Functions to write markers

1 files changed, 724 insertions, 0 deletions

diff --git a/src/c_marker.c b/src/c_marker.c
new file mode 100644
index 0000000..c6e1837
--- /dev/null
+++ b/src/c_marker.c
@@ -0,0 +1,724 @@
+/*
+ * jcmarker.c
+ *
+ * Copyright (C) 1991-1998, 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 routines to write JPEG datastream markers.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "morecfg.h"
+#include "jpeglib.h"
+
+/*
+ * jpeg_natural_order[i] is the natural-order position of the i'th element
+ * of zigzag order.
+ *
+ * When reading corrupted data, the Huffman decoders could attempt
+ * to reference an entry beyond the end of this array (if the decoded
+ * zero run length reaches past the end of the block).  To prevent
+ * wild stores without adding an inner-loop test, we put some extra
+ * "63"s after the real entries.  This will cause the extra coefficient
+ * to be stored in location 63 of the block, not somewhere random.
+ * The worst case would be a run-length of 15, which means we need 16
+ * fake entries.
+ */
+
+const int jpeg_natural_order[DCTSIZE2+16] = {
+  0,  1,  8, 16,  9,  2,  3, 10,
+ 17, 24, 32, 25, 18, 11,  4,  5,
+ 12, 19, 26, 33, 40, 48, 41, 34,
+ 27, 20, 13,  6,  7, 14, 21, 28,
+ 35, 42, 49, 56, 57, 50, 43, 36,
+ 29, 22, 15, 23, 30, 37, 44, 51,
+ 58, 59, 52, 45, 38, 31, 39, 46,
+ 53, 60, 61, 54, 47, 55, 62, 63,
+ 63, 63, 63, 63, 63, 63, 63, 63, /* extra entries for safety in decoder */
+ 63, 63, 63, 63, 63, 63, 63, 63
+};
+
+
+typedef enum {			/* JPEG marker codes */
+  M_SOF0  = 0xc0,
+  M_SOF1  = 0xc1,
+  M_SOF2  = 0xc2,
+  M_SOF3  = 0xc3,
+  
+  M_SOF5  = 0xc5,
+  M_SOF6  = 0xc6,
+  M_SOF7  = 0xc7,
+  
+  M_JPG   = 0xc8,
+  M_SOF9  = 0xc9,
+  M_SOF10 = 0xca,
+  M_SOF11 = 0xcb,
+  
+  M_SOF13 = 0xcd,
+  M_SOF14 = 0xce,
+  M_SOF15 = 0xcf,
+  
+  M_DHT   = 0xc4,
+  
+  M_DAC   = 0xcc,
+  
+  M_RST0  = 0xd0,
+  M_RST1  = 0xd1,
+  M_RST2  = 0xd2,
+  M_RST3  = 0xd3,
+  M_RST4  = 0xd4,
+  M_RST5  = 0xd5,
+  M_RST6  = 0xd6,
+  M_RST7  = 0xd7,
+  
+  M_SOI   = 0xd8,
+  M_EOI   = 0xd9,
+  M_SOS   = 0xda,
+  M_DQT   = 0xdb,
+  M_DNL   = 0xdc,
+  M_DRI   = 0xdd,
+  M_DHP   = 0xde,
+  M_EXP   = 0xdf,
+  
+  M_APP0  = 0xe0,
+  M_APP1  = 0xe1,
+  M_APP2  = 0xe2,
+  M_APP3  = 0xe3,
+  M_APP4  = 0xe4,
+  M_APP5  = 0xe5,
+  M_APP6  = 0xe6,
+  M_APP7  = 0xe7,
+  M_APP8  = 0xe8,
+  M_APP9  = 0xe9,
+  M_APP10 = 0xea,
+  M_APP11 = 0xeb,
+  M_APP12 = 0xec,
+  M_APP13 = 0xed,
+  M_APP14 = 0xee,
+  M_APP15 = 0xef,
+  
+  M_JPG0  = 0xf0,
+  M_JPG13 = 0xfd,
+  M_COM   = 0xfe,
+  
+  M_TEM   = 0x01,
+  
+  M_ERROR = 0x100
+} JPEG_MARKER;
+
+#define OUTPUT_BUF_SIZE  4096        /* choose an efficiently fwrite'able size */
+
+/* Expanded data destination object for stdio output */
+
+typedef struct {
+  struct jpeg_destination_mgr pub; /* public fields */
+
+  FILE *outfile;		/* target stream */
+  JOCTET buffer[OUTPUT_BUF_SIZE];		/* start of buffer */
+} my_destination_mgr;
+
+
+/*
+ * Empty the output buffer --- called whenever buffer fills up.
