gd_jpeg.c

Linux/Unix下的绘图函数库（Graphic Drawing Library）

/*
 * gd_jpeg.c: Read and write JPEG (JFIF) format image files using the
 * gd graphics library (http://www.boutell.com/gd/).
 * 
 * This software is based in part on the work of the Independent JPEG
 * Group.  For more information on the IJG JPEG software (and JPEG
 * documentation, etc.), see ftp://ftp.uu.net/graphics/jpeg/.
 *
 * NOTE: IJG 12-bit JSAMPLE (BITS_IN_JSAMPLE == 12) mode is not
 * supported at all on read in gd 2.0, and is not supported on write
 * except for palette images, which is sort of pointless (TBB). Even that
 * has never been tested according to DB.
 *
 * Copyright 2000 Doug Becker, mailto:[e-mail]
 *
 * Modification 4/18/00 TBB: JPEG_DEBUG rather than just DEBUG,
 * so VC++ builds don't spew to standard output, causing
 * major CGI brain damage
 *
 * 2.0.10: more efficient gdImageCreateFromJpegCtx, thanks to
 * Christian Aberger 
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdio.h>
#include <stdlib.h>
#include <setjmp.h>
#include <limits.h>
#include <string.h>

#include "gd.h"
/* TBB: move this up so include files are not brought in */
/* JCE: arrange HAVE_LIBJPEG so that it can be set in gd.h */
#ifdef HAVE_LIBJPEG
#include "gdhelpers.h"

/* JCE undef two symbols that we don't need anymore but which are
   may be defined in config.h from ./configure but which are
   redefined incompatibly in jpeglib.h */
#undef HAVE_STDDEF_H
#undef HAVE_STDLIB_H

/* 1.8.1: remove dependency on jinclude.h */
#include "jpeglib.h"
#include "jerror.h"

static const char *const GD_JPEG_VERSION = "1.0";

typedef struct _jmpbuf_wrapper
{
  jmp_buf jmpbuf;
}
jmpbuf_wrapper;

/* Called by the IJG JPEG library upon encountering a fatal error */
static void
fatal_jpeg_error (j_common_ptr cinfo)
{
  jmpbuf_wrapper *jmpbufw;

  fprintf (stderr, "gd-jpeg: JPEG library reports unrecoverable error: ");
  (*cinfo->err->output_message) (cinfo);
  fflush (stderr);

  jmpbufw = (jmpbuf_wrapper *) cinfo->client_data;
  jpeg_destroy (cinfo);

  if (jmpbufw != 0)
    {
      longjmp (jmpbufw->jmpbuf, 1);
      fprintf (stderr, "gd-jpeg: EXTREMELY fatal error: longjmp"
	       " returned control; terminating\n");
    }
  else
    {
      fprintf (stderr, "gd-jpeg: EXTREMELY fatal error: jmpbuf"
	       " unrecoverable; terminating\n");
    }

  fflush (stderr);
  exit (99);
}

/*
 * Write IM to OUTFILE as a JFIF-formatted JPEG image, using quality
 * QUALITY.  If QUALITY is in the range 0-100, increasing values
 * represent higher quality but also larger image size.  If QUALITY is
 * negative, the IJG JPEG library's default quality is used (which
 * should be near optimal for many applications).  See the IJG JPEG
 * library documentation for more details.  */

BGD_DECLARE(void) gdImageJpeg (gdImagePtr im, FILE * outFile, int quality)
{
  gdIOCtx *out = gdNewFileCtx (outFile);
  gdImageJpegCtx (im, out, quality);
  out->gd_free (out);
}

BGD_DECLARE(void *) gdImageJpegPtr (gdImagePtr im, int *size, int quality)
{
  void *rv;
  gdIOCtx *out = gdNewDynamicCtx (2048, NULL);
  gdImageJpegCtx (im, out, quality);
  rv = gdDPExtractData (out, size);
  out->gd_free (out);
  return rv;
}

void jpeg_gdIOCtx_dest (j_compress_ptr cinfo, gdIOCtx * outfile);

BGD_DECLARE(void) gdImageJpegCtx (gdImagePtr im, gdIOCtx * outfile, int quality)
{
  struct jpeg_compress_struct cinfo;
  struct jpeg_error_mgr jerr;
  int i, j, jidx;
  /* volatile so we can gdFree it on return from longjmp */
  volatile JSAMPROW row = 0;
  JSAMPROW rowptr[1];
  jmpbuf_wrapper jmpbufw;
  JDIMENSION nlines;
  char comment[255];

