diff options
Diffstat (limited to 'packages/pasjpeg/src/jcomapi.pas')
-rw-r--r-- | packages/pasjpeg/src/jcomapi.pas | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/packages/pasjpeg/src/jcomapi.pas b/packages/pasjpeg/src/jcomapi.pas new file mode 100644 index 0000000000..40b2b3826f --- /dev/null +++ b/packages/pasjpeg/src/jcomapi.pas @@ -0,0 +1,130 @@ +Unit JCOMapi; + +{ This file contains application interface routines that are used for both + compression and decompression. } + +{ Original: jcomapi.c; Copyright (C) 1994-1997, Thomas G. Lane. } + +interface + +{$I jconfig.inc} + +uses + jmorecfg, + jinclude, + jpeglib; + +{ Abort processing of a JPEG compression or decompression operation, + but don't destroy the object itself. } + +{GLOBAL} +procedure jpeg_abort (cinfo : j_common_ptr); + + +{ Destruction of a JPEG object. } + +{GLOBAL} +procedure jpeg_destroy (cinfo : j_common_ptr); + +{GLOBAL} +function jpeg_alloc_quant_table (cinfo : j_common_ptr) : JQUANT_TBL_PTR; + +{GLOBAL} +function jpeg_alloc_huff_table (cinfo : j_common_ptr) : JHUFF_TBL_PTR; + +implementation + +{ Abort processing of a JPEG compression or decompression operation, + but don't destroy the object itself. + + For this, we merely clean up all the nonpermanent memory pools. + Note that temp files (virtual arrays) are not allowed to belong to + the permanent pool, so we will be able to close all temp files here. + Closing a data source or destination, if necessary, is the application's + responsibility. } + + +{GLOBAL} +procedure jpeg_abort (cinfo : j_common_ptr); +var + pool : int; +begin + { Do nothing if called on a not-initialized or destroyed JPEG object. } + if (cinfo^.mem = NIL) then + exit; + + { Releasing pools in reverse order might help avoid fragmentation + with some (brain-damaged) malloc libraries. } + + for pool := JPOOL_NUMPOOLS-1 downto JPOOL_PERMANENT+1 do + begin + cinfo^.mem^.free_pool (cinfo, pool); + end; + + { Reset overall state for possible reuse of object } + if (cinfo^.is_decompressor) then + begin + cinfo^.global_state := DSTATE_START; + { Try to keep application from accessing now-deleted marker list. + A bit kludgy to do it here, but this is the most central place. } + j_decompress_ptr(cinfo)^.marker_list := NIL; + end + else + begin + cinfo^.global_state := CSTATE_START; + end; +end; + + +{ Destruction of a JPEG object. + + Everything gets deallocated except the master jpeg_compress_struct itself + and the error manager struct. Both of these are supplied by the application + and must be freed, if necessary, by the application. (Often they are on + the stack and so don't need to be freed anyway.) + Closing a data source or destination, if necessary, is the application's + responsibility. } + + +{GLOBAL} +procedure jpeg_destroy (cinfo : j_common_ptr); +begin + { We need only tell the memory manager to release everything. } + { NB: mem pointer is NIL if memory mgr failed to initialize. } + if (cinfo^.mem <> NIL) then + cinfo^.mem^.self_destruct (cinfo); + cinfo^.mem := NIL; { be safe if jpeg_destroy is called twice } + cinfo^.global_state := 0; { mark it destroyed } +end; + + +{ Convenience routines for allocating quantization and Huffman tables. + (Would jutils.c be a more reasonable place to put these?) } + + +{GLOBAL} +function jpeg_alloc_quant_table (cinfo : j_common_ptr) : JQUANT_TBL_PTR; +var + tbl : JQUANT_TBL_PTR; +begin + tbl := JQUANT_TBL_PTR( + cinfo^.mem^.alloc_small (cinfo, JPOOL_PERMANENT, SIZEOF(JQUANT_TBL)) + ); + tbl^.sent_table := FALSE; { make sure this is false in any new table } + jpeg_alloc_quant_table := tbl; +end; + + +{GLOBAL} +function jpeg_alloc_huff_table (cinfo : j_common_ptr) : JHUFF_TBL_PTR; +var + tbl : JHUFF_TBL_PTR; +begin + tbl := JHUFF_TBL_PTR( + cinfo^.mem^.alloc_small (cinfo, JPOOL_PERMANENT, SIZEOF(JHUFF_TBL)) + ); + tbl^.sent_table := FALSE; { make sure this is false in any new table } + jpeg_alloc_huff_table := tbl; +end; + +end. |