nuclear@2: /*
nuclear@2:  * jcmarker.c
nuclear@2:  *
nuclear@2:  * Copyright (C) 1991-1998, Thomas G. Lane.
nuclear@2:  * This file is part of the Independent JPEG Group's software.
nuclear@2:  * For conditions of distribution and use, see the accompanying README file.
nuclear@2:  *
nuclear@2:  * This file contains routines to write JPEG datastream markers.
nuclear@2:  */
nuclear@2: 
nuclear@2: #define JPEG_INTERNALS
nuclear@2: #include "jinclude.h"
nuclear@2: #include "jpeglib.h"
nuclear@2: 
nuclear@2: 
nuclear@2: typedef enum {			/* JPEG marker codes */
nuclear@2:   M_SOF0  = 0xc0,
nuclear@2:   M_SOF1  = 0xc1,
nuclear@2:   M_SOF2  = 0xc2,
nuclear@2:   M_SOF3  = 0xc3,
nuclear@2:   
nuclear@2:   M_SOF5  = 0xc5,
nuclear@2:   M_SOF6  = 0xc6,
nuclear@2:   M_SOF7  = 0xc7,
nuclear@2:   
nuclear@2:   M_JPG   = 0xc8,
nuclear@2:   M_SOF9  = 0xc9,
nuclear@2:   M_SOF10 = 0xca,
nuclear@2:   M_SOF11 = 0xcb,
nuclear@2:   
nuclear@2:   M_SOF13 = 0xcd,
nuclear@2:   M_SOF14 = 0xce,
nuclear@2:   M_SOF15 = 0xcf,
nuclear@2:   
nuclear@2:   M_DHT   = 0xc4,
nuclear@2:   
nuclear@2:   M_DAC   = 0xcc,
nuclear@2:   
nuclear@2:   M_RST0  = 0xd0,
nuclear@2:   M_RST1  = 0xd1,
nuclear@2:   M_RST2  = 0xd2,
nuclear@2:   M_RST3  = 0xd3,
nuclear@2:   M_RST4  = 0xd4,
nuclear@2:   M_RST5  = 0xd5,
nuclear@2:   M_RST6  = 0xd6,
nuclear@2:   M_RST7  = 0xd7,
nuclear@2:   
nuclear@2:   M_SOI   = 0xd8,
nuclear@2:   M_EOI   = 0xd9,
nuclear@2:   M_SOS   = 0xda,
nuclear@2:   M_DQT   = 0xdb,
nuclear@2:   M_DNL   = 0xdc,
nuclear@2:   M_DRI   = 0xdd,
nuclear@2:   M_DHP   = 0xde,
nuclear@2:   M_EXP   = 0xdf,
nuclear@2:   
nuclear@2:   M_APP0  = 0xe0,
nuclear@2:   M_APP1  = 0xe1,
nuclear@2:   M_APP2  = 0xe2,
nuclear@2:   M_APP3  = 0xe3,
nuclear@2:   M_APP4  = 0xe4,
nuclear@2:   M_APP5  = 0xe5,
nuclear@2:   M_APP6  = 0xe6,
nuclear@2:   M_APP7  = 0xe7,
nuclear@2:   M_APP8  = 0xe8,
nuclear@2:   M_APP9  = 0xe9,
nuclear@2:   M_APP10 = 0xea,
nuclear@2:   M_APP11 = 0xeb,
nuclear@2:   M_APP12 = 0xec,
nuclear@2:   M_APP13 = 0xed,
nuclear@2:   M_APP14 = 0xee,
nuclear@2:   M_APP15 = 0xef,
nuclear@2:   
nuclear@2:   M_JPG0  = 0xf0,
nuclear@2:   M_JPG13 = 0xfd,
nuclear@2:   M_COM   = 0xfe,
nuclear@2:   
nuclear@2:   M_TEM   = 0x01,
nuclear@2:   
nuclear@2:   M_ERROR = 0x100
nuclear@2: } JPEG_MARKER;
nuclear@2: 
nuclear@2: 
nuclear@2: /* Private state */
nuclear@2: 
nuclear@2: typedef struct {
nuclear@2:   struct jpeg_marker_writer pub; /* public fields */
nuclear@2: 
nuclear@2:   unsigned int last_restart_interval; /* last DRI value emitted; 0 after SOI */
nuclear@2: } my_marker_writer;
nuclear@2: 
nuclear@2: typedef my_marker_writer * my_marker_ptr;
nuclear@2: 
nuclear@2: 
nuclear@2: /*
nuclear@2:  * Basic output routines.
