/* * jpegint.h * * Copyright (C) 1991-1997, 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 provides common declarations for the various JPEG modules. * These declarations are considered internal to the JPEG library; most * applications using the library shouldn't need to include this file. */ /* Declarations for both compression & decompression */ typedef enum { /* Operating modes for buffer controllers */ JBUF_PASS_THRU, /* Plain stripwise operation */ /* Remaining modes require a full-image buffer to have been created */ JBUF_SAVE_SOURCE, /* Run source subobject only, save output */ JBUF_CRANK_DEST, /* Run dest subobject only, using saved data */ JBUF_SAVE_AND_PASS /* Run both subobjects, save output */ } J_BUF_MODE; /* Values of global_state field (jdapi.c has some dependencies on ordering!) */ #define CSTATE_START 100 /* after create_compress */ #define CSTATE_SCANNING 101 /* start_compress done, write_scanlines OK */ #define CSTATE_RAW_OK 102 /* start_compress done, write_raw_data OK */ #define CSTATE_WRCOEFS 103 /* jpeg_write_coefficients done */ #define DSTATE_START 200 /* after create_decompress */ #define DSTATE_INHEADER 201 /* reading header markers, no SOS yet */ #define DSTATE_READY 202 /* found SOS, ready for start_decompress */ #define DSTATE_PRELOAD 203 /* reading multiscan file in start_decompress*/ #define DSTATE_PRESCAN 204 /* performing dummy pass for 2-pass quant */ #define DSTATE_SCANNING 205 /* start_decompress done, read_scanlines OK */ //#define DSTATE_RAW_OK 206 /* start_decompress done, read_raw_data OK */ //#define DSTATE_BUFIMAGE 207 /* expecting jpeg_start_output */ #define DSTATE_BUFPOST 208 /* looking for SOS/EOI in jpeg_finish_output */ #define DSTATE_RDCOEFS 209 /* reading file in jpeg_read_coefficients */ #define DSTATE_STOPPING 210 /* looking for EOI in jpeg_finish_decompress */ /* Declarations for decompression modules */ /* Master control module */ struct jpeg_decomp_master { JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo)); JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo)); }; /* Input control module */ struct jpeg_input_controller { JMETHOD(int, consume_input, (j_decompress_ptr cinfo)); JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo)); JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo)); JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo)); /* State variables made visible to other modules */ boolean has_multiple_scans; /* True if file has multiple scans */ boolean eoi_reached; /* True when EOI has been consumed */ }; /* Main buffer control (downsampled-data buffer) */ struct jpeg_d_main_controller { JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); JMETHOD(void, process_data, (j_decompress_ptr cinfo, JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail)); }; /* Coefficient buffer control */ struct jpeg_d_coef_controller { JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo)); JMETHOD(int, consume_data, (j_decompress_ptr cinfo)); JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo)); JMETHOD(int, decompress_data, (j_decompress_ptr cinfo, JSAMPIMAGE output_buf)); /* Pointer to array of coefficient virtual arrays, or NULL if none */ jvirt_barray_ptr *coef_arrays; }; /* Decompression postprocessing (color quantization buffer control) */ struct jpeg_d_post_controller { JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); JMETHOD(void, post_process_data, (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, JDIMENSION in_row_groups_avail, JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail)); }; /* Marker reading & parsing */ struct jpeg_marker_reader { JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo)); /* Read markers until SOS or EOI. * Returns same codes as are defined for jpeg_consume_input: * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. */ JMETHOD(int, read_markers, (j_decompress_ptr cinfo)); /* Read a restart marker --- exported for use by entropy decoder only */ jpeg_marker_parser_method read_restart_marker; /* State of marker reader --- nominally internal, but applications * supplying COM or APPn handlers might like to know the state. */ boolean saw_SOI; /* found SOI? */ boolean saw_SOF; /* found SOF? */ int next_restart_num; /* next restart number expected (0-7) */ unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */ }; /* Entropy decoding */ struct jpeg_entropy_decoder { JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)); /* This is here to share code between baseline and progressive decoders; */ /* other modules probably should not use it */ boolean insufficient_data; /* set TRUE after emitting warning */ }; /* Inverse DCT (also performs dequantization) */ typedef JMETHOD(void, inverse_DCT_method_ptr, (j_decompress_ptr cinfo, jpeg_component_info * compptr, JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col)); struct