1#if !defined(_FX_JPEG_TURBO_)
2/*
3 * jcapistd.c
4 *
5 * Copyright (C) 1994-1996, Thomas G. Lane.
6 * This file is part of the Independent JPEG Group's software.
7 * For conditions of distribution and use, see the accompanying README file.
8 *
9 * This file contains application interface code for the compression half
10 * of the JPEG library.  These are the "standard" API routines that are
11 * used in the normal full-compression case.  They are not used by a
12 * transcoding-only application.  Note that if an application links in
13 * jpeg_start_compress, it will end up linking in the entire compressor.
14 * We thus must separate this file from jcapimin.c to avoid linking the
15 * whole compression library into a transcoder.
16 */
17
18#define JPEG_INTERNALS
19#include "jinclude.h"
20#include "jpeglib.h"
21
22
23/*
24 * Compression initialization.
25 * Before calling this, all parameters and a data destination must be set up.
26 *
27 * We require a write_all_tables parameter as a failsafe check when writing
28 * multiple datastreams from the same compression object.  Since prior runs
29 * will have left all the tables marked sent_table=TRUE, a subsequent run
30 * would emit an abbreviated stream (no tables) by default.  This may be what
31 * is wanted, but for safety's sake it should not be the default behavior:
32 * programmers should have to make a deliberate choice to emit abbreviated
33 * images.  Therefore the documentation and examples should encourage people
34 * to pass write_all_tables=TRUE; then it will take active thought to do the
35 * wrong thing.
36 */
37
38GLOBAL(void)
39jpeg_start_compress (j_compress_ptr cinfo, boolean write_all_tables)
40{
41  if (cinfo->global_state != CSTATE_START)
42    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
43
44  if (write_all_tables)
45    jpeg_suppress_tables(cinfo, FALSE);	/* mark all tables to be written */
46
47  /* (Re)initialize error mgr and destination modules */
48  (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
49  (*cinfo->dest->init_destination) (cinfo);
50  /* Perform master selection of active modules */
51  jinit_compress_master(cinfo);
52  /* Set up for the first pass */
53  (*cinfo->master->prepare_for_pass) (cinfo);
54  /* Ready for application to drive first pass through jpeg_write_scanlines
55   * or jpeg_write_raw_data.
56   */
57  cinfo->next_scanline = 0;
58  cinfo->global_state = (cinfo->raw_data_in ? CSTATE_RAW_OK : CSTATE_SCANNING);
59}
60
61
62/*
63 * Write some scanlines of data to the JPEG compressor.
64 *
65 * The return value will be the number of lines actually written.
66 * This should be less than the supplied num_lines only in case that
67 * the data destination module has requested suspension of the compressor,
68 * or if more than image_height scanlines are passed in.
69 *
70 * Note: we warn about excess calls to jpeg_write_scanlines() since
71 * this likely signals an application programmer error.  However,
72 * excess scanlines passed in the last valid call are *silently* ignored,
73 * so that the application need not adjust num_lines for end-of-image
74 * when using a multiple-scanline buffer.
75 */
76
77GLOBAL(JDIMENSION)
78jpeg_write_scanlines (j_compress_ptr cinfo, JSAMPARRAY scanlines,
79		      JDIMENSION num_lines)
80{
81  JDIMENSION row_ctr, rows_left;
82
83  if (cinfo->global_state != CSTATE_SCANNING)
84    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
85  if (cinfo->next_scanline >= cinfo->image_height)
86    WARNMS(cinfo, JWRN_TOO_MUCH_DATA);
87
88  /* Call progress monitor hook if present */
89  if (cinfo->progress != NULL) {
90    cinfo->progress->pass_counter = (long) cinfo->next_scanline;
91    cinfo->progress->pass_limit = (long) cinfo->image_height;
92    (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
93  }
94
95  /* Give master control module another chance if this is first call to
96   * jpeg_write_scanlines.  This lets output of the frame/scan headers be
97   * delayed so that application can write COM, etc, markers between
98   * jpeg_start_compress and jpeg_write_scanlines.
99   */
100  if (cinfo->master->call_pass_startup)
101    (*cinfo->master->pass_startup) (cinfo);
102
103  /* Ignore any extra scanlines at bottom of image. */
104  rows_left = cinfo->image_height - cinfo->next_scanline;
105  if (num_lines > rows_left)
106    num_lines = rows_left;
107
108  row_ctr = 0;
109  (*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, num_lines);
110  cinfo->next_scanline += row_ctr;
111  return row_ctr;
112}
113
114
115/*
116 * Alternate entry point to write raw data.
117 * Processes exactly one iMCU row per call, unless suspended.
118 */
119
120GLOBAL(JDIMENSION)
121jpeg_write_raw_data (j_compress_ptr cinfo, JSAMPIMAGE data,
122		     JDIMENSION num_lines)
123{
124  JDIMENSION lines_per_iMCU_row;
125
126  if (cinfo->global_state != CSTATE_RAW_OK)
127    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
128  if (cinfo->next_scanline >= cinfo->image_height) {
129    WARNMS(cinfo, JWRN_TOO_MUCH_DATA);
130    return 0;
131  }
132
133  /* Call progress monitor hook if present */
134  if (cinfo->progress != NULL) {
135    cinfo->progress->pass_counter = (long) cinfo->next_scanline;
136    cinfo->progress->pass_limit = (long) cinfo->image_height;
137    (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
138  }
139
140  /* Give master control module another chance if this is first call to
141   * jpeg_write_raw_data.  This lets output of the frame/scan headers be
142   * delayed so that application can write COM, etc, markers between
143   * jpeg_start_compress and jpeg_write_raw_data.
144   */
145  if (cinfo->master->call_pass_startup)
146    (*cinfo->master->pass_startup) (cinfo);
147
148  /* Verify that at least one iMCU row has been passed. */
149  lines_per_iMCU_row = cinfo->max_v_samp_factor * DCTSIZE;
150  if (num_lines < lines_per_iMCU_row)
151    ERREXIT(cinfo, JERR_BUFFER_SIZE);
152
153  /* Directly compress the row. */
154  if (! (*cinfo->coef->compress_data) (cinfo, data)) {
155    /* If compressor did not consume the whole row, suspend processing. */
156    return 0;
157  }
158
159  /* OK, we processed one iMCU row. */
160  cinfo->next_scanline += lines_per_iMCU_row;
161  return lines_per_iMCU_row;
162}
163
164#endif //_FX_JPEG_TURBO_
165