tif_ojpeg.c

一个国人自己实现图像库的程序（有参考价值）

#include "tiffiop.h"
#ifdef OJPEG_SUPPORT

/* JPEG Compression support, as per the original TIFF 6.0 specification.

   WARNING: KLUDGE ALERT!  The type of JPEG encapsulation defined by the TIFF
                           Version 6.0 specification is now totally obsolete and
   deprecated for new applications and images.  This file is an unsupported hack
   that was created solely in order to read (but NOT write!) a few old,
   unconverted images still present on some users' computer systems.  The code
   isn't pretty or robust, and it won't read every "old format" JPEG-in-TIFF
   file (see Samuel Leffler's draft "TIFF Technical Note No. 2" for a long and
   incomplete list of known problems), but it seems to work well enough in the
   few cases of practical interest to the author; so, "caveat emptor"!  This
   file should NEVER be enhanced to write new images using anything other than
   the latest approved JPEG-in-TIFF encapsulation method, implemented by the
   "tif_jpeg.c" file elsewhere in this library.

   This file interfaces with Release 6B of the JPEG Library written by theu
   Independent JPEG Group, which you can find on the Internet at:
   ftp.uu.net:/graphics/jpeg/.

   Contributed by Scott Marovich <[e-mail]> with considerable help
   from Charles Auer <[e-mail]> to unravel the mysteries of image files
   created by Microsoft's Wang Imaging application.
*/
#include <setjmp.h>
#include <stdio.h>
#ifdef FAR
#undef FAR /* Undefine FAR to avoid conflict with JPEG definition */
#endif
#define JPEG_INTERNALS /* Include "jpegint.h" for "DSTATE_*" symbols */
#undef INLINE
#include "..\jpeg\jpeglib.h"
#undef JPEG_INTERNALS

/* Hack for Microsoft's Wang Imaging for Windows output files */
extern void jpeg_reset_huff_decode(j_decompress_ptr,float *);

/* On some machines, it may be worthwhile to use "_setjmp()" or "sigsetjmp()"
   instead of "setjmp()".  These macros make it easier:
*/
#define SETJMP(jbuf)setjmp(jbuf)
#define LONGJMP(jbuf,code)longjmp(jbuf,code)
#define JMP_BUF jmp_buf

#define TIFFTAG_WANG_PAGECONTROL 32934

/* Bit-vector offsets for keeping track of TIFF records that we've parsed. */

#define FIELD_JPEGPROC FIELD_CODEC
#define FIELD_JPEGIFOFFSET (FIELD_CODEC+1)
#define FIELD_JPEGIFBYTECOUNT (FIELD_CODEC+2)
#define FIELD_JPEGRESTARTINTERVAL (FIELD_CODEC+3)
#define FIELD_JPEGTABLES (FIELD_CODEC+4) /* New, post-6.0 JPEG-in-TIFF tag! */
#define FIELD_JPEGLOSSLESSPREDICTORS (FIELD_CODEC+5)
#define FIELD_JPEGPOINTTRANSFORM (FIELD_CODEC+6)
#define FIELD_JPEGQTABLES (FIELD_CODEC+7)
#define FIELD_JPEGDCTABLES (FIELD_CODEC+8)
#define FIELD_JPEGACTABLES (FIELD_CODEC+9)
#define FIELD_WANG_PAGECONTROL (FIELD_CODEC+10)
#define FIELD_JPEGCOLORMODE (FIELD_CODEC+11)

typedef struct jpeg_destination_mgr jpeg_destination_mgr;
typedef struct jpeg_source_mgr jpeg_source_mgr;
typedef struct jpeg_error_mgr jpeg_error_mgr;

