parm[1] = (p2), \ (*(emeth)->error_exit) (msg)) #define ERREXIT3(emeth,msg,p1,p2,p3) ((emeth)->message_parm[0] = (p1), \ (emeth)->message_parm[1] = (p2), \ (emeth)->message_parm[2] = (p3), \ (*(emeth)->error_exit) (msg)) #define ERREXIT4(emeth,msg,p1,p2,p3,p4) ((emeth)->message_parm[0] = (p1), \ (emeth)->message_parm[1] = (p2), \ (emeth)->message_parm[2] = (p3), \ (emeth)->message_parm[3] = (p4), \ (*(emeth)->error_exit) (msg)) #define TRACEMS(emeth,lvl,msg) \ ( (emeth)->trace_level >= (lvl) ? \ ((*(emeth)->trace_message) (msg), 0) : 0) #define TRACEMS1(emeth,lvl,msg,p1) \ ( (emeth)->trace_level >= (lvl) ? \ ((emeth)->message_parm[0] = (p1), \ (*(emeth)->trace_message) (msg), 0) : 0) #define TRACEMS2(emeth,lvl,msg,p1,p2) \ ( (emeth)->trace_level >= (lvl) ? \ ((emeth)->message_parm[0] = (p1), \ (emeth)->message_parm[1] = (p2), \ (*(emeth)->trace_message) (msg), 0) : 0) #define TRACEMS3(emeth,lvl,msg,p1,p2,p3) \ ( (emeth)->trace_level >= (lvl) ? \ ((emeth)->message_parm[0] = (p1), \ (emeth)->message_parm[1] = (p2), \ (emeth)->message_parm[2] = (p3), \ (*(emeth)->trace_message) (msg), 0) : 0) #define TRACEMS4(emeth,lvl,msg,p1,p2,p3,p4) \ ( (emeth)->trace_level >= (lvl) ? \ ((emeth)->message_parm[0] = (p1), \ (emeth)->message_parm[1] = (p2), \ (emeth)->message_parm[2] = (p3), \ (emeth)->message_parm[3] = (p4), \ (*(emeth)->trace_message) (msg), 0) : 0) #define TRACEMS8(emeth,lvl,msg,p1,p2,p3,p4,p5,p6,p7,p8) \ ( (emeth)->trace_level >= (lvl) ? \ ((emeth)->message_parm[0] = (p1), \ (emeth)->message_parm[1] = (p2), \ (emeth)->message_parm[2] = (p3), \ (emeth)->message_parm[3] = (p4), \ (emeth)->message_parm[4] = (p5), \ (emeth)->message_parm[5] = (p6), \ (emeth)->message_parm[6] = (p7), \ (emeth)->message_parm[7] = (p8), \ (*(emeth)->trace_message) (msg), 0) : 0) /* Methods used during JPEG compression. */ struct compress_methods_struct { /* Hook for user interface to get control after input_init */ METHOD(void, c_ui_method_selection, (compress_info_ptr cinfo)); /* Input image reading & conversion to standard form */ METHOD(void, input_init, (compress_info_ptr cinfo)); METHOD(void, get_input_row, (compress_info_ptr cinfo, JSAMPARRAY pixel_row)); METHOD(void, input_term, (compress_info_ptr cinfo)); /* Gamma and color space conversion */ METHOD(void, colorin_init, (compress_info_ptr cinfo)); METHOD(void, get_sample_rows, (compress_info_ptr cinfo, int rows_to_read, JSAMPIMAGE image_data)); METHOD(void, colorin_term, (compress_info_ptr cinfo)); /* Expand picture data at edges */ METHOD(void, edge_expand, (compress_info_ptr cinfo, long input_cols, int input_rows, long output_cols, int output_rows, JSAMPIMAGE image_data)); /* Subsample pixel values of a single component */ /* There can be a different subsample method for each component */ METHOD(void, subsample_init, (compress_info_ptr cinfo)); subsample_ptr subsample[MAX_COMPS_IN_SCAN]; METHOD(void, subsample_term, (compress_info_ptr cinfo)); /* Extract samples in MCU order, process & hand off to output_method */ /* The input is always exactly N MCU rows worth of data */ METHOD(void, extract_init, (compress_info_ptr cinfo)); METHOD(void, extract_MCUs, (compress_info_ptr cinfo, JSAMPIMAGE image_data, int num_mcu_rows, MCU_output_method_ptr output_method)); METHOD(void, extract_term, (compress_info_ptr cinfo)); /* Entropy encoding parameter optimization */ METHOD(void, entropy_optimize, (compress_info_ptr cinfo, MCU_output_caller_ptr source_method)); /* Entropy encoding */ METHOD(void, entropy_encoder_init, (compress_info_ptr cinfo)); METHOD(void, entropy_encode, (compress_info_ptr cinfo, JBLOCK *MCU_data)); METHOD(void, entropy_encoder_term, (compress_info_ptr cinfo)); /* JPEG file header construction */ METHOD(void, write_file_header, (compress_info_ptr cinfo)); METHOD(void, write_scan_header, (compress_info_ptr cinfo)); METHOD(void, write_jpeg_data, (compress_info_ptr cinfo, char *dataptr, int datacount)); METHOD(void, write_scan_trailer, (compress_info_ptr cinfo)); METHOD(void, write_file_trailer, (compress_info_ptr cinfo)); /* Pipeline control */ METHOD(void, c_pipeline_controller, (compress_info_ptr cinfo)); METHOD(void, entropy_output, (compress_info_ptr cinfo, char *dataptr, int datacount)); /* Overall control */ METHOD(void, c_per_scan_method_selection, (compress_info_ptr cinfo)); }; /* Methods used during JPEG decompression. */ struct decompress_methods_struct { /* Hook for user interface to get control after reading file header */ METHOD(void, d_ui_method_selection, (decompress_info_ptr cinfo)); /* JPEG file scanning */ /* Note: user interface supplies read_jpeg_data for JFIF/raw-JPEG * reading. For file formats that require random access (eg, TIFF) * the JPEG file header module will override the UI read_jpeg_data. */ METHOD(void, read_file_header, (decompress_info_ptr cinfo)); METHOD(boolean, read_scan_header, (decompress_info_ptr cinfo)); METHOD(int, read_jpeg_data, (decompress_info_ptr cinfo)); METHOD(void, read_scan_trailer, (decompress_info_ptr cinfo)); METHOD(void, read_file_trailer, (decompress_info_ptr cinfo)); /* Entropy decoding */ METHOD(void, entropy_decoder_init, (decompress_info_ptr cinfo)); METHOD(void, entropy_decode, (decompress_info_ptr cinfo, JBLOCK *MCU_data)); METHOD(void, entropy_decoder_term, (decompress_info_ptr cinfo)); /* MCU disassembly: fetch MCUs from entropy_decode, build coef array */ METHOD(void, disassemble_init, (decompress_info_ptr cinfo)); METHOD(void, disassemble_MCU, (decompress_info_ptr cinfo, JBLOCKIMAGE image_data)); METHOD(void, disassemble_term, (decompress_info_ptr cinfo)); /* Cross-block smoothing */ METHOD(void, smooth_coefficients, (decompress_info_ptr cinfo, jpeg_component_info *compptr, JBLOCKROW above, JBLOCKROW currow, JBLOCKROW below, JBLOCKROW output)); /* Un-subsample pixel values of a single component */ /* There can be a different unsubsample method for each component */ METHOD(void, unsubsample_init, (decompress_info_ptr cinfo)); unsubsample_ptr unsubsample[MAX_COMPS_IN_SCAN]; METHOD(void, unsubsample_term, (decompress_info_ptr cinfo)); /* Gamma and color space conversion */ METHOD(void, colorout_init, (decompress_info_ptr cinfo)); METHOD(void, color_convert, (decompress_info_ptr cinfo, int num_rows, JSAMPIMAGE input_data, JSAMPIMAGE output_data)); METHOD(void, colorout_term, (decompress_info_ptr cinfo)); /* Color quantization */ METHOD(void, color_quant_init, (decompress_info_ptr cinfo)); METHOD(void, color_quantize, (decompress_info_ptr cinfo, int num_rows, JSAMPIMAGE input_data, JSAMPARRAY output_data)); METHOD(void, color_quant_prescan, (decompress_info_ptr cinfo, int num_rows, JSAMPIMAGE image_data)); METHOD(void, color_quant_doit, (decompress_info_ptr cinfo, quantize_caller_ptr source_method)); METHOD(void, color_quant_term, (decompress_info_ptr cinfo)); /* Output image writing */ METHOD(void, output_init, (decompress_info_ptr cinfo)); METHOD(void, put_color_map, (decompress_info_ptr cinfo, int num_colors, JSAMPARRAY colormap)); METHOD(void, put_pixel_rows, (decompress_info_ptr cinfo, int num_rows, JSAMPIMAGE pixel_data)); METHOD(void, output_term, (decompress_info_ptr cinfo)); /* Pipeline control */ METHOD(void, d_pipeline_controller, (decompress_info_ptr cinfo)); /* Overall control */ METHOD(void, d_per_scan_method_selection, (decompress_info_ptr cinfo)); }; /* External declarations for routines that aren't called via method ptrs. */ /* Note: use "j" as first char of names to minimize namespace pollution. */ /* The