+ *
+ * In typical applications, this should write the entire output buffer
+ * (ignoring the current state of next_output_byte & free_in_buffer),
+ * reset the pointer & count to the start of the buffer, and return TRUE
+ * indicating that the buffer has been dumped.
+ *
+ * In applications that need to be able to suspend compression due to output
+ * overrun, a FALSE return indicates that the buffer cannot be emptied now.
+ * In this situation, the compressor will return to its caller (possibly with
+ * an indication that it has not accepted all the supplied scanlines).  The
+ * application should resume compression after it has made more room in the
+ * output buffer.  Note that there are substantial restrictions on the use of
+ * suspension --- see the documentation.
+ *
+ * When suspending, the compressor will back up to a convenient restart point
+ * (typically the start of the current MCU). next_output_byte & free_in_buffer
+ * indicate where the restart point will be if the current call returns FALSE.
+ * Data beyond this point will be regenerated after resumption, so do not
+ * write it out when emptying the buffer externally.
+ */
+
+boolean empty_output_buffer (my_destination_mgr *destination) {
+  my_destination_mgr *dest = destination;
+
+  if (fwrite(dest->buffer, 1, OUTPUT_BUF_SIZE, dest->outfile) != OUTPUT_BUF_SIZE) {
+   perror("Output file write error --- out of disk space?");
+   exit(1);
+   /* ERREXIT(cinfo, JERR_FILE_WRITE);*/
+  }
+
+  dest->pub.next_output_byte = dest->buffer;
+  dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
+
+  return TRUE;
+}
+
+
+/*
+ * Basic output routines.
+ *
+ * Note that we do not support suspension while writing a marker.
+ * Therefore, an application using suspension must ensure that there is
+ * enough buffer space for the initial markers (typ. 600-700 bytes) before
+ * calling jpeg_start_compress, and enough space to write the trailing EOI
+ * (a few bytes) before calling jpeg_finish_compress.  Multipass compression
+ * modes are not supported at all with suspension, so those two are the only
+ * points where markers will be written.
+ */
+
+void emit_byte (my_destination_mgr *destination, int val) /* Emit a byte */ {
+  my_destination_mgr *dest = destination;
+
+  *(dest->pub.next_output_byte)++ = (JOCTET) val;
+  if ((--dest->pub.free_in_buffer) == 0) {
+    if (! empty_output_buffer(destination)) {
+      perror("Suspension not allowed here");
+      exit(1);
+      /*ERREXIT(cinfo, JERR_CANT_SUSPEND);*/
+    }
+  }
+}
+
+static void emit_marker (my_destination_mgr *destination, JPEG_MARKER mark) /* Emit a marker code */ {
+  emit_byte(destination, 0xFF);
+  emit_byte(destination, (int) mark);
+}
+
+
+static void emit_2bytes (my_destination_mgr *destination, int value) /* Emit a 2-byte integer; these are always MSB first in JPEG files */ {
+  emit_byte(destination, (value >> 8) & 0xFF);
+  emit_byte(destination, value & 0xFF);
+}
+
+
+/*
+ * Routines to write specific marker types.