/* State variable for each open TIFF file that uses "libjpeg" for JPEG
   decompression.  (Note:  This file should NEVER perform JPEG compression
   except in the manner implemented by the "tif_jpeg.c" file, elsewhere in this
   library; see comments above.)  JPEG Library internal state is recorded in a
   "jpeg_{de}compress_struct", while a "jpeg_common_struct" records a few items
   common to both compression and expansion.  The "cinfo" field containing JPEG
   Library state MUST be the 1st member of our own state variable, so that we
   can safely "cast" pointers back and forth.
*/
typedef struct             /* This module's private, per-image state variable */
  {
    union         /* JPEG Library state variable; this MUST be our 1st field! */
      {
     /* struct jpeg_compress_struct c; */
        struct jpeg_decompress_struct d;
        struct jpeg_common_struct comm;
      } cinfo;
    jpeg_error_mgr err;                         /* JPEG Library error manager */
    JMP_BUF exit_jmpbuf;             /* ...for catching JPEG Library failures */
#   ifdef never

 /* (The following two fields could be a "union", but they're small enough that
    it's not worth the effort.)
 */
    jpeg_destination_mgr dest;             /* Destination for compressed data */
#   endif
    jpeg_source_mgr src;                           /* Source of expanded data */
    JSAMPARRAY ds_buffer[MAX_COMPONENTS]; /* ->Temporary downsampling buffers */
    TIFF *tif;                        /* Reverse pointer, needed by some code */
    TIFFVGetMethod vgetparent;                    /* "Super class" methods... */
    TIFFVSetMethod vsetparent;
    TIFFStripMethod defsparent;
    TIFFTileMethod deftparent;
    void *jpegtables;           /* ->"New" JPEG tables, if we synthesized any */
    uint32 is_WANG,    /* <=> Microsoft Wang Imaging for Windows output file? */
           jpegtables_length;   /* Length of "new" JPEG tables, if they exist */
    tsize_t bytesperline;          /* No. of decompressed Bytes per scan line */
    int jpegquality,                             /* Compression quality level */
        jpegtablesmode,                          /* What to put in JPEGTables */
        samplesperclump,
        scancount;                           /* No. of scan lines accumulated */
    uint16 h_sampling,                          /* Luminance sampling factors */
           v_sampling,
           photometric;      /* Copy of "PhotometricInterpretation" tag value */
    u_char jpegcolormode;           /* Who performs RGB <-> YCbCr conversion? */
        /* JPEGCOLORMODE_RAW <=> TIFF Library does conversion */
        /* JPEGCOLORMODE_RGB <=> JPEG Library does conversion */
  } OJPEGState;
#define OJState(tif)((OJPEGState*)(tif)->tif_data)

static const TIFFFieldInfo ojpegFieldInfo[]=/* JPEG-specific TIFF-record tags */
  {

 /* This is the current JPEG-in-TIFF metadata-encapsulation tag, and its
    treatment in this file is idiosyncratic.  It should never appear in a
    "source" image conforming to the TIFF Version 6.0 specification, so we
    arrange to report an error if it appears.  But in order to support possible
    future conversion of "old" JPEG-in-TIFF encapsulations to "new" ones, we
    might wish to synthesize an equivalent value to be returned by the TIFF
    Library's "getfield" method.  So, this table tells the TIFF Library to pass
    these records to us in order to filter them below.
 */
    {
      TIFFTAG_JPEGTABLES            ,TIFF_VARIABLE,TIFF_VARIABLE,
      TIFF_UNDEFINED,FIELD_JPEGTABLES            ,FALSE,TRUE ,"JPEGTables"
    },

