hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 1 | /* |
| 2 | * jdmainct.c |
| 3 | * |
noel@chromium.org | 3395bcc | 2014-04-14 06:56:00 +0000 | [diff] [blame] | 4 | * This file was part of the Independent JPEG Group's software: |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 5 | * Copyright (C) 1994-1996, Thomas G. Lane. |
noel@chromium.org | 3395bcc | 2014-04-14 06:56:00 +0000 | [diff] [blame] | 6 | * libjpeg-turbo Modifications: |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 7 | * Copyright (C) 2010, 2016, D. R. Commander. |
| 8 | * For conditions of distribution and use, see the accompanying README.ijg |
| 9 | * file. |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 10 | * |
| 11 | * This file contains the main buffer controller for decompression. |
| 12 | * The main buffer lies between the JPEG decompressor proper and the |
| 13 | * post-processor; it holds downsampled data in the JPEG colorspace. |
| 14 | * |
| 15 | * Note that this code is bypassed in raw-data mode, since the application |
| 16 | * supplies the equivalent of the main buffer in that case. |
| 17 | */ |
| 18 | |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 19 | #include "jinclude.h" |
Aaron Gable | c9c8755 | 2015-08-03 09:34:32 -0700 | [diff] [blame] | 20 | #include "jdmainct.h" |
Peter Kasting | 2eb7e20 | 2021-07-09 07:13:34 -0700 | [diff] [blame] | 21 | #include "jconfigint.h" |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 22 | |
| 23 | |
| 24 | /* |
| 25 | * In the current system design, the main buffer need never be a full-image |
| 26 | * buffer; any full-height buffers will be found inside the coefficient or |
| 27 | * postprocessing controllers. Nonetheless, the main controller is not |
| 28 | * trivial. Its responsibility is to provide context rows for upsampling/ |
| 29 | * rescaling, and doing this in an efficient fashion is a bit tricky. |
| 30 | * |
| 31 | * Postprocessor input data is counted in "row groups". A row group |
| 32 | * is defined to be (v_samp_factor * DCT_scaled_size / min_DCT_scaled_size) |
| 33 | * sample rows of each component. (We require DCT_scaled_size values to be |
| 34 | * chosen such that these numbers are integers. In practice DCT_scaled_size |
| 35 | * values will likely be powers of two, so we actually have the stronger |
| 36 | * condition that DCT_scaled_size / min_DCT_scaled_size is an integer.) |
| 37 | * Upsampling will typically produce max_v_samp_factor pixel rows from each |
| 38 | * row group (times any additional scale factor that the upsampler is |
| 39 | * applying). |
| 40 | * |
| 41 | * The coefficient controller will deliver data to us one iMCU row at a time; |
| 42 | * each iMCU row contains v_samp_factor * DCT_scaled_size sample rows, or |
| 43 | * exactly min_DCT_scaled_size row groups. (This amount of data corresponds |
| 44 | * to one row of MCUs when the image is fully interleaved.) Note that the |
| 45 | * number of sample rows varies across components, but the number of row |
| 46 | * groups does not. Some garbage sample rows may be included in the last iMCU |
| 47 | * row at the bottom of the image. |
| 48 | * |
| 49 | * Depending on the vertical scaling algorithm used, the upsampler may need |
| 50 | * access to the sample row(s) above and below its current input row group. |
| 51 | * The upsampler is required to set need_context_rows TRUE at global selection |
| 52 | * time if so. When need_context_rows is FALSE, this controller can simply |
| 53 | * obtain one iMCU row at a time from the coefficient controller and dole it |
| 54 | * out as row groups to the postprocessor. |
| 55 | * |
| 56 | * When need_context_rows is TRUE, this controller guarantees that the buffer |
| 57 | * passed to postprocessing contains at least one row group's worth of samples |
| 58 | * above and below the row group(s) being processed. Note that the context |
| 59 | * rows "above" the first passed row group appear at negative row offsets in |
| 60 | * the passed buffer. At the top and bottom of the image, the required |
| 61 | * context rows are manufactured by duplicating the first or last real sample |
| 62 | * row; this avoids having special cases in the upsampling inner loops. |
| 63 | * |
| 64 | * The amount of context is fixed at one row group just because that's a |
