JezK
Edit File: jpegint.h
/* * jpegint.h * * This file was part of the Independent JPEG Group's software: * Copyright (C) 1991-1997, Thomas G. Lane. * Modified 1997-2009 by Guido Vollbeding. * libjpeg-turbo Modifications: * Copyright (C) 2015-2016, 2019, 2021, D. R. Commander. * Copyright (C) 2015, Google, Inc. * Copyright (C) 2021, Alex Richardson. * For conditions of distribution and use, see the accompanying README.ijg * 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 */ /* JLONG must hold at least signed 32-bit values. */ typedef long JLONG; /* JUINTPTR must hold pointer values. */ #ifdef __UINTPTR_TYPE__ /* * __UINTPTR_TYPE__ is GNU-specific and available in GCC 4.6+ and Clang 3.0+. * Fortunately, that is sufficient to support the few architectures for which * sizeof(void *) != sizeof(size_t). The only other options would require C99 * or Clang-specific builtins. */ typedef __UINTPTR_TYPE__ JUINTPTR; #else typedef size_t JUINTPTR; #endif /* * Left shift macro that handles a negative operand without causing any * sanitizer warnings */ #define LEFT_SHIFT(a, b) ((JLONG)((unsigned long)(a) << (b))) /* Declarations for compression modules */ /* Master control module */ struct jpeg_comp_master { void (*prepare_for_pass) (j_compress_ptr cinfo); void (*pass_startup) (j_compress_ptr cinfo); void (*finish_pass) (j_compress_ptr cinfo); /* State variables made visible to other modules */ boolean call_pass_startup; /* True if pass_startup must be called */ boolean is_last_pass; /* True during last pass */ }; /* Main buffer control (downsampled-data buffer) */ struct jpeg_c_main_controller { void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode); void (*process_data) (j_compress_ptr cinfo, JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail); }; /* Compression preprocessing (downsampling input buffer control) */ struct jpeg_c_prep_controller { void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode); void (*pre_process_data) (j_compress_ptr cinfo, JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail, JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr, JDIMENSION out_row_groups_avail); }; /* Coefficient buffer control */ struct jpeg_c_coef_controller { void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode); boolean (*compress_data) (j_compress_ptr cinfo, JSAMPIMAGE input_buf); }; /* Colorspace conversion */ struct jpeg_color_converter { void (*start_pass) (j_compress_ptr cinfo); void (*color_convert) (j_compress_ptr cinfo, JSAMPARRAY input_buf, JSAMPIMAGE output_buf, JDIMENSION output_row, int num_rows); }; /* Downsampling */ struct jpeg_downsampler { void (*start_pass) (j_compress_ptr cinfo); void (*downsample) (j_compress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION in_row_index, JSAMPIMAGE output_buf, JDIMENSION out_row_group_index); boolean need_context_rows; /* TRUE if need rows above & below */ }; /* Forward DCT (also controls coefficient quantization) */ struct jpeg_forward_dct { void (*start_pass) (j_compress_ptr cinfo); /* perhaps this should be an array??? */ void (*forward_DCT) (j_compress_ptr cinfo, jpeg_component_info *compptr, JSAMPARRAY sample_data, JBLOCKROW coef_blocks, JDIMENSION start_row, JDIMENSION start_col, JDIMENSION num_blocks); }; /* Entropy encoding */ struct jpeg_entropy_encoder { void (*start_pass) (j_compress_ptr cinfo, boolean gather_statistics); boolean (*encode_mcu) (j_compress_ptr cinfo, JBLOCKROW *MCU_data); void (*finish_pass) (j_compress_ptr cinfo); }; /* Marker writing */ struct jpeg_marker_writer { void (*write_file_header) (j_compress_ptr cinfo); void (*write_frame_header) (j_compress_ptr cinfo); void (*write_scan_header) (j_compress_ptr cinfo); void (*write_file_trailer) (j_compress_ptr cinfo); void (*write_tables_only) (j_compress_ptr cinfo); /* These routines are exported to allow insertion of extra markers */ /* Probably only COM and APPn markers should be written this way */ void (*write_marker_header) (j_compress_ptr cinfo, int marker, unsigned int datalen); void (*write_marker_byte) (j_compress_ptr cinfo, int val); }; /* Declarations for decompression modules */ /* Master control module */ struct jpeg_decomp_master { void (*prepare_for_output_pass) (j_decompress_ptr cinfo); void (*finish_output_pass) (j_decompress_ptr cinfo); /* State variables made visible to other modules */ boolean is_dummy_pass; /* True during 1st pass for 2-pass quant */ /* Partial decompression variables */ JDIMENSION first_iMCU_col; JDIMENSION last_iMCU_col; JDIMENSION first_MCU_col[MAX_COMPONENTS]; JDIMENSION last_MCU_col[MAX_COMPONENTS]; boolean jinit_upsampler_no_alloc; /* Last iMCU row that was successfully decoded */ JDIMENSION last_good_iMCU_row; }; /* Input control module */ struct jpeg_input_controller { int (*consume_input) (j_decompress_ptr cinfo); void (*reset_input_controller) (j_decompress_ptr cinfo); void (*start_input_pass) (j_decompress_ptr cinfo); 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 { void (*start_pass) (j_decompress_ptr cinfo, J_BUF_MODE pass_mode); 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 { void (*start_input_pass) (j_decompress_ptr cinfo); int (*consume_data) (j_decompress_ptr cinfo); void (*start_output_pass) (j_decompress_ptr cinfo); 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 { void (*start_pass) (j_decompress_ptr cinfo, J_BUF_MODE pass_mode); 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 { 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. */ 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 { void (*start_pass) (j_decompress_ptr cinfo); 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 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 { 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 { void (*start_pass) (j_decompress_ptr cinfo); 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 { void (*start_pass) (j_decompress_ptr cinfo); 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 { void (*start_pass) (j_decompress_ptr cinfo, boolean is_pre_scan); void (*color_quantize) (j_decompress_ptr cinfo, JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows); void (*finish_pass) (j_decompress_ptr cinfo); 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 a JLONG 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 JLONG shift_temp; #define RIGHT_SHIFT(x, shft) \ ((shift_temp = (x)) < 0 ? \ (shift_temp >> (shft)) | ((~((JLONG)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(j_compress_ptr cinfo); EXTERN(void) jinit_c_master_control(j_compress_ptr cinfo, boolean transcode_only); EXTERN(void) jinit_c_main_controller(j_compress_ptr cinfo, boolean need_full_buffer); EXTERN(void) jinit_c_prep_controller(j_compress_ptr cinfo, boolean need_full_buffer); EXTERN(void) jinit_c_coef_controller(j_compress_ptr cinfo, boolean need_full_buffer); EXTERN(void) jinit_color_converter(j_compress_ptr cinfo); EXTERN(void) jinit_downsampler(j_compress_ptr cinfo); EXTERN(void) jinit_forward_dct(j_compress_ptr cinfo); EXTERN(void) jinit_huff_encoder(j_compress_ptr cinfo); EXTERN(void) jinit_phuff_encoder(j_compress_ptr cinfo); EXTERN(void) jinit_arith_encoder(j_compress_ptr cinfo); EXTERN(void) jinit_marker_writer(j_compress_ptr cinfo); /* Decompression module initialization routines */ EXTERN(void) jinit_master_decompress(j_decompress_ptr cinfo); EXTERN(void) jinit_d_main_controller(j_decompress_ptr cinfo, boolean need_full_buffer); EXTERN(void) jinit_d_coef_controller(j_decompress_ptr cinfo, boolean need_full_buffer); EXTERN(void) jinit_d_post_controller(j_decompress_ptr cinfo, boolean need_full_buffer); EXTERN(void) jinit_input_controller(j_decompress_ptr cinfo); EXTERN(void) jinit_marker_reader(j_decompress_ptr cinfo); EXTERN(void) jinit_huff_decoder(j_decompress_ptr cinfo); EXTERN(void) jinit_phuff_decoder(j_decompress_ptr cinfo); EXTERN(void) jinit_arith_decoder(j_decompress_ptr cinfo); EXTERN(void) jinit_inverse_dct(j_decompress_ptr cinfo); EXTERN(void) jinit_upsampler(j_decompress_ptr cinfo); EXTERN(void) jinit_color_deconverter(j_decompress_ptr cinfo); EXTERN(void) jinit_1pass_quantizer(j_decompress_ptr cinfo); EXTERN(void) jinit_2pass_quantizer(j_decompress_ptr cinfo); EXTERN(void) jinit_merged_upsampler(j_decompress_ptr cinfo); /* Memory manager initialization */ EXTERN(void) jinit_memory_mgr(j_common_ptr cinfo); /* Utility routines in jutils.c */ EXTERN(long) jdiv_round_up(long a, long b); EXTERN(long) jround_up(long a, long b); EXTERN(void) jcopy_sample_rows(JSAMPARRAY input_array, int source_row, JSAMPARRAY output_array, int dest_row, int num_rows, JDIMENSION num_cols); EXTERN(void) jcopy_block_row(JBLOCKROW input_row, JBLOCKROW output_row, JDIMENSION num_blocks); EXTERN(void) jzero_far(void *target, size_t bytestozero); /* 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 */ /* Arithmetic coding probability estimation tables in jaricom.c */ extern const JLONG jpeg_aritab[];