This section of the archives stores flipcode's complete Developer Toolbox collection, featuring a variety of mini-articles and source code contributions from our readers.

| Jpeg Animstream Dumper Submitted by

I've been using this for quite some time, and people who went to S&V 2001 wanted the code... so I figured I might as well put it up here if not elsewhere. Basically, this is what I used to dump a stream of Jpeg's to disk. School machines didn't have VFW api headers, and obviously, undergrads don't have admin privileges to install anything... *sigh*... So I had to resort to this. Anyway, I used the Jpeg wrapper class that showed up in an older COTD (albeit before it actually showed up on COTD). I have a feeling that the code I grabbed was a little older than the code that the poster was actually using. It had this annoying memory leak that caused 2 copies of every compressed Jpeg image... Pretty harmless if you're just doing a snap or two, but it causes some nice overflow problems after dumping about 1300 frames at 85% quality... ^__^ So that was a simple fix to deal with... and I just wrote the following function. The other things you'll need to use it are included in the zip. Add this to your little demo. The main reason for using globals is just because of the fact that memory blocks would otherwise keep being allocated and deallocated as they fell out of scope. This way, at least, there's one and only one copy of the pixmaps and file pointer., and memory doesn't end up all fragmented.

    // Pixel Buffers...
    unsigned char *pPixelData = new unsigned char[640*480*3];
    unsigned char *pPixelData2 = new unsigned char[640*480*3];
    ofstream file;

    void SaveSnap(int num, int quality)
    {
    	char fname[32];
    	unsigned char *buff;
    	sprintf(fname, "render\\Anm%04d.jpg",num);

    	file.open(fname, ios::binary);

    	int nbytes = 640 * 480 * 3;

    	// Copy from OpenGL
    	// Don't forget to make OpenGL rendering context
    	// current (wglMakeCurrent)
    	glReadPixels(0, 0, 640, 480, GL_RGB, GL_UNSIGNED_BYTE, pPixelData);

    	// Flip the image because of GL's up = positive-y
    	for (int j=0; j < 480; j ++)    // line counter
    	{
    	   for (int i=0; i < 640;i++)  // column counter
    	   {
    	   	pPixelData2[(j*640+i)*3] = pPixelData[((479-j)*640+i)*3];
    		pPixelData2[(j*640+i)*3+1] = pPixelData[((479-j)*640+i)*3+1];
    		pPixelData2[(j*640+i)*3+2] = pPixelData[((479-j)*640+i)*3+2];
    	   }
    	}

    	// Compressing in jpeg
    	int len; // the length of the buffer after compression
    	buff = (unsigned char*)Jpeg::Compress(pPixelData2, 640, 480, 3, len, quality);

    	// Writing file and that's it
    	file.write(buff,len);
    	file.close();

    	delete buff;
    }

And at the end of your main loop (or at least in the function that repeatedly called in your main renderloop), you basically add something like this --

    	SaveSnap(frameno, 90);     // or whatever quality you want (percentage)
    	++frameno;

I also used routines in my demos that were frametime based, and for stream renderings, I hardcode a value for the frametimes so I can fake a constant framerate for animations. Anyway, if you want to see some results made with it --

> http://www.acm.uiuc.edu/siggraph/s&v/s&v2001.html

The piece by me is the only one that was actually realtime, so that's the only one that used this code. Granted, the stuff on the website are low-quality divx dumps and the sound on my animation is somehow 10 seconds out of sync (first few patterns getting cut off), but oh well...

Currently browsing [JpegDumper.zip] (72,443 bytes) - [ijl.h] - (47,440 bytes)

    /*M*
    //
    //
    //               INTEL CORPORATION PROPRIETARY INFORMATION
    //  This software is supplied under the terms of a license agreement or
    //  nondisclosure agreement with Intel Corporation and may not be copied
    //  or disclosed except in accordance with the terms of that agreement.
    //        Copyright (c) 1998 Intel Corporation. All Rights Reserved.
    //
    //
    //  File:
    //    ijl.h
    //
    //  Purpose:
    //    IJL Common Header File
    //    This file contains:  definitions for data types, data
    //    structures, error codes, and function prototypes used
    //    in the Intel(R) JPEG Library (IJL).
    //
    //  Version:
    //    1.0 beta 1
    //
    *M*/

    #ifndef __IJL_H__
    #define __IJL_H__

    #if defined( __cplusplus )
    extern "C" {
    #endif

    #ifndef IJL_ALL_WARNINGS

    #if _MSC_VER >= 1000

    /* nonstandard extension used : nameless struct/union          */
    #pragma warning(disable : 4201)
    /* nonstandard extension used : bit field types other than int */
    #pragma warning(disable : 4214)
    /* unreferenced inline function has been removed               */
    #pragma warning(disable : 4514)
    /* named type definition in parentheses                        */
    #pragma warning(disable : 4115)

    #endif /* _MSC_VER >= 1000 */

    #endif /* IJL_ALL_WARNINGS */

    #define _X86_
    #define WIN32_LEAN_AND_MEAN
    #include <windows.h>

    #ifdef _MSC_VER
    #  pragma pack (8)
    #endif

    /* /////////////////////////////////////////////////////////////////////////
    // Macros/Constants */

    #define IJL_NONE    0
    #define IJL_OTHER   255
    #define JBUFSIZE    4096    // Size of file I/O buffer (4K).

    #ifndef INT64
    #define INT64       __int64
    #endif
    #ifndef UINT64
    #define UINT64      unsigned INT64
    #endif

    #if defined( _IJL_STDIMP_ )

    #  define   IJLAPI(type,name,arg)  \
                  extern type WINAPI name arg

    #else

    #  if !defined( _IJL_API_ )

    #    define IJLAPI(type,name,arg)  \
                  extern __declspec(dllimport) type WINAPI name arg

    #  else

    #    define IJLAPI(type,name,arg)   \
                  extern __declspec(dllexport) type WINAPI name arg

    #  endif // _IJL_API_

    #endif //_IJL_STDIMP_

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        IJLibVersion
    //
    // Purpose:     Stores library version info.
    //
    // Context:
    //
    // Example:
    //   major           - 1
    //   minor           - 0
    //   build           - 1
    //   Name            - "ijl10.dll"
    //   Version         - "1.0.1 Beta1"
    //   InternalVersion - "1.0.1.1"
    //   BuildDate       - "Sep 22 1998"
    //   CallConv        - "DLL"
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct _IJLibVersion
    {
      int     major;
      int     minor;
      int     build;
      LPCTSTR Name;
      LPCTSTR Version;
      LPCTSTR InternalVersion;
      LPCTSTR BuildDate;
      LPCTSTR CallConv;

