Doxygen Source Code Documentation
jcsample.c File Reference
#include "jinclude.h"
#include "jpeglib.h"
Go to the source code of this file.
Define Documentation
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Definition at line 48 of file jcsample.c. |
Typedef Documentation
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Definition at line 67 of file jcsample.c. |
Function Documentation
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Definition at line 87 of file jcsample.c. References JDIMENSION, JSAMPARRAY, JSAMPLE, JSAMPROW, num_rows, and pixval. Referenced by fullsize_downsample(), fullsize_smooth_downsample(), h2v1_downsample(), h2v2_downsample(), h2v2_smooth_downsample(), and int_downsample().
00089 { 00090 register JSAMPROW ptr; 00091 register JSAMPLE pixval; 00092 register int count; 00093 int row; 00094 int numcols = (int) (output_cols - input_cols); 00095 00096 if (numcols > 0) { 00097 for (row = 0; row < num_rows; row++) { 00098 ptr = image_data[row] + input_cols; 00099 pixval = ptr[-1]; /* don't need GETJSAMPLE() here */ 00100 for (count = numcols; count > 0; count--) 00101 *ptr++ = pixval; 00102 } 00103 } 00104 } |
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Definition at line 187 of file jcsample.c. References compptr, expand_right_edge(), jpeg_compress_struct::image_width, jcopy_sample_rows(), JSAMPARRAY, jpeg_compress_struct::max_v_samp_factor, and jpeg_component_info::width_in_blocks. Referenced by jinit_downsampler().
00189 { 00190 /* Copy the data */ 00191 jcopy_sample_rows(input_data, 0, output_data, 0, 00192 cinfo->max_v_samp_factor, cinfo->image_width); 00193 /* Edge-expand */ 00194 expand_right_edge(output_data, cinfo->max_v_samp_factor, 00195 cinfo->image_width, compptr->width_in_blocks * DCTSIZE); 00196 } |
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Definition at line 392 of file jcsample.c. References compptr, expand_right_edge(), GETJSAMPLE, jpeg_compress_struct::image_width, INT32, JDIMENSION, JSAMPARRAY, JSAMPROW, L, jpeg_compress_struct::max_v_samp_factor, jpeg_compress_struct::smoothing_factor, jpeg_component_info::v_samp_factor, and jpeg_component_info::width_in_blocks. Referenced by jinit_downsampler().
00394 { 00395 int outrow; 00396 JDIMENSION colctr; 00397 JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE; 00398 register JSAMPROW inptr, above_ptr, below_ptr, outptr; 00399 INT32 membersum, neighsum, memberscale, neighscale; 00400 int colsum, lastcolsum, nextcolsum; 00401 00402 /* Expand input data enough to let all the output samples be generated 00403 * by the standard loop. Special-casing padded output would be more 00404 * efficient. 00405 */ 00406 expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2, 00407 cinfo->image_width, output_cols); 00408 00409 /* Each of the eight neighbor pixels contributes a fraction SF to the 00410 * smoothed pixel, while the main pixel contributes (1-8*SF). In order 00411 * to use integer arithmetic, these factors are multiplied by 2^16 = 65536. 00412 * Also recall that SF = smoothing_factor / 1024. 00413 */ 00414 00415 memberscale = 65536L - cinfo->smoothing_factor * 512L; /* scaled 1-8*SF */ 00416 neighscale = cinfo->smoothing_factor * 64; /* scaled SF */ 00417 00418 for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) { 00419 outptr = output_data[outrow]; 00420 inptr = input_data[outrow]; 00421 above_ptr = input_data[outrow-1]; 00422 below_ptr = input_data[outrow+1]; 00423 00424 /* Special case for first column */ 00425 colsum = GETJSAMPLE(*above_ptr++) + GETJSAMPLE(*below_ptr++) + 00426 GETJSAMPLE(*inptr); 00427 membersum = GETJSAMPLE(*inptr++); 00428 nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) + 00429 GETJSAMPLE(*inptr); 00430 neighsum = colsum + (colsum - membersum) + nextcolsum; 00431 membersum = membersum * memberscale + neighsum * neighscale; 00432 *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16); 00433 lastcolsum = colsum; colsum = nextcolsum; 00434 00435 for (colctr = output_cols - 2; colctr > 0; colctr--) { 00436 membersum = GETJSAMPLE(*inptr++); 00437 above_ptr++; below_ptr++; 00438 nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) + 00439 GETJSAMPLE(*inptr); 00440 neighsum = lastcolsum + (colsum - membersum) + nextcolsum; 00441 membersum = membersum * memberscale + neighsum * neighscale; 00442 *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16); 00443 lastcolsum = colsum; colsum = nextcolsum; 00444 } 00445 00446 /* Special case for last column */ 00447 membersum = GETJSAMPLE(*inptr); 00448 neighsum = lastcolsum + (colsum - membersum) + colsum; 00449 membersum = membersum * memberscale + neighsum * neighscale; 00450 *outptr = (JSAMPLE) ((membersum + 32768) >> 16); 00451 00452 } 00453 } |
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Definition at line 212 of file jcsample.c. References compptr, expand_right_edge(), GETJSAMPLE, jpeg_compress_struct::image_width, JDIMENSION, JSAMPARRAY, JSAMPROW, jpeg_compress_struct::max_v_samp_factor, jpeg_component_info::v_samp_factor, and jpeg_component_info::width_in_blocks. Referenced by jinit_downsampler().