| 65 | * convenient number for this controller to work with. The existing |
| 66 | * upsamplers really only need one sample row of context. An upsampler |
| 67 | * supporting arbitrary output rescaling might wish for more than one row |
| 68 | * group of context when shrinking the image; tough, we don't handle that. |
| 69 | * (This is justified by the assumption that downsizing will be handled mostly |
| 70 | * by adjusting the DCT_scaled_size values, so that the actual scale factor at |
| 71 | * the upsample step needn't be much less than one.) |
| 72 | * |
| 73 | * To provide the desired context, we have to retain the last two row groups |
| 74 | * of one iMCU row while reading in the next iMCU row. (The last row group |
| 75 | * can't be processed until we have another row group for its below-context, |
| 76 | * and so we have to save the next-to-last group too for its above-context.) |
| 77 | * We could do this most simply by copying data around in our buffer, but |
| 78 | * that'd be very slow. We can avoid copying any data by creating a rather |
| 79 | * strange pointer structure. Here's how it works. We allocate a workspace |
| 80 | * consisting of M+2 row groups (where M = min_DCT_scaled_size is the number |
| 81 | * of row groups per iMCU row). We create two sets of redundant pointers to |
| 82 | * the workspace. Labeling the physical row groups 0 to M+1, the synthesized |
| 83 | * pointer lists look like this: |
| 84 | * M+1 M-1 |
| 85 | * master pointer --> 0 master pointer --> 0 |
| 86 | * 1 1 |
| 87 | * ... ... |
| 88 | * M-3 M-3 |
| 89 | * M-2 M |
| 90 | * M-1 M+1 |
| 91 | * M M-2 |
| 92 | * M+1 M-1 |
| 93 | * 0 0 |
| 94 | * We read alternate iMCU rows using each master pointer; thus the last two |
| 95 | * row groups of the previous iMCU row remain un-overwritten in the workspace. |
| 96 | * The pointer lists are set up so that the required context rows appear to |
| 97 | * be adjacent to the proper places when we pass the pointer lists to the |
| 98 | * upsampler. |
| 99 | * |
| 100 | * The above pictures describe the normal state of the pointer lists. |
| 101 | * At top and bottom of the image, we diddle the pointer lists to duplicate |
| 102 | * the first or last sample row as necessary (this is cheaper than copying |
| 103 | * sample rows around). |
| 104 | * |
| 105 | * This scheme breaks down if M < 2, ie, min_DCT_scaled_size is 1. In that |
| 106 | * situation each iMCU row provides only one row group so the buffering logic |
| 107 | * must be different (eg, we must read two iMCU rows before we can emit the |
| 108 | * first row group). For now, we simply do not support providing context |
| 109 | * rows when min_DCT_scaled_size is 1. That combination seems unlikely to |
| 110 | * be worth providing --- if someone wants a 1/8th-size preview, they probably |
| 111 | * want it quick and dirty, so a context-free upsampler is sufficient. |
| 112 | */ |
| 113 | |
| 114 | |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 115 | /* Forward declarations */ |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 116 | METHODDEF(void) process_data_simple_main(j_decompress_ptr cinfo, |
| 117 | JSAMPARRAY output_buf, |
| 118 | JDIMENSION *out_row_ctr, |
| 119 | JDIMENSION out_rows_avail); |
| 120 | METHODDEF(void) process_data_context_main(j_decompress_ptr cinfo, |
| 121 | JSAMPARRAY output_buf, |
| 122 | JDIMENSION *out_row_ctr, |
| 123 | JDIMENSION out_rows_avail); |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 124 | #ifdef QUANT_2PASS_SUPPORTED |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 125 | METHODDEF(void) process_data_crank_post(j_decompress_ptr cinfo, |
| 126 | JSAMPARRAY output_buf, |
| 127 | JDIMENSION *out_row_ctr, |
| 128 | JDIMENSION out_rows_avail); |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 129 | #endif |
| 130 | |
| 131 | |
| 132 | LOCAL(void) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 133 | alloc_funny_pointers(j_decompress_ptr cinfo) |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 134 | /* Allocate space for the funny pointer lists. |
| 135 | * This is done only once, not once per pass. |
| 136 | */ |
| 137 | { |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 138 | my_main_ptr main_ptr = (my_main_ptr)cinfo->main; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 139 | int ci, rgroup; |