#ifdef JPEG_DEBUG
  printf ("gd-jpeg: gd JPEG version %s\n", GD_JPEG_VERSION);
  printf ("gd-jpeg: JPEG library version %d, %d-bit sample values\n",
	  JPEG_LIB_VERSION, BITS_IN_JSAMPLE);
  if (!im->trueColor)
    {
      for (i = 0; i < im->colorsTotal; i++)
	{
	  if (!im->open[i])
	    printf ("gd-jpeg: gd colormap index %d: (%d, %d, %d)\n", i,
		    im->red[i], im->green[i], im->blue[i]);
	}
    }
#endif /* JPEG_DEBUG */

  memset (&cinfo, 0, sizeof (cinfo));
  memset (&jerr, 0, sizeof (jerr));

  cinfo.err = jpeg_std_error (&jerr);
  cinfo.client_data = &jmpbufw;
  if (setjmp (jmpbufw.jmpbuf) != 0)
    {
      /* we're here courtesy of longjmp */
      if (row)
	gdFree (row);
      return;
    }

  cinfo.err->error_exit = fatal_jpeg_error;

  jpeg_create_compress (&cinfo);

  cinfo.image_width = im->sx;
  cinfo.image_height = im->sy;
  cinfo.input_components = 3;	/* # of color components per pixel */
  cinfo.in_color_space = JCS_RGB;	/* colorspace of input image */
  jpeg_set_defaults (&cinfo);
  if (quality >= 0)
    jpeg_set_quality (&cinfo, quality, TRUE);

  /* If user requests interlace, translate that to progressive JPEG */
  if (gdImageGetInterlaced (im))
    {
#ifdef JPEG_DEBUG
      printf ("gd-jpeg: interlace set, outputting progressive"
	      " JPEG image\n");
#endif
      jpeg_simple_progression (&cinfo);
    }

  jpeg_gdIOCtx_dest (&cinfo, outfile);

  row = (JSAMPROW) gdCalloc (1, cinfo.image_width * cinfo.input_components
			     * sizeof (JSAMPLE));
  if (row == 0)
    {
      fprintf (stderr, "gd-jpeg: error: unable to allocate JPEG row "
	       "structure: gdCalloc returns NULL\n");
      jpeg_destroy_compress (&cinfo);
      return;
    }

  rowptr[0] = row;

  jpeg_start_compress (&cinfo, TRUE);

  sprintf (comment, "CREATOR: gd-jpeg v%s (using IJG JPEG v%d),",
	   GD_JPEG_VERSION, JPEG_LIB_VERSION);
  if (quality >= 0)
    sprintf (comment + strlen (comment), " quality = %d\n", quality);
  else
    strcat (comment + strlen (comment), " default quality\n");
  jpeg_write_marker (&cinfo, JPEG_COM, (unsigned char *) comment,
		     (unsigned int) strlen (comment));
  if (im->trueColor)
    {
#if BITS_IN_JSAMPLE == 12
      fprintf (stderr,
	       "gd-jpeg: error: jpeg library was compiled for 12-bit\n"
	       "precision. This is mostly useless, because JPEGs on the web are\n"
	       "8-bit and such versions of the jpeg library won't read or write\n"
	       "them. GD doesn't support these unusual images. Edit your\n"
	       "jmorecfg.h file to specify the correct precision and completely\n"
	       "'make clean' and 'make install' libjpeg again. Sorry.\n");
      goto error;
#endif /* BITS_IN_JSAMPLE == 12 */
      for (i = 0; i < im->sy; i++)
	{
	  for (jidx = 0, j = 0; j < im->sx; j++)
	    {
	      int val = im->tpixels[i][j];
	      row[jidx++] = gdTrueColorGetRed (val);
	      row[jidx++] = gdTrueColorGetGreen (val);
	      row[jidx++] = gdTrueColorGetBlue (val);
	    }

	  nlines = jpeg_write_scanlines (&cinfo, rowptr, 1);
	  if (nlines != 1)
	    fprintf (stderr, "gd_jpeg: warning: jpeg_write_scanlines"
		     " returns %u -- expected 1\n", nlines);
	}
    }
  else
    {
      for (i = 0; i < im->sy; i++)
	{
	  for (jidx = 0, j = 0; j < im->sx; j++)
	    {
	      int idx = im->pixels[i][j];

