tools/skdiff_main.cpp

   1 #include "SkColorPriv.h"
   2 #include "SkImageDecoder.h"
   3 #include "SkImageEncoder.h"
   4 #include "SkOSFile.h"
   5 #include "SkStream.h"
   6 #include "SkTDArray.h"
   7 #include "SkTemplates.h"
   8 #include "SkTime.h"
   9 #include "SkTSearch.h"
  10 #include "SkTypes.h"
  11
  12 /**
  13  * skdiff
  14  *
  15  * Given three directory names, expects to find identically-named files in
  16  * each of the first two; the first are treated as a set of baseline,
  17  * the second a set of variant images, and a diff image is written into the
  18  * third directory for each pair.
  19  * Creates an index.html in the current working directory to compare each
  20  * pair that does not match exactly.
  21  * Does *not* recursively descend directories.
  22  */
  23
  24 struct DiffRecord {
  25     DiffRecord (const SkString filename)
  26         : fFilename (filename)
  27         , fMetricValue (0)
  28         , fAverageMismatchR (0)
  29         , fAverageMismatchG (0)
  30         , fAverageMismatchB (0)
  31         , fMaxMismatchR (0)
  32         , fMaxMismatchG (0)
  33         , fMaxMismatchB (0) { };
  34
  35     SkString fFilename;
  36
  37     SkBitmap fBaseBitmap;
  38     SkBitmap fComparisonBitmap;
  39     SkBitmap fDifferenceBitmap;
  40
  41     /// Arbitrary floating-point metric to be used to sort images from most
  42     /// to least different from baseline; values of 0 will be omitted from the
  43     /// summary webpage.
  44     float fMetricValue;
  45
  46     float fAverageMismatchR;
  47     float fAverageMismatchG;
  48     float fAverageMismatchB;
  49
  50     uint32_t fMaxMismatchR;
  51     uint32_t fMaxMismatchG;
  52     uint32_t fMaxMismatchB;
  53 };
  54
  55 typedef SkTDArray<DiffRecord*> RecordArray;
  56
  57 /// Comparison routine for qsort;  sorts by fMetricValue
  58 /// from largest to smallest.
  59 static int compare_diff_metrics (DiffRecord** lhs, DiffRecord** rhs) {
  60     if ((*lhs)->fMetricValue < (*rhs)->fMetricValue) {
  61         return 1;
  62     }
  63     if ((*rhs)->fMetricValue < (*lhs)->fMetricValue) {
  64         return -1;
  65     }
  66     return 0;
  67 }
  68
  69 #define MAX2(a,b) (((b) < (a)) ? (a) : (b))
  70 #define MAX3(a,b,c) (((b) < (a)) ? MAX2((a), (c)) : MAX2((b), (c)))
  71 /// Comparison routine for qsort;  sorts by max(fAverageMismatch{RGB})
  72 /// from largest to smallest.
  73 static int compare_diff_mean_mismatches (DiffRecord** lhs, DiffRecord** rhs) {
  74     float leftValue = MAX3((*lhs)->fAverageMismatchR,
  75                            (*lhs)->fAverageMismatchG,
  76                            (*lhs)->fAverageMismatchB);
  77     float rightValue = MAX3((*rhs)->fAverageMismatchR,
  78                             (*rhs)->fAverageMismatchG,
  79                             (*rhs)->fAverageMismatchB);
  80     if (leftValue < rightValue) {
  81         return 1;
  82     }
  83     if (rightValue < leftValue) {
  84         return -1;
  85     }
  86     return 0;
  87 }
  88
  89 /// Comparison routine for qsort;  sorts by max(fMaxMismatch{RGB})
  90 /// from largest to smallest.
  91 static int compare_diff_max_mismatches (DiffRecord** lhs, DiffRecord** rhs) {
  92     float leftValue = MAX3((*lhs)->fMaxMismatchR,
  93                            (*lhs)->fMaxMismatchG,
  94                            (*lhs)->fMaxMismatchB);
  95     float rightValue = MAX3((*rhs)->fMaxMismatchR,
  96                             (*rhs)->fMaxMismatchG,
  97                             (*rhs)->fMaxMismatchB);
  98     if (leftValue < rightValue) {
  99         return 1;
 100     }
 101     if (rightValue < leftValue) {
 102         return -1;
 103     }
 104     return compare_diff_mean_mismatches(lhs, rhs);
 105 }
 106
 107
 108
 109 /// Parameterized routine to compute the color of a pixel in a difference image.