hbono@chromium.org | 9862697 | 2011-08-03 03:13:08 +0000 | [diff] [blame] | 140 | int M = cinfo->_min_DCT_scaled_size; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 141 | jpeg_component_info *compptr; |
| 142 | JSAMPARRAY xbuf; |
| 143 | |
| 144 | /* Get top-level space for component array pointers. |
| 145 | * We alloc both arrays with one call to save a few cycles. |
| 146 | */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 147 | main_ptr->xbuffer[0] = (JSAMPIMAGE) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 148 | (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE, |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 149 | cinfo->num_components * 2 * sizeof(JSAMPARRAY)); |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 150 | main_ptr->xbuffer[1] = main_ptr->xbuffer[0] + cinfo->num_components; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 151 | |
| 152 | for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; |
| 153 | ci++, compptr++) { |
hbono@chromium.org | 9862697 | 2011-08-03 03:13:08 +0000 | [diff] [blame] | 154 | rgroup = (compptr->v_samp_factor * compptr->_DCT_scaled_size) / |
| 155 | cinfo->_min_DCT_scaled_size; /* height of a row group of component */ |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 156 | /* Get space for pointer lists --- M+4 row groups in each list. |
| 157 | * We alloc both pointer lists with one call to save a few cycles. |
| 158 | */ |
| 159 | xbuf = (JSAMPARRAY) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 160 | (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE, |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 161 | 2 * (rgroup * (M + 4)) * sizeof(JSAMPROW)); |
| 162 | xbuf += rgroup; /* want one row group at negative offsets */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 163 | main_ptr->xbuffer[0][ci] = xbuf; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 164 | xbuf += rgroup * (M + 4); |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 165 | main_ptr->xbuffer[1][ci] = xbuf; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 166 | } |
| 167 | } |
| 168 | |
| 169 | |
| 170 | LOCAL(void) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 171 | make_funny_pointers(j_decompress_ptr cinfo) |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 172 | /* Create the funny pointer lists discussed in the comments above. |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 173 | * The actual workspace is already allocated (in main_ptr->buffer), |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 174 | * and the space for the pointer lists is allocated too. |
| 175 | * This routine just fills in the curiously ordered lists. |
| 176 | * This will be repeated at the beginning of each pass. |
| 177 | */ |
| 178 | { |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 179 | my_main_ptr main_ptr = (my_main_ptr)cinfo->main; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 180 | int ci, i, rgroup; |
hbono@chromium.org | 9862697 | 2011-08-03 03:13:08 +0000 | [diff] [blame] | 181 | int M = cinfo->_min_DCT_scaled_size; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 182 | jpeg_component_info *compptr; |
| 183 | JSAMPARRAY buf, xbuf0, xbuf1; |
| 184 | |
| 185 | for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; |
| 186 | ci++, compptr++) { |
hbono@chromium.org | 9862697 | 2011-08-03 03:13:08 +0000 | [diff] [blame] | 187 | rgroup = (compptr->v_samp_factor * compptr->_DCT_scaled_size) / |
| 188 | cinfo->_min_DCT_scaled_size; /* height of a row group of component */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 189 | xbuf0 = main_ptr->xbuffer[0][ci]; |
| 190 | xbuf1 = main_ptr->xbuffer[1][ci]; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 191 | /* First copy the workspace pointers as-is */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 192 | buf = main_ptr->buffer[ci]; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 193 | for (i = 0; i < rgroup * (M + 2); i++) { |
| 194 | xbuf0[i] = xbuf1[i] = buf[i]; |
| 195 | } |
| 196 | /* In the second list, put the last four row groups in swapped order */ |
| 197 | for (i = 0; i < rgroup * 2; i++) { |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 198 | xbuf1[rgroup * (M - 2) + i] = buf[rgroup * M + i]; |