00214 { 00215 int outrow; 00216 JDIMENSION outcol; 00217 JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE; 00218 register JSAMPROW inptr, outptr; 00219 register int bias; 00220 00221 /* Expand input data enough to let all the output samples be generated 00222 * by the standard loop. Special-casing padded output would be more 00223 * efficient. 00224 */ 00225 expand_right_edge(input_data, cinfo->max_v_samp_factor, 00226 cinfo->image_width, output_cols * 2); 00227 00228 for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) { 00229 outptr = output_data[outrow]; 00230 inptr = input_data[outrow]; 00231 bias = 0; /* bias = 0,1,0,1,... for successive samples */ 00232 for (outcol = 0; outcol < output_cols; outcol++) { 00233 *outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr) + GETJSAMPLE(inptr[1]) 00234 + bias) >> 1); 00235 bias ^= 1; /* 0=>1, 1=>0 */ 00236 inptr += 2; 00237 } 00238 } 00239 } |
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Definition at line 249 of file jcsample.c. References compptr, expand_right_edge(), GETJSAMPLE, jpeg_compress_struct::image_width, JDIMENSION, JSAMPARRAY, JSAMPROW, jpeg_compress_struct::max_v_samp_factor, jpeg_component_info::v_samp_factor, and jpeg_component_info::width_in_blocks. Referenced by jinit_downsampler().
00251 { 00252 int inrow, outrow; 00253 JDIMENSION outcol; 00254 JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE; 00255 register JSAMPROW inptr0, inptr1, outptr; 00256 register int bias; 00257 00258 /* Expand input data enough to let all the output samples be generated 00259 * by the standard loop. Special-casing padded output would be more 00260 * efficient. 00261 */ 00262 expand_right_edge(input_data, cinfo->max_v_samp_factor, 00263 cinfo->image_width, output_cols * 2); 00264 00265 inrow = 0; 00266 for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) { 00267 outptr = output_data[outrow]; 00268 inptr0 = input_data[inrow]; 00269 inptr1 = input_data[inrow+1]; 00270 bias = 1; /* bias = 1,2,1,2,... for successive samples */ 00271 for (outcol = 0; outcol < output_cols; outcol++) { 00272 *outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) + 00273 GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]) 00274 + bias) >> 2); 00275 bias ^= 3; /* 1=>2, 2=>1 */ 00276 inptr0 += 2; inptr1 += 2; 00277 } 00278 inrow += 2; 00279 } 00280 } |
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Definition at line 292 of file jcsample.c. References compptr, expand_right_edge(), GETJSAMPLE, jpeg_compress_struct::image_width, INT32, JDIMENSION, JSAMPARRAY, JSAMPROW, jpeg_compress_struct::max_v_samp_factor, jpeg_compress_struct::smoothing_factor, jpeg_component_info::v_samp_factor, and jpeg_component_info::width_in_blocks. Referenced by jinit_downsampler().
