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/*
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 * jcinit.c
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 *
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 * Copyright (C) 1991-1997, Thomas G. Lane.
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 * This file is part of the Independent JPEG Group's software.
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 * For conditions of distribution and use, see the accompanying README file.
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 *
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 * This file contains initialization logic for the JPEG compressor.
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 * This routine is in charge of selecting the modules to be executed and
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 * making an initialization call to each one.
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 *
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 * Logically, this code belongs in jcmaster.c.  It's split out because
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 * linking this routine implies linking the entire compression library.
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 * For a transcoding-only application, we want to be able to use jcmaster.c
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 * without linking in the whole library.
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 */
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#define JPEG_INTERNALS
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#include "jinclude.h"
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#include "jpeglib.h"
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/*
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 * Master selection of compression modules.
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 * This is done once at the start of processing an image.  We determine
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 * which modules will be used and give them appropriate initialization calls.
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 */
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GLOBAL(void)
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jinit_compress_master (j_compress_ptr cinfo)
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{
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  /* Initialize master control (includes parameter checking/processing) */
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  jinit_c_master_control(cinfo, FALSE /* full compression */);
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  /* Preprocessing */
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  if (! cinfo->raw_data_in) {
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    jinit_color_converter(cinfo);
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    jinit_downsampler(cinfo);
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    jinit_c_prep_controller(cinfo, FALSE /* never need full buffer here */);
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  }
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  /* Forward DCT */
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  jinit_forward_dct(cinfo);
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  /* Entropy encoding: either Huffman or arithmetic coding. */
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  if (cinfo->arith_code) {
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    ERREXIT(cinfo, JERR_ARITH_NOTIMPL);
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  } else {
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    if (cinfo->progressive_mode) {
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#ifdef C_PROGRESSIVE_SUPPORTED
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      jinit_phuff_encoder(cinfo);
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#else
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      ERREXIT(cinfo, JERR_NOT_COMPILED);
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#endif
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    } else
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      jinit_huff_encoder(cinfo);
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  }
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  /* Need a full-image coefficient buffer in any multi-pass mode. */
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  jinit_c_coef_controller(cinfo,
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		(boolean) (cinfo->num_scans > 1 || cinfo->optimize_coding));
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  jinit_c_main_controller(cinfo, FALSE /* never need full buffer here */);
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  jinit_marker_writer(cinfo);
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  /* We can now tell the memory manager to allocate virtual arrays. */
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  (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);
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  /* Write the datastream header (SOI) immediately.
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   * Frame and scan headers are postponed till later.
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   * This lets application insert special markers after the SOI.
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   */
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  (*cinfo->marker->write_file_header) (cinfo);
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}
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