+ */
+
+int emit_dqt (my_destination_mgr *destination, int index)
+/* Emit a DQT marker */
+/* Returns the precision used (0 = 8bits, 1 = 16bits) for baseline checking */
+{
+  /* Quantization table is externally globally defined */
+  extern JQUANT_TBL qtbl;
+  int prec;
+  int i;
+
+  if (qtbl.quantval == NULL) {
+    perror("Quantization table 0x%%02x was not defined");
+    exit(1);
+    /*ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, index);*/
+  }
+  prec = 0;
+  for (i = 0; i < DCTSIZE2; i++) {
+    if (qtbl.quantval[i] > 255)
+      prec = 1;
+  }
+
+  if (! qtbl.sent_table) {
+    emit_marker(destination, M_DQT);
+
+    emit_2bytes(destination, prec ? DCTSIZE2*2 + 1 + 2 : DCTSIZE2 + 1 + 2);
+
+    emit_byte(destination, index + (prec<<4));
+
+    for (i = 0; i < DCTSIZE2; i++) {
+      /* The table entries must be emitted in zigzag order. */
+      unsigned int qval = qtbl.quantval[i];
+
+      if (prec) {
+	emit_byte(destination, (int) (qval >> 8));
+      }
+      emit_byte(destination, (int) (qval & 0xFF));
+    }
+
+    qtbl.sent_table = TRUE;
+  }
+  return prec;
+}
+
+
+static void emit_dht (my_destination_mgr *destination, int index, boolean is_ac)
+/* Emit a DHT marker */
+{
+  extern JHUFF_TBL ac_Huffman_Table[];
+  extern JHUFF_TBL dc_Huffman_Table[];
+  JHUFF_TBL *htbl;
+  int length, i;
+  
+  if (is_ac) {
+    htbl = ac_Huffman_Table;
+    index += 0x10;		/* output index has AC bit set */
+  } else {
+    htbl = dc_Huffman_Table;
+  }
+
+  if (htbl == NULL){
+    perror("Huffman table 0x%%02x was not defined");
+    exit(1);
+    /*ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, index);*/
+  }
+  if (! htbl->sent_table) {
+    emit_marker(destination, M_DHT);
+    
+    length = 0;
+    for (i = 1; i <= 16; i++)
+      length += htbl->bits[i];
+    
+    emit_2bytes(destination, length + 2 + 1 + 16);
+    emit_byte(destination, index);
+    
+    for (i = 1; i <= 16; i++)
+      emit_byte(destination, htbl->bits[i]);
+    
+    for (i = 0; i < length; i++)
+      emit_byte(destination, htbl->huffval[i]);
+    
+    htbl->sent_table = TRUE;
+  }
+}
+
+
+#if 0
+static void emit_dac (j_compress_ptr cinfo)
+/* Emit a DAC marker */
+/* Since the useful info is so small, we want to emit all the tables in */
+/* one DAC marker.  Therefore this routine does its own scan of the table. */
+{
+#ifdef C_ARITH_CODING_SUPPORTED
+  char dc_in_use[NUM_ARITH_TBLS];
+  char ac_in_use[NUM_ARITH_TBLS];
+  int length, i;
+  jpeg_component_info *compptr;
+  
+  for (i = 0; i < NUM_ARITH_TBLS; i++)
+    dc_in_use[i] = ac_in_use[i] = 0;
+  
+  for (i = 0; i < cinfo->comps_in_scan; i++) {
+    compptr = cinfo->cur_comp_info[i];
+    dc_in_use[compptr->dc_tbl_no] = 1;
+    ac_in_use[compptr->ac_tbl_no] = 1;
+  }
+  
+  length = 0;
+  for (i = 0; i < NUM_ARITH_TBLS; i++)
+    length += dc_in_use[i] + ac_in_use[i];
+  
+  emit_marker(cinfo, M_DAC);
+  
+  emit_2bytes(cinfo, length*2 + 2);
+  
+  for (i = 0; i < NUM_ARITH_TBLS; i++) {
+    if (dc_in_use[i]) {
+      emit_byte(cinfo, i);
+      emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4));
+    }
+    if (ac_in_use[i]) {
+      emit_byte(cinfo, i + 0x10);
+      emit_byte(cinfo, cinfo->arith_ac_K[i]);
+    }
+  }
+#endif /* C_ARITH_CODING_SUPPORTED */
+}
+
+
+static void emit_dri (j_compress_ptr cinfo)
+/* Emit a DRI marker */
+{
+  emit_marker(cinfo, M_DRI);
+  
+  emit_2bytes(cinfo, 4);	/* fixed length */
+
+  emit_2bytes(cinfo, (int) cinfo->restart_interval);
+}
+#endif
+
+static void emit_sof(my_destination_mgr *destination, JPEG_MARKER code, int image_height, int image_width)
+/* Emit a SOF marker */
+{
+  int ci;
+  int num_components = 1;
+  jpeg_component_info *compptr;
+  
+  emit_marker(destination, code);
+  
+  emit_2bytes(destination, 3 * num_components + 2 + 5 + 1); /* length */
+
+  /* Make sure image isn't bigger than SOF field can handle */
+  if ((long) image_height > 65535L ||
+      (long) image_width > 65535L) {
+   perror("Maximum supported image dimension is %u pixels");
+  exit(1);
+    /*ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) 65535);*/
+      }
+  emit_byte(destination, 8);
+  emit_2bytes(destination, image_height);
+  emit_2bytes(destination, image_width);
+
+  emit_byte(destination, num_components);
+
+  emit_byte(destination, 1);
+  emit_byte(destination, 0x22);
+  emit_byte(destination, 0);
+/*
+  for (ci = 0, compptr = cinfo->comp_info; ci < num_components; ci++, compptr++) {
+    emit_byte(destination, compptr->component_id);
+    emit_byte(destination, (compptr->h_samp_factor << 4) + compptr->v_samp_factor);
+    emit_byte(destination, compptr->quant_tbl_no);
+  }
+  */
+}
+
+static void emit_sos (my_destination_mgr *destination)
+/* Emit a SOS marker */
+{
+  int i, td, ta, comps_in_scan;
+  comps_in_scan = 1;
+  
+  emit_marker(destination, M_SOS);
+  
+  emit_2bytes(destination, 2 * comps_in_scan + 2 + 1 + 3); /* length */
+  
+  emit_byte(destination, comps_in_scan);
+  
+  for (i = 0; i < comps_in_scan; i++) {
+   /* compptr = cinfo->cur_comp_info[i];*/
+    emit_byte(destination, 1);
+#if 0
+    td = compptr->dc_tbl_no;
+    ta = compptr->ac_tbl_no;
+    if (cinfo->progressive_mode) {
+      /* Progressive mode: only DC or only AC tables are used in one scan;
+       * furthermore, Huffman coding of DC refinement uses no table at all.