jpeg_inverse_dct { JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); /* It is useful to allow each component to have a separate IDCT method. */ inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS]; }; /* Upsampling (note that upsampler must also call color converter) */ struct jpeg_upsampler { JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); JMETHOD(void, upsample, (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, JDIMENSION in_row_groups_avail, JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail)); boolean need_context_rows; /* TRUE if need rows above & below */ }; /* Colorspace conversion */ struct jpeg_color_deconverter { JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); JMETHOD(void, color_convert, (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION input_row, JSAMPARRAY output_buf, int num_rows)); }; /* Color quantization or color precision reduction */ struct jpeg_color_quantizer { JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan)); JMETHOD(void, color_quantize, (j_decompress_ptr cinfo, JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows)); JMETHOD(void, finish_pass, (j_decompress_ptr cinfo)); JMETHOD(void, new_color_map, (j_decompress_ptr cinfo)); }; /* Miscellaneous useful macros */ #undef MAX #define MAX(a,b) ((a) > (b) ? (a) : (b)) #undef MIN #define MIN(a,b) ((a) < (b) ? (a) : (b)) /* We assume that right shift corresponds to signed division by 2 with * rounding towards minus infinity. This is correct for typical "arithmetic * shift" instructions that shift in copies of the sign bit. But some * C compilers implement >> with an unsigned shift. For these machines you * must define RIGHT_SHIFT_IS_UNSIGNED. * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity. * It is only applied with constant shift counts. SHIFT_TEMPS must be * included in the variables of any routine using RIGHT_SHIFT. */ #ifdef RIGHT_SHIFT_IS_UNSIGNED #define SHIFT_TEMPS INT32 shift_temp; #define RIGHT_SHIFT(x,shft) \ ((shift_temp = (x)) < 0 ? \ (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \ (shift_temp >> (shft))) #else #define SHIFT_TEMPS #define RIGHT_SHIFT(x,shft) ((x) >> (shft)) #endif /* Compression module initialization routines */ EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo)); EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo, boolean transcode_only)); EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo, boolean need_full_buffer)); EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo, boolean need_full_buffer)); EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo, boolean need_full_buffer)); EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo)); EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo)); EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo)); EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo)); EXTERN(void) jinit_phuff_encoder JPP((j_compress_ptr cinfo)); EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo)); /* Decompression module initialization routines */ EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo)); EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo, boolean need_full_buffer)); EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo, boolean need_full_buffer)); EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo, boolean need_full_buffer)); EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo)); EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo)); EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo)); EXTERN(void) jinit_phuff_decoder JPP((j_decompress_ptr cinfo)); EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo)); EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo)); EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo)); EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo)); EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo)); EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo)); /* Memory manager initialization */ EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo)); /* Utility routines in jutils.c */ static INLINE long jdiv_round_up (long a, long b) /* Compute a/b rounded up to next integer, ie, ceil(a/b) */ /* Assumes a >= 0, b > 0 */ { return (a + b - 1L) / b; } static INLINE long jround_up (long a, long b) /* Compute a rounded up to next multiple of b, ie, ceil(a/b)*b */ /* Assumes a >= 0, b > 0 */ { a += b - 1L; return a - (a % b); } EXTERN(long) jround_up JPP((long a, long b)); EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row, JSAMPARRAY output_array, int dest_row, int num_rows, JDIMENSION num_cols)); /* Constant tables in jutils.c */ #if 0 /* This table is not actually needed in v6a */ extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */ #endif extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */