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authorJörg Frings-Fürst <debian@jff-webhosting.net>2015-11-06 05:38:49 +0100
committerJörg Frings-Fürst <debian@jff-webhosting.net>2015-11-06 05:38:49 +0100
commit9491825ddff7a294d1f49061bae7044e426aeb2e (patch)
tree06e651099f87140ec534ae47fb8ce1ac6ec7976d /jpeg/jcmarker.c
parentfa756339d4204bff7f2820067f58214d32780d17 (diff)
Imported Upstream version 1.8.3
Diffstat (limited to 'jpeg/jcmarker.c')
-rwxr-xr-xjpeg/jcmarker.c682
1 files changed, 682 insertions, 0 deletions
diff --git a/jpeg/jcmarker.c b/jpeg/jcmarker.c
new file mode 100755
index 0000000..606c19a
--- /dev/null
+++ b/jpeg/jcmarker.c
@@ -0,0 +1,682 @@
+/*
+ * jcmarker.c
+ *
+ * Copyright (C) 1991-1998, Thomas G. Lane.
+ * Modified 2003-2010 by Guido Vollbeding.
+ * 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.
+ */
+
+#define JPEG_INTERNALS
+#include "jinclude.h"
+#include "jpeglib.h"
+
+
+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;
+
+
+/* Private state */
+
+typedef struct {
+ struct jpeg_marker_writer pub; /* public fields */
+
+ unsigned int last_restart_interval; /* last DRI value emitted; 0 after SOI */
+} my_marker_writer;
+
+typedef my_marker_writer * my_marker_ptr;
+
+
+/*
+ * 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.
+ */
+
+LOCAL(void)
+emit_byte (j_compress_ptr cinfo, int val)
+/* Emit a byte */
+{
+ struct jpeg_destination_mgr * dest = cinfo->dest;
+
+ *(dest->next_output_byte)++ = (JOCTET) val;
+ if (--dest->free_in_buffer == 0) {
+ if (! (*dest->empty_output_buffer) (cinfo))
+ ERREXIT(cinfo, JERR_CANT_SUSPEND);
+ }
+}
+
+
+LOCAL(void)
+emit_marker (j_compress_ptr cinfo, JPEG_MARKER mark)
+/* Emit a marker code */
+{
+ emit_byte(cinfo, 0xFF);
+ emit_byte(cinfo, (int) mark);
+}
+
+
+LOCAL(void)
+emit_2bytes (j_compress_ptr cinfo, int value)
+/* Emit a 2-byte integer; these are always MSB first in JPEG files */
+{
+ emit_byte(cinfo, (value >> 8) & 0xFF);
+ emit_byte(cinfo, value & 0xFF);
+}
+
+
+/*
+ * Routines to write specific marker types.
+ */
+
+LOCAL(int)
+emit_dqt (j_compress_ptr cinfo, int index)
+/* Emit a DQT marker */
+/* Returns the precision used (0 = 8bits, 1 = 16bits) for baseline checking */
+{
+ JQUANT_TBL * qtbl = cinfo->quant_tbl_ptrs[index];
+ int prec;
+ int i;
+
+ if (qtbl == NULL)
+ ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, index);
+
+ prec = 0;
+ for (i = 0; i <= cinfo->lim_Se; i++) {
+ if (qtbl->quantval[cinfo->natural_order[i]] > 255)
+ prec = 1;
+ }
+
+ if (! qtbl->sent_table) {
+ emit_marker(cinfo, M_DQT);
+
+ emit_2bytes(cinfo,
+ prec ? cinfo->lim_Se * 2 + 2 + 1 + 2 : cinfo->lim_Se + 1 + 1 + 2);
+
+ emit_byte(cinfo, index + (prec<<4));
+
+ for (i = 0; i <= cinfo->lim_Se; i++) {
+ /* The table entries must be emitted in zigzag order. */