+       * We emit 0 for unused field(s); this is recommended by the P&M text
+       * but does not seem to be specified in the standard.
+       */
+      if (cinfo->Ss == 0) {
+	ta = 0;			/* DC scan */
+	if (cinfo->Ah != 0 && !cinfo->arith_code)
+	  td = 0;		/* no DC table either */
+      } else {
+	td = 0;			/* AC scan */
+      }
+    }
+    emit_byte(cinfo, (td << 4) + ta);
+#endif
+    emit_byte(destination, 0);
+  }
+
+#if 0
+  emit_byte(cinfo, cinfo->Ss);
+  emit_byte(cinfo, cinfo->Se);
+  emit_byte(cinfo, (cinfo->Ah << 4) + cinfo->Al);
+#endif
+  emit_byte(destination, 0);
+  emit_byte(destination, 63);
+  emit_byte(destination, 0);
+}
+
+
+static void emit_jfif_app0 (my_destination_mgr *destination)
+/* Emit a JFIF-compliant APP0 marker */
+{
+  /*
+   * Length of APP0 block	(2 bytes)
+   * Block ID			(4 bytes - ASCII "JFIF")
+   * Zero byte			(1 byte to terminate the ID string)
+   * Version Major, Minor	(2 bytes - major first)
+   * Units			(1 byte - 0x00 = none, 0x01 = inch, 0x02 = cm)
+   * Xdpu			(2 bytes - dots per unit horizontal)
+   * Ydpu			(2 bytes - dots per unit vertical)
+   * Thumbnail X size		(1 byte)
+   * Thumbnail Y size		(1 byte)
+   */
+  
+  emit_marker(destination, M_APP0);
+  
+  emit_2bytes(destination, 2 + 4 + 1 + 2 + 1 + 2 + 2 + 1 + 1); /* length */
+
+  emit_byte(destination, 0x4A);	/* Identifier: ASCII "JFIF" */
+  emit_byte(destination, 0x46);
+  emit_byte(destination, 0x49);
+  emit_byte(destination, 0x46);
+  emit_byte(destination, 0);
+  emit_byte(destination, 1); /*destination->JFIF_major_version); / * Version fields */
+  emit_byte(destination, 1); /* destination->JFIF_minor_version); */
+  emit_byte(destination, 1); /* destination->density_unit); / * Pixel size information */
+  emit_2bytes(destination, 0x48); /* (int) destination->X_density); */
+  emit_2bytes(destination, 0x048); /* (int) destination->Y_density); */
+  emit_byte(destination, 0);		/* No thumbnail image */
+  emit_byte(destination, 0);
+}
+
+
+#if 0
+/*
+ * These routines allow writing an arbitrary marker with parameters.
+ * The only intended use is to emit COM or APPn markers after calling
+ * write_file_header and before calling write_frame_header.
+ * Other uses are not guaranteed to produce desirable results.
+ * Counting the parameter bytes properly is the caller's responsibility.