PP macro hides prototype parameters from compilers that can't cope. */ #ifdef PROTO #define PP(arglist) arglist #else #define PP(arglist) () #endif /* main entry for compression */ EXTERN void jpeg_compress PP((compress_info_ptr cinfo)); /* default parameter setup for compression */ EXTERN void j_default_compression PP((compress_info_ptr cinfo, int quality)); EXTERN void j_monochrome_default PP((compress_info_ptr cinfo)); EXTERN void j_set_quality PP((compress_info_ptr cinfo, int quality, boolean force_baseline)); EXTERN void j_free_defaults PP((compress_info_ptr cinfo)); /* main entry for decompression */ EXTERN void jpeg_decompress PP((decompress_info_ptr cinfo)); /* forward DCT */ EXTERN void j_fwd_dct PP((DCTBLOCK data)); /* inverse DCT */ EXTERN void j_rev_dct PP((DCTBLOCK data)); /* utility routines in jutils.c */ EXTERN long jround_up PP((long a, long b)); EXTERN void jcopy_sample_rows PP((JSAMPARRAY input_array, int source_row, JSAMPARRAY output_array, int dest_row, int num_rows, long num_cols)); EXTERN void jcopy_block_row PP((JBLOCKROW input_row, JBLOCKROW output_row, long num_blocks)); EXTERN void jzero_far PP((void FAR * target, size_t bytestozero)); /* method selection routines for compression modules */ EXTERN void jselcpipeline PP((compress_info_ptr cinfo)); /* jcpipe.c */ EXTERN void jselchuffman PP((compress_info_ptr cinfo)); /* jchuff.c */ EXTERN void jselcarithmetic PP((compress_info_ptr cinfo)); /* jcarith.c */ EXTERN void jselexpand PP((compress_info_ptr cinfo)); /* jcexpand.c */ EXTERN void jselsubsample PP((compress_info_ptr cinfo)); /* jcsample.c */ EXTERN void jselcmcu PP((compress_info_ptr cinfo)); /* jcmcu.c */ EXTERN void jselccolor PP((compress_info_ptr cinfo)); /* jccolor.c */ /* The user interface should call one of these to select input format: */ EXTERN void jselrgif PP((compress_info_ptr cinfo)); /* jrdgif.c */ EXTERN void jselrppm PP((compress_info_ptr cinfo)); /* jrdppm.c */ EXTERN void jselrsun PP((compress_info_ptr cinfo)); /* jrdsun.c */ /* and one of these to select output header format: */ EXTERN void jselwjfif PP((compress_info_ptr cinfo)); /* jwrjfif.c */ /* method selection routines for decompression modules */ EXTERN void jseldpipeline PP((decompress_info_ptr cinfo)); /* jdpipe.c */ EXTERN void jseldhuffman PP((decompress_info_ptr cinfo)); /* jdhuff.c */ EXTERN void jseldarithmetic PP((decompress_info_ptr cinfo)); /* jdarith.c */ EXTERN void jseldmcu PP((decompress_info_ptr cinfo)); /* jdmcu.c */ EXTERN void jselbsmooth PP((decompress_info_ptr cinfo)); /* jbsmooth.c */ EXTERN void jselunsubsample PP((decompress_info_ptr cinfo)); /* jdsample.c */ EXTERN void jseldcolor PP((decompress_info_ptr cinfo)); /* jdcolor.c */ EXTERN void jsel1quantize PP((decompress_info_ptr cinfo)); /* jquant1.c */ EXTERN void jsel2quantize PP((decompress_info_ptr cinfo)); /* jquant2.c */ /* The user interface should call one of these to select input format: */ EXTERN void jselrjfif PP((decompress_info_ptr cinfo)); /* jrdjfif.c */ /* and one of these to select output image format: */ EXTERN void jselwgif PP((decompress_info_ptr cinfo)); /* jwrgif.c */ EXTERN void jselwppm PP((decompress_info_ptr cinfo)); /* jwrppm.c */ EXTERN void jselwsun PP((decompress_info_ptr cinfo)); /* jwrsun.c */ /* method selection routines for system-dependent modules */ EXTERN void jselerror PP((external_methods_ptr emethods)); /* jerror.c */ EXTERN void jselvirtmem PP((external_methods_ptr emethods)); /* jvirtmem.c */ /* debugging hook in jvirtmem.c */ #ifdef MEM_STATS EXTERN void j_mem_stats PP((void)); #endif /* Miscellaneous useful macros */ #define MAX(a,b) ((a) > (b) ? (a) : (b)) #define MIN(a,b) ((a) < (b) ? (a) : (b)) #define RST0 0xD0 /* RST0 marker code */