    } IJLibVersion;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        IJLIOTYPE
    //
    // Purpose:     Possible types of data read/write/other operations to be
    //              performed by the functions IJL_Read and IJL_Write.
    //
    //              See the Developer's Guide for details on appropriate usage.
    //
    // Fields:
    //
    //  IJL_JFILE_XXXXXXX   Indicates JPEG data in a stdio file.
    //
    //  IJL_JBUFF_XXXXXXX   Indicates JPEG data in an addressable buffer.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef enum
    {
      IJL_SETUP                   = -1,

      // Read JPEG parameters (i.e., height, width, channels,
      // sampling, etc.) from a JPEG bit stream.
      IJL_JFILE_READPARAMS        =  0,
      IJL_JBUFF_READPARAMS        =  1,

      // Read a JPEG Interchange Format image.
      IJL_JFILE_READWHOLEIMAGE    =  2,
      IJL_JBUFF_READWHOLEIMAGE    =  3,

      // Read JPEG tables from a JPEG Abbreviated Format bit stream.
      IJL_JFILE_READHEADER        =  4,
      IJL_JBUFF_READHEADER        =  5,

      // Read image info from a JPEG Abbreviated Format bit stream.
      IJL_JFILE_READENTROPY       =  6,
      IJL_JBUFF_READENTROPY       =  7,

      // Write an entire JFIF bit stream.
      IJL_JFILE_WRITEWHOLEIMAGE   =  8,
      IJL_JBUFF_WRITEWHOLEIMAGE   =  9,

      // Write a JPEG Abbreviated Format bit stream.
      IJL_JFILE_WRITEHEADER       = 10,
      IJL_JBUFF_WRITEHEADER       = 11,

      // Write image info to a JPEG Abbreviated Format bit stream.
      IJL_JFILE_WRITEENTROPY      = 12,
      IJL_JBUFF_WRITEENTROPY      = 13,

      // Scaled Decoding Options:

      // Reads a JPEG image scaled to 1/2 size.
      IJL_JFILE_READONEHALF       = 14,
      IJL_JBUFF_READONEHALF       = 15,

      // Reads a JPEG image scaled to 1/4 size.
      IJL_JFILE_READONEQUARTER    = 16,
      IJL_JBUFF_READONEQUARTER    = 17,

      // Reads a JPEG image scaled to 1/8 size.
      IJL_JFILE_READONEEIGHTH     = 18,
      IJL_JBUFF_READONEEIGHTH     = 19,

      // Reads an embedded thumbnail from a JFIF bit stream.
      IJL_JFILE_READTHUMBNAIL     = 20,
      IJL_JBUFF_READTHUMBNAIL     = 21

    } IJLIOTYPE;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        IJL_COLOR
    //
    // Purpose:     Possible color space formats.
    //
    //              Note these formats do *not* necessarily denote
    //              the number of channels in the color space.
    //              There exists separate "channel" fields in the
    //              JPEG_CORE_PROPERTIES data structure specifically
    //              for indicating the number of channels in the
    //              JPEG and/or DIB color spaces.
    //
    //              See the Developer's Guide for details on appropriate usage.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef enum
    {
      IJL_RGB         = 1,    // Red-Green-Blue color space.
      IJL_BGR         = 2,    // Reversed channel ordering from IJL_RGB.
      IJL_YCBCR       = 3,    // Luminance-Chrominance color space as defined
                              // by CCIR Recommendation 601.
      IJL_G           = 4,    // Grayscale color space.
      IJL_RGBA_FPX    = 5,    // FlashPix RGB 4 channel color space that
                              // has pre-multiplied opacity.
      IJL_YCBCRA_FPX  = 6     // FlashPix YCbCr 4 channel color space that
                              // has pre-multiplied opacity.

    //  IJL_OTHER             // Some other color space not defined by the IJL.
                              // (This means no color space conversion will
                              //  be done by the IJL.)

    } IJL_COLOR;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        IJL_JPGSUBSAMPLING
    //
    // Purpose:     Possible subsampling formats used in the JPEG.
    //
    //              See the Developer's Guide for details on appropriate usage.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef enum
    {
      IJL_411     = 1,    // Valid on a JPEG w/ 3 channels.
      IJL_422     = 2,    // Valid on a JPEG w/ 3 channels.

      IJL_4114    = 3,    // Valid on a JPEG w/ 4 channels.
      IJL_4224    = 4,    // Valid on a JPEG w/ 4 channels.

    //  IJL_NONE    = Corresponds to "No Subsampling".
    //                Valid on a JPEG w/ any number of channels.

    //  IJL_OTHER   = Valid entry, but only used internally to the IJL.

    } IJL_JPGSUBSAMPLING;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        IJL_DIBSUBSAMPLING
    //
    // Purpose:     Possible subsampling formats used in the DIB.
    //
    //              See the Developer's Guide for details on appropriate usage.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef enum
    {
    //  IJL_NONE    = Corresponds to "No Subsampling".

    } IJL_DIBSUBSAMPLING;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        HUFFMAN_TABLE
    //
    // Purpose:     Stores Huffman table information in a fast-to-use format.
    //
    // Context:     Used by Huffman encoder/decoder to access Huffman table
    //              data.  Raw Huffman tables are formatted to fit this
    //              structure prior to use.
    //
    // Fields:
    //  huff_class  0 == DC Huffman or lossless table, 1 == AC table.
    //  ident       Huffman table identifier, 0-3 valid (Extended Baseline).
    //  huffelem    Huffman elements for codes <= 8 bits long;
    //              contains both zero run-length and symbol length in bits.
    //  huffval     Huffman values for codes 9-16 bits in length.
    //  mincode     Smallest Huffman code of length n.
    //  maxcode     Largest Huffman code of length n.
    //  valptr      Starting index into huffval[] for symbols of length k.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct _HUFFMAN_TABLE
    {
      int             huff_class;
      int             ident;
      unsigned int    huffelem[256];
      unsigned short  huffval[256];
      unsigned short  mincode[17];
      unsigned short  maxcode[18];
      unsigned short  valptr[17];

    } HUFFMAN_TABLE;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        JPEGHuffTable
    //
    // Purpose:     Stores pointers to JPEG-binary spec compliant
    //              Huffman table information.
    //
    // Context:     Used by interface and table methods to specify encoder
    //              tables to generate and store JPEG images.
    //
    // Fields:
    //  bits        Points to number of codes of length i (<=16 supported).
    //  vals        Value associated with each Huffman code.
    //  hclass      0 == DC table, 1 == AC table.
    //  ident       Specifies the identifier for this table.
    //              0-3 for extended JPEG compliance.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct
    {
      unsigned char*  bits;
      unsigned char*  vals;
      unsigned char   hclass;
      unsigned char   ident;