+ */
+
+static void write_marker_header (j_compress_ptr cinfo, int marker, unsigned int datalen)
+/* Emit an arbitrary marker header */
+{
+  if (datalen > (unsigned int) 65533) {		/* safety check */
+    perror("Bogus marker length");
+    exit(1);
+    /*ERREXIT(cinfo, JERR_BAD_LENGTH);*/
+  }
+  emit_marker(cinfo, (JPEG_MARKER) marker);
+
+  emit_2bytes(cinfo, (int) (datalen + 2));	/* total length */
+}
+
+static void write_marker_byte (j_compress_ptr cinfo, int val)
+/* Emit one byte of marker parameters following write_marker_header */
+{
+  emit_byte(cinfo, val);
+}
+
+#endif
+
+/*
+ * Write datastream header.
+ * This consists of an SOI and optional APPn markers.
+ * We recommend use of the JFIF marker, but not the Adobe marker,
+ * when using YCbCr or grayscale data.  The JFIF marker should NOT
+ * be used for any other JPEG colorspace.  The Adobe marker is helpful
+ * to distinguish RGB, CMYK, and YCCK colorspaces.
+ * Note that an application can write additional header markers after
+ * jpeg_start_compress returns.
+ */
+
+static void write_file_header(my_destination_mgr *destination) {
+
+  emit_marker(destination, M_SOI);	/* first the SOI */
+
+  /* SOI is defined to reset restart interval to 0 */
+
+  emit_jfif_app0(destination);
+}
+
+/*
+ * Write frame header.
+ * This consists of DQT and SOFn markers.
+ * Note that we do not emit the SOF until we have emitted the DQT(s).
+ * This avoids compatibility problems with incorrect implementations that
+ * try to error-check the quant table numbers as soon as they see the SOF.
+ */
+
+static void write_frame_header(my_destination_mgr *destination, int x, int y) {
+  int ci, prec;
+  boolean is_baseline;
+  jpeg_component_info *compptr;
+#if 0 
+  /* Emit DQT for each quantization table.
+   * Note that emit_dqt() suppresses any duplicate tables.
+   */
+  prec = 0;
+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
+       ci++, compptr++) {
+    prec += emit_dqt(cinfo, compptr->quant_tbl_no);
+  }
+  /* now prec is nonzero iff there are any 16-bit quant tables. */
+  
+  /* Check for a non-baseline specification.
+   * Note we assume that Huffman table numbers won't be changed later.
+   */
+  if (cinfo->arith_code || cinfo->progressive_mode ||
+      cinfo->data_precision != 8) {
+    is_baseline = FALSE;
+  } else {
+    is_baseline = TRUE;
+    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
+	 ci++, compptr++) {
+      if (compptr->dc_tbl_no > 1 || compptr->ac_tbl_no > 1)
+	is_baseline = FALSE;
+    }
+    if (prec && is_baseline) {
+      is_baseline = FALSE;
+      /* If it's baseline except for quantizer size, warn the user */
+      printf("Caution: quantization tables are too coarse for baseline JPEG");
+    }
+  }
+
+  /* Emit the proper SOF marker */
+  if (cinfo->arith_code) {
+    emit_sof(cinfo, M_SOF9);	/* SOF code for arithmetic coding */
+  } else {
+    if (cinfo->progressive_mode)
+      emit_sof(cinfo, M_SOF2);	/* SOF code for progressive Huffman */
+    else if (is_baseline)
+      emit_sof(cinfo, M_SOF0);	/* SOF code for baseline implementation */
+    else
+      emit_sof(cinfo, M_SOF1);	/* SOF code for non-baseline Huffman file */
+  }
+#endif
+  emit_dqt(destination, 0);
+  emit_sof(destination, M_SOF0, x, y);
+}
+
+
+/*
+ * Write scan header.
+ * This consists of DHT or DAC markers, optional DRI, and SOS.
+ * Compressed data will be written following the SOS.
+ */
+
+static void write_scan_header(my_destination_mgr *destination)
+{
+  int i;
+  int comps_in_scan = 1;
+
+	  
+    /* Emit Huffman tables.
+     * Note that emit_dht() suppresses any duplicate tables.
+     */
+    for (i = 0; i < comps_in_scan; i++) {
+#if 0
+      if (cinfo->progressive_mode) {
+	/* Progressive mode: only DC or only AC tables are used in one scan */
+	if (cinfo->Ss == 0) {
+	  if (cinfo->Ah == 0)	/* DC needs no table for refinement scan */
+	    emit_dht(cinfo, compptr->dc_tbl_no, FALSE);
+	} else {
+	  emit_dht(cinfo, compptr->ac_tbl_no, TRUE);
+	}
+      } else {
+	/* Sequential mode: need both DC and AC tables */
+	emit_dht(cinfo, compptr->dc_tbl_no, FALSE);
+	emit_dht(cinfo, compptr->ac_tbl_no, TRUE);
+      }
+#endif 
+      emit_dht(destination, 0, FALSE);
+      emit_dht(destination, 1, TRUE);
+    }
+
+  emit_sos(destination);
+}
+
+/*
+ * Write datastream trailer.