| 199 | xbuf1[rgroup * M + i] = buf[rgroup * (M - 2) + i]; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 200 | } |
| 201 | /* The wraparound pointers at top and bottom will be filled later |
| 202 | * (see set_wraparound_pointers, below). Initially we want the "above" |
| 203 | * pointers to duplicate the first actual data line. This only needs |
| 204 | * to happen in xbuffer[0]. |
| 205 | */ |
| 206 | for (i = 0; i < rgroup; i++) { |
| 207 | xbuf0[i - rgroup] = xbuf0[0]; |
| 208 | } |
| 209 | } |
| 210 | } |
| 211 | |
| 212 | |
| 213 | LOCAL(void) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 214 | set_bottom_pointers(j_decompress_ptr cinfo) |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 215 | /* Change the pointer lists to duplicate the last sample row at the bottom |
| 216 | * of the image. whichptr indicates which xbuffer holds the final iMCU row. |
| 217 | * Also sets rowgroups_avail to indicate number of nondummy row groups in row. |
| 218 | */ |
| 219 | { |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 220 | my_main_ptr main_ptr = (my_main_ptr)cinfo->main; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 221 | int ci, i, rgroup, iMCUheight, rows_left; |
| 222 | jpeg_component_info *compptr; |
| 223 | JSAMPARRAY xbuf; |
| 224 | |
| 225 | for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; |
| 226 | ci++, compptr++) { |
| 227 | /* Count sample rows in one iMCU row and in one row group */ |
hbono@chromium.org | 9862697 | 2011-08-03 03:13:08 +0000 | [diff] [blame] | 228 | iMCUheight = compptr->v_samp_factor * compptr->_DCT_scaled_size; |
| 229 | rgroup = iMCUheight / cinfo->_min_DCT_scaled_size; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 230 | /* Count nondummy sample rows remaining for this component */ |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 231 | rows_left = (int)(compptr->downsampled_height % (JDIMENSION)iMCUheight); |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 232 | if (rows_left == 0) rows_left = iMCUheight; |
| 233 | /* Count nondummy row groups. Should get same answer for each component, |
| 234 | * so we need only do it once. |
| 235 | */ |
| 236 | if (ci == 0) { |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 237 | main_ptr->rowgroups_avail = (JDIMENSION)((rows_left - 1) / rgroup + 1); |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 238 | } |
| 239 | /* Duplicate the last real sample row rgroup*2 times; this pads out the |
| 240 | * last partial rowgroup and ensures at least one full rowgroup of context. |
| 241 | */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 242 | xbuf = main_ptr->xbuffer[main_ptr->whichptr][ci]; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 243 | for (i = 0; i < rgroup * 2; i++) { |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 244 | xbuf[rows_left + i] = xbuf[rows_left - 1]; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 245 | } |
| 246 | } |
| 247 | } |
| 248 | |
| 249 | |
| 250 | /* |
| 251 | * Initialize for a processing pass. |
| 252 | */ |
| 253 | |
| 254 | METHODDEF(void) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 255 | start_pass_main(j_decompress_ptr cinfo, J_BUF_MODE pass_mode) |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 256 | { |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 257 | my_main_ptr main_ptr = (my_main_ptr)cinfo->main; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 258 | |
| 259 | switch (pass_mode) { |
| 260 | case JBUF_PASS_THRU: |
| 261 | if (cinfo->upsample->need_context_rows) { |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 262 | main_ptr->pub.process_data = process_data_context_main; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 263 | make_funny_pointers(cinfo); /* Create the xbuffer[] lists */ |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 264 | main_ptr->whichptr = 0; /* Read first iMCU row into xbuffer[0] */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 265 | main_ptr->context_state = CTX_PREPARE_FOR_IMCU; |
| 266 | main_ptr->iMCU_row_ctr = 0; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 267 | } else { |