nuclear@2:  *
nuclear@2:  * Note that we do not support suspension while writing a marker.
nuclear@2:  * Therefore, an application using suspension must ensure that there is
nuclear@2:  * enough buffer space for the initial markers (typ. 600-700 bytes) before
nuclear@2:  * calling jpeg_start_compress, and enough space to write the trailing EOI
nuclear@2:  * (a few bytes) before calling jpeg_finish_compress.  Multipass compression
nuclear@2:  * modes are not supported at all with suspension, so those two are the only
nuclear@2:  * points where markers will be written.
nuclear@2:  */
nuclear@2: 
nuclear@2: LOCAL(void)
nuclear@2: emit_byte (j_compress_ptr cinfo, int val)
nuclear@2: /* Emit a byte */
nuclear@2: {
nuclear@2:   struct jpeg_destination_mgr * dest = cinfo->dest;
nuclear@2: 
nuclear@2:   *(dest->next_output_byte)++ = (JOCTET) val;
nuclear@2:   if (--dest->free_in_buffer == 0) {
nuclear@2:     if (! (*dest->empty_output_buffer) (cinfo))
nuclear@2:       ERREXIT(cinfo, JERR_CANT_SUSPEND);
nuclear@2:   }
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: LOCAL(void)
nuclear@2: emit_marker (j_compress_ptr cinfo, JPEG_MARKER mark)
nuclear@2: /* Emit a marker code */
nuclear@2: {
nuclear@2:   emit_byte(cinfo, 0xFF);
nuclear@2:   emit_byte(cinfo, (int) mark);
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: LOCAL(void)
nuclear@2: emit_2bytes (j_compress_ptr cinfo, int value)
nuclear@2: /* Emit a 2-byte integer; these are always MSB first in JPEG files */
nuclear@2: {
nuclear@2:   emit_byte(cinfo, (value >> 8) & 0xFF);
nuclear@2:   emit_byte(cinfo, value & 0xFF);
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: /*
nuclear@2:  * Routines to write specific marker types.
nuclear@2:  */
nuclear@2: 
nuclear@2: LOCAL(int)
nuclear@2: emit_dqt (j_compress_ptr cinfo, int index)
nuclear@2: /* Emit a DQT marker */
nuclear@2: /* Returns the precision used (0 = 8bits, 1 = 16bits) for baseline checking */
nuclear@2: {
nuclear@2:   JQUANT_TBL * qtbl = cinfo->quant_tbl_ptrs[index];
nuclear@2:   int prec;
nuclear@2:   int i;
nuclear@2: 
nuclear@2:   if (qtbl == NULL)
nuclear@2:     ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, index);
nuclear@2: 
nuclear@2:   prec = 0;
nuclear@2:   for (i = 0; i < DCTSIZE2; i++) {
nuclear@2:     if (qtbl->quantval[i] > 255)
nuclear@2:       prec = 1;
nuclear@2:   }
nuclear@2: 
nuclear@2:   if (! qtbl->sent_table) {
nuclear@2:     emit_marker(cinfo, M_DQT);
nuclear@2: 
nuclear@2:     emit_2bytes(cinfo, prec ? DCTSIZE2*2 + 1 + 2 : DCTSIZE2 + 1 + 2);
nuclear@2: 
nuclear@2:     emit_byte(cinfo, index + (prec<<4));
nuclear@2: 
nuclear@2:     for (i = 0; i < DCTSIZE2; i++) {
nuclear@2:       /* The table entries must be emitted in zigzag order. */
nuclear@2:       unsigned int qval = qtbl->quantval[jpeg_natural_order[i]];
nuclear@2:       if (prec)