    } JPEGHuffTable;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        QUANT_TABLE
    //
    // Purpose:     Stores quantization table information in a
    //              fast-to-use format.
    //
    // Context:     Used by quantizer/dequantizer to store formatted
    //              quantization tables.
    //
    // Fields:
    //  precision   0 => elements contains 8-bit elements,
    //              1 => elements contains 16-bit elements.
    //  ident       Table identifier (0-3).
    //  elements    Pointer to 64 table elements + 16 extra elements to catch
    //              input data errors that may cause malfunction of the
    //              Huffman decoder.
    //  elarray     Space for elements (see above) plus 8 bytes to align
    //              to a quadword boundary.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct _QUANT_TABLE
    {
      int     precision;
      int     ident;
      short*  elements;
      short   elarray [84];

    } QUANT_TABLE;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        JPEGQuantTable
    //
    // Purpose:     Stores pointers to JPEG binary spec compliant
    //              quantization table information.
    //
    // Context:     Used by interface and table methods to specify encoder
    //              tables to generate and store JPEG images.
    //
    // Fields:
    //  quantizer   Zig-zag order elements specifying quantization factors.
    //  ident       Specifies identifier for this table.
    //              0-3 valid for Extended Baseline JPEG compliance.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct
    {
      unsigned char* quantizer;
      unsigned char  ident;

    } JPEGQuantTable;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        FRAME_COMPONENT
    //
    // Purpose:     One frame-component structure is allocated per component
    //              in a frame.
    //
    // Context:     Used by Huffman decoder to manage components.
    //
    // Fields:
    //  ident       Component identifier.  The tables use this ident to
    //              determine the correct table for each component.
    //  hsampling   Horizontal subsampling factor for this component,
    //              1-4 are legal.
    //  vsampling   Vertical subsampling factor for this component,
    //              1-4 are legal.
    //  quant_sel   Quantization table selector.  The quantization table
    //              used by this component is determined via this selector.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct _FRAME_COMPONENT
    {
      int ident;
      int hsampling;
      int vsampling;
      int quant_sel;

    } FRAME_COMPONENT;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        FRAME
    //
    // Purpose:     Stores frame-specific data.
    //
    // Context:     One Frame structure per image.
    //
    // Fields:
    //  precision       Sample precision in bits.
    //  width           Width of the source image in pixels.
    //  height          Height of the source image in pixels.
    //  MCUheight       Height of a frame MCU.
    //  MCUwidth        Width of a frame MCU.
    //  max_hsampling   Max horiz sampling ratio of any component in the frame.
    //  max_vsampling   Max vert sampling ratio of any component in the frame.
    //  ncomps          Number of components/channels in the frame.
    //  horMCU          Number of horizontal MCUs in the frame.
    //  totalMCU        Total number of MCUs in the frame.
    //  comps           Array of 'ncomps' component descriptors.
    //  restart_interv  Indicates number of MCUs after which to restart the
    //                  entropy parameters.
    //  SeenAllDCScans  Used when decoding Multiscan images to determine if
    //                  all channels of an image have been decoded.
    //  SeenAllACScans  (See SeenAllDCScans)
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct _FRAME
    {
      int              precision;
      int              width;
      int              height;
      int              MCUheight;
      int              MCUwidth;
      int              max_hsampling;
      int              max_vsampling;
      int              ncomps;
      int              horMCU;
      long             totalMCU;
      FRAME_COMPONENT* comps;
      int              restart_interv;
      int              SeenAllDCScans;
      int              SeenAllACScans;

    } FRAME;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        SCAN_COMPONENT
    //
    // Purpose:     One scan-component structure is allocated per component
    //              of each scan in a frame.
    //
    // Context:     Used by Huffman decoder to manage components within scans.
    //
    // Fields:
    //  comp        Component number, index to the comps member of FRAME.
    //  hsampling   Horizontal sampling factor.
    //  vsampling   Vertical sampling factor.
    //  dc_table    DC Huffman table pointer for this scan.
    //  ac_table    AC Huffman table pointer for this scan.
    //  quant_table Quantization table pointer for this scan.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct
    {
      int            comp;
      int            hsampling;
      int            vsampling;
      HUFFMAN_TABLE* dc_table;
      HUFFMAN_TABLE* ac_table;
      QUANT_TABLE*   quant_table;

    } SCAN_COMPONENT;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        SCAN
    //
    // Purpose:     One SCAN structure is allocated per scan in a frame.
    //
    // Context:     Used by Huffman decoder to manage scans.
    //
    // Fields:
    //  ncomps          Number of image components in a scan, 1-4 legal.
    //  gray_scale      If TRUE, decode only the Y channel.
    //  start_spec      Start coefficient of spectral or predictor selector.
    //  end_spec        End coefficient of spectral selector.
    //  approx_high     High bit position in successive approximation
    //                  Progressive coding.
    //  approx_low      Low bit position in successive approximation
    //                  Progressive coding.
    //  restart_interv  Restart interval, 0 if disabled.
    //  curxMCU         Next horizontal MCU index to be processed after
    //                  an interrupted SCAN.
    //  curyMCU         Next vertical MCU index to be processed after
    //                  an interrupted SCAN.
    //  dc_diff         Array of DC predictor values for DPCM modes.
    //  comps           Array of ncomps SCAN_COMPONENT component identifiers.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct _SCAN
    {
      int             ncomps;
      int             gray_scale;
      int             start_spec;
      int             end_spec;
      int             approx_high;
      int             approx_low;
      UINT            restart_interv;
      DWORD           curxMCU;
      DWORD           curyMCU;
      int             dc_diff[4];
      SCAN_COMPONENT* comps;

    } SCAN;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        DCTTYPE
    //
    // Purpose:     Possible algorithms to be used to perform the discrete
    //              cosine transform (DCT).
    //
    // Fields:
    //  IJL_AAN     The AAN (Arai, Agui, and Nakajima) algorithm from
    //              Trans. IEICE, vol. E 71(11), 1095-1097, Nov. 1988.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef enum
    {
      IJL_AAN = 0