 110 typedef SkPMColor (*DiffMetricProc)(SkPMColor, SkPMColor);
 111
 112 static bool get_bitmaps (DiffRecord* diffRecord,
 113                          const SkString& baseDir,
 114                          const SkString& comparisonDir) {
 115     SkString comparePath (comparisonDir);
 116     comparePath.append(diffRecord->fFilename);
 117     SkFILEStream compareStream(comparePath.c_str());
 118     if (!compareStream.isValid()) {
 119         SkDebugf("WARNING: couldn't open comparison file <%s>\n",
 120                  comparePath.c_str());
 121         return false;
 122     }
 123
 124     SkString basePath (baseDir);
 125     basePath.append(diffRecord->fFilename);
 126     SkFILEStream baseStream(basePath.c_str());
 127     if (!baseStream.isValid()) {
 128         SkDebugf("ERROR: couldn't open base file <%s>\n",
 129                  basePath.c_str());
 130         return false;
 131     }
 132
 133     SkImageDecoder* codec = SkImageDecoder::Factory(&baseStream);
 134     if (NULL == codec) {
 135         SkDebugf("ERROR: no codec found for <%s>\n",
 136                  basePath.c_str());
 137         return false;
 138     }
 139
 140     SkAutoTDelete<SkImageDecoder> ad(codec);
 141
 142     baseStream.rewind();
 143     if (!codec->decode(&baseStream, &diffRecord->fBaseBitmap,
 144                        SkBitmap::kARGB_8888_Config,
 145                        SkImageDecoder::kDecodePixels_Mode)) {
 146         SkDebugf("ERROR: codec failed for <%s>\n",
 147                  basePath.c_str());
 148         return false;
 149     }
 150
 151     if (!codec->decode(&compareStream, &diffRecord->fComparisonBitmap,
 152                        SkBitmap::kARGB_8888_Config,
 153                        SkImageDecoder::kDecodePixels_Mode)) {
 154         SkDebugf("ERROR: codec failed for <%s>\n",
 155                  comparePath.c_str());
 156         return false;
 157     }
 158
 159     return true;
 160 }
 161
 162 // from gm - thanks to PNG, we need to force all pixels 100% opaque
 163 static void force_all_opaque(const SkBitmap& bitmap) {
 164    SkAutoLockPixels lock(bitmap);
 165    for (int y = 0; y < bitmap.height(); y++) {
 166        for (int x = 0; x < bitmap.width(); x++) {
 167            *bitmap.getAddr32(x, y) |= (SK_A32_MASK << SK_A32_SHIFT);
 168        }
 169    }
 170 }
 171
 172 // from gm
 173 static bool write_bitmap(const SkString& path, const SkBitmap& bitmap) {
 174     SkBitmap copy;
 175     bitmap.copyTo(&copy, SkBitmap::kARGB_8888_Config);
 176     force_all_opaque(copy);
 177     return SkImageEncoder::EncodeFile(path.c_str(), copy,
 178                                       SkImageEncoder::kPNG_Type, 100);
 179 }
 180
 181 // from gm
 182 static inline SkPMColor compute_diff_pmcolor(SkPMColor c0, SkPMColor c1) {
 183     int dr = SkGetPackedR32(c0) - SkGetPackedR32(c1);
 184     int dg = SkGetPackedG32(c0) - SkGetPackedG32(c1);
 185     int db = SkGetPackedB32(c0) - SkGetPackedB32(c1);
 186
 187     return SkPackARGB32(0xFF, SkAbs32(dr), SkAbs32(dg), SkAbs32(db));
 188 }
 189
 190 /// Returns white on every pixel so that differences jump out at you;
 191 /// makes it easy to spot areas of difference that are in the least-significant
 192 /// bits.