nuclear@2: 	emit_byte(cinfo, (int) (qval >> 8));
nuclear@2:       emit_byte(cinfo, (int) (qval & 0xFF));
nuclear@2:     }
nuclear@2: 
nuclear@2:     qtbl->sent_table = TRUE;
nuclear@2:   }
nuclear@2: 
nuclear@2:   return prec;
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: LOCAL(void)
nuclear@2: emit_dht (j_compress_ptr cinfo, int index, boolean is_ac)
nuclear@2: /* Emit a DHT marker */
nuclear@2: {
nuclear@2:   JHUFF_TBL * htbl;
nuclear@2:   int length, i;
nuclear@2:   
nuclear@2:   if (is_ac) {
nuclear@2:     htbl = cinfo->ac_huff_tbl_ptrs[index];
nuclear@2:     index += 0x10;		/* output index has AC bit set */
nuclear@2:   } else {
nuclear@2:     htbl = cinfo->dc_huff_tbl_ptrs[index];
nuclear@2:   }
nuclear@2: 
nuclear@2:   if (htbl == NULL)
nuclear@2:     ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, index);
nuclear@2:   
nuclear@2:   if (! htbl->sent_table) {
nuclear@2:     emit_marker(cinfo, M_DHT);
nuclear@2:     
nuclear@2:     length = 0;
nuclear@2:     for (i = 1; i <= 16; i++)
nuclear@2:       length += htbl->bits[i];
nuclear@2:     
nuclear@2:     emit_2bytes(cinfo, length + 2 + 1 + 16);
nuclear@2:     emit_byte(cinfo, index);
nuclear@2:     
nuclear@2:     for (i = 1; i <= 16; i++)
nuclear@2:       emit_byte(cinfo, htbl->bits[i]);
nuclear@2:     
nuclear@2:     for (i = 0; i < length; i++)
nuclear@2:       emit_byte(cinfo, htbl->huffval[i]);
nuclear@2:     
nuclear@2:     htbl->sent_table = TRUE;
nuclear@2:   }
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: LOCAL(void)
nuclear@2: emit_dac (j_compress_ptr cinfo)
nuclear@2: /* Emit a DAC marker */
nuclear@2: /* Since the useful info is so small, we want to emit all the tables in */
nuclear@2: /* one DAC marker.  Therefore this routine does its own scan of the table. */
nuclear@2: {
nuclear@2: #ifdef C_ARITH_CODING_SUPPORTED
nuclear@2:   char dc_in_use[NUM_ARITH_TBLS];
nuclear@2:   char ac_in_use[NUM_ARITH_TBLS];
nuclear@2:   int length, i;
nuclear@2:   jpeg_component_info *compptr;
nuclear@2:   
nuclear@2:   for (i = 0; i < NUM_ARITH_TBLS; i++)
nuclear@2:     dc_in_use[i] = ac_in_use[i] = 0;
nuclear@2:   
nuclear@2:   for (i = 0; i < cinfo->comps_in_scan; i++) {
nuclear@2:     compptr = cinfo->cur_comp_info[i];
nuclear@2:     dc_in_use[compptr->dc_tbl_no] = 1;
nuclear@2:     ac_in_use[compptr->ac_tbl_no] = 1;
nuclear@2:   }
nuclear@2:   
nuclear@2:   length = 0;
nuclear@2:   for (i = 0; i < NUM_ARITH_TBLS; i++)
nuclear@2:     length += dc_in_use[i] + ac_in_use[i];
nuclear@2:   
nuclear@2:   emit_marker(cinfo, M_DAC);
nuclear@2:   
nuclear@2:   emit_2bytes(cinfo, length*2 + 2);
nuclear@2:   
nuclear@2:   for (i = 0; i < NUM_ARITH_TBLS; i++) {
nuclear@2:     if (dc_in_use[i]) {
nuclear@2:       emit_byte(cinfo, i);
nuclear@2:       emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4));
nuclear@2:     }
nuclear@2:     if (ac_in_use[i]) {