 /* These tags are defined by the TIFF Version 6.0 specification and are now
    obsolete.  This module reads them from an old "source" image, but it never
    writes them to a new "destination" image.
 */
    {
      TIFFTAG_JPEGPROC              ,1            ,1            ,
      TIFF_SHORT    ,FIELD_JPEGPROC              ,FALSE,FALSE,"JPEGProc"
    },
    {
      TIFFTAG_JPEGIFOFFSET          ,1            ,1            ,
      TIFF_LONG     ,FIELD_JPEGIFOFFSET          ,FALSE,FALSE,"JPEGInterchangeFormat"
    },
    {
      TIFFTAG_JPEGIFBYTECOUNT       ,1            ,1            ,
      TIFF_LONG     ,FIELD_JPEGIFBYTECOUNT       ,FALSE,FALSE,"JPEGInterchangeFormatLength"
    },
    {
      TIFFTAG_JPEGRESTARTINTERVAL   ,1            ,1            ,
      TIFF_SHORT    ,FIELD_JPEGRESTARTINTERVAL   ,FALSE,FALSE,"JPEGRestartInterval"
    },
    {
      TIFFTAG_JPEGLOSSLESSPREDICTORS,TIFF_VARIABLE,TIFF_VARIABLE,
      TIFF_SHORT    ,FIELD_JPEGLOSSLESSPREDICTORS,FALSE,TRUE ,"JPEGLosslessPredictors"
    },
    {
      TIFFTAG_JPEGPOINTTRANSFORM    ,TIFF_VARIABLE,TIFF_VARIABLE,
      TIFF_SHORT    ,FIELD_JPEGPOINTTRANSFORM    ,FALSE,TRUE ,"JPEGPointTransforms"
    },
    {
      TIFFTAG_JPEGQTABLES           ,TIFF_VARIABLE,TIFF_VARIABLE,
      TIFF_LONG     ,FIELD_JPEGQTABLES           ,FALSE,TRUE ,"JPEGQTables"
    },
    {
      TIFFTAG_JPEGDCTABLES          ,TIFF_VARIABLE,TIFF_VARIABLE,
      TIFF_LONG     ,FIELD_JPEGDCTABLES          ,FALSE,TRUE ,"JPEGDCTables"
    },
    {
      TIFFTAG_JPEGACTABLES          ,TIFF_VARIABLE,TIFF_VARIABLE,
      TIFF_LONG     ,FIELD_JPEGACTABLES          ,FALSE,TRUE ,"JPEGACTables"
    },
    {
      TIFFTAG_WANG_PAGECONTROL      ,TIFF_VARIABLE,1            ,
      TIFF_LONG     ,FIELD_WANG_PAGECONTROL      ,FALSE,FALSE,"WANG PageControl"
    },

 /* This is a pseudo tag intended for internal use only by the TIFF Library and
    its clients, which should never appear in an input/output image file.  It
    specifies whether the TIFF Library will perform YCbCr<->RGB color-space
    conversion (JPEGCOLORMODE_RAW <=> 0) or ask the JPEG Library to do it
    (JPEGCOLORMODE_RGB <=> 1).
 */
    {
      TIFFTAG_JPEGCOLORMODE         ,0            ,0            ,
      TIFF_ANY      ,FIELD_PSEUDO                ,FALSE,FALSE,"JPEGColorMode"
    }
  };
static const char JPEGLib_name[]={"JPEG Library"},
                  bad_bps[]={"%u BitsPerSample not allowed for JPEG"},
#                 ifdef never
                  no_write_frac[]={"fractional scan line discarded"},
#                 endif
                  no_read_frac[]={"fractional scan line not read"},
                  no_jtable_space[]={"No space for JPEGTables"};

/* The following diagnostic subroutines interface with and replace default
   subroutines in the JPEG Library.  Our basic strategy is to use "setjmp()"/
   "longjmp()" in order to return control to the TIFF Library when the JPEG
   library detects an error, and to use TIFF Library subroutines for displaying
   diagnostic messages to a client application.
*/
static void
TIFFojpeg_error_exit(register j_common_ptr cinfo)
  { char buffer[JMSG_LENGTH_MAX];

    (*cinfo->err->format_message)(cinfo,buffer);
    TIFFError(JPEGLib_name,buffer); /* Display error message */
    jpeg_abort(cinfo); /* Clean up JPEG Library state */
    LONGJMP(((OJPEGState *)cinfo)->exit_jmpbuf,1); /* Return to TIFF client */
  }

static void
TIFFojpeg_output_message(register j_common_ptr cinfo)
  { char buffer[JMSG_LENGTH_MAX];

 /* This subroutine is invoked only for warning messages, since the JPEG
    Library's "error_exit" method does its own thing and "trace_level" is never
    set > 0.
 */
    (*cinfo->err->format_message)(cinfo,buffer);
    TIFFWarning(JPEGLib_name,buffer);
  }