    } DCTTYPE;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        PROCESSOR_TYPE
    //
    // Purpose:     Possible types of processors.
    //              Note that the enums are defined in ascending order
    //              depending upon their various IA32 instruction support.
    //
    // Fields:
    //
    // IJL_OTHER_PROC
    //      Does not support the CPUID instruction and
    //      assumes no Pentium(R) processor instructions.
    //
    // IJL_PENTIUM_PROC
    //      Corresponds to an Intel(R) Pentium(R) processor
    //      (or a 100% compatible) that supports the
    //      Pentium(R) processor instructions.
    //
    // IJL_PENTIUM_PRO_PROC
    //      Corresponds to an Intel(R) Pentium(R) Pro processor
    //      (or a 100% compatible) that supports the
    //      Pentium(R) Pro processor instructions.
    //
    // IJL_PENTIUM_PROC_MMX_TECH
    //      Corresponds to an Intel(R) Pentium(R) processor
    //      with MMX(TM) technology (or a 100% compatible)
    //      that supports the MMX(TM) instructions.
    //
    // IJL_PENTIUM_II_PROC
    //      Corresponds to an Intel(R) Pentium(R) II processor
    //      (or a 100% compatible) that supports both the
    //      Pentium(R) Pro processor instructions and the
    //      MMX(TM) instructions.
    //
    //  Any additional processor types that support a superset
    //  of both the Pentium(R) Pro processor instructions and the
    //  MMX(TM) instructions should be given an enum value greater
    //  than IJL_PENTIUM_II_PROC.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef enum
    {
      IJL_OTHER_PROC              = 0,
      IJL_PENTIUM_PROC            = 1,
      IJL_PENTIUM_PRO_PROC        = 2,
      IJL_PENTIUM_PROC_MMX_TECH   = 3,
      IJL_PENTIUM_II_PROC         = 4

    } PROCESSOR_TYPE;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        ENTROPYSTRUCT
    //
    // Purpose:     Stores the decoder state information necessary to "jump"
    //              to a particular MCU row in a compressed entropy stream.
    //
    // Context:     Used to persist the decoder state within Decode_Scan when
    //              decoding using ROIs.
    //
    // Fields:
    //      offset              Offset (in bytes) into the entropy stream
    //                          from the beginning.
    //      dcval1              DC val at the beginning of the MCU row
    //                          for component 1.
    //      dcval2              DC val at the beginning of the MCU row
    //                          for component 2.
    //      dcval3              DC val at the beginning of the MCU row
    //                          for component 3.
    //      dcval4              DC val at the beginning of the MCU row
    //                          for component 4.
    //      bit_buffer_64       64-bit Huffman bit buffer.  Stores current
    //                          bit buffer at the start of a MCU row.
    //                          Also used as a 32-bit buffer on 32-bit
    //                          architectures.
    //      bitbuf_bits_valid   Number of valid bits in the above bit buffer.
    //      unread_marker       Have any markers been decoded but not
    //                          processed at the beginning of a MCU row?
    //                          This entry holds the unprocessed marker, or
    //                          0 if none.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct
    {
      DWORD   offset;
      int     dcval1;
      int     dcval2;
      int     dcval3;
      int     dcval4;
      UINT64  bit_buffer_64;
      int     bitbuf_bits_valid;
      BYTE    unread_marker;

    } ENTROPYSTRUCT;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        STATE
    //
    // Purpose:     Stores the active state of the IJL.
    //
    // Context:     Used by all low-level routines to store pseudo-global or
    //              state variables.
    //
    // Fields:
    //      bit_buffer_64           64-bit bitbuffer utilized by Huffman
    //                              encoder/decoder algorithms utilizing routines
    //                              designed for MMX(TM) technology.
    //      bit_buffer_32           32-bit bitbuffer for all other Huffman
    //                              encoder/decoder algorithms.
    //      bitbuf_bits_valid       Number of bits in the above two fields that
    //                              are valid.
    //
    //      cur_entropy_ptr         Current position (absolute address) in
    //                              the entropy buffer.
    //      start_entropy_ptr       Starting position (absolute address) of
    //                              the entropy buffer.
    //      end_entropy_ptr         Ending position (absolute address) of
    //                              the entropy buffer.
    //      entropy_bytes_processed Number of bytes actually processed
    //                              (passed over) in the entropy buffer.
    //      entropy_buf_maxsize     Max size of the entropy buffer.
    //      entropy_bytes_left      Number of bytes left in the entropy buffer.
    //      Prog_EndOfBlock_Run     Progressive block run counter.
    //
    //      DIB_ptr                 Temporary offset into the input/output DIB.
    //
    //      unread_marker           If a marker has been read but not processed,
    //                              stick it in this field.
    //      processor_type          (0, 1, or 2) == current processor does not
    //                              support MMX(TM) instructions.
    //                              (3 or 4) == current processor does
    //                              support MMX(TM) instructions.
    //      cur_scan_comp           On which component of the scan are we working?
    //      file                    Process file handle, or
    //                              0x00000000 if no file is defined.
    //      JPGBuffer               Entropy buffer (~4K).
    //
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct _STATE
    {
      // Bit buffer.
      UINT64          bit_buffer_64;
      DWORD           bit_buffer_32;
      int             bitbuf_bits_valid;

      // Entropy.
      BYTE*           cur_entropy_ptr;
      BYTE*           start_entropy_ptr;
      BYTE*           end_entropy_ptr;
      long            entropy_bytes_processed;
      long            entropy_buf_maxsize;
      int             entropy_bytes_left;
      int             Prog_EndOfBlock_Run;

      // Input or output DIB.
      BYTE*           DIB_ptr;

      // Control.
      BYTE            unread_marker;
      PROCESSOR_TYPE  processor_type;
      int             cur_scan_comp;
      HANDLE          file;
      BYTE            JPGBuffer [JBUFSIZE];

    } STATE;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        FAST_MCU_PROCESSING_TYPE
    //
    // Purpose:     Advanced Control Option.  Do NOT modify.
    //              WARNING:  Used for internal reference only.
    //
    // Fields:
    //
    //   IJL_(sampling)_(JPEG color space)_(sampling)_(DIB color space)
    //      Decode is read left to right w/ upsampling.
    //      Encode is read right to left w/ subsampling.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef enum
    {
      IJL_NO_CC_OR_US                     = 0,

      IJL_111_YCBCR_111_RGB               = 1,
      IJL_111_YCBCR_111_BGR               = 2,

      IJL_411_YCBCR_111_RGB               = 3,
      IJL_411_YCBCR_111_BGR               = 4,

      IJL_422_YCBCR_111_RGB               = 5,
      IJL_422_YCBCR_111_BGR               = 6,

      IJL_111_YCBCR_1111_RGBA_FPX         = 7,
      IJL_411_YCBCR_1111_RGBA_FPX         = 8,
      IJL_422_YCBCR_1111_RGBA_FPX         = 9,

      IJL_1111_YCBCRA_FPX_1111_RGBA_FPX   = 10,
      IJL_4114_YCBCRA_FPX_1111_RGBA_FPX   = 11,
      IJL_4224_YCBCRA_FPX_1111_RGBA_FPX   = 12,

