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📄 wrjpgcom.c

📁 这是在PCA下的基于IPP库示例代码例子,在网上下了IPP的库之后,设置相关参数就可以编译该代码.
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/* * wrjpgcom.c * * Copyright (C) 1994-1997, Thomas G. Lane. * This file is part of the Independent JPEG Group's software. * For conditions of distribution and use, see the accompanying README file. * * This file contains a very simple stand-alone application that inserts * user-supplied text as a COM (comment) marker in a JFIF file. * This may be useful as an example of the minimum logic needed to parse * JPEG markers. */#define JPEG_CJPEG_DJPEG  /* to get the command-line config symbols */#include "jinclude.h"   /* get auto-config symbols, <stdio.h> */#ifndef HAVE_STDLIB_H   /* <stdlib.h> should declare malloc() */extern void * malloc ();#endif#include <ctype.h>    /* to declare isupper(), tolower() */#ifdef USE_SETMODE#include <fcntl.h>    /* to declare setmode()'s parameter macros *//* If you have setmode() but not <io.h>, just delete this line: */#include <io.h>     /* to declare setmode() */#endif#ifdef USE_CCOMMAND   /* command-line reader for Macintosh */#ifdef __MWERKS__#include <SIOUX.h>              /* Metrowerks needs this */#include <console.h>    /* ... and this */#endif#ifdef THINK_C#include <console.h>    /* Think declares it here */#endif#endif#ifdef DONT_USE_B_MODE    /* define mode parameters for fopen() */#define READ_BINARY "r"#define WRITE_BINARY  "w"#else#ifdef VMS      /* VMS is very nonstandard */#define READ_BINARY "rb", "ctx=stm"#define WRITE_BINARY  "wb", "ctx=stm"#else       /* standard ANSI-compliant case */#define READ_BINARY "rb"#define WRITE_BINARY  "wb"#endif#endif#ifndef EXIT_FAILURE    /* define exit() codes if not provided */#define EXIT_FAILURE  1#endif#ifndef EXIT_SUCCESS#ifdef VMS#define EXIT_SUCCESS  1   /* VMS is very nonstandard */#else#define EXIT_SUCCESS  0#endif#endif/* Reduce this value if your malloc() can't allocate blocks up to 64K. * On DOS, compiling in large model is usually a better solution. */#ifndef MAX_COM_LENGTH#define MAX_COM_LENGTH 65000L /* must be <= 65533 in any case */#endif/* * These macros are used to read the input file and write the output file. * To reuse this code in another application, you might need to change these. */static FILE * infile;   /* input JPEG file *//* Return next input byte, or EOF if no more */#define NEXTBYTE()  getc(infile)static FILE * outfile;    /* output JPEG file *//* Emit an output byte */#define PUTBYTE(x)  putc((x), outfile)/* Error exit handler */#define ERREXIT(msg)  (fprintf(stderr, "%s\n", msg), exit(EXIT_FAILURE))/* Read one byte, testing for EOF */static intread_1_byte (void){  int c;  c = NEXTBYTE();  if (c == EOF)    ERREXIT("Premature EOF in JPEG file");  return c;}/* Read 2 bytes, convert to unsigned int *//* All 2-byte quantities in JPEG markers are MSB first */static unsigned intread_2_bytes (void){  int c1, c2;  c1 = NEXTBYTE();  if (c1 == EOF)    ERREXIT("Premature EOF in JPEG file");  c2 = NEXTBYTE();  if (c2 == EOF)    ERREXIT("Premature EOF in JPEG file");  return (((unsigned int) c1) << 8) + ((unsigned int) c2);}/* Routines to write data to output file */static voidwrite_1_byte (int c){  PUTBYTE(c);}static voidwrite_2_bytes (unsigned int val){  PUTBYTE((val >> 8) & 0xFF);  PUTBYTE(val & 0xFF);}static voidwrite_marker (int marker){  PUTBYTE(0xFF);  PUTBYTE(marker);}static voidcopy_rest_of_file (void){  int c;  while ((c = NEXTBYTE()) != EOF)    PUTBYTE(c);}/* * JPEG markers consist of one or more 0xFF bytes, followed by a marker * code byte (which is not an FF).  Here are the marker codes of interest * in this program.  (See jdmarker.c for a more complete list.) */#define M_SOF0  0xC0    /* Start Of Frame N */#define M_SOF1  0xC1    /* N indicates which compression process */#define M_SOF2  0xC2    /* Only SOF0-SOF2 are now in common use */#define M_SOF3  0xC3#define M_SOF5  0xC5    /* NB: codes C4 and CC are NOT SOF markers */#define M_SOF6  0xC6#define M_SOF7  0xC7#define M_SOF9  0xC9#define M_SOF10 0xCA#define M_SOF11 0xCB#define M_SOF13 0xCD#define M_SOF14 0xCE#define M_SOF15 0xCF#define M_SOI   0xD8    /* Start Of Image (beginning of datastream) */#define M_EOI   0xD9    /* End Of Image (end of datastream) */#define M_SOS   0xDA    /* Start Of Scan (begins compressed data) */#define M_COM   0xFE    /* COMment *//* * Find the next JPEG marker and return its marker code. * We expect at least one FF byte, possibly more if the compressor used FFs * to pad the file.  (Padding FFs will NOT be replicated in the output file.) * There could also be non-FF garbage between markers.  The treatment of such * garbage is unspecified; we choose to skip over it but emit a warning msg. * NB: this routine must not be used after seeing SOS marker, since it will * not deal correctly with FF/00 sequences in the compressed image data... */static intnext_marker (void){  int c;  int discarded_bytes = 0;  /* Find 0xFF byte; count and skip any non-FFs. */  c = read_1_byte();  while (c != 0xFF) {    discarded_bytes++;    c = read_1_byte();  }  /* Get marker code byte, swallowing any duplicate FF bytes.  Extra FFs   * are legal as pad bytes, so don't count them in discarded_bytes.   */  do {    c = read_1_byte();  } while (c == 0xFF);  if (discarded_bytes != 0) {    fprintf(stderr, "Warning: garbage data found in JPEG file\n");  }  return c;}/* * Read the initial marker, which should be SOI. * For a JFIF file, the first two bytes of the file should be literally * 0xFF M_SOI.  To be more general, we could use next_marker, but if the * input file weren't actually JPEG at all, next_marker might read the whole * file and then return a misleading error message... */static intfirst_marker (void){  int c1, c2;  c1 = NEXTBYTE();  c2 = NEXTBYTE();  if (c1 != 0xFF || c2 != M_SOI)    ERREXIT("Not a JPEG file");  return c2;}/* * Most types of marker are followed by a variable-length parameter segment. * This routine skips over the parameters for any marker we don't otherwise * want to process. * Note that we MUST skip the parameter segment explicitly in order not to * be fooled by 0xFF bytes that might appear within the parameter segment; * such bytes do NOT introduce new markers. */static voidcopy_variable (void)/* Copy an unknown or uninteresting variable-length marker */{  unsigned int length;  /* Get the marker parameter length count */  length = read_2_bytes();  write_2_bytes(length);  /* Length includes itself, so must be at least 2 */  if (length < 2)    ERREXIT("Erroneous JPEG marker length");  length -= 2;  /* Skip over the remaining bytes */  while (length > 0) {    write_1_byte(read_1_byte());    length--;  }}static voidskip_variable (void)/* Skip over an unknown or uninteresting variable-length marker */{  unsigned int length;  /* Get the marker parameter length count */  length = read_2_bytes();  /* Length includes itself, so must be at least 2 */  if (length < 2)    ERREXIT("Erroneous JPEG marker length");  length -= 2;  /* Skip over the remaining bytes */  while (length > 0) {    (void) read_1_byte();    length--;  }}/* * Parse the marker stream until SOFn or EOI is seen; * copy data to output, but discard COM markers unless keep_COM is true. */static intscan_JPEG_header (int keep_COM){  int marker;

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