/* * 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 #include #include "morecfg.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; #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; extern const int jpeg_natural_order[]; 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[jpeg_natural_order[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 #endif void write_jpeg_file(JOCTET *entropy_data, int nsymbols) { my_destination_mgr destination; size_t datacount; int symbol_index; /* 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 */ for (symbol_index = nsymbols ;symbol_index < nsymbols; symbol_index++) { emit_byte(&destination, entropy_data[symbol_index]); } /* 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); }