      IJL_111_RGB_1111_RGBA_FPX           = 13,

      IJL_1111_RGBA_FPX_1111_RGBA_FPX     = 14

    } FAST_MCU_PROCESSING_TYPE;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        JPEG_PROPERTIES
    //
    // Purpose:     Stores low-level and control information.  It is used by
    //              both the encoder and decoder.  An advanced external user
    //              may access this structure to expand the interface
    //              capability.
    //
    //              See the Developer's Guide for an expanded description
    //              of this structure and its use.
    //
    // Context:     Used by all interface methods and most IJL routines.
    //
    // Fields:
    //
    //  iotype              IN:     Specifies type of data operation
    //                              (read/write/other) to be
    //                              performed by IJL_Read or IJL_Write.
    //  roi                 IN:     Rectangle-Of-Interest to read from, or
    //                              write to, in pixels.
    //  dcttype             IN:     DCT alogrithm to be used.
    //  fast_processing     OUT:    Supported fast pre/post-processing path.
    //                              This is set by the IJL.
    //  interrupt           IN:     Signals an interrupt has been requested.
    //
    //  DIBBytes            IN:     Pointer to buffer of uncompressed data.
    //  DIBWidth            IN:     Width of uncompressed data.
    //  DIBHeight           IN:     Height of uncompressed data.
    //  DIBPadBytes         IN:     Padding (in bytes) at end of each
    //                              row in the uncompressed data.
    //  DIBChannels         IN:     Number of components in the
    //                              uncompressed data.
    //  DIBColor            IN:     Color space of uncompressed data.
    //  DIBSubsampling      IN:     Required to be IJL_NONE.
    //  DIBLineBytes        OUT:    Number of bytes in an output DIB line
    //                              including padding.
    //
    //  JPGFile             IN:     Pointer to file based JPEG.
    //  JPGBytes            IN:     Pointer to buffer based JPEG.
    //  JPGSizeBytes        IN:     Max buffer size. Used with JPGBytes.
    //                      OUT:    Number of compressed bytes written.
    //  JPGWidth            IN:     Width of JPEG image.
    //                      OUT:    After reading (except READHEADER).
    //  JPGHeight           IN:     Height of JPEG image.
    //                      OUT:    After reading (except READHEADER).
    //  JPGChannels         IN:     Number of components in JPEG image.
    //                      OUT:    After reading (except READHEADER).
    //  JPGColor            IN:     Color space of JPEG image.
    //  JPGSubsampling      IN:     Subsampling of JPEG image.
    //                      OUT:    After reading (except READHEADER).
    //  JPGThumbWidth       OUT:    JFIF embedded thumbnail width [0-255].
    //  JPGThumbHeight      OUT:    JFIF embedded thumbnail height [0-255].
    //
    //  cconversion_reqd    OUT:    If color conversion done on decode, TRUE.
    //  upsampling_reqd     OUT:    If upsampling done on decode, TRUE.
    //  jquality            IN:     [0-100] where highest quality is 100.
    //  jinterleaveType     IN/OUT: 0 => MCU interleaved file, and
    //                              1 => 1 scan per component.
    //  numxMCUs            OUT:    Number of MCUs in the x direction.
    //  numyMCUs            OUT:    Number of MCUs in the y direction.
    //
    //  nqtables            IN/OUT: Number of quantization tables.
    //  maxquantindex       IN/OUT: Maximum index of quantization tables.
    //  nhuffActables       IN/OUT: Number of AC Huffman tables.
    //  nhuffDctables       IN/OUT: Number of DC Huffman tables.
    //  maxhuffindex        IN/OUT: Maximum index of Huffman tables.
    //  jFmtQuant           IN/OUT: Formatted quantization table info.
    //  jFmtAcHuffman       IN/OUT: Formatted AC Huffman table info.
    //  jFmtDcHuffman       IN/OUT: Formatted DC Huffman table info.
    //
    //  jEncFmtQuant        IN/OUT: Pointer to one of the above, or
    //                              to externally persisted table.
    //  jEncFmtAcHuffman    IN/OUT: Pointer to one of the above, or
    //                              to externally persisted table.
    //  jEncFmtDcHuffman    IN/OUT: Pointer to one of the above, or
    //                              to externally persisted table.
    //
    //  use_default_qtables IN:     Set to default quantization tables.
    //                              Clear to supply your own.
    //  use_default_htables IN:     Set to default Huffman tables.
    //                              Clear to supply your own.
    //  rawquanttables      IN:     Up to 4 sets of quantization tables.
    //  rawhufftables       IN:     Alternating pairs (DC/AC) of up to 4
    //                              sets of raw Huffman tables.
    //  HuffIdentifierAC    IN:     Indicates what channel the user-
    //                              supplied Huffman AC tables apply to.
    //  HuffIdentifierDC    IN:     Indicates what channel the user-
    //                              supplied Huffman DC tables apply to.
    //
    //  jframe              OUT:    Structure with frame-specific info.
    //  needframe           OUT:    TRUE when a frame has been detected.
    //
    //  jscan               Persistence for current scan pointer when
    //                      interrupted.
    //
    //  state               OUT:    Contains info on the state of the IJL.
    //  SawAdobeMarker      OUT:    Decoder saw an APP14 marker somewhere.
    //  AdobeXform          OUT:    If SawAdobeMarker TRUE, this indicates
    //                              the JPEG color space given by that marker.
    //
    //  rowoffsets          Persistence for the decoder MCU row origins
    //                      when decoding by ROI.  Offsets (in bytes
    //                      from the beginning of the entropy data)
    //                      to the start of each of the decoded rows.
    //                      Fill the offsets with -1 if they have not
    //                      been initalized and NULL could be the
    //                      offset to the first row.
    //
    //  MCUBuf              OUT:    Quadword aligned internal buffer.
    //                              Big enough for the largest MCU
    //                              (10 blocks) with extra room for
    //                              additional operations.
    //  tMCUBuf             OUT:    Version of above, without alignment.
    //
    //  processor_type      OUT:    Determines type of processor found
    //                              during initialization.
    //
    //  ignoreDCTs          IN:     Assert to bypass DCTs when processing
    //                              data.  Required for conformance
    //                              testing.
    //
    //  progressive_found   OUT:    1 when progressive image detected.
    //  coef_buffer         IN:     Pointer to a larger buffer containing
    //                              frequency coefficients when they
    //                              cannot be decoded dynamically
    //                              (i.e., as in progressive decoding).
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct
    {
      // Compression/Decompression control.
      IJLIOTYPE                iotype;               // default = IJL_SETUP
      RECT                     roi;                  // default = 0
      DCTTYPE                  dcttype;              // default = IJL_AAN
      FAST_MCU_PROCESSING_TYPE fast_processing;      // default = IJL_NO_CC_OR_US
      DWORD                    interrupt;            // default = FALSE