	      /*
	       * NB: Although gd RGB values are ints, their max value is
	       * 255 (see the documentation for gdImageColorAllocate())
	       * -- perfect for 8-bit JPEG encoding (which is the norm)
	       */
#if BITS_IN_JSAMPLE == 8
	      row[jidx++] = im->red[idx];
	      row[jidx++] = im->green[idx];
	      row[jidx++] = im->blue[idx];
#elif BITS_IN_JSAMPLE == 12
	      row[jidx++] = im->red[idx] << 4;
	      row[jidx++] = im->green[idx] << 4;
	      row[jidx++] = im->blue[idx] << 4;
#else
#error IJG JPEG library BITS_IN_JSAMPLE value must be 8 or 12
#endif
	    }

	  nlines = jpeg_write_scanlines (&cinfo, rowptr, 1);
	  if (nlines != 1)
	    fprintf (stderr, "gd_jpeg: warning: jpeg_write_scanlines"
		     " returns %u -- expected 1\n", nlines);
	}
    }
  jpeg_finish_compress (&cinfo);
  jpeg_destroy_compress (&cinfo);
  gdFree (row);
}

BGD_DECLARE(gdImagePtr) gdImageCreateFromJpeg (FILE * inFile)
{
  gdImagePtr im;
  gdIOCtx *in = gdNewFileCtx (inFile);
  im = gdImageCreateFromJpegCtx (in);
  in->gd_free (in);
  return im;
}

BGD_DECLARE(gdImagePtr) gdImageCreateFromJpegPtr (int size, void *data)
{
  gdImagePtr im;
  gdIOCtx *in = gdNewDynamicCtxEx (size, data, 0);
  im = gdImageCreateFromJpegCtx (in);
  in->gd_free (in);
  return im;
}

void jpeg_gdIOCtx_src (j_decompress_ptr cinfo, gdIOCtx * infile);

static int CMYKToRGB (int c, int m, int y, int k, int inverted);

/* 
 * Create a gd-format image from the JPEG-format INFILE.  Returns the
 * image, or NULL upon error.
 */
BGD_DECLARE(gdImagePtr) gdImageCreateFromJpegCtx (gdIOCtx * infile)
{
  struct jpeg_decompress_struct cinfo;
  struct jpeg_error_mgr jerr;
  jmpbuf_wrapper jmpbufw;
  /* volatile so we can gdFree them after longjmp */
  volatile JSAMPROW row = 0;
  volatile gdImagePtr im = 0;
  JSAMPROW rowptr[1];
  int i, j, retval;
  JDIMENSION nrows;
  int channels = 3;
  int inverted = 0;
#ifdef JPEG_DEBUG
  printf ("gd-jpeg: gd JPEG version %s\n", GD_JPEG_VERSION);
  printf ("gd-jpeg: JPEG library version %d, %d-bit sample values\n",
	  JPEG_LIB_VERSION, BITS_IN_JSAMPLE);
#endif

  memset (&cinfo, 0, sizeof (cinfo));
  memset (&jerr, 0, sizeof (jerr));

  cinfo.err = jpeg_std_error (&jerr);
  cinfo.client_data = &jmpbufw;
  if (setjmp (jmpbufw.jmpbuf) != 0)
    {
      /* we're here courtesy of longjmp */
      if (row)
	gdFree (row);
      if (im)
	gdImageDestroy (im);
      return 0;
    }

  cinfo.err->error_exit = fatal_jpeg_error;

  jpeg_create_decompress (&cinfo);

  jpeg_gdIOCtx_src (&cinfo, infile);

  /* 2.0.22: save the APP14 marker to check for Adobe Photoshop CMYK
     files with inverted components. */
  jpeg_save_markers (&cinfo, JPEG_APP0 + 14, 256);

  retval = jpeg_read_header (&cinfo, TRUE);
  if (retval != JPEG_HEADER_OK)
    fprintf (stderr, "gd-jpeg: warning: jpeg_read_header returns"
	     " %d, expected %d\n", retval, JPEG_HEADER_OK);

  if (cinfo.image_height > INT_MAX)
    fprintf (stderr, "gd-jpeg: warning: JPEG image height (%u) is"
	     " greater than INT_MAX (%d) (and thus greater than"
	     " gd can handle)", cinfo.image_height, INT_MAX);

  if (cinfo.image_width > INT_MAX)
    fprintf (stderr, "gd-jpeg: warning: JPEG image width (%u) is"
	     " greater than INT_MAX (%d) (and thus greater than"
	     " gd can handle)\n", cinfo.image_width, INT_MAX);

  im = gdImageCreateTrueColor ((int) cinfo.image_width,
			       (int) cinfo.image_height);
  if (im == 0)
    {
      fprintf (stderr, "gd-jpeg error: cannot allocate gdImage" " struct\n");
      goto error;
    }
  /* 2.0.22: very basic support for reading CMYK colorspace files. Nice for
     thumbnails but there's no support for fussy adjustment of the
     assumed properties of inks and paper. */
  if ((cinfo.jpeg_color_space == JCS_CMYK) ||
      (cinfo.jpeg_color_space == JCS_YCCK))
    {
      cinfo.out_color_space = JCS_CMYK;
    }
  else
    {
      cinfo.out_color_space = JCS_RGB;
    }

  if (jpeg_start_decompress (&cinfo) != TRUE)
    fprintf (stderr, "gd-jpeg: warning: jpeg_start_decompress"
	     " reports suspended data source\n");