00294 { 00295 int inrow, outrow; 00296 JDIMENSION colctr; 00297 JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE; 00298 register JSAMPROW inptr0, inptr1, above_ptr, below_ptr, outptr; 00299 INT32 membersum, neighsum, memberscale, neighscale; 00300 00301 /* Expand input data enough to let all the output samples be generated 00302 * by the standard loop. Special-casing padded output would be more 00303 * efficient. 00304 */ 00305 expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2, 00306 cinfo->image_width, output_cols * 2); 00307 00308 /* We don't bother to form the individual "smoothed" input pixel values; 00309 * we can directly compute the output which is the average of the four 00310 * smoothed values. Each of the four member pixels contributes a fraction 00311 * (1-8*SF) to its own smoothed image and a fraction SF to each of the three 00312 * other smoothed pixels, therefore a total fraction (1-5*SF)/4 to the final 00313 * output. The four corner-adjacent neighbor pixels contribute a fraction 00314 * SF to just one smoothed pixel, or SF/4 to the final output; while the 00315 * eight edge-adjacent neighbors contribute SF to each of two smoothed 00316 * pixels, or SF/2 overall. In order to use integer arithmetic, these 00317 * factors are scaled by 2^16 = 65536. 00318 * Also recall that SF = smoothing_factor / 1024. 00319 */ 00320 00321 memberscale = 16384 - cinfo->smoothing_factor * 80; /* scaled (1-5*SF)/4 */ 00322 neighscale = cinfo->smoothing_factor * 16; /* scaled SF/4 */ 00323 00324 inrow = 0; 00325 for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) { 00326 outptr = output_data[outrow]; 00327 inptr0 = input_data[inrow]; 00328 inptr1 = input_data[inrow+1]; 00329 above_ptr = input_data[inrow-1]; 00330 below_ptr = input_data[inrow+2]; 00331 00332 /* Special case for first column: pretend column -1 is same as column 0 */ 00333 membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) + 00334 GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]); 00335 neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) + 00336 GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) + 00337 GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[2]) + 00338 GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[2]); 00339 neighsum += neighsum; 00340 neighsum += GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[2]) + 00341 GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[2]); 00342 membersum = membersum * memberscale + neighsum * neighscale; 00343 *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16); 00344 inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2; 00345 00346 for (colctr = output_cols - 2; colctr > 0; colctr--) { 00347 /* sum of pixels directly mapped to this output element */ 00348 membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) + 00349 GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]); 00350 /* sum of edge-neighbor pixels */ 00351 neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) + 00352 GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) + 00353 GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[2]) + 00354 GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[2]); 00355 /* The edge-neighbors count twice as much as corner-neighbors */ 00356 neighsum += neighsum; 00357 /* Add in the corner-neighbors */ 00358 neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[2]) + 00359 GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[2]); 00360 /* form final output scaled up by 2^16 */ 00361 membersum = membersum * memberscale + neighsum * neighscale; 00362 /* round, descale and output it */ 00363 *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16); 00364 inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2; 00365 } 00366 00367 /* Special case for last column */ 00368 membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) + 00369 GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]); 00370 neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) + 00371 GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) + 00372 GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[1]) + 00373 GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[1]); 00374 neighsum += neighsum; 00375 neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[1]) + 00376 GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[1]); 00377 membersum = membersum * memberscale + neighsum * neighscale; 00378 *outptr = (JSAMPLE) ((membersum + 32768) >> 16); 00379 00380 inrow += 2; 00381 } 00382 } |
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Definition at line 140 of file jcsample.c. References compptr, expand_right_edge(), GETJSAMPLE, jpeg_component_info::h_samp_factor, jpeg_compress_struct::image_width, INT32, JDIMENSION, JSAMPARRAY, JSAMPROW, jpeg_compress_struct::max_h_samp_factor, jpeg_compress_struct::max_v_samp_factor, v, jpeg_component_info::v_samp_factor, and jpeg_component_info::width_in_blocks. Referenced by jinit_downsampler().
00142 { 00143 int inrow, outrow, h_expand, v_expand, numpix, numpix2, h, v; 00144 JDIMENSION outcol, outcol_h; /* outcol_h == outcol*h_expand */ 00145 JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE; 00146 JSAMPROW inptr, outptr; 00147 INT32 outvalue; 00148 00149 h_expand = cinfo->max_h_samp_factor / compptr->h_samp_factor; 00150 v_expand = cinfo->max_v_samp_factor / compptr->v_samp_factor; 00151 numpix = h_expand * v_expand; 00152 numpix2 = numpix/2; 00153 00154 /* Expand input data enough to let all the output samples be generated 00155 * by the standard loop. Special-casing padded output would be more 00156 * efficient. 00157 */ 00158 expand_right_edge(input_data, cinfo->max_v_samp_factor, 00159 cinfo->image_width, output_cols * h_expand); 00160 00161 inrow = 0; 00162 for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) { 00163 outptr = output_data[outrow]; 00164 for (outcol = 0, outcol_h = 0; outcol < output_cols; 00165 outcol++, outcol_h += h_expand) { 00166 outvalue = 0; 00167 for (v = 0; v < v_expand; v++) { 00168 inptr = input_data[inrow+v] + outcol_h; 00169 for (h = 0; h < h_expand; h++) { 00170 outvalue += (INT32) GETJSAMPLE(*inptr++); 00171 } 00172 } 00173 *outptr++ = (JSAMPLE) ((outvalue + numpix2) / numpix); 00174 } 00175 inrow += v_expand; 00176 } 00177 } |
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Definition at line 464 of file jcsample.c. References compptr, ERREXIT, fullsize_downsample(), fullsize_smooth_downsample(), h2v1_downsample(), h2v2_downsample(), h2v2_smooth_downsample(), jpeg_component_info::h_samp_factor, int_downsample(), JPOOL_IMAGE, JTRC_SMOOTH_NOTIMPL, jpeg_downsampler::need_context_rows, sep_downsample(), SIZEOF, start_pass_downsample(), TRACEMS, and jpeg_component_info::v_samp_factor. Referenced by jinit_compress_master().