      // DIB specific I/O data specifiers.
      BYTE*                    DIBBytes;             // default = NULL
      DWORD                    DIBWidth;             // default = 0
      int                      DIBHeight;            // default = 0
      DWORD                    DIBPadBytes;          // default = 0
      DWORD                    DIBChannels;          // default = 3
      IJL_COLOR                DIBColor;             // default = IJL_BGR
      IJL_DIBSUBSAMPLING       DIBSubsampling;       // default = IJL_NONE
      int                      DIBLineBytes;         // default = 0

      // JPEG specific I/O data specifiers.
      LPTSTR                   JPGFile;              // default = NULL
      BYTE*                    JPGBytes;             // default = NULL
      DWORD                    JPGSizeBytes;         // default = 0
      DWORD                    JPGWidth;             // default = 0
      DWORD                    JPGHeight;            // default = 0
      DWORD                    JPGChannels;          // default = 3
      IJL_COLOR                JPGColor;             // default = IJL_YCBCR
      IJL_JPGSUBSAMPLING       JPGSubsampling;       // default = IJL_411
      DWORD                    JPGThumbWidth;        // default = 0
      DWORD                    JPGThumbHeight;       // default = 0

      // JPEG conversion properties.
      DWORD                    cconversion_reqd;     // default = TRUE
      DWORD                    upsampling_reqd;      // default = TRUE
      DWORD                    jquality;             // default = 75
      DWORD                    jinterleaveType;      // default = 0
      DWORD                    numxMCUs;             // default = 0
      DWORD                    numyMCUs;             // default = 0

      // Tables.
      DWORD                    nqtables;
      DWORD                    maxquantindex;
      DWORD                    nhuffActables;
      DWORD                    nhuffDctables;
      DWORD                    maxhuffindex;

      QUANT_TABLE              jFmtQuant[4];
      HUFFMAN_TABLE            jFmtAcHuffman[4];
      HUFFMAN_TABLE            jFmtDcHuffman[4];

      short*                   jEncFmtQuant[4];
      HUFFMAN_TABLE*           jEncFmtAcHuffman[4];
      HUFFMAN_TABLE*           jEncFmtDcHuffman[4];

      // Allow user-defined tables.
      DWORD                    use_default_qtables;
      DWORD                    use_default_htables;

      JPEGQuantTable           rawquanttables[4];
      JPEGHuffTable            rawhufftables[8];
      BYTE                     HuffIdentifierAC[4];
      BYTE                     HuffIdentifierDC[4];

      // Frame specific members.
      FRAME                    jframe;
      int                      needframe;

      // SCAN persistent members.
      SCAN*                    jscan;

      // State members.
      STATE                    state;
      DWORD                    SawAdobeMarker;
      DWORD                    AdobeXform;

      // ROI decoder members.
      ENTROPYSTRUCT*           rowoffsets;

      // Intermediate buffers.
      BYTE*                    MCUBuf;
      BYTE                     tMCUBuf[720*2];       // ???

      // Processor detected.
      PROCESSOR_TYPE           processor_type;

      // Test specific members.
      DWORD                    ignoreDCTs;

      // Progressive mode members.
      int                      progressive_found;
      short*                   coef_buffer;

    } JPEG_PROPERTIES;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        JPEG_CORE_PROPERTIES
    //
    // Purpose:     This is the primary data structure between the IJL and
    //              the external user.  It stores JPEG state information
    //              and controls the IJL.  It is user-modifiable.
    //
    //              See the Developer's Guide for details on appropriate usage.
    //
    // Context:     Used by all low-level IJL routines to store
    //              pseudo-global information.
    //
    // Fields:
    //
    //  UseJPEGPROPERTIES   Set this flag != 0 if you wish to override
    //                      the JPEG_CORE_PROPERTIES "IN" parameters with
    //                      the JPEG_PROPERTIES parameters.
    //
    //  DIBBytes            IN:     Pointer to buffer of uncompressed data.
    //  DIBWidth            IN:     Width of uncompressed data.
    //  DIBHeight           IN:     Height of uncompressed data.
    //  DIBPadBytes         IN:     Padding (in bytes) at end of each
    //                              row in the uncompressed data.
    //  DIBChannels         IN:     Number of components in the
    //                              uncompressed data.
    //  DIBColor            IN:     Color space of uncompressed data.
    //  DIBSubsampling      IN:     Required to be IJL_NONE.
    //
    //  JPGFile             IN:     Pointer to file based JPEG.
    //  JPGBytes            IN:     Pointer to buffer based JPEG.
    //  JPGSizeBytes        IN:     Max buffer size. Used with JPGBytes.
    //                      OUT:    Number of compressed bytes written.
    //  JPGWidth            IN:     Width of JPEG image.
    //                      OUT:    After reading (except READHEADER).
    //  JPGHeight           IN:     Height of JPEG image.
    //                      OUT:    After reading (except READHEADER).
    //  JPGChannels         IN:     Number of components in JPEG image.
    //                      OUT:    After reading (except READHEADER).
    //  JPGColor            IN:     Color space of JPEG image.
    //  JPGSubsampling      IN:     Subsampling of JPEG image.
    //                      OUT:    After reading (except READHEADER).
    //  JPGThumbWidth       OUT:    JFIF embedded thumbnail width [0-255].
    //  JPGThumbHeight      OUT:    JFIF embedded thumbnail height [0-255].
    //
    //  cconversion_reqd    OUT:    If color conversion done on decode, TRUE.
    //  upsampling_reqd     OUT:    If upsampling done on decode, TRUE.
    //  jquality            IN:     [0-100] where highest quality is 100.
    //
    //  jprops              "Low-Level" IJL data structure.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef struct _JPEG_CORE_PROPERTIES
    {
      DWORD   UseJPEGPROPERTIES;                     // default = 0

      // DIB specific I/O data specifiers.
      BYTE*               DIBBytes;                  // default = NULL
      DWORD               DIBWidth;                  // default = 0
      int                 DIBHeight;                 // default = 0
      DWORD               DIBPadBytes;               // default = 0
      DWORD               DIBChannels;               // default = 3
      IJL_COLOR           DIBColor;                  // default = IJL_BGR
      IJL_DIBSUBSAMPLING  DIBSubsampling;            // default = IJL_NONE

      // JPEG specific I/O data specifiers.
      LPTSTR              JPGFile;                   // default = NULL
      BYTE*               JPGBytes;                  // default = NULL
      DWORD               JPGSizeBytes;              // default = 0
      DWORD               JPGWidth;                  // default = 0
      DWORD               JPGHeight;                 // default = 0
      DWORD               JPGChannels;               // default = 3
      IJL_COLOR           JPGColor;                  // default = IJL_YCBCR
      IJL_JPGSUBSAMPLING  JPGSubsampling;            // default = IJL_411
      DWORD               JPGThumbWidth;             // default = 0
      DWORD               JPGThumbHeight;            // default = 0

