1 #if !defined(_FX_JPEG_TURBO_)
2 /*
3 * jctrans.c
4 *
5 * Copyright (C) 1995-1998, 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 library routines for transcoding compression,
10 * that is, writing raw DCT coefficient arrays to an output JPEG file.
11 * The routines in jcapimin.c will also be needed by a transcoder.
12 */
13
14 #define JPEG_INTERNALS
15 #include "jinclude.h"
16 #include "jpeglib.h"
17
18
19 /* Forward declarations */
20 LOCAL(void) transencode_master_selection
21 JPP((j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays));
22 LOCAL(void) transencode_coef_controller
23 JPP((j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays));
24
25
26 /*
27 * Compression initialization for writing raw-coefficient data.
28 * Before calling this, all parameters and a data destination must be set up.
29 * Call jpeg_finish_compress() to actually write the data.
30 *
31 * The number of passed virtual arrays must match cinfo->num_components.
32 * Note that the virtual arrays need not be filled or even realized at
33 * the time write_coefficients is called; indeed, if the virtual arrays
34 * were requested from this compression object's memory manager, they
35 * typically will be realized during this routine and filled afterwards.
36 */
37
38 GLOBAL(void)
jpeg_write_coefficients(j_compress_ptr cinfo,jvirt_barray_ptr * coef_arrays)39 jpeg_write_coefficients (j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays)
40 {
41 if (cinfo->global_state != CSTATE_START)
42 ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
43 /* Mark all tables to be written */
44 jpeg_suppress_tables(cinfo, FALSE);
45 /* (Re)initialize error mgr and destination modules */
46 (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
47 (*cinfo->dest->init_destination) (cinfo);
48 /* Perform master selection of active modules */
49 transencode_master_selection(cinfo, coef_arrays);
50 /* Wait for jpeg_finish_compress() call */
51 cinfo->next_scanline = 0; /* so jpeg_write_marker works */
52 cinfo->global_state = CSTATE_WRCOEFS;
53 }
54
55
56 /*
57 * Initialize the compression object with default parameters,
58 * then copy from the source object all parameters needed for lossless
59 * transcoding. Parameters that can be varied without loss (such as
60 * scan script and Huffman optimization) are left in their default states.
61 */
62
63 GLOBAL(void)
jpeg_copy_critical_parameters(j_decompress_ptr srcinfo,j_compress_ptr dstinfo)64 jpeg_copy_critical_parameters (j_decompress_ptr srcinfo,
65 j_compress_ptr dstinfo)
66 {
67 JQUANT_TBL ** qtblptr;
68 jpeg_component_info *incomp, *outcomp;
69 JQUANT_TBL *c_quant, *slot_quant;
70 int tblno, ci, coefi;
71
72 /* Safety check to ensure start_compress not called yet. */
73 if (dstinfo->global_state != CSTATE_START)
74 ERREXIT1(dstinfo, JERR_BAD_STATE, dstinfo->global_state);
75 /* Copy fundamental image dimensions */
76 dstinfo->image_width = srcinfo->image_width;
77 dstinfo->image_height = srcinfo->image_height;
78 dstinfo->input_components = srcinfo->num_components;
79 dstinfo->in_color_space = srcinfo->jpeg_color_space;
80 /* Initialize all parameters to default values */
81 jpeg_set_defaults(dstinfo);
82 /* jpeg_set_defaults may choose wrong colorspace, eg YCbCr if input is RGB.
83 * Fix it to get the right header markers for the image colorspace.
84 */
85 jpeg_set_colorspace(dstinfo, srcinfo->jpeg_color_space);
86 dstinfo->data_precision = srcinfo->data_precision;
87 dstinfo->CCIR601_sampling = srcinfo->CCIR601_sampling;
88 /* Copy the source's quantization tables. */
89 for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {
90 if (srcinfo->quant_tbl_ptrs[tblno] != NULL) {
91 qtblptr = & dstinfo->quant_tbl_ptrs[tblno];
92 if (*qtblptr == NULL)
93 *qtblptr = jpeg_alloc_quant_table((j_common_ptr) dstinfo);
94 MEMCOPY((*qtblptr)->quantval,
95 srcinfo->quant_tbl_ptrs[tblno]->quantval,
96 SIZEOF((*qtblptr)->quantval));
97 (*qtblptr)->sent_table = FALSE;
98 }
99 }
100 /* Copy the source's per-component info.