+ unsigned int qval = qtbl->quantval[cinfo->natural_order[i]];
+ if (prec)
+ emit_byte(cinfo, (int) (qval >> 8));
+ emit_byte(cinfo, (int) (qval & 0xFF));
+ }
+
+ qtbl->sent_table = TRUE;
+ }
+
+ return prec;
+}
+
+
+LOCAL(void)
+emit_dht (j_compress_ptr cinfo, int index, boolean is_ac)
+/* Emit a DHT marker */
+{
+ JHUFF_TBL * htbl;
+ int length, i;
+
+ if (is_ac) {
+ htbl = cinfo->ac_huff_tbl_ptrs[index];
+ index += 0x10; /* output index has AC bit set */
+ } else {
+ htbl = cinfo->dc_huff_tbl_ptrs[index];
+ }
+
+ if (htbl == NULL)
+ ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, index);
+
+ if (! htbl->sent_table) {
+ emit_marker(cinfo, M_DHT);
+
+ length = 0;
+ for (i = 1; i <= 16; i++)
+ length += htbl->bits[i];
+
+ emit_2bytes(cinfo, length + 2 + 1 + 16);
+ emit_byte(cinfo, index);
+
+ for (i = 1; i <= 16; i++)
+ emit_byte(cinfo, htbl->bits[i]);
+
+ for (i = 0; i < length; i++)
+ emit_byte(cinfo, htbl->huffval[i]);
+
+ htbl->sent_table = TRUE;
+ }
+}
+
+
+LOCAL(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 needs no table for refinement scan */
+ if (cinfo->Ss == 0 && cinfo->Ah == 0)
+ dc_in_use[compptr->dc_tbl_no] = 1;
+ /* AC needs no table when not present */
+ if (cinfo->Se)
+ 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];
+
+ if (length) {
+ 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 */
+}
+
+
+LOCAL(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);
+}
+
+
+LOCAL(void)
+emit_sof (j_compress_ptr cinfo, JPEG_MARKER code)
+/* Emit a SOF marker */
+{
+ int ci;
+ jpeg_component_info *compptr;
+
+ emit_marker(cinfo, code);
+
+ emit_2bytes(cinfo, 3 * cinfo->num_components + 2 + 5 + 1); /* length */
+
+ /* Make sure image isn't bigger than SOF field can handle */
+ if ((long) cinfo->jpeg_height > 65535L ||
+ (long) cinfo->jpeg_width > 65535L)
+ ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) 65535);
+
+ emit_byte(cinfo, cinfo->data_precision);
+ emit_2bytes(cinfo, (int) cinfo->jpeg_height);
+ emit_2bytes(cinfo, (int) cinfo->jpeg_width);
+
+ emit_byte(cinfo, cinfo->num_components);
+
+ for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
+ ci++, compptr++) {
+ emit_byte(cinfo, compptr->component_id);
+ emit_byte(cinfo, (compptr->h_samp_factor << 4) + compptr->v_samp_factor);
+ emit_byte(cinfo, compptr->quant_tbl_no);
+ }
+}
+
+
+LOCAL(void)
+emit_sos (j_compress_ptr cinfo)
+/* Emit a SOS marker */
+{
+ int i, td, ta;
+ jpeg_component_info *compptr;
+
+ emit_marker(cinfo, M_SOS);
+
+ emit_2bytes(cinfo, 2 * cinfo->comps_in_scan + 2 + 1 + 3); /* length */
+
+ emit_byte(cinfo, cinfo->comps_in_scan);
+
+ for (i = 0; i < cinfo->comps_in_scan; i++) {
+ compptr = cinfo->cur_comp_info[i];
+ emit_byte(cinfo, compptr->component_id);
+
+ /* 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.