#ifdef JPEG_DEBUG
  printf ("gd-jpeg: JPEG image information:");
  if (cinfo.saw_JFIF_marker)
    printf (" JFIF version %d.%.2d",
	    (int) cinfo.JFIF_major_version, (int) cinfo.JFIF_minor_version);
  else if (cinfo.saw_Adobe_marker)
    printf (" Adobe format");
  else
    printf (" UNKNOWN format");

  printf (" %ux%u (raw) / %ux%u (scaled) %d-bit", cinfo.image_width,
	  cinfo.image_height, cinfo.output_width,
	  cinfo.output_height, cinfo.data_precision);
  printf (" %s", (cinfo.progressive_mode ? "progressive" : "baseline"));
  printf (" image, %d quantized colors, ", cinfo.actual_number_of_colors);

  switch (cinfo.jpeg_color_space)
    {
    case JCS_GRAYSCALE:
      printf ("grayscale");
      break;

    case JCS_RGB:
      printf ("RGB");
      break;

    case JCS_YCbCr:
      printf ("YCbCr (a.k.a. YUV)");
      break;

    case JCS_CMYK:
      printf ("CMYK");
      break;

    case JCS_YCCK:
      printf ("YCbCrK");
      break;

    default:
      printf ("UNKNOWN (value: %d)", (int) cinfo.jpeg_color_space);
      break;
    }
  printf (" colorspace\n");
  fflush (stdout);
#endif /* JPEG_DEBUG */

  /* REMOVED by TBB 2/12/01. This field of the structure is
     documented as private, and sure enough it's gone in the
     latest libjpeg, replaced by something else. Unfortunately
     there is still no right way to find out if the file was
     progressive or not; just declare your intent before you
     write one by calling gdImageInterlace(im, 1) yourself. 
     After all, we're not really supposed to rework JPEGs and
     write them out again anyway. Lossy compression, remember? */
#if 0
  gdImageInterlace (im, cinfo.progressive_mode != 0);
#endif
  if (cinfo.out_color_space == JCS_RGB)
    {
      if (cinfo.output_components != 3)
	{
	  fprintf (stderr, "gd-jpeg: error: JPEG color quantization"
		   " request resulted in output_components == %d"
		   " (expected 3 for RGB)\n", cinfo.output_components);
	  goto error;
	}
      channels = 3;
    }
  else if (cinfo.out_color_space == JCS_CMYK)
    {
      jpeg_saved_marker_ptr marker;
      if (cinfo.output_components != 4)
	{
	  fprintf (stderr, "gd-jpeg: error: JPEG color quantization"
		   " request resulted in output_components == %d"
		   " (expected 4 for CMYK)\n", cinfo.output_components);
	  goto error;
	}
      channels = 4;
      marker = cinfo.marker_list;
      while (marker)
	{
	  if ((marker->marker == (JPEG_APP0 + 14)) &&
	      (marker->data_length >= 12)
	      && (!strncmp ((const char *) marker->data, "Adobe", 5)))
	    {
	      inverted = 1;
	      break;
	    }
	  marker = marker->next;
	}
    }
  else
    {
      fprintf (stderr, "gd-jpeg: error: unexpected colorspace\n");
      goto error;
    }
#if BITS_IN_JSAMPLE == 12
  fprintf (stderr, "gd-jpeg: error: jpeg library was compiled for 12-bit\n"
	   "precision. This is mostly useless, because JPEGs on the web are\n"
	   "8-bit and such versions of the jpeg library won't read or write\n"
	   "them. GD doesn't support these unusual images. Edit your\n"
	   "jmorecfg.h file to specify the correct precision and completely\n"
	   "'make clean' and 'make install' libjpeg again. Sorry.\n");
  goto error;
#endif /* BITS_IN_JSAMPLE == 12 */

  row = gdCalloc (cinfo.output_width * channels, sizeof (JSAMPLE));
  if (row == 0)
    {
      fprintf (stderr, "gd-jpeg: error: unable to allocate row for"
	       " JPEG scanline: gdCalloc returns NULL\n");
      goto error;
    }
  rowptr[0] = row;
  if (cinfo.out_color_space == JCS_CMYK)
    {
      for (i = 0; i < cinfo.output_height; i++)
	{
	  register JSAMPROW currow = row;
	  register int *tpix = im->tpixels[i];
	  nrows = jpeg_read_scanlines (&cinfo, rowptr, 1);
	  if (nrows != 1)