101 * Note we assume jpeg_set_defaults has allocated the dest comp_info array.
102 */
103 dstinfo->num_components = srcinfo->num_components;
104 if (dstinfo->num_components < 1 || dstinfo->num_components > MAX_COMPONENTS)
105 ERREXIT2(dstinfo, JERR_COMPONENT_COUNT, dstinfo->num_components,
106 MAX_COMPONENTS);
107 for (ci = 0, incomp = srcinfo->comp_info, outcomp = dstinfo->comp_info;
108 ci < dstinfo->num_components; ci++, incomp++, outcomp++) {
109 outcomp->component_id = incomp->component_id;
110 outcomp->h_samp_factor = incomp->h_samp_factor;
111 outcomp->v_samp_factor = incomp->v_samp_factor;
112 outcomp->quant_tbl_no = incomp->quant_tbl_no;
113 /* Make sure saved quantization table for component matches the qtable
114 * slot. If not, the input file re-used this qtable slot.
115 * IJG encoder currently cannot duplicate this.
116 */
117 tblno = outcomp->quant_tbl_no;
118 if (tblno < 0 || tblno >= NUM_QUANT_TBLS ||
119 srcinfo->quant_tbl_ptrs[tblno] == NULL)
120 ERREXIT1(dstinfo, JERR_NO_QUANT_TABLE, tblno);
121 slot_quant = srcinfo->quant_tbl_ptrs[tblno];
122 c_quant = incomp->quant_table;
123 if (c_quant != NULL) {
124 for (coefi = 0; coefi < DCTSIZE2; coefi++) {
125 if (c_quant->quantval[coefi] != slot_quant->quantval[coefi])
126 ERREXIT1(dstinfo, JERR_MISMATCHED_QUANT_TABLE, tblno);
127 }
128 }
129 /* Note: we do not copy the source's Huffman table assignments;
130 * instead we rely on jpeg_set_colorspace to have made a suitable choice.
131 */
132 }
133 /* Also copy JFIF version and resolution information, if available.
134 * Strictly speaking this isn't "critical" info, but it's nearly
135 * always appropriate to copy it if available. In particular,
136 * if the application chooses to copy JFIF 1.02 extension markers from
137 * the source file, we need to copy the version to make sure we don't
138 * emit a file that has 1.02 extensions but a claimed version of 1.01.
139 * We will *not*, however, copy version info from mislabeled "2.01" files.
140 */
141 if (srcinfo->saw_JFIF_marker) {
142 if (srcinfo->JFIF_major_version == 1) {
143 dstinfo->JFIF_major_version = srcinfo->JFIF_major_version;
144 dstinfo->JFIF_minor_version = srcinfo->JFIF_minor_version;
145 }
146 dstinfo->density_unit = srcinfo->density_unit;
147 dstinfo->X_density = srcinfo->X_density;
148 dstinfo->Y_density = srcinfo->Y_density;
149 }
150 }
151
152
153 /*
154 * Master selection of compression modules for transcoding.
155 * This substitutes for jcinit.c's initialization of the full compressor.
156 */
157
158 LOCAL(void)
transencode_master_selection(j_compress_ptr cinfo,jvirt_barray_ptr * coef_arrays)159 transencode_master_selection (j_compress_ptr cinfo,
160 jvirt_barray_ptr * coef_arrays)
161 {
162 /* Although we don't actually use input_components for transcoding,
163 * jcmaster.c's initial_setup will complain if input_components is 0.
164 */
165 cinfo->input_components = 1;
166 /* Initialize master control (includes parameter checking/processing) */
167 jinit_c_master_control(cinfo, TRUE /* transcode only */);
168
169 /* Entropy encoding: either Huffman or arithmetic coding. */
170 if (cinfo->arith_code) {
171 ERREXIT(cinfo, JERR_ARITH_NOTIMPL);
172 } else {
173 if (cinfo->progressive_mode) {
174 #ifdef C_PROGRESSIVE_SUPPORTED
175 jinit_phuff_encoder(cinfo);
176 #else
177 ERREXIT(cinfo, JERR_NOT_COMPILED);
178 #endif
179 } else
180 jinit_huff_encoder(cinfo);
181 }
182
183 /* We need a special coefficient buffer controller. */
184 transencode_coef_controller(cinfo, coef_arrays);
185
186 jinit_marker_writer(cinfo);
187
188 /* We can now tell the memory manager to allocate virtual arrays. */
189 (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);
190
191 /* Write the datastream header (SOI, JFIF) immediately.
