96 lines
2.7 KiB
Plaintext
96 lines
2.7 KiB
Plaintext
unit imjcinit;
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{ Original: jcinit.c ; Copyright (C) 1991-1997, Thomas G. Lane. }
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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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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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interface
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{$I imjconfig.inc}
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uses
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imjinclude,
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imjdeferr,
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imjerror,
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imjpeglib,
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{$ifdef C_PROGRESSIVE_SUPPORTED}
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imjcphuff,
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{$endif}
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imjchuff, imjcmaster, imjccolor, imjcsample, imjcprepct,
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imjcdctmgr, imjccoefct, imjcmainct, imjcmarker;
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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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{GLOBAL}
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procedure jinit_compress_master (cinfo : j_compress_ptr);
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implementation
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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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{GLOBAL}
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procedure jinit_compress_master (cinfo : j_compress_ptr);
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begin
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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 (not cinfo^.raw_data_in) then
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begin
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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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end;
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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) then
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begin
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ERREXIT(j_common_ptr(cinfo), JERR_ARITH_NOTIMPL);
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end
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else
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begin
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if (cinfo^.progressive_mode) then
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begin
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{$ifdef C_PROGRESSIVE_SUPPORTED}
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jinit_phuff_encoder(cinfo);
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{$else}
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ERREXIT(j_common_ptr(cinfo), JERR_NOT_COMPILED);
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{$endif}
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end
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else
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jinit_huff_encoder(cinfo);
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end;
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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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(cinfo^.num_scans > 1) or (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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cinfo^.marker^.write_file_header (cinfo);
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end;
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end.
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