Bug Summary

File:root/firefox-clang/media/libjpeg/src/jctrans.c
Warning:line 335, column 26
Array access results in an undefined pointer dereference

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -O2 -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name jctrans.c -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -fhalf-no-semantic-interposition -mframe-pointer=all -relaxed-aliasing -ffp-contract=off -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/root/firefox-clang/obj-x86_64-pc-linux-gnu/media/libjpeg -fcoverage-compilation-dir=/root/firefox-clang/obj-x86_64-pc-linux-gnu/media/libjpeg -resource-dir /usr/lib/llvm-23/lib/clang/23 -include /root/firefox-clang/config/gcc_hidden.h -include /root/firefox-clang/obj-x86_64-pc-linux-gnu/mozilla-config.h -I /root/firefox-clang/obj-x86_64-pc-linux-gnu/dist/system_wrappers -U _FORTIFY_SOURCE -D _FORTIFY_SOURCE=2 -D DEBUG=1 -D MOZ_WITH_SIMD=1 -D MOZ_HAS_MOZGLUE -D MOZILLA_INTERNAL_API -D IMPL_LIBXUL -D MOZ_SUPPORT_LEAKCHECKING -D STATIC_EXPORTABLE_JS_API -I /root/firefox-clang/media/libjpeg -I /root/firefox-clang/obj-x86_64-pc-linux-gnu/media/libjpeg -I /root/firefox-clang/media/libjpeg -I /root/firefox-clang/media/libjpeg/src -I /root/firefox-clang/obj-x86_64-pc-linux-gnu/dist/include -I /root/firefox-clang/obj-x86_64-pc-linux-gnu/dist/include/nspr -I /root/firefox-clang/obj-x86_64-pc-linux-gnu/dist/include/nss -D MOZILLA_CLIENT -internal-isystem /usr/lib/llvm-23/lib/clang/23/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/16/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -Wno-error=tautological-type-limit-compare -Wno-range-loop-analysis -Wno-error=deprecated-declarations -Wno-error=array-bounds -Wno-error=free-nonheap-object -Wno-error=atomic-alignment -Wno-error=deprecated-builtins -Wno-psabi -Wno-error=builtin-macro-redefined -Wno-unknown-warning-option -Wno-character-conversion -ferror-limit 19 -fstrict-flex-arrays=1 -stack-protector 2 -fstack-clash-protection -ftrivial-auto-var-init=pattern -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fdiagnostics-absolute-paths -vectorize-loops -vectorize-slp -analyzer-checker optin.performance.Padding -analyzer-output=html -analyzer-config stable-report-filename=true -mllvm -dwarf-linkage-names=Abstract -faddrsig -fdwarf2-cfi-asm -o /tmp/scan-build-2026-09-01-224014-2642839-1 -x c /root/firefox-clang/media/libjpeg/src/jctrans.c
1/*
2 * jctrans.c
3 *
4 * This file was part of the Independent JPEG Group's software:
5 * Copyright (C) 1995-1998, Thomas G. Lane.
6 * Modified 2000-2009 by Guido Vollbeding.
7 * libjpeg-turbo Modifications:
8 * Copyright (C) 2020, 2022, D. R. Commander.
9 * For conditions of distribution and use, see the accompanying README.ijg
10 * file.
11 *
12 * This file contains library routines for transcoding compression,
13 * that is, writing raw DCT coefficient arrays to an output JPEG file.
14 * The routines in jcapimin.c will also be needed by a transcoder.
15 */
16
17#define JPEG_INTERNALS
18#include "jinclude.h"
19#include "jpeglib.h"
20#include "jpegapicomp.h"
21
22
23/* Forward declarations */
24LOCAL(void)static void transencode_master_selection(j_compress_ptr cinfo,
25 jvirt_barray_ptr *coef_arrays);
26LOCAL(void)static void transencode_coef_controller(j_compress_ptr cinfo,
27 jvirt_barray_ptr *coef_arrays);
28
29
30/*
31 * Compression initialization for writing raw-coefficient data.
32 * Before calling this, all parameters and a data destination must be set up.
33 * Call jpeg_finish_compress() to actually write the data.
34 *
35 * The number of passed virtual arrays must match cinfo->num_components.