+ */
+
+static void write_file_trailer(my_destination_mgr *destination) {
+  emit_marker(destination, M_EOI);
+}
+
+#if 0
+/*
+ * Write an abbreviated table-specification datastream.
+ * This consists of SOI, DQT and DHT tables, and EOI.
+ * Any table that is defined and not marked sent_table = TRUE will be
+ * emitted.  Note that all tables will be marked sent_table = TRUE at exit.
+ */
+
+static void write_tables_only (j_compress_ptr cinfo)
+{
+  int i;
+
+  emit_marker(cinfo, M_SOI);
+
+  for (i = 0; i < NUM_QUANT_TBLS; i++) {
+    if (cinfo->quant_tbl_ptrs[i] != NULL)
+      (void) emit_dqt(cinfo, i);
+  }
+
+  if (! cinfo->arith_code) {
+    for (i = 0; i < NUM_HUFF_TBLS; i++) {
+      if (cinfo->dc_huff_tbl_ptrs[i] != NULL)
+	emit_dht(cinfo, i, FALSE);
+      if (cinfo->ac_huff_tbl_ptrs[i] != NULL)
+	emit_dht(cinfo, i, TRUE);
+    }
+  }
+
+  emit_marker(cinfo, M_EOI);
+}
+
+
+/*
+ * Initialize the marker writer module.
+ */
+#if 0
+void jinit_marker_writer (j_compress_ptr cinfo) {
+  my_marker_ptr marker;
+
+  /* Create the subobject */
+  marker = (my_marker_ptr)
+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+				SIZEOF(my_marker_writer));
+  cinfo->marker = (struct jpeg_marker_writer *) marker;
+  /* Initialize method pointers */
+  marker->pub.write_file_header = write_file_header;
+  marker->pub.write_frame_header = write_frame_header;
+  marker->pub.write_scan_header = write_scan_header;
+  marker->pub.write_file_trailer = write_file_trailer;
+  marker->pub.write_tables_only = write_tables_only;
+  marker->pub.write_marker_header = write_marker_header;
+  marker->pub.write_marker_byte = write_marker_byte;
+  /* Initialize private state */
+  marker->last_restart_interval = 0;
+}
+#endif
+
+int main(void) {
+	int retval;
+	my_destination_mgr destination;
+	size_t datacount;
+
+	retval = 0;
+
+	/* Initialize destination structure */
+	destination.pub.next_output_byte = destination.buffer;
+	destination.pub.free_in_buffer = OUTPUT_BUF_SIZE;
+	destination.outfile = fopen("outfile.jpg", "w+");
+
+	/* do something usefull here */
+	printf("Output\n");
+	write_file_header(&destination);
+	write_frame_header(&destination, 640, 480);
+	write_scan_header(&destination);
+	/* write image here */
+	emit_byte(&destination, 0xa6);
+	emit_byte(&destination, 0x17);
+	emit_byte(&destination, 0x11);
+	emit_byte(&destination, 0x83);
+	emit_byte(&destination, 0xff);
+	emit_byte(&destination, 0x0);
+	emit_byte(&destination, 0x4c);
+	emit_byte(&destination, 0x43);
+	emit_byte(&destination, 0x7f);
+	emit_byte(&destination, 0xe4);
+	emit_byte(&destination, 0xce);
+	emit_byte(&destination, 0x6b);
+
+	/* finish up */
+	write_file_trailer(&destination);
+
+	/* Terminate destination structure */
+	datacount = OUTPUT_BUF_SIZE - destination.pub.free_in_buffer;
+	if (datacount > 0) {
+		if (fwrite(destination.buffer, 1, datacount, destination.outfile) != datacount) {
+			perror("Output file write error --- out of disk space?");
+			exit(1);
+		}
+	}
+	fflush(destination.outfile);
+	if (ferror(destination.outfile)) {
+		perror("Output file write error --- out of disk space?");
+		exit(1);
+	}
+	fclose(destination.outfile);
+
+	return retval;
+}
+#endif