| 268 | /* Simple case with no context needed */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 269 | main_ptr->pub.process_data = process_data_simple_main; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 270 | } |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 271 | main_ptr->buffer_full = FALSE; /* Mark buffer empty */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 272 | main_ptr->rowgroup_ctr = 0; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 273 | break; |
| 274 | #ifdef QUANT_2PASS_SUPPORTED |
| 275 | case JBUF_CRANK_DEST: |
| 276 | /* For last pass of 2-pass quantization, just crank the postprocessor */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 277 | main_ptr->pub.process_data = process_data_crank_post; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 278 | break; |
| 279 | #endif |
| 280 | default: |
| 281 | ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); |
| 282 | break; |
| 283 | } |
| 284 | } |
| 285 | |
| 286 | |
| 287 | /* |
| 288 | * Process some data. |
| 289 | * This handles the simple case where no context is required. |
| 290 | */ |
| 291 | |
| 292 | METHODDEF(void) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 293 | process_data_simple_main(j_decompress_ptr cinfo, JSAMPARRAY output_buf, |
| 294 | JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail) |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 295 | { |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 296 | my_main_ptr main_ptr = (my_main_ptr)cinfo->main; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 297 | JDIMENSION rowgroups_avail; |
| 298 | |
| 299 | /* Read input data if we haven't filled the main buffer yet */ |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 300 | if (!main_ptr->buffer_full) { |
| 301 | if (!(*cinfo->coef->decompress_data) (cinfo, main_ptr->buffer)) |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 302 | return; /* suspension forced, can do nothing more */ |
| 303 | main_ptr->buffer_full = TRUE; /* OK, we have an iMCU row to work with */ |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 304 | } |
| 305 | |
| 306 | /* There are always min_DCT_scaled_size row groups in an iMCU row. */ |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 307 | rowgroups_avail = (JDIMENSION)cinfo->_min_DCT_scaled_size; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 308 | /* Note: at the bottom of the image, we may pass extra garbage row groups |
| 309 | * to the postprocessor. The postprocessor has to check for bottom |
| 310 | * of image anyway (at row resolution), so no point in us doing it too. |
| 311 | */ |
| 312 | |
| 313 | /* Feed the postprocessor */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 314 | (*cinfo->post->post_process_data) (cinfo, main_ptr->buffer, |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 315 | &main_ptr->rowgroup_ctr, rowgroups_avail, |
| 316 | output_buf, out_row_ctr, out_rows_avail); |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 317 | |
| 318 | /* Has postprocessor consumed all the data yet? If so, mark buffer empty */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 319 | if (main_ptr->rowgroup_ctr >= rowgroups_avail) { |
| 320 | main_ptr->buffer_full = FALSE; |
| 321 | main_ptr->rowgroup_ctr = 0; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 322 | } |
| 323 | } |
| 324 | |
| 325 | |
| 326 | /* |
| 327 | * Process some data. |
| 328 | * This handles the case where context rows must be provided. |
| 329 | */ |
| 330 | |
| 331 | METHODDEF(void) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 332 | process_data_context_main(j_decompress_ptr cinfo, JSAMPARRAY output_buf, |
| 333 | JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail) |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 334 | { |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 335 | my_main_ptr main_ptr = (my_main_ptr)cinfo->main; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 336 | |
| 337 | /* Read input data if we haven't filled the main buffer yet */ |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 338 | if (!main_ptr->buffer_full) { |
| 339 | if (!(*cinfo->coef->decompress_data) (cinfo, |
| 340 | main_ptr->xbuffer[main_ptr->whichptr])) |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 341 | return; /* suspension forced, can do nothing more */ |
| 342 | main_ptr->buffer_full = TRUE; /* OK, we have an iMCU row to work with */ |