nuclear@2:       emit_byte(cinfo, i + 0x10);
nuclear@2:       emit_byte(cinfo, cinfo->arith_ac_K[i]);
nuclear@2:     }
nuclear@2:   }
nuclear@2: #endif /* C_ARITH_CODING_SUPPORTED */
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: LOCAL(void)
nuclear@2: emit_dri (j_compress_ptr cinfo)
nuclear@2: /* Emit a DRI marker */
nuclear@2: {
nuclear@2:   emit_marker(cinfo, M_DRI);
nuclear@2:   
nuclear@2:   emit_2bytes(cinfo, 4);	/* fixed length */
nuclear@2: 
nuclear@2:   emit_2bytes(cinfo, (int) cinfo->restart_interval);
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: LOCAL(void)
nuclear@2: emit_sof (j_compress_ptr cinfo, JPEG_MARKER code)
nuclear@2: /* Emit a SOF marker */
nuclear@2: {
nuclear@2:   int ci;
nuclear@2:   jpeg_component_info *compptr;
nuclear@2:   
nuclear@2:   emit_marker(cinfo, code);
nuclear@2:   
nuclear@2:   emit_2bytes(cinfo, 3 * cinfo->num_components + 2 + 5 + 1); /* length */
nuclear@2: 
nuclear@2:   /* Make sure image isn't bigger than SOF field can handle */
nuclear@2:   if ((long) cinfo->image_height > 65535L ||
nuclear@2:       (long) cinfo->image_width > 65535L)
nuclear@2:     ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) 65535);
nuclear@2: 
nuclear@2:   emit_byte(cinfo, cinfo->data_precision);
nuclear@2:   emit_2bytes(cinfo, (int) cinfo->image_height);
nuclear@2:   emit_2bytes(cinfo, (int) cinfo->image_width);
nuclear@2: 
nuclear@2:   emit_byte(cinfo, cinfo->num_components);
nuclear@2: 
nuclear@2:   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
nuclear@2:        ci++, compptr++) {
nuclear@2:     emit_byte(cinfo, compptr->component_id);
nuclear@2:     emit_byte(cinfo, (compptr->h_samp_factor << 4) + compptr->v_samp_factor);
nuclear@2:     emit_byte(cinfo, compptr->quant_tbl_no);
nuclear@2:   }
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: LOCAL(void)
nuclear@2: emit_sos (j_compress_ptr cinfo)
nuclear@2: /* Emit a SOS marker */
nuclear@2: {
nuclear@2:   int i, td, ta;
nuclear@2:   jpeg_component_info *compptr;
nuclear@2:   
nuclear@2:   emit_marker(cinfo, M_SOS);
nuclear@2:   
nuclear@2:   emit_2bytes(cinfo, 2 * cinfo->comps_in_scan + 2 + 1 + 3); /* length */
nuclear@2:   
nuclear@2:   emit_byte(cinfo, cinfo->comps_in_scan);
nuclear@2:   
nuclear@2:   for (i = 0; i < cinfo->comps_in_scan; i++) {
nuclear@2:     compptr = cinfo->cur_comp_info[i];
nuclear@2:     emit_byte(cinfo, compptr->component_id);
nuclear@2:     td = compptr->dc_tbl_no;
nuclear@2:     ta = compptr->ac_tbl_no;
nuclear@2:     if (cinfo->progressive_mode) {
nuclear@2:       /* Progressive mode: only DC or only AC tables are used in one scan;
nuclear@2:        * furthermore, Huffman coding of DC refinement uses no table at all.
nuclear@2:        * We emit 0 for unused field(s); this is recommended by the P&M text
nuclear@2:        * but does not seem to be specified in the standard.