      // JPEG conversion properties.
      DWORD               cconversion_reqd;          // default = TRUE
      DWORD               upsampling_reqd;           // default = TRUE
      DWORD               jquality;                  // default = 75

      // Low-level properties.
      JPEG_PROPERTIES     jprops;

    } JPEG_CORE_PROPERTIES;

    /*D*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        IJLERR
    //
    // Purpose:     Listing of possible "error" codes returned by the IJL.
    //
    //              See the Developer's Guide for details on appropriate usage.
    //
    // Context:     Used for error checking.
    //
    ////////////////////////////////////////////////////////////////////////////
    *D*/

    typedef enum
    {
      // The following "error" values indicate an "OK" condition.
      IJL_OK                          = 0,
      IJL_INTERRUPT_OK                = 1,
      IJL_ROI_OK                      = 2,

      // The following "error" values indicate an error has occurred.
      IJL_EXCEPTION_DETECTED          =  -1,
      IJL_INVALID_ENCODER             =  -2,
      IJL_UNSUPPORTED_SUBSAMPLING     =  -3,
      IJL_UNSUPPORTED_BYTES_PER_PIXEL =  -4,
      IJL_MEMORY_ERROR                =  -5,
      IJL_BAD_HUFFMAN_TABLE           =  -6,
      IJL_BAD_QUANT_TABLE             =  -7,
      IJL_INVALID_JPEG_PROPERTIES     =  -8,
      IJL_ERR_FILECLOSE               =  -9,
      IJL_INVALID_FILENAME            = -10,
      IJL_ERROR_EOF                   = -11,
      IJL_PROG_NOT_SUPPORTED          = -12,
      IJL_ERR_NOT_JPEG                = -13,
      IJL_ERR_COMP                    = -14,
      IJL_ERR_SOF                     = -15,
      IJL_ERR_DNL                     = -16,
      IJL_ERR_NO_HUF                  = -17,
      IJL_ERR_NO_QUAN                 = -18,
      IJL_ERR_NO_FRAME                = -19,
      IJL_ERR_MULT_FRAME              = -20,
      IJL_ERR_DATA                    = -21,
      IJL_ERR_NO_IMAGE                = -22,
      IJL_FILE_ERROR                  = -23,
      IJL_INTERNAL_ERROR              = -24,
      IJL_BAD_RST_MARKER              = -25,
      IJL_THUMBNAIL_DIB_TOO_SMALL     = -26,
      IJL_THUMBNAIL_DIB_WRONG_COLOR   = -27,
      IJL_RESERVED                    = -99

    } IJLERR;

    /* /////////////////////////////////////////////////////////////////////////
    //                     Function Prototypes (API Calls)                    //
    ///////////////////////////////////////////////////////////////////////// */

    /*F*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        ijlInit
    //
    // Purpose:     Used to initalize the IJL.
    //
    //              See the Developer's Guide for details on appropriate usage.
    //
    // Context:     Always call this before anything else.
    //              Also, only call this with a new jcprops structure, or
    //              after calling IJL_Free.  Otherwise, dynamically
    //              allocated memory may be leaked.
    //
    // Returns:     Any IJLERR value.  IJL_OK indicates success.
    //
    // Parameters:
    //  jcprops     Pointer to an externally allocated
    //              JPEG_CORE_PROPERTIES structure.
    //
    ////////////////////////////////////////////////////////////////////////////
    *F*/

    IJLAPI(IJLERR, ijlInit, ( JPEG_CORE_PROPERTIES* jcprops ));

    /*F*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        ijlFree
    //
    // Purpose:     Used to properly close down the IJL.
    //
    //              See the Developer's Guide for details on appropriate usage.
    //
    // Context:     Always call this when done using the IJL to perform
    //              clean-up of dynamically allocated memory.
    //              Note, IJL_Init will have to be called to use the
    //              IJL again.
    //
    // Returns:     Any IJLERR value.  IJL_OK indicates success.
    //
    // Parameters:
    //  jcprops     Pointer to an externally allocated
    //              JPEG_CORE_PROPERTIES structure.
    //
    ////////////////////////////////////////////////////////////////////////////
    *F*/

    IJLAPI(IJLERR, ijlFree, ( JPEG_CORE_PROPERTIES* jcprops ));

    /*F*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        IJL_Read
    //
    // Purpose:     Used to read JPEG data (entropy, or header, or both) into
    //              a user-supplied buffer (to hold the image data) and/or
    //              into the JPEG_CORE_PROPERTIES structure (to hold the
    //              header info).
    //
    // Context:     See the Developer's Guide for a detailed description
    //              on the use of this function.  The jcprops main data
    //              members are checked for consistency.
    //
    // Returns:     Any IJLERR value.  IJL_OK indicates success.
    //
    // Parameters:
    //  jcprops     Pointer to an externally allocated
    //              JPEG_CORE_PROPERTIES structure.
    //  iotype      Specifies what type of read operation to perform.
    //
    ////////////////////////////////////////////////////////////////////////////
    *F*/

    IJLAPI(IJLERR, ijlRead, ( JPEG_CORE_PROPERTIES* jcprops, IJLIOTYPE iotype ));

    /*F*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        ijlWrite
    //
    // Purpose:     Used to write JPEG data (entropy, or header, or both) into
    //              a user-supplied buffer (to hold the image data) and/or
    //              into the JPEG_CORE_PROPERTIES structure (to hold the
    //              header info).
    //
    // Context:     See the Developer's Guide for a detailed description
    //              on the use of this function.  The jcprops main data
    //              members are checked for consistency.
    //
    // Returns:     Any IJLERR value.  IJL_OK indicates success.
    //
    // Parameters:
    //  jcprops     Pointer to an externally allocated
    //              JPEG_CORE_PROPERTIES structure.
    //  iotype      Specifies what type of write operation to perform.
    //
    ////////////////////////////////////////////////////////////////////////////
    *F*/

    IJLAPI(IJLERR, ijlWrite, ( JPEG_CORE_PROPERTIES* jcprops, IJLIOTYPE iotype ));

    /*F*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        ijlGetLibVersion
    //
    // Purpose:     To identify the version number of the IJL.
    //
    // Context:     Call to get the IJL version number.
    //
    // Returns:     pointer to IJLibVersion struct
    //
    // Parameters:  none
    //
    ////////////////////////////////////////////////////////////////////////////
    *F*/

    IJLAPI(const IJLibVersion*, ijlGetLibVersion, (void));

    /*F*
    ////////////////////////////////////////////////////////////////////////////
    // Name:        ijlErrorStr
    //
    // Purpose:     Gets the string to describe error code.
    //
    // Context:     Is called to get descriptive string on arbitrary IJLERR code.
    //
    // Returns:     pointer to string
    //
    // Parameters:  IJLERR - IJL error code
    //
    ////////////////////////////////////////////////////////////////////////////
    *F*/