36 * Note that the virtual arrays need not be filled or even realized at
37 * the time write_coefficients is called; indeed, if the virtual arrays
38 * were requested from this compression object's memory manager, they
39 * typically will be realized during this routine and filled afterwards.
40 */
41
42GLOBAL(void)void
43jpeg_write_coefficients(j_compress_ptr cinfo, jvirt_barray_ptr *coef_arrays)
44{
45 if (cinfo->master->lossless)
46 ERREXIT(cinfo, JERR_NOTIMPL)((cinfo)->err->msg_code = (JERR_NOTIMPL), (*(cinfo)->
err->error_exit) ((j_common_ptr)(cinfo)));
47
48 if (cinfo->global_state != CSTATE_START100)
49 ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state)((cinfo)->err->msg_code = (JERR_BAD_STATE), (cinfo)->
err->msg_parm.i[0] = (cinfo->global_state), (*(cinfo)->
err->error_exit) ((j_common_ptr)(cinfo)));
50 /* Mark all tables to be written */
51 jpeg_suppress_tables(cinfo, FALSE0);
52 /* (Re)initialize error mgr and destination modules */
53 (*cinfo->err->reset_error_mgr) ((j_common_ptr)cinfo);
54 (*cinfo->dest->init_destination) (cinfo);
55 /* Perform master selection of active modules */
56 transencode_master_selection(cinfo, coef_arrays);
57 /* Wait for jpeg_finish_compress() call */
58 cinfo->next_scanline = 0; /* so jpeg_write_marker works */
59 cinfo->global_state = CSTATE_WRCOEFS103;
60}
61
62
63/*
64 * Initialize the compression object with default parameters,
65 * then copy from the source object all parameters needed for lossless
66 * transcoding. Parameters that can be varied without loss (such as
67 * scan script and Huffman optimization) are left in their default states.
68 */
69
70GLOBAL(void)void
71jpeg_copy_critical_parameters(j_decompress_ptr srcinfo, j_compress_ptr dstinfo)
72{
73 JQUANT_TBL **qtblptr;
74 jpeg_component_info *incomp, *outcomp;
75 JQUANT_TBL *c_quant, *slot_quant;
76 int tblno, ci, coefi;
77
78 if (srcinfo->master->lossless)
79 ERREXIT(dstinfo, JERR_NOTIMPL)((dstinfo)->err->msg_code = (JERR_NOTIMPL), (*(dstinfo)
->err->error_exit) ((j_common_ptr)(dstinfo)));
80
81 /* Safety check to ensure start_compress not called yet. */
82 if (dstinfo->global_state != CSTATE_START100)
83 ERREXIT1(dstinfo, JERR_BAD_STATE, dstinfo->global_state)((dstinfo)->err->msg_code = (JERR_BAD_STATE), (dstinfo)
->err->msg_parm.i[0] = (dstinfo->global_state), (*(dstinfo
)->err->error_exit) ((j_common_ptr)(dstinfo)));
84 /* Copy fundamental image dimensions */
85 dstinfo->image_width = srcinfo->image_width;
86 dstinfo->image_height = srcinfo->image_height;
87 dstinfo->input_components = srcinfo->num_components;
88 dstinfo->in_color_space = srcinfo->jpeg_color_space;
89#if JPEG_LIB_VERSION62 >= 70
90 dstinfo->jpeg_width = srcinfo->output_width;
91 dstinfo->jpeg_height = srcinfo->output_height;
92 dstinfo->min_DCT_h_scaled_size = srcinfo->min_DCT_h_scaled_size;
93 dstinfo->min_DCT_v_scaled_size = srcinfo->min_DCT_v_scaled_size;
94#endif
95 /* Initialize all parameters to default values */
96 jpeg_set_defaults(dstinfo);
97 /* jpeg_set_defaults may choose wrong colorspace, eg YCbCr if input is RGB.
98 * Fix it to get the right header markers for the image colorspace.