nuclear@2:        */
nuclear@2:       if (cinfo->Ss == 0) {
nuclear@2: 	ta = 0;			/* DC scan */
nuclear@2: 	if (cinfo->Ah != 0 && !cinfo->arith_code)
nuclear@2: 	  td = 0;		/* no DC table either */
nuclear@2:       } else {
nuclear@2: 	td = 0;			/* AC scan */
nuclear@2:       }
nuclear@2:     }
nuclear@2:     emit_byte(cinfo, (td << 4) + ta);
nuclear@2:   }
nuclear@2: 
nuclear@2:   emit_byte(cinfo, cinfo->Ss);
nuclear@2:   emit_byte(cinfo, cinfo->Se);
nuclear@2:   emit_byte(cinfo, (cinfo->Ah << 4) + cinfo->Al);
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: LOCAL(void)
nuclear@2: emit_jfif_app0 (j_compress_ptr cinfo)
nuclear@2: /* Emit a JFIF-compliant APP0 marker */
nuclear@2: {
nuclear@2:   /*
nuclear@2:    * Length of APP0 block	(2 bytes)
nuclear@2:    * Block ID			(4 bytes - ASCII "JFIF")
nuclear@2:    * Zero byte			(1 byte to terminate the ID string)
nuclear@2:    * Version Major, Minor	(2 bytes - major first)
nuclear@2:    * Units			(1 byte - 0x00 = none, 0x01 = inch, 0x02 = cm)
nuclear@2:    * Xdpu			(2 bytes - dots per unit horizontal)
nuclear@2:    * Ydpu			(2 bytes - dots per unit vertical)
nuclear@2:    * Thumbnail X size		(1 byte)
nuclear@2:    * Thumbnail Y size		(1 byte)
nuclear@2:    */
nuclear@2:   
nuclear@2:   emit_marker(cinfo, M_APP0);
nuclear@2:   
nuclear@2:   emit_2bytes(cinfo, 2 + 4 + 1 + 2 + 1 + 2 + 2 + 1 + 1); /* length */
nuclear@2: 
nuclear@2:   emit_byte(cinfo, 0x4A);	/* Identifier: ASCII "JFIF" */
nuclear@2:   emit_byte(cinfo, 0x46);
nuclear@2:   emit_byte(cinfo, 0x49);
nuclear@2:   emit_byte(cinfo, 0x46);
nuclear@2:   emit_byte(cinfo, 0);
nuclear@2:   emit_byte(cinfo, cinfo->JFIF_major_version); /* Version fields */
nuclear@2:   emit_byte(cinfo, cinfo->JFIF_minor_version);
nuclear@2:   emit_byte(cinfo, cinfo->density_unit); /* Pixel size information */
nuclear@2:   emit_2bytes(cinfo, (int) cinfo->X_density);
nuclear@2:   emit_2bytes(cinfo, (int) cinfo->Y_density);
nuclear@2:   emit_byte(cinfo, 0);		/* No thumbnail image */
nuclear@2:   emit_byte(cinfo, 0);
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: LOCAL(void)
nuclear@2: emit_adobe_app14 (j_compress_ptr cinfo)
nuclear@2: /* Emit an Adobe APP14 marker */
nuclear@2: {
nuclear@2:   /*
nuclear@2:    * Length of APP14 block	(2 bytes)
nuclear@2:    * Block ID			(5 bytes - ASCII "Adobe")
nuclear@2:    * Version Number		(2 bytes - currently 100)
nuclear@2:    * Flags0			(2 bytes - currently 0)
nuclear@2:    * Flags1			(2 bytes - currently 0)
nuclear@2:    * Color transform		(1 byte)
nuclear@2:    *
nuclear@2:    * Although Adobe TN 5116 mentions Version = 101, all the Adobe files
nuclear@2:    * now in circulation seem to use Version = 100, so that's what we write.
nuclear@2:    *
nuclear@2:    * We write the color transform byte as 1 if the JPEG color space is
nuclear@2:    * YCbCr, 2 if it's YCCK, 0 otherwise.  Adobe's definition has to do with
nuclear@2:    * whether the encoder performed a transformation, which is pretty useless.
