/*

* jcmarker.c

*

* Copyright (C) 1991-1998, Thomas G. Lane.

* Modified 2003-2019 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_JPG8 = 0xf8,

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_lse_ict (j_compress_ptr cinfo)

/* Emit an LSE inverse color transform specification marker */

{

/* Support only 1 transform */

if (cinfo->color_transform != JCT_SUBTRACT_GREEN ||

cinfo->num_components < 3)

ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);

emit_marker(cinfo, M_JPG8);

emit_2bytes(cinfo, 24); /* fixed length */

emit_byte(cinfo, 0x0D); /* ID inverse transform specification */

emit_2bytes(cinfo, MAXJSAMPLE); /* MAXTRANS */

emit_byte(cinfo, 3); /* Nt=3 */

emit_byte(cinfo, cinfo->comp_info[1].component_id);

emit_byte(cinfo, cinfo->comp_info[0].component_id);

emit_byte(cinfo, cinfo->comp_info[2].component_id);

emit_byte(cinfo, 0x80); /* F1: CENTER1=1, NORM1=0 */

emit_2bytes(cinfo, 0); /* A(1,1)=0 */

emit_2bytes(cinfo, 0); /* A(1,2)=0 */

emit_byte(cinfo, 0); /* F2: CENTER2=0, NORM2=0 */

emit_2bytes(cinfo, 1); /* A(2,1)=1 */

emit_2bytes(cinfo, 0); /* A(2,2)=0 */

emit_byte(cinfo, 0); /* F3: CENTER3=0, NORM3=0 */

emit_2bytes(cinfo, 1); /* A(3,1)=1 */

emit_2bytes(cinfo, 0); /* A(3,2)=0 */

}

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 */

}

}

/*

* 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 is also used

* for other standard JPEG colorspaces. 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,

* a conditional LSE marker 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 LSE inverse color transform specification marker */

if (cinfo->color_transform)

emit_lse_ict(cinfo);

/* 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 = &marker->pub;

/* 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;

}