99 */
100 jpeg_set_colorspace(dstinfo, srcinfo->jpeg_color_space);
101 dstinfo->data_precision = srcinfo->data_precision;
102 dstinfo->CCIR601_sampling = srcinfo->CCIR601_sampling;
103 /* Copy the source's quantization tables. */
104 for (tblno = 0; tblno < NUM_QUANT_TBLS4; tblno++) {
105 if (srcinfo->quant_tbl_ptrs[tblno] != NULL((void*)0)) {
106 qtblptr = &dstinfo->quant_tbl_ptrs[tblno];
107 if (*qtblptr == NULL((void*)0))
108 *qtblptr = jpeg_alloc_quant_table((j_common_ptr)dstinfo);
109 memcpy((*qtblptr)->quantval, srcinfo->quant_tbl_ptrs[tblno]->quantval,
110 sizeof((*qtblptr)->quantval));
111 (*qtblptr)->sent_table = FALSE0;
112 }
113 }
114 /* Copy the source's per-component info.
115 * Note we assume jpeg_set_defaults has allocated the dest comp_info array.
116 */
117 dstinfo->num_components = srcinfo->num_components;
118 if (dstinfo->num_components < 1 || dstinfo->num_components > MAX_COMPONENTS10)
119 ERREXIT2(dstinfo, JERR_COMPONENT_COUNT, dstinfo->num_components,((dstinfo)->err->msg_code = (JERR_COMPONENT_COUNT), (dstinfo
)->err->msg_parm.i[0] = (dstinfo->num_components), (
dstinfo)->err->msg_parm.i[1] = (10), (*(dstinfo)->err
->error_exit) ((j_common_ptr)(dstinfo)))
120 MAX_COMPONENTS)((dstinfo)->err->msg_code = (JERR_COMPONENT_COUNT), (dstinfo
)->err->msg_parm.i[0] = (dstinfo->num_components), (
dstinfo)->err->msg_parm.i[1] = (10), (*(dstinfo)->err
->error_exit) ((j_common_ptr)(dstinfo)));
121 for (ci = 0, incomp = srcinfo->comp_info, outcomp = dstinfo->comp_info;
122 ci < dstinfo->num_components; ci++, incomp++, outcomp++) {
123 outcomp->component_id = incomp->component_id;
124 outcomp->h_samp_factor = incomp->h_samp_factor;
125 outcomp->v_samp_factor = incomp->v_samp_factor;
126 outcomp->quant_tbl_no = incomp->quant_tbl_no;
127 /* Make sure saved quantization table for component matches the qtable
128 * slot. If not, the input file re-used this qtable slot.
129 * IJG encoder currently cannot duplicate this.
130 */
131 tblno = outcomp->quant_tbl_no;
132 if (tblno < 0 || tblno >= NUM_QUANT_TBLS4 ||
133 srcinfo->quant_tbl_ptrs[tblno] == NULL((void*)0))
134 ERREXIT1(dstinfo, JERR_NO_QUANT_TABLE, tblno)((dstinfo)->err->msg_code = (JERR_NO_QUANT_TABLE), (dstinfo
)->err->msg_parm.i[0] = (tblno), (*(dstinfo)->err->
error_exit) ((j_common_ptr)(dstinfo)));
135 slot_quant = srcinfo->quant_tbl_ptrs[tblno];
136 c_quant = incomp->quant_table;
137 if (c_quant != NULL((void*)0)) {
138 for (coefi = 0; coefi < DCTSIZE264; coefi++) {
139 if (c_quant->quantval[coefi] != slot_quant->quantval[coefi])
140 ERREXIT1(dstinfo, JERR_MISMATCHED_QUANT_TABLE, tblno)((dstinfo)->err->msg_code = (JERR_MISMATCHED_QUANT_TABLE
), (dstinfo)->err->msg_parm.i[0] = (tblno), (*(dstinfo)
->err->error_exit) ((j_common_ptr)(dstinfo)));
141 }
142 }
143 /* Note: we do not copy the source's Huffman table assignments;
144 * instead we rely on jpeg_set_colorspace to have made a suitable choice.
145 */
146 }
147 /* Also copy JFIF version and resolution information, if available.
148 * Strictly speaking this isn't "critical" info, but it's nearly
149 * always appropriate to copy it if available. In particular,
150 * if the application chooses to copy JFIF 1.02 extension markers from
151 * the source file, we need to copy the version to make sure we don't
152 * emit a file that has 1.02 extensions but a claimed version of 1.01.