| 343 | main_ptr->iMCU_row_ctr++; /* count rows received */ |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 344 | } |
| 345 | |
| 346 | /* Postprocessor typically will not swallow all the input data it is handed |
| 347 | * in one call (due to filling the output buffer first). Must be prepared |
| 348 | * to exit and restart. This switch lets us keep track of how far we got. |
| 349 | * Note that each case falls through to the next on successful completion. |
| 350 | */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 351 | switch (main_ptr->context_state) { |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 352 | case CTX_POSTPONED_ROW: |
| 353 | /* Call postprocessor using previously set pointers for postponed row */ |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 354 | (*cinfo->post->post_process_data) (cinfo, |
| 355 | main_ptr->xbuffer[main_ptr->whichptr], |
| 356 | &main_ptr->rowgroup_ctr, |
| 357 | main_ptr->rowgroups_avail, output_buf, |
| 358 | out_row_ctr, out_rows_avail); |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 359 | if (main_ptr->rowgroup_ctr < main_ptr->rowgroups_avail) |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 360 | return; /* Need to suspend */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 361 | main_ptr->context_state = CTX_PREPARE_FOR_IMCU; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 362 | if (*out_row_ctr >= out_rows_avail) |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 363 | return; /* Postprocessor exactly filled output buf */ |
Peter Kasting | 2eb7e20 | 2021-07-09 07:13:34 -0700 | [diff] [blame] | 364 | FALLTHROUGH /*FALLTHROUGH*/ |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 365 | case CTX_PREPARE_FOR_IMCU: |
| 366 | /* Prepare to process first M-1 row groups of this iMCU row */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 367 | main_ptr->rowgroup_ctr = 0; |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 368 | main_ptr->rowgroups_avail = (JDIMENSION)(cinfo->_min_DCT_scaled_size - 1); |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 369 | /* Check for bottom of image: if so, tweak pointers to "duplicate" |
| 370 | * the last sample row, and adjust rowgroups_avail to ignore padding rows. |
| 371 | */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 372 | if (main_ptr->iMCU_row_ctr == cinfo->total_iMCU_rows) |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 373 | set_bottom_pointers(cinfo); |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 374 | main_ptr->context_state = CTX_PROCESS_IMCU; |
Peter Kasting | 2eb7e20 | 2021-07-09 07:13:34 -0700 | [diff] [blame] | 375 | FALLTHROUGH /*FALLTHROUGH*/ |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 376 | case CTX_PROCESS_IMCU: |
| 377 | /* Call postprocessor using previously set pointers */ |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 378 | (*cinfo->post->post_process_data) (cinfo, |
| 379 | main_ptr->xbuffer[main_ptr->whichptr], |
| 380 | &main_ptr->rowgroup_ctr, |
| 381 | main_ptr->rowgroups_avail, output_buf, |
| 382 | out_row_ctr, out_rows_avail); |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 383 | if (main_ptr->rowgroup_ctr < main_ptr->rowgroups_avail) |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 384 | return; /* Need to suspend */ |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 385 | /* After the first iMCU, change wraparound pointers to normal state */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 386 | if (main_ptr->iMCU_row_ctr == 1) |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 387 | set_wraparound_pointers(cinfo); |
| 388 | /* Prepare to load new iMCU row using other xbuffer list */ |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 389 | main_ptr->whichptr ^= 1; /* 0=>1 or 1=>0 */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 390 | main_ptr->buffer_full = FALSE; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 391 | /* Still need to process last row group of this iMCU row, */ |
| 392 | /* which is saved at index M+1 of the other xbuffer */ |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 393 | main_ptr->rowgroup_ctr = (JDIMENSION)(cinfo->_min_DCT_scaled_size + 1); |