/* The following subroutines, which also interface with the JPEG Library, exist
   mainly in limit the side effects of "setjmp()" and convert JPEG normal/error
   conditions into TIFF Library return codes.
*/
#define CALLJPEG(sp,fail,op)(SETJMP((sp)->exit_jmpbuf)?(fail):(op))
#define CALLVJPEG(sp,op)CALLJPEG(sp,0,((op),1))
#ifdef never

static int
TIFFojpeg_create_compress(register OJPEGState *sp)
  {
    sp->cinfo.c.err = jpeg_std_error(&sp->err); /* Initialize error handling */
    sp->err.error_exit = TIFFojpeg_error_exit;
    sp->err.output_message = TIFFojpeg_output_message;
    return CALLVJPEG(sp,jpeg_create_compress(&sp->cinfo.c));
  }

static int
TIFFojpeg_finish_compress(register OJPEGState *sp)
  {return CALLVJPEG(sp,jpeg_finish_compress(&sp->cinfo.c));}

static int
TIFFojpeg_set_colorspace(register OJPEGState *sp,J_COLOR_SPACE colorspace)
  {return CALLVJPEG(sp,jpeg_set_colorspace(&sp->cinfo.c,colorspace));}

static int
TIFFojpeg_set_defaults(register OJPEGState *sp)
  {return CALLVJPEG(sp,jpeg_set_defaults(&sp->cinfo.c));}

static int
TIFFojpeg_set_quality(register OJPEGState *sp,int quality,boolean force_baseline)
  {return CALLVJPEG(sp,jpeg_set_quality(&sp->cinfo.c,quality,force_baseline));}

static int
TIFFojpeg_start_compress(register OJPEGState *sp,boolean write_all_tables)
  {return CALLVJPEG(sp,jpeg_start_compress(&sp->cinfo.c,write_all_tables));}

static int
TIFFojpeg_suppress_tables(register OJPEGState *sp,boolean suppress)
  {return CALLVJPEG(sp,jpeg_suppress_tables(&sp->cinfo.c,suppress));}

static int
TIFFojpeg_write_raw_data(register OJPEGState *sp,JSAMPIMAGE data,int num_lines)
  { return
      CALLJPEG(sp,-1,(int)jpeg_write_raw_data(&sp->cinfo.c,data,(JDIMENSION)num_lines));
  }

static int
TIFFojpeg_write_scanlines(register OJPEGState *sp,JSAMPARRAY scanlines,
                         int num_lines)
  { return
      CALLJPEG(sp,-1,(int)jpeg_write_scanlines(&sp->cinfo.c,scanlines,(JDIMENSION)num_lines));
  }

static int
TIFFojpeg_write_tables(register OJPEGState *sp)
  {return CALLVJPEG(sp,jpeg_write_tables(&sp->cinfo.c));}
#else /* well, hardly ever */

static int
_notSupported(register TIFF *tif)
  { const TIFFCodec *c = TIFFFindCODEC(tif->tif_dir.td_compression);

    TIFFError(tif->tif_name,"%s compression is not supported",c->name);
    return 0;
  }
#endif /* never */

static int
TIFFojpeg_abort(register OJPEGState *sp)
  {return CALLVJPEG(sp,jpeg_abort(&sp->cinfo.comm));}

static JSAMPARRAY
TIFFojpeg_alloc_sarray(register OJPEGState *sp,int pool_id,
                      JDIMENSION samplesperrow,JDIMENSION numrows)
  { return
      CALLJPEG(sp,0,(*sp->cinfo.comm.mem->alloc_sarray)(&sp->cinfo.comm,pool_id,samplesperrow, numrows));
  }

static int
TIFFojpeg_create_decompress(register OJPEGState *sp)
  {
    sp->cinfo.d.err = jpeg_std_error(&sp->err); /* Initialize error handling */
    sp->err.error_exit = TIFFojpeg_error_exit;
    sp->err.output_message = TIFFojpeg_output_message;
    return CALLVJPEG(sp,jpeg_create_decompress(&sp->cinfo.d));
  }

static int
TIFFojpeg_destroy(register OJPEGState *sp)
  {return CALLVJPEG(sp,jpeg_destroy(&sp->cinfo.comm));}

static int
TIFFojpeg_finish_decompress(register OJPEGState *sp)
  {return CALLJPEG(sp,-1,(int)jpeg_finish_decompress(&sp->cinfo.d));}

static int