153 * We will *not*, however, copy version info from mislabeled "2.01" files.
154 */
155 if (srcinfo->saw_JFIF_marker) {
156 if (srcinfo->JFIF_major_version == 1) {
157 dstinfo->JFIF_major_version = srcinfo->JFIF_major_version;
158 dstinfo->JFIF_minor_version = srcinfo->JFIF_minor_version;
159 }
160 dstinfo->density_unit = srcinfo->density_unit;
161 dstinfo->X_density = srcinfo->X_density;
162 dstinfo->Y_density = srcinfo->Y_density;
163 }
164}
165
166
167/*
168 * Master selection of compression modules for transcoding.
169 * This substitutes for jcinit.c's initialization of the full compressor.
170 */
171
172LOCAL(void)static void
173transencode_master_selection(j_compress_ptr cinfo,
174 jvirt_barray_ptr *coef_arrays)
175{
176 /* Although we don't actually use input_components for transcoding,
177 * jcmaster.c's initial_setup will complain if input_components is 0.
178 */
179 cinfo->input_components = 1;
180 /* Initialize master control (includes parameter checking/processing) */
181 jinit_c_master_control(cinfo, TRUE1 /* transcode only */);
182
183 /* Entropy encoding: either Huffman or arithmetic coding. */
184 if (cinfo->arith_code) {
185#ifdef C_ARITH_CODING_SUPPORTED
186 jinit_arith_encoder(cinfo);
187#else
188 ERREXIT(cinfo, JERR_ARITH_NOTIMPL)((cinfo)->err->msg_code = (JERR_ARITH_NOTIMPL), (*(cinfo
)->err->error_exit) ((j_common_ptr)(cinfo)));
189#endif
190 } else {
191 if (cinfo->progressive_mode) {
192#ifdef C_PROGRESSIVE_SUPPORTED
193 jinit_phuff_encoder(cinfo);
194#else
195 ERREXIT(cinfo, JERR_NOT_COMPILED)((cinfo)->err->msg_code = (JERR_NOT_COMPILED), (*(cinfo
)->err->error_exit) ((j_common_ptr)(cinfo)));
196#endif
197 } else
198 jinit_huff_encoder(cinfo);
199 }
200
201 /* We need a special coefficient buffer controller. */
202 transencode_coef_controller(cinfo, coef_arrays);
203
204 jinit_marker_writer(cinfo);
205
206 /* We can now tell the memory manager to allocate virtual arrays. */
207 (*cinfo->mem->realize_virt_arrays) ((j_common_ptr)cinfo);
208
209 /* Write the datastream header (SOI, JFIF) immediately.
210 * Frame and scan headers are postponed till later.
211 * This lets application insert special markers after the SOI.
212 */
213 (*cinfo->marker->write_file_header) (cinfo);
214}
215
216
217/*
218 * The rest of this file is a special implementation of the coefficient
219 * buffer controller. This is similar to jccoefct.c, but it handles only
220 * output from presupplied virtual arrays. Furthermore, we generate any
221 * dummy padding blocks on-the-fly rather than expecting them to be present
222 * in the arrays.
223 */
224
225/* Private buffer controller object */
226
227typedef struct {
228 struct jpeg_c_coef_controller pub; /* public fields */
229
230 JDIMENSION iMCU_row_num; /* iMCU row # within image */
231 JDIMENSION mcu_ctr; /* counts MCUs processed in current row */
232 int MCU_vert_offset; /* counts MCU rows within iMCU row */
233 int MCU_rows_per_iMCU_row; /* number of such rows needed */
234
235 /* Virtual block array for each component. */
236 jvirt_barray_ptr *whole_image;
237
238 /* Workspace for constructing dummy blocks at right/bottom edges. */
239 JBLOCKROW dummy_buffer[C_MAX_BLOCKS_IN_MCU10];
240} my_coef_controller;
241
242typedef my_coef_controller *my_coef_ptr;
243
244
245LOCAL(void)static void
246start_iMCU_row(j_compress_ptr cinfo)
247/* Reset within-iMCU-row counters for a new row */
248{
249 my_coef_ptr coef = (my_coef_ptr)cinfo->coef;
250
251 /* In an interleaved scan, an MCU row is the same as an iMCU row.