    IJLAPI(const LPCTSTR, ijlErrorStr, (IJLERR code));

    #if defined( __cplusplus )
    }
    #endif

    #endif  // __IJL_H__

Currently browsing [JpegDumper.zip] (72,443 bytes) - [jpeg.cpp] - (4,306 bytes)

    // ** JPEG.CPP, the code used to wrap IJL

    //############################################################################
    //##                                                                        ##
    //##  JPEG.CPP                                                              ##
    //##                                                                        ##
    //##  Wrapper class to load a jpeg from a block of memory.                  ##
    //##                                                                        ##
    //##  OpenSourced 2/4/2000 by John W. Ratcliff                              ##
    //##                                                                        ##
    //##  No warranty expressed or implied.  Released as part of the triangle   ##
    //##  throughput testbed project.                                           ##
    //############################################################################
    //##                                                                        ##
    //##  Contact John W. Ratcliff at jratcliff@verant.com                      ##
    //############################################################################
    #include "stdafx.h"
    #include "jpeg.h"
    #include "ijl.h" // intel jpeg library header file.

    // read image into this buffer.
    void * Jpeg::ReadImage(int &width,
                           int &height,
                           int &nchannels,
                           const void *buffer,
                           int sizebytes)
    {
      JPEG_CORE_PROPERTIES jcprops;

      if ( ijlInit(&jcprops) != IJL_OK )
      {
        ijlFree(&jcprops);
        return 0;
      }

      jcprops.JPGBytes = (unsigned char *) buffer;
      jcprops.JPGSizeBytes = sizebytes;
      jcprops.jquality = 100;

      if ( ijlRead(&jcprops,IJL_JBUFF_READPARAMS) != IJL_OK )
      {
        ijlFree(&jcprops);
        return 0;
      }

      width  = jcprops.JPGWidth;
      height = jcprops.JPGHeight;
      IJLIOTYPE mode;

      mode = IJL_JBUFF_READWHOLEIMAGE;
      nchannels = jcprops.JPGChannels;
      unsigned char * pixbuff = new unsigned char[width*height*nchannels];
      if ( !pixbuff )
      {
        ijlFree(&jcprops);
        return 0;
      }

      jcprops.DIBWidth  = width;
      jcprops.DIBHeight = height;
      jcprops.DIBChannels = nchannels;
      jcprops.DIBPadBytes = 0;
      jcprops.DIBBytes = (unsigned char *)pixbuff;

      if ( jcprops.JPGChannels == 3 )
      {
        jcprops.DIBColor = IJL_RGB;
        jcprops.JPGColor = IJL_YCBCR;
        jcprops.JPGSubsampling = IJL_411;
        jcprops.DIBSubsampling = (IJL_DIBSUBSAMPLING) 0;
      }
      else
      {
        jcprops.DIBColor = IJL_G;
        jcprops.JPGColor = IJL_G;
        jcprops.JPGSubsampling = (IJL_JPGSUBSAMPLING) 0;
        jcprops.DIBSubsampling = (IJL_DIBSUBSAMPLING) 0;
      }

      if ( ijlRead(&jcprops, mode) != IJL_OK )
      {
        ijlFree(&jcprops);
        return 0;
      }

      if ( ijlFree(&jcprops) != IJL_OK ) return 0;

      return (void *)pixbuff;
    }

    void * Jpeg::Compress(const void *source,
                          int width,
                          int height,
                          int bpp,
                          int &len,
                          int quality)
    {
      JPEG_CORE_PROPERTIES jcprops;

      if ( ijlInit(&jcprops) != IJL_OK )
      {
        ijlFree(&jcprops);
        return false;
      }

      jcprops.DIBWidth    = width;
      jcprops.DIBHeight   = height;
      jcprops.JPGWidth    = width;
      jcprops.JPGHeight   = height;
      jcprops.DIBBytes    = (unsigned char *) source;
      jcprops.DIBPadBytes = 0;
      jcprops.DIBChannels = bpp;
      jcprops.JPGChannels = bpp;

      if ( bpp == 3 )
      {
        jcprops.DIBColor = IJL_RGB;
        jcprops.JPGColor = IJL_YCBCR;
        jcprops.JPGSubsampling = IJL_411;
        jcprops.DIBSubsampling = (IJL_DIBSUBSAMPLING) 0;
      }
      else
      {
        jcprops.DIBColor = IJL_G;
        jcprops.JPGColor = IJL_G;
        jcprops.JPGSubsampling = (IJL_JPGSUBSAMPLING) 0;
        jcprops.DIBSubsampling = (IJL_DIBSUBSAMPLING) 0;
      }

      int size = width*height*bpp;

      unsigned char * buffer = new unsigned char[size];

      jcprops.JPGSizeBytes = size;
      jcprops.JPGBytes     = buffer;

      jcprops.jquality = quality;

      if ( ijlWrite(&jcprops,IJL_JBUFF_WRITEWHOLEIMAGE) != IJL_OK )
      {
        ijlFree(&jcprops);
        return 0;
      }

      len = jcprops.JPGSizeBytes;
      if ( ijlFree(&jcprops) != IJL_OK )
      {
        return 0;
      }

      return buffer;
    }

Currently browsing [JpegDumper.zip] (72,443 bytes) - [jpeg.h] - (2,068 bytes)

    // *** The JPEG.H wrapper layer header file.

    #ifndef JPEG_H

    #define JPEG_H

    //############################################################################
    //##                                                                        ##
    //##  JPEG.H                                                                ##
    //##                                                                        ##
    //##  Wrapper class to compress or decompress a jpeg from a block of memory ##
    //##  using the Intel Jpeg Library.                                         ##
    //##  OpenSourced 2/4/2000 by John W. Ratcliff                              ##
    //##                                                                        ##
    //##  No warranty expressed or implied.  Released as part of the triangle   ##
    //##  throughput testbed project.                                           ##
    //############################################################################
    //##                                                                        ##
    //##  Contact John W. Ratcliff at jratcliff@verant.com                      ##
    //############################################################################

    class Jpeg
    {
    public:

      static void *ReadImage(int &width,   // width of the image loaded.
                             int &height,  // height of the image loaded.
                             int &bpp,     // BYTES (not bits) PER PIXEL.
                             const void *buffer, // memory address containing jpeg compressed data.
                             int sizebytes); // size of jpeg compressed data.

      static void * Compress(const void *buffer, // address of image in memory
                             int width, // width of image in pixels
                             int height, // height of image in pixels.
                             int bpp, // *BYTES* per pixel of image 1 or 3
                             int &len, // returns length of compressed data
                             int quality=75); // image quality as a percentage

    };

    #endif

The zip file viewer built into the Developer Toolbox made use of the zlib library, as well as the zlibdll source additions.

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