192 * Frame and scan headers are postponed till later.
193 * This lets application insert special markers after the SOI.
194 */
195 (*cinfo->marker->write_file_header) (cinfo);
196 }
197
198
199 /*
200 * The rest of this file is a special implementation of the coefficient
201 * buffer controller. This is similar to jccoefct.c, but it handles only
202 * output from presupplied virtual arrays. Furthermore, we generate any
203 * dummy padding blocks on-the-fly rather than expecting them to be present
204 * in the arrays.
205 */
206
207 /* Private buffer controller object */
208
209 typedef struct {
210 struct jpeg_c_coef_controller pub; /* public fields */
211
212 JDIMENSION iMCU_row_num; /* iMCU row # within image */
213 JDIMENSION mcu_ctr; /* counts MCUs processed in current row */
214 int MCU_vert_offset; /* counts MCU rows within iMCU row */
215 int MCU_rows_per_iMCU_row; /* number of such rows needed */
216
217 /* Virtual block array for each component. */
218 jvirt_barray_ptr * whole_image;
219
220 /* Workspace for constructing dummy blocks at right/bottom edges. */
221 JBLOCKROW dummy_buffer[C_MAX_BLOCKS_IN_MCU];
222 } my_coef_controller;
223
224 typedef my_coef_controller * my_coef_ptr;
225
226
227 LOCAL(void)
start_iMCU_row(j_compress_ptr cinfo)228 start_iMCU_row (j_compress_ptr cinfo)
229 /* Reset within-iMCU-row counters for a new row */
230 {
231 my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
232
233 /* In an interleaved scan, an MCU row is the same as an iMCU row.
234 * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows.
235 * But at the bottom of the image, process only what's left.
236 */
237 if (cinfo->comps_in_scan > 1) {
238 coef->MCU_rows_per_iMCU_row = 1;
239 } else {
240 if (coef->iMCU_row_num < (cinfo->total_iMCU_rows-1))
241 coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor;
242 else
243 coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height;
244 }
245
246 coef->mcu_ctr = 0;
247 coef->MCU_vert_offset = 0;
248 }
249
250
251 /*
252 * Initialize for a processing pass.
253 */
254
255 METHODDEF(void)
start_pass_coef(j_compress_ptr cinfo,J_BUF_MODE pass_mode)256 start_pass_coef (j_compress_ptr cinfo, J_BUF_MODE pass_mode)
257 {
258 my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
259
260 if (pass_mode != JBUF_CRANK_DEST)
261 ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
262
263 coef->iMCU_row_num = 0;
264 start_iMCU_row(cinfo);
265 }
266
267
268 /*
269 * Process some data.
270 * We process the equivalent of one fully interleaved MCU row ("iMCU" row)
271 * per call, ie, v_samp_factor block rows for each component in the scan.
272 * The data is obtained from the virtual arrays and fed to the entropy coder.
273 * Returns TRUE if the iMCU row is completed, FALSE if suspended.
274 *
275 * NB: input_buf is ignored; it is likely to be a NULL pointer.