nuclear@2:    */
nuclear@2:   
nuclear@2:   emit_marker(cinfo, M_APP14);
nuclear@2:   
nuclear@2:   emit_2bytes(cinfo, 2 + 5 + 2 + 2 + 2 + 1); /* length */
nuclear@2: 
nuclear@2:   emit_byte(cinfo, 0x41);	/* Identifier: ASCII "Adobe" */
nuclear@2:   emit_byte(cinfo, 0x64);
nuclear@2:   emit_byte(cinfo, 0x6F);
nuclear@2:   emit_byte(cinfo, 0x62);
nuclear@2:   emit_byte(cinfo, 0x65);
nuclear@2:   emit_2bytes(cinfo, 100);	/* Version */
nuclear@2:   emit_2bytes(cinfo, 0);	/* Flags0 */
nuclear@2:   emit_2bytes(cinfo, 0);	/* Flags1 */
nuclear@2:   switch (cinfo->jpeg_color_space) {
nuclear@2:   case JCS_YCbCr:
nuclear@2:     emit_byte(cinfo, 1);	/* Color transform = 1 */
nuclear@2:     break;
nuclear@2:   case JCS_YCCK:
nuclear@2:     emit_byte(cinfo, 2);	/* Color transform = 2 */
nuclear@2:     break;
nuclear@2:   default:
nuclear@2:     emit_byte(cinfo, 0);	/* Color transform = 0 */
nuclear@2:     break;
nuclear@2:   }
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: /*
nuclear@2:  * These routines allow writing an arbitrary marker with parameters.
nuclear@2:  * The only intended use is to emit COM or APPn markers after calling
nuclear@2:  * write_file_header and before calling write_frame_header.
nuclear@2:  * Other uses are not guaranteed to produce desirable results.
nuclear@2:  * Counting the parameter bytes properly is the caller's responsibility.
nuclear@2:  */
nuclear@2: 
nuclear@2: METHODDEF(void)
nuclear@2: write_marker_header (j_compress_ptr cinfo, int marker, unsigned int datalen)
nuclear@2: /* Emit an arbitrary marker header */
nuclear@2: {
nuclear@2:   if (datalen > (unsigned int) 65533)		/* safety check */
nuclear@2:     ERREXIT(cinfo, JERR_BAD_LENGTH);
nuclear@2: 
nuclear@2:   emit_marker(cinfo, (JPEG_MARKER) marker);
nuclear@2: 
nuclear@2:   emit_2bytes(cinfo, (int) (datalen + 2));	/* total length */
nuclear@2: }
nuclear@2: 
nuclear@2: METHODDEF(void)
nuclear@2: write_marker_byte (j_compress_ptr cinfo, int val)
nuclear@2: /* Emit one byte of marker parameters following write_marker_header */
nuclear@2: {
nuclear@2:   emit_byte(cinfo, val);
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: /*
nuclear@2:  * Write datastream header.
nuclear@2:  * This consists of an SOI and optional APPn markers.
nuclear@2:  * We recommend use of the JFIF marker, but not the Adobe marker,
nuclear@2:  * when using YCbCr or grayscale data.  The JFIF marker should NOT
nuclear@2:  * be used for any other JPEG colorspace.  The Adobe marker is helpful
nuclear@2:  * to distinguish RGB, CMYK, and YCCK colorspaces.
nuclear@2:  * Note that an application can write additional header markers after
nuclear@2:  * jpeg_start_compress returns.
nuclear@2:  */
nuclear@2: 
nuclear@2: METHODDEF(void)
nuclear@2: write_file_header (j_compress_ptr cinfo)
nuclear@2: {
nuclear@2:   my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
nuclear@2: 
nuclear@2:   emit_marker(cinfo, M_SOI);	/* first the SOI */
nuclear@2: 
nuclear@2:   /* SOI is defined to reset restart interval to 0 */
nuclear@2:   marker->last_restart_interval = 0;
nuclear@2: 
nuclear@2:   if (cinfo->write_JFIF_header)	/* next an optional JFIF APP0 */
nuclear@2:     emit_jfif_app0(cinfo);
nuclear@2:   if (cinfo->write_Adobe_marker) /* next an optional Adobe APP14 */
nuclear@2:     emit_adobe_app14(cinfo);
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: /*
nuclear@2:  * Write frame header.
nuclear@2:  * This consists of DQT and SOFn markers.
nuclear@2:  * Note that we do not emit the SOF until we have emitted the DQT(s).
nuclear@2:  * This avoids compatibility problems with incorrect implementations that
nuclear@2:  * try to error-check the quant table numbers as soon as they see the SOF.
nuclear@2:  */
nuclear@2: 
nuclear@2: METHODDEF(void)
nuclear@2: write_frame_header (j_compress_ptr cinfo)
nuclear@2: {
nuclear@2:   int ci, prec;
nuclear@2:   boolean is_baseline;
nuclear@2:   jpeg_component_info *compptr;
nuclear@2:   
nuclear@2:   /* Emit DQT for each quantization table.