252 * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows.
253 * But at the bottom of the image, process only what's left.
254 */
255 if (cinfo->comps_in_scan > 1) {
256 coef->MCU_rows_per_iMCU_row = 1;
257 } else {
258 if (coef->iMCU_row_num < (cinfo->total_iMCU_rows - 1))
259 coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor;
260 else
261 coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height;
262 }
263
264 coef->mcu_ctr = 0;
265 coef->MCU_vert_offset = 0;
266}
267
268
269/*
270 * Initialize for a processing pass.
271 */
272
273METHODDEF(void)static void
274start_pass_coef(j_compress_ptr cinfo, J_BUF_MODE pass_mode)
275{
276 my_coef_ptr coef = (my_coef_ptr)cinfo->coef;
277
278 if (pass_mode != JBUF_CRANK_DEST)
279 ERREXIT(cinfo, JERR_BAD_BUFFER_MODE)((cinfo)->err->msg_code = (JERR_BAD_BUFFER_MODE), (*(cinfo
)->err->error_exit) ((j_common_ptr)(cinfo)));
280
281 coef->iMCU_row_num = 0;
282 start_iMCU_row(cinfo);
283}
284
285
286/*
287 * Process some data.
288 * We process the equivalent of one fully interleaved MCU row ("iMCU" row)
289 * per call, ie, v_samp_factor block rows for each component in the scan.
290 * The data is obtained from the virtual arrays and fed to the entropy coder.
291 * Returns TRUE if the iMCU row is completed, FALSE if suspended.
292 *
293 * NB: input_buf is ignored; it is likely to be a NULL pointer.
294 */
295
296METHODDEF(boolean)static boolean
297compress_output(j_compress_ptr cinfo, JSAMPIMAGE input_buf)
298{
299 my_coef_ptr coef = (my_coef_ptr)cinfo->coef;
300 JDIMENSION MCU_col_num; /* index of current MCU within row */
301 JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1;
302 JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;
303 int blkn, ci, xindex, yindex, yoffset, blockcnt;
304 JDIMENSION start_col;
305 JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN4];
306 JBLOCKROW MCU_buffer[C_MAX_BLOCKS_IN_MCU10];
307 JBLOCKROW buffer_ptr;
308 jpeg_component_info *compptr;
309
310 /* Align the virtual buffers for the components used in this scan. */
311 for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
2
←
Assuming 'ci' is >= field 'comps_in_scan'
→
3
←
Loop condition is false. Execution continues on line 320
→
312 compptr = cinfo->cur_comp_info[ci];
313 buffer[ci] = (*cinfo->mem->access_virt_barray)
314 ((j_common_ptr)cinfo, coef->whole_image[compptr->component_index],
315 coef->iMCU_row_num * compptr->v_samp_factor,
316 (JDIMENSION)compptr->v_samp_factor, FALSE0);
317 }
318
319 /* Loop to process one whole iMCU row */
320 for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row;
4
←
Assuming 'yoffset' is < field 'MCU_rows_per_iMCU_row'
→
5
←
Loop condition is true. Entering loop body
→
321 yoffset++) {
322 for (MCU_col_num = coef->mcu_ctr; MCU_col_num < cinfo->MCUs_per_row;
6
←
Assuming 'MCU_col_num' is < field 'MCUs_per_row'
→
7
←
Loop condition is true. Entering loop body
→
11
←
Assuming 'MCU_col_num' is < field 'MCUs_per_row'
→
12
←
Loop condition is true. Entering loop body
→
323 MCU_col_num++) {
324 /* Construct list of pointers to DCT blocks belonging to this MCU */
325 blkn = 0; /* index of current DCT block within MCU */
326 for (ci = 0; ci
7.1
'ci' is >= field 'comps_in_scan'
 < cinfo->comps_in_scan; ci++) {
8
←
Loop condition is false. Execution continues on line 356
→
13
←
The value 0 is assigned to 'ci'
→
14
←
Assuming 'ci' is < field 'comps_in_scan'
→
15
←
Loop condition is true. Entering loop body
→
327 compptr = cinfo->cur_comp_info[ci];
328 start_col = MCU_col_num * compptr->MCU_width;
329 blockcnt = (MCU_col_num < last_MCU_col) ? compptr->MCU_width :
16
←
Assuming 'MCU_col_num' is >= 'last_MCU_col'
→
17
←
'?' condition is false
→
330 compptr->last_col_width;
331 for (yindex = 0; yindex < compptr->MCU_height; yindex++) {
18
←
Assuming 'yindex' is < field 'MCU_height'
→
332 if (coef->iMCU_row_num < last_iMCU_row ||
19
←
Assuming 'last_iMCU_row' is > field 'iMCU_row_num'
→
333 yindex + yoffset < compptr->last_row_height) {
334 /* Fill in pointers to real blocks in this row */
335 buffer_ptr = buffer[ci][yindex + yoffset] + start_col;
20
←
Array access results in an undefined pointer dereference
336 for (xindex = 0; xindex < blockcnt; xindex++)
337 MCU_buffer[blkn++] = buffer_ptr++;
338 } else {
339 /* At bottom of image, need a whole row of dummy blocks */
340 xindex = 0;
341 }
342 /* Fill in any dummy blocks needed in this row.