276 */
277
278 METHODDEF(boolean)
compress_output(j_compress_ptr cinfo,JSAMPIMAGE input_buf)279 compress_output (j_compress_ptr cinfo, JSAMPIMAGE input_buf)
280 {
281 my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
282 JDIMENSION MCU_col_num; /* index of current MCU within row */
283 JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1;
284 JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;
285 int blkn, ci, xindex, yindex, yoffset, blockcnt;
286 JDIMENSION start_col;
287 JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN];
288 JBLOCKROW MCU_buffer[C_MAX_BLOCKS_IN_MCU];
289 JBLOCKROW buffer_ptr;
290 jpeg_component_info *compptr;
291
292 /* Align the virtual buffers for the components used in this scan. */
293 for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
294 compptr = cinfo->cur_comp_info[ci];
295 buffer[ci] = (*cinfo->mem->access_virt_barray)
296 ((j_common_ptr) cinfo, coef->whole_image[compptr->component_index],
297 coef->iMCU_row_num * compptr->v_samp_factor,
298 (JDIMENSION) compptr->v_samp_factor, FALSE);
299 }
300
301 /* Loop to process one whole iMCU row */
302 for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row;
303 yoffset++) {
304 for (MCU_col_num = coef->mcu_ctr; MCU_col_num < cinfo->MCUs_per_row;
305 MCU_col_num++) {
306 /* Construct list of pointers to DCT blocks belonging to this MCU */
307 blkn = 0; /* index of current DCT block within MCU */
308 for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
309 compptr = cinfo->cur_comp_info[ci];
310 start_col = MCU_col_num * compptr->MCU_width;
311 blockcnt = (MCU_col_num < last_MCU_col) ? compptr->MCU_width
312 : compptr->last_col_width;
313 for (yindex = 0; yindex < compptr->MCU_height; yindex++) {
314 if (coef->iMCU_row_num < last_iMCU_row ||
315 yindex+yoffset < compptr->last_row_height) {
316 /* Fill in pointers to real blocks in this row */
317 buffer_ptr = buffer[ci][yindex+yoffset] + start_col;
318 for (xindex = 0; xindex < blockcnt; xindex++)
319 MCU_buffer[blkn++] = buffer_ptr++;
320 } else {
321 /* At bottom of image, need a whole row of dummy blocks */
322 xindex = 0;
323 }
324 /* Fill in any dummy blocks needed in this row.
325 * Dummy blocks are filled in the same way as in jccoefct.c:
326 * all zeroes in the AC entries, DC entries equal to previous
327 * block's DC value. The init routine has already zeroed the
328 * AC entries, so we need only set the DC entries correctly.
329 */
330 for (; xindex < compptr->MCU_width; xindex++) {
331 MCU_buffer[blkn] = coef->dummy_buffer[blkn];
332 MCU_buffer[blkn][0][0] = MCU_buffer[blkn-1][0][0];
333 blkn++;
334 }
335 }
336 }
337 /* Try to write the MCU. */
338 if (! (*cinfo->entropy->encode_mcu) (cinfo, MCU_buffer)) {
339 /* Suspension forced; update state counters and exit */
340 coef->MCU_vert_offset = yoffset;
341 coef->mcu_ctr = MCU_col_num;
342 return FALSE;
343 }
344 }
345 /* Completed an MCU row, but perhaps not an iMCU row */
346 coef->mcu_ctr = 0;
347 }
348 /* Completed the iMCU row, advance counters for next one */
349 coef->iMCU_row_num++;
350 start_iMCU_row(cinfo);
351 return TRUE;
352 }
353
354
355 /*
356 * Initialize coefficient buffer controller.
357 *
358 * Each passed coefficient array must be the right size for that
359 * coefficient: width_in_blocks wide and height_in_blocks high,
360 * with unitheight at least v_samp_factor.
361 */
362
363 LOCAL(void)
transencode_coef_controller(j_compress_ptr cinfo,jvirt_barray_ptr * coef_arrays)364 transencode_coef_controller (j_compress_ptr cinfo,
365 jvirt_barray_ptr * coef_arrays)
366 {
367 my_coef_ptr coef;
368 JBLOCKROW buffer;
369 int i;
370
371 coef = (my_coef_ptr)
372 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
373 SIZEOF(my_coef_controller));
374 cinfo->coef = (struct jpeg_c_coef_controller *) coef;
375 coef->pub.start_pass = start_pass_coef;
376 coef->pub.compress_data = compress_output;
377
378 /* Save pointer to virtual arrays */
379 coef->whole_image = coef_arrays;
380
381 /* Allocate and pre-zero space for dummy DCT blocks. */
382 buffer = (JBLOCKROW)
383 (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,
384 C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));
385 jzero_far((void FAR *) buffer, C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));
386 for (i = 0; i < C_MAX_BLOCKS_IN_MCU; i++) {
387 coef->dummy_buffer[i] = buffer + i;
388 }
389 }
390
391 #endif //_FX_JPEG_TURBO_
392