jcinit.c (5186B)
1 /* 2 * jcinit.c 3 * 4 * This file was part of the Independent JPEG Group's software: 5 * Copyright (C) 1991-1997, Thomas G. Lane. 6 * Lossless JPEG Modifications: 7 * Copyright (C) 1999, Ken Murchison. 8 * libjpeg-turbo Modifications: 9 * Copyright (C) 2020, 2022, D. R. Commander. 10 * For conditions of distribution and use, see the accompanying README.ijg 11 * file. 12 * 13 * This file contains initialization logic for the JPEG compressor. 14 * This routine is in charge of selecting the modules to be executed and 15 * making an initialization call to each one. 16 * 17 * Logically, this code belongs in jcmaster.c. It's split out because 18 * linking this routine implies linking the entire compression library. 19 * For a transcoding-only application, we want to be able to use jcmaster.c 20 * without linking in the whole library. 21 */ 22 23 #define JPEG_INTERNALS 24 #include "jinclude.h" 25 #include "jpeglib.h" 26 #include "jpegapicomp.h" 27 28 29 /* 30 * Master selection of compression modules. 31 * This is done once at the start of processing an image. We determine 32 * which modules will be used and give them appropriate initialization calls. 33 */ 34 35 GLOBAL(void) 36 jinit_compress_master(j_compress_ptr cinfo) 37 { 38 /* Initialize master control (includes parameter checking/processing) */ 39 jinit_c_master_control(cinfo, FALSE /* full compression */); 40 41 /* Preprocessing */ 42 if (!cinfo->raw_data_in) { 43 if (cinfo->data_precision == 16) { 44 #ifdef C_LOSSLESS_SUPPORTED 45 j16init_color_converter(cinfo); 46 j16init_downsampler(cinfo); 47 j16init_c_prep_controller(cinfo, 48 FALSE /* never need full buffer here */); 49 #else 50 ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision); 51 #endif 52 } else if (cinfo->data_precision == 12) { 53 j12init_color_converter(cinfo); 54 j12init_downsampler(cinfo); 55 j12init_c_prep_controller(cinfo, 56 FALSE /* never need full buffer here */); 57 } else { 58 jinit_color_converter(cinfo); 59 jinit_downsampler(cinfo); 60 jinit_c_prep_controller(cinfo, FALSE /* never need full buffer here */); 61 } 62 } 63 64 if (cinfo->master->lossless) { 65 #ifdef C_LOSSLESS_SUPPORTED 66 /* Prediction, sample differencing, and point transform */ 67 if (cinfo->data_precision == 16) 68 j16init_lossless_compressor(cinfo); 69 else if (cinfo->data_precision == 12) 70 j12init_lossless_compressor(cinfo); 71 else 72 jinit_lossless_compressor(cinfo); 73 /* Entropy encoding: either Huffman or arithmetic coding. */ 74 if (cinfo->arith_code) { 75 ERREXIT(cinfo, JERR_ARITH_NOTIMPL); 76 } else { 77 jinit_lhuff_encoder(cinfo); 78 } 79 80 /* Need a full-image difference buffer in any multi-pass mode. */ 81 if (cinfo->data_precision == 16) 82 j16init_c_diff_controller(cinfo, (boolean)(cinfo->num_scans > 1 || 83 cinfo->optimize_coding)); 84 else if (cinfo->data_precision == 12) 85 j12init_c_diff_controller(cinfo, (boolean)(cinfo->num_scans > 1 || 86 cinfo->optimize_coding)); 87 else 88 jinit_c_diff_controller(cinfo, (boolean)(cinfo->num_scans > 1 || 89 cinfo->optimize_coding)); 90 #else 91 ERREXIT(cinfo, JERR_NOT_COMPILED); 92 #endif 93 } else { 94 if (cinfo->data_precision == 16) 95 ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision); 96 /* Forward DCT */ 97 if (cinfo->data_precision == 12) 98 j12init_forward_dct(cinfo); 99 else 100 jinit_forward_dct(cinfo); 101 /* Entropy encoding: either Huffman or arithmetic coding. */ 102 if (cinfo->arith_code) { 103 #ifdef C_ARITH_CODING_SUPPORTED 104 jinit_arith_encoder(cinfo); 105 #else 106 ERREXIT(cinfo, JERR_ARITH_NOTIMPL); 107 #endif 108 } else { 109 if (cinfo->progressive_mode) { 110 #ifdef C_PROGRESSIVE_SUPPORTED 111 jinit_phuff_encoder(cinfo); 112 #else 113 ERREXIT(cinfo, JERR_NOT_COMPILED); 114 #endif 115 } else 116 jinit_huff_encoder(cinfo); 117 } 118 119 /* Need a full-image coefficient buffer in any multi-pass mode. */ 120 if (cinfo->data_precision == 12) 121 j12init_c_coef_controller(cinfo, (boolean)(cinfo->num_scans > 1 || 122 cinfo->optimize_coding)); 123 else 124 jinit_c_coef_controller(cinfo, (boolean)(cinfo->num_scans > 1 || 125 cinfo->optimize_coding)); 126 } 127 128 if (cinfo->data_precision == 16) 129 #ifdef C_LOSSLESS_SUPPORTED 130 j16init_c_main_controller(cinfo, FALSE /* never need full buffer here */); 131 #else 132 ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision); 133 #endif 134 else if (cinfo->data_precision == 12) 135 j12init_c_main_controller(cinfo, FALSE /* never need full buffer here */); 136 else 137 jinit_c_main_controller(cinfo, FALSE /* never need full buffer here */); 138 139 jinit_marker_writer(cinfo); 140 141 /* We can now tell the memory manager to allocate virtual arrays. */ 142 (*cinfo->mem->realize_virt_arrays) ((j_common_ptr)cinfo); 143 144 /* Write the datastream header (SOI) immediately. 145 * Frame and scan headers are postponed till later. 146 * This lets application insert special markers after the SOI. 147 */ 148 (*cinfo->marker->write_file_header) (cinfo); 149 }