+ */
+
+ /* DC needs no table for refinement scan */
+ td = cinfo->Ss == 0 && cinfo->Ah == 0 ? compptr->dc_tbl_no : 0;
+ /* AC needs no table when not present */
+ ta = cinfo->Se ? compptr->ac_tbl_no : 0;
+
+ emit_byte(cinfo, (td << 4) + ta);
+ }
+
+ emit_byte(cinfo, cinfo->Ss);
+ emit_byte(cinfo, cinfo->Se);
+ emit_byte(cinfo, (cinfo->Ah << 4) + cinfo->Al);
+}
+
+
+LOCAL(void)
+emit_pseudo_sos (j_compress_ptr cinfo)
+/* Emit a pseudo SOS marker */
+{
+ emit_marker(cinfo, M_SOS);
+
+ emit_2bytes(cinfo, 2 + 1 + 3); /* length */
+
+ emit_byte(cinfo, 0); /* Ns */
+
+ emit_byte(cinfo, 0); /* Ss */
+ emit_byte(cinfo, cinfo->block_size * cinfo->block_size - 1); /* Se */
+ emit_byte(cinfo, 0); /* Ah/Al */
+}
+
+
+LOCAL(void)
+emit_jfif_app0 (j_compress_ptr cinfo)
+/* 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(cinfo, M_APP0);
+
+ emit_2bytes(cinfo, 2 + 4 + 1 + 2 + 1 + 2 + 2 + 1 + 1); /* length */
+
+ emit_byte(cinfo, 0x4A); /* Identifier: ASCII "JFIF" */
+ emit_byte(cinfo, 0x46);
+ emit_byte(cinfo, 0x49);
+ emit_byte(cinfo, 0x46);
+ emit_byte(cinfo, 0);
+ emit_byte(cinfo, cinfo->JFIF_major_version); /* Version fields */
+ emit_byte(cinfo, cinfo->JFIF_minor_version);
+ emit_byte(cinfo, cinfo->density_unit); /* Pixel size information */
+ emit_2bytes(cinfo, (int) cinfo->X_density);
+ emit_2bytes(cinfo, (int) cinfo->Y_density);
+ emit_byte(cinfo, 0); /* No thumbnail image */
+ emit_byte(cinfo, 0);
+}
+
+
+LOCAL(void)
+emit_adobe_app14 (j_compress_ptr cinfo)
+/* Emit an Adobe APP14 marker */
+{
+ /*
+ * Length of APP14 block (2 bytes)
+ * Block ID (5 bytes - ASCII "Adobe")
+ * Version Number (2 bytes - currently 100)
+ * Flags0 (2 bytes - currently 0)
+ * Flags1 (2 bytes - currently 0)
+ * Color transform (1 byte)
+ *
+ * Although Adobe TN 5116 mentions Version = 101, all the Adobe files
+ * now in circulation seem to use Version = 100, so that's what we write.
+ *
+ * We write the color transform byte as 1 if the JPEG color space is
+ * YCbCr, 2 if it's YCCK, 0 otherwise. Adobe's definition has to do with
+ * whether the encoder performed a transformation, which is pretty useless.
+ */
+
+ emit_marker(cinfo, M_APP14);
+
+ emit_2bytes(cinfo, 2 + 5 + 2 + 2 + 2 + 1); /* length */
+
+ emit_byte(cinfo, 0x41); /* Identifier: ASCII "Adobe" */
+ emit_byte(cinfo, 0x64);
+ emit_byte(cinfo, 0x6F);
+ emit_byte(cinfo, 0x62);
+ emit_byte(cinfo, 0x65);
+ emit_2bytes(cinfo, 100); /* Version */
+ emit_2bytes(cinfo, 0); /* Flags0 */
+ emit_2bytes(cinfo, 0); /* Flags1 */
+ switch (cinfo->jpeg_color_space) {
+ case JCS_YCbCr:
+ emit_byte(cinfo, 1); /* Color transform = 1 */
+ break;
+ case JCS_YCCK:
+ emit_byte(cinfo, 2); /* Color transform = 2 */
+ break;
+ default:
+ emit_byte(cinfo, 0); /* Color transform = 0 */
+ break;
+ }
+}
+
+
+/*
+ * 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.