nuclear@2:    * Note that emit_dqt() suppresses any duplicate tables.
nuclear@2:    */
nuclear@2:   prec = 0;
nuclear@2:   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
nuclear@2:        ci++, compptr++) {
nuclear@2:     prec += emit_dqt(cinfo, compptr->quant_tbl_no);
nuclear@2:   }
nuclear@2:   /* now prec is nonzero iff there are any 16-bit quant tables. */
nuclear@2: 
nuclear@2:   /* Check for a non-baseline specification.
nuclear@2:    * Note we assume that Huffman table numbers won't be changed later.
nuclear@2:    */
nuclear@2:   if (cinfo->arith_code || cinfo->progressive_mode ||
nuclear@2:       cinfo->data_precision != 8) {
nuclear@2:     is_baseline = FALSE;
nuclear@2:   } else {
nuclear@2:     is_baseline = TRUE;
nuclear@2:     for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
nuclear@2: 	 ci++, compptr++) {
nuclear@2:       if (compptr->dc_tbl_no > 1 || compptr->ac_tbl_no > 1)
nuclear@2: 	is_baseline = FALSE;
nuclear@2:     }
nuclear@2:     if (prec && is_baseline) {
nuclear@2:       is_baseline = FALSE;
nuclear@2:       /* If it's baseline except for quantizer size, warn the user */
nuclear@2:       TRACEMS(cinfo, 0, JTRC_16BIT_TABLES);
nuclear@2:     }
nuclear@2:   }
nuclear@2: 
nuclear@2:   /* Emit the proper SOF marker */
nuclear@2:   if (cinfo->arith_code) {
nuclear@2:     emit_sof(cinfo, M_SOF9);	/* SOF code for arithmetic coding */
nuclear@2:   } else {
nuclear@2:     if (cinfo->progressive_mode)
nuclear@2:       emit_sof(cinfo, M_SOF2);	/* SOF code for progressive Huffman */
nuclear@2:     else if (is_baseline)
nuclear@2:       emit_sof(cinfo, M_SOF0);	/* SOF code for baseline implementation */
nuclear@2:     else
nuclear@2:       emit_sof(cinfo, M_SOF1);	/* SOF code for non-baseline Huffman file */
nuclear@2:   }
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: /*
nuclear@2:  * Write scan header.
nuclear@2:  * This consists of DHT or DAC markers, optional DRI, and SOS.
nuclear@2:  * Compressed data will be written following the SOS.
nuclear@2:  */
nuclear@2: 
nuclear@2: METHODDEF(void)
nuclear@2: write_scan_header (j_compress_ptr cinfo)
nuclear@2: {
nuclear@2:   my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
nuclear@2:   int i;
nuclear@2:   jpeg_component_info *compptr;
nuclear@2: 
nuclear@2:   if (cinfo->arith_code) {
nuclear@2:     /* Emit arith conditioning info.  We may have some duplication
nuclear@2:      * if the file has multiple scans, but it's so small it's hardly
nuclear@2:      * worth worrying about.
nuclear@2:      */
nuclear@2:     emit_dac(cinfo);
nuclear@2:   } else {
nuclear@2:     /* Emit Huffman tables.
nuclear@2:      * Note that emit_dht() suppresses any duplicate tables.
nuclear@2:      */
nuclear@2:     for (i = 0; i < cinfo->comps_in_scan; i++) {
nuclear@2:       compptr = cinfo->cur_comp_info[i];
nuclear@2:       if (cinfo->progressive_mode) {
nuclear@2: 	/* Progressive mode: only DC or only AC tables are used in one scan */
nuclear@2: 	if (cinfo->Ss == 0) {
nuclear@2: 	  if (cinfo->Ah == 0)	/* DC needs no table for refinement scan */
nuclear@2: 	    emit_dht(cinfo, compptr->dc_tbl_no, FALSE);
nuclear@2: 	} else {
nuclear@2: 	  emit_dht(cinfo, compptr->ac_tbl_no, TRUE);
nuclear@2: 	}
nuclear@2:       } else {
nuclear@2: 	/* Sequential mode: need both DC and AC tables */
nuclear@2: 	emit_dht(cinfo, compptr->dc_tbl_no, FALSE);
nuclear@2: 	emit_dht(cinfo, compptr->ac_tbl_no, TRUE);
nuclear@2:       }
nuclear@2:     }
nuclear@2:   }
nuclear@2: 
nuclear@2:   /* Emit DRI if required --- note that DRI value could change for each scan.