343 * Dummy blocks are filled in the same way as in jccoefct.c:
344 * all zeroes in the AC entries, DC entries equal to previous
345 * block's DC value. The init routine has already zeroed the
346 * AC entries, so we need only set the DC entries correctly.
347 */
348 for (; xindex < compptr->MCU_width; xindex++) {
349 MCU_buffer[blkn] = coef->dummy_buffer[blkn];
350 MCU_buffer[blkn][0][0] = MCU_buffer[blkn - 1][0][0];
351 blkn++;
352 }
353 }
354 }
355 /* Try to write the MCU. */
356 if (!(*cinfo->entropy->encode_mcu) (cinfo, MCU_buffer)) {
9
←
Assuming the condition is false
→
10
←
Taking false branch
→
357 /* Suspension forced; update state counters and exit */
358 coef->MCU_vert_offset = yoffset;
359 coef->mcu_ctr = MCU_col_num;
360 return FALSE0;
361 }
362 }
363 /* Completed an MCU row, but perhaps not an iMCU row */
364 coef->mcu_ctr = 0;
365 }
366 /* Completed the iMCU row, advance counters for next one */
367 coef->iMCU_row_num++;
368 start_iMCU_row(cinfo);
369 return TRUE1;
370}
371
372
373METHODDEF(boolean)static boolean
374compress_output_12(j_compress_ptr cinfo, J12SAMPIMAGE input_buf)
375{
376 return compress_output(cinfo, (JSAMPIMAGE)input_buf);
1
Calling 'compress_output'
→
377}
378
379
380/*
381 * Initialize coefficient buffer controller.
382 *
383 * Each passed coefficient array must be the right size for that
384 * coefficient: width_in_blocks wide and height_in_blocks high,
385 * with unitheight at least v_samp_factor.
386 */
387
388LOCAL(void)static void
389transencode_coef_controller(j_compress_ptr cinfo,
390 jvirt_barray_ptr *coef_arrays)
391{
392 my_coef_ptr coef;
393 JBLOCKROW buffer;
394 int i;
395
396 coef = (my_coef_ptr)
397 (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE1,
398 sizeof(my_coef_controller));
399 cinfo->coef = (struct jpeg_c_coef_controller *)coef;
400 coef->pub.start_pass = start_pass_coef;
401 coef->pub.compress_data = compress_output;
402 coef->pub.compress_data_12 = compress_output_12;
403
404 /* Save pointer to virtual arrays */
405 coef->whole_image = coef_arrays;
406
407 /* Allocate and pre-zero space for dummy DCT blocks. */
408 buffer = (JBLOCKROW)
409 (*cinfo->mem->alloc_large) ((j_common_ptr)cinfo, JPOOL_IMAGE1,
410 C_MAX_BLOCKS_IN_MCU10 * sizeof(JBLOCK));
411 jzero_far((void *)buffer, C_MAX_BLOCKS_IN_MCU10 * sizeof(JBLOCK));
412 for (i = 0; i < C_MAX_BLOCKS_IN_MCU10; i++) {
413 coef->dummy_buffer[i] = buffer + i;
414 }
415}