| 394 | main_ptr->rowgroups_avail = (JDIMENSION)(cinfo->_min_DCT_scaled_size + 2); |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 395 | main_ptr->context_state = CTX_POSTPONED_ROW; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 396 | } |
| 397 | } |
| 398 | |
| 399 | |
| 400 | /* |
| 401 | * Process some data. |
| 402 | * Final pass of two-pass quantization: just call the postprocessor. |
| 403 | * Source data will be the postprocessor controller's internal buffer. |
| 404 | */ |
| 405 | |
| 406 | #ifdef QUANT_2PASS_SUPPORTED |
| 407 | |
| 408 | METHODDEF(void) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 409 | process_data_crank_post(j_decompress_ptr cinfo, JSAMPARRAY output_buf, |
| 410 | JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail) |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 411 | { |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 412 | (*cinfo->post->post_process_data) (cinfo, (JSAMPIMAGE)NULL, |
| 413 | (JDIMENSION *)NULL, (JDIMENSION)0, |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 414 | output_buf, out_row_ctr, out_rows_avail); |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 415 | } |
| 416 | |
| 417 | #endif /* QUANT_2PASS_SUPPORTED */ |
| 418 | |
| 419 | |
| 420 | /* |
| 421 | * Initialize main buffer controller. |
| 422 | */ |
| 423 | |
| 424 | GLOBAL(void) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 425 | jinit_d_main_controller(j_decompress_ptr cinfo, boolean need_full_buffer) |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 426 | { |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 427 | my_main_ptr main_ptr; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 428 | int ci, rgroup, ngroups; |
| 429 | jpeg_component_info *compptr; |
| 430 | |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 431 | main_ptr = (my_main_ptr) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 432 | (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE, |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 433 | sizeof(my_main_controller)); |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 434 | cinfo->main = (struct jpeg_d_main_controller *)main_ptr; |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 435 | main_ptr->pub.start_pass = start_pass_main; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 436 | |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 437 | if (need_full_buffer) /* shouldn't happen */ |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 438 | ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); |
| 439 | |
| 440 | /* Allocate the workspace. |
| 441 | * ngroups is the number of row groups we need. |
| 442 | */ |
| 443 | if (cinfo->upsample->need_context_rows) { |
hbono@chromium.org | 9862697 | 2011-08-03 03:13:08 +0000 | [diff] [blame] | 444 | if (cinfo->_min_DCT_scaled_size < 2) /* unsupported, see comments above */ |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 445 | ERREXIT(cinfo, JERR_NOTIMPL); |
| 446 | alloc_funny_pointers(cinfo); /* Alloc space for xbuffer[] lists */ |
hbono@chromium.org | 9862697 | 2011-08-03 03:13:08 +0000 | [diff] [blame] | 447 | ngroups = cinfo->_min_DCT_scaled_size + 2; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 448 | } else { |
hbono@chromium.org | 9862697 | 2011-08-03 03:13:08 +0000 | [diff] [blame] | 449 | ngroups = cinfo->_min_DCT_scaled_size; |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 450 | } |
| 451 | |
| 452 | for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; |
| 453 | ci++, compptr++) { |
hbono@chromium.org | 9862697 | 2011-08-03 03:13:08 +0000 | [diff] [blame] | 454 | rgroup = (compptr->v_samp_factor * compptr->_DCT_scaled_size) / |
| 455 | cinfo->_min_DCT_scaled_size; /* height of a row group of component */ |
hbono@chromium.org | c6beb74 | 2011-11-29 05:16:26 +0000 | [diff] [blame] | 456 | main_ptr->buffer[ci] = (*cinfo->mem->alloc_sarray) |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 457 | ((j_common_ptr)cinfo, JPOOL_IMAGE, |
Tom Hudson | 0d47d2d | 2016-05-04 13:22:56 -0400 | [diff] [blame] | 458 | compptr->width_in_blocks * compptr->_DCT_scaled_size, |
Chris Blume | cca8c4d | 2019-03-01 01:09:50 -0800 | [diff] [blame] | 459 | (JDIMENSION)(rgroup * ngroups)); |
hbono@chromium.org | f0c4f33 | 2010-11-01 05:14:55 +0000 | [diff] [blame] | 460 | } |
| 461 | } |