nuclear@2:    * We avoid wasting space with unnecessary DRIs, however.
nuclear@2:    */
nuclear@2:   if (cinfo->restart_interval != marker->last_restart_interval) {
nuclear@2:     emit_dri(cinfo);
nuclear@2:     marker->last_restart_interval = cinfo->restart_interval;
nuclear@2:   }
nuclear@2: 
nuclear@2:   emit_sos(cinfo);
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: /*
nuclear@2:  * Write datastream trailer.
nuclear@2:  */
nuclear@2: 
nuclear@2: METHODDEF(void)
nuclear@2: write_file_trailer (j_compress_ptr cinfo)
nuclear@2: {
nuclear@2:   emit_marker(cinfo, M_EOI);
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: /*
nuclear@2:  * Write an abbreviated table-specification datastream.
nuclear@2:  * This consists of SOI, DQT and DHT tables, and EOI.
nuclear@2:  * Any table that is defined and not marked sent_table = TRUE will be
nuclear@2:  * emitted.  Note that all tables will be marked sent_table = TRUE at exit.
nuclear@2:  */
nuclear@2: 
nuclear@2: METHODDEF(void)
nuclear@2: write_tables_only (j_compress_ptr cinfo)
nuclear@2: {
nuclear@2:   int i;
nuclear@2: 
nuclear@2:   emit_marker(cinfo, M_SOI);
nuclear@2: 
nuclear@2:   for (i = 0; i < NUM_QUANT_TBLS; i++) {
nuclear@2:     if (cinfo->quant_tbl_ptrs[i] != NULL)
nuclear@2:       (void) emit_dqt(cinfo, i);
nuclear@2:   }
nuclear@2: 
nuclear@2:   if (! cinfo->arith_code) {
nuclear@2:     for (i = 0; i < NUM_HUFF_TBLS; i++) {
nuclear@2:       if (cinfo->dc_huff_tbl_ptrs[i] != NULL)
nuclear@2: 	emit_dht(cinfo, i, FALSE);
nuclear@2:       if (cinfo->ac_huff_tbl_ptrs[i] != NULL)
nuclear@2: 	emit_dht(cinfo, i, TRUE);
nuclear@2:     }
nuclear@2:   }
nuclear@2: 
nuclear@2:   emit_marker(cinfo, M_EOI);
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: /*
nuclear@2:  * Initialize the marker writer module.
nuclear@2:  */
nuclear@2: 
nuclear@2: GLOBAL(void)
nuclear@2: jinit_marker_writer (j_compress_ptr cinfo)
nuclear@2: {
nuclear@2:   my_marker_ptr marker;
nuclear@2: 
nuclear@2:   /* Create the subobject */
nuclear@2:   marker = (my_marker_ptr)
nuclear@2:     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
nuclear@2: 				SIZEOF(my_marker_writer));
nuclear@2:   cinfo->marker = (struct jpeg_marker_writer *) marker;
nuclear@2:   /* Initialize method pointers */
nuclear@2:   marker->pub.write_file_header = write_file_header;
nuclear@2:   marker->pub.write_frame_header = write_frame_header;
nuclear@2:   marker->pub.write_scan_header = write_scan_header;
nuclear@2:   marker->pub.write_file_trailer = write_file_trailer;
nuclear@2:   marker->pub.write_tables_only = write_tables_only;
nuclear@2:   marker->pub.write_marker_header = write_marker_header;
nuclear@2:   marker->pub.write_marker_byte = write_marker_byte;
nuclear@2:   /* Initialize private state */
nuclear@2:   marker->last_restart_interval = 0;
nuclear@2: }