00465 { 00466 my_downsample_ptr downsample; 00467 int ci; 00468 jpeg_component_info * compptr; 00469 boolean smoothok = TRUE; 00470 00471 downsample = (my_downsample_ptr) 00472 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, 00473 SIZEOF(my_downsampler)); 00474 cinfo->downsample = (struct jpeg_downsampler *) downsample; 00475 downsample->pub.start_pass = start_pass_downsample; 00476 downsample->pub.downsample = sep_downsample; 00477 downsample->pub.need_context_rows = FALSE; 00478 00479 if (cinfo->CCIR601_sampling) 00480 ERREXIT(cinfo, JERR_CCIR601_NOTIMPL); 00481 00482 /* Verify we can handle the sampling factors, and set up method pointers */ 00483 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; 00484 ci++, compptr++) { 00485 if (compptr->h_samp_factor == cinfo->max_h_samp_factor && 00486 compptr->v_samp_factor == cinfo->max_v_samp_factor) { 00487 #ifdef INPUT_SMOOTHING_SUPPORTED 00488 if (cinfo->smoothing_factor) { 00489 downsample->methods[ci] = fullsize_smooth_downsample; 00490 downsample->pub.need_context_rows = TRUE; 00491 } else 00492 #endif 00493 downsample->methods[ci] = fullsize_downsample; 00494 } else if (compptr->h_samp_factor * 2 == cinfo->max_h_samp_factor && 00495 compptr->v_samp_factor == cinfo->max_v_samp_factor) { 00496 smoothok = FALSE; 00497 downsample->methods[ci] = h2v1_downsample; 00498 } else if (compptr->h_samp_factor * 2 == cinfo->max_h_samp_factor && 00499 compptr->v_samp_factor * 2 == cinfo->max_v_samp_factor) { 00500 #ifdef INPUT_SMOOTHING_SUPPORTED 00501 if (cinfo->smoothing_factor) { 00502 downsample->methods[ci] = h2v2_smooth_downsample; 00503 downsample->pub.need_context_rows = TRUE; 00504 } else 00505 #endif 00506 downsample->methods[ci] = h2v2_downsample; 00507 } else if ((cinfo->max_h_samp_factor % compptr->h_samp_factor) == 0 && 00508 (cinfo->max_v_samp_factor % compptr->v_samp_factor) == 0) { 00509 smoothok = FALSE; 00510 downsample->methods[ci] = int_downsample; 00511 } else 00512 ERREXIT(cinfo, JERR_FRACT_SAMPLE_NOTIMPL); 00513 } 00514 00515 #ifdef INPUT_SMOOTHING_SUPPORTED 00516 if (cinfo->smoothing_factor && !smoothok) 00517 TRACEMS(cinfo, 0, JTRC_SMOOTH_NOTIMPL); 00518 #endif 00519 } |
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Definition at line 114 of file jcsample.c. References jpeg_compress_struct::comp_info, compptr, jpeg_compress_struct::downsample, JDIMENSION, JSAMPARRAY, JSAMPIMAGE, my_downsampler::methods, jpeg_compress_struct::num_components, and jpeg_component_info::v_samp_factor. Referenced by jinit_downsampler().
00117 { 00118 my_downsample_ptr downsample = (my_downsample_ptr) cinfo->downsample; 00119 int ci; 00120 jpeg_component_info * compptr; 00121 JSAMPARRAY in_ptr, out_ptr; 00122 00123 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; 00124 ci++, compptr++) { 00125 in_ptr = input_buf[ci] + in_row_index; 00126 out_ptr = output_buf[ci] + (out_row_group_index * compptr->v_samp_factor); 00127 (*downsample->methods[ci]) (cinfo, compptr, in_ptr, out_ptr); 00128 } 00129 } |
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Definition at line 75 of file jcsample.c. Referenced by jinit_downsampler().
00076 {
00077 /* no work for now */
00078 }
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