+ */
+
+METHODDEF(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 */
+ ERREXIT(cinfo, JERR_BAD_LENGTH);
+
+ emit_marker(cinfo, (JPEG_MARKER) marker);
+
+ emit_2bytes(cinfo, (int) (datalen + 2)); /* total length */
+}
+
+METHODDEF(void)
+write_marker_byte (j_compress_ptr cinfo, int val)
+/* Emit one byte of marker parameters following write_marker_header */
+{
+ emit_byte(cinfo, val);
+}
+
+
+/*
+ * 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.
+ */
+
+METHODDEF(void)
+write_file_header (j_compress_ptr cinfo)
+{
+ my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
+
+ emit_marker(cinfo, M_SOI); /* first the SOI */
+
+ /* SOI is defined to reset restart interval to 0 */
+ marker->last_restart_interval = 0;
+
+ if (cinfo->write_JFIF_header) /* next an optional JFIF APP0 */
+ emit_jfif_app0(cinfo);
+ if (cinfo->write_Adobe_marker) /* next an optional Adobe APP14 */
+ emit_adobe_app14(cinfo);
+}
+
+
+/*
+ * Write frame header.
+ * This consists of DQT and SOFn markers, and a conditional pseudo SOS marker.
+ * 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.
+ */
+
+METHODDEF(void)
+write_frame_header (j_compress_ptr cinfo)
+{
+ int ci, prec;
+ boolean is_baseline;
+ jpeg_component_info *compptr;
+
+ /* 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 || cinfo->block_size != DCTSIZE) {
+ 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 */
+ TRACEMS(cinfo, 0, JTRC_16BIT_TABLES);
+ }
+ }
+
+ /* Emit the proper SOF marker */
+ if (cinfo->arith_code) {
+ if (cinfo->progressive_mode)
+ emit_sof(cinfo, M_SOF10); /* SOF code for progressive arithmetic */
+ else
+ emit_sof(cinfo, M_SOF9); /* SOF code for sequential arithmetic */
+ } 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 */
+ }
+
+ /* Check to emit pseudo SOS marker */
+ if (cinfo->progressive_mode && cinfo->block_size != DCTSIZE)
+ emit_pseudo_sos(cinfo);
+}
+
+
+/*
+ * Write scan header.
+ * This consists of DHT or DAC markers, optional DRI, and SOS.
+ * Compressed data will be written following the SOS.
+ */
+
+METHODDEF(void)
+write_scan_header (j_compress_ptr cinfo)
+{
+ my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
+ int i;
+ jpeg_component_info *compptr;
+
+ if (cinfo->arith_code) {
+ /* Emit arith conditioning info. We may have some duplication
+ * if the file has multiple scans, but it's so small it's hardly
+ * worth worrying about.
+ */
+ emit_dac(cinfo);
+ } else {
+ /* Emit Huffman tables.
+ * Note that emit_dht() suppresses any duplicate tables.
+ */
+ for (i = 0; i < cinfo->comps_in_scan; i++) {
+ compptr = cinfo->cur_comp_info[i];
+ /* DC needs no table for refinement scan */
+ if (cinfo->Ss == 0 && cinfo->Ah == 0)
+ emit_dht(cinfo, compptr->dc_tbl_no, FALSE);
+ /* AC needs no table when not present */
+ if (cinfo->Se)
+ emit_dht(cinfo, compptr->ac_tbl_no, TRUE);
+ }
+ }
+
+ /* Emit DRI if required --- note that DRI value could change for each scan.
+ * We avoid wasting space with unnecessary DRIs, however.
+ */
+ if (cinfo->restart_interval != marker->last_restart_interval) {
+ emit_dri(cinfo);
+ marker->last_restart_interval = cinfo->restart_interval;
+ }
+
+ emit_sos(cinfo);
+}
+
+
+/*
+ * Write datastream trailer.
+ */
+
+METHODDEF(void)
+write_file_trailer (j_compress_ptr cinfo)
+{
+ emit_marker(cinfo, M_EOI);
+}
+
+
+/*
+ * 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.
+ */
+
+METHODDEF(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.
+ */
+
+GLOBAL(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;
+}