 193 static inline SkPMColor compute_diff_white(SkPMColor c0, SkPMColor c1) {
 194     return SkPackARGB32(0xFF, 0xFF, 0xFF, 0xFF);
 195 }
 196
 197 static inline bool colors_match_thresholded(SkPMColor c0, SkPMColor c1,
 198                                             const int threshold) {
 199     int da = SkGetPackedA32(c0) - SkGetPackedA32(c1);
 200     int dr = SkGetPackedR32(c0) - SkGetPackedR32(c1);
 201     int dg = SkGetPackedG32(c0) - SkGetPackedG32(c1);
 202     int db = SkGetPackedB32(c0) - SkGetPackedB32(c1);
 203
 204     return ((SkAbs32(da) <= threshold) &&
 205             (SkAbs32(dr) <= threshold) &&
 206             (SkAbs32(dg) <= threshold) &&
 207             (SkAbs32(db) <= threshold));
 208 }
 209
 210 // based on gm
 211 static void compute_diff(DiffRecord* dr,
 212                          DiffMetricProc diffFunction,
 213                          const int colorThreshold) {
 214     SkAutoLockPixels alp(dr->fDifferenceBitmap);
 215
 216     const int w = dr->fComparisonBitmap.width();
 217     const int h = dr->fComparisonBitmap.height();
 218     int mismatchedPixels = 0;
 219     int totalMismatchR = 0;
 220     int totalMismatchG = 0;
 221     int totalMismatchB = 0;
 222     for (int y = 0; y < h; y++) {
 223         for (int x = 0; x < w; x++) {
 224             SkPMColor c0 = *dr->fBaseBitmap.getAddr32(x, y);
 225             SkPMColor c1 = *dr->fComparisonBitmap.getAddr32(x, y);
 226             SkPMColor d = 0;
 227             d = diffFunction(c0, c1);
 228             totalMismatchR += SkGetPackedR32(d);
 229             totalMismatchG += SkGetPackedG32(d);
 230             totalMismatchB += SkGetPackedB32(d);
 231             if (SkGetPackedR32(d) > dr->fMaxMismatchR) {
 232                 dr->fMaxMismatchR = SkGetPackedR32(d);
 233             }
 234             if (SkGetPackedG32(d) > dr->fMaxMismatchG) {
 235                 dr->fMaxMismatchG = SkGetPackedG32(d);
 236             }
 237             if (SkGetPackedB32(d) > dr->fMaxMismatchB) {
 238                 dr->fMaxMismatchB = SkGetPackedB32(d);
 239             }
 240             if (!colors_match_thresholded(c0, c1, colorThreshold)) {
 241                 mismatchedPixels++;
 242                 *dr->fDifferenceBitmap.getAddr32(x, y) = d;
 243             } else {
 244                 *dr->fDifferenceBitmap.getAddr32(x, y) = 0;
 245             }
 246         }
 247     }
 248     dr->fMetricValue = ((float) mismatchedPixels) / (w * h);
 249     dr->fAverageMismatchR = ((float) totalMismatchR) / (w * h);
 250     dr->fAverageMismatchG = ((float) totalMismatchG) / (w * h);
 251     dr->fAverageMismatchB = ((float) totalMismatchB) / (w * h);
 252 }
 253
 254 /// Creates difference images, returns the number that have a 0 metric.
 255 static int create_diff_images (DiffMetricProc dmp,
 256                                SkQSortCompareProc scp,
 257                                const int colorThreshold,
 258                                RecordArray* differences,
 259                                const SkString& baseDir,
 260                                const SkString& comparisonDir,
 261                                const SkString& outputDir) {
 262
 263     //@todo thudson 19 Apr 2011
 264     // this lets us know about files in baseDir not in compareDir, but it
 265     // doesn't detect files in compareDir not in baseDir. Doing that
 266     // efficiently seems to imply iterating through both directories to
 267     // create a merged list, and then attempting to process every entry
 268     // in that list?
 269
 270     SkOSFile::Iter baseIterator (baseDir.c_str());
 271     SkString filename;
 272     int matchCount = 0;
 273     while (baseIterator.next(&filename)) {
 274         DiffRecord * drp = new DiffRecord (filename);
 275         if (!get_bitmaps(drp, baseDir, comparisonDir)) {
 276             continue;
 277         }
 278
 279         const int w = drp->fBaseBitmap.width();
 280         const int h = drp->fBaseBitmap.height();
 281         drp->fDifferenceBitmap.setConfig(SkBitmap::kARGB_8888_Config, w, h);
 282         drp->fDifferenceBitmap.allocPixels();
 283         compute_diff(drp, dmp, colorThreshold);
 284
 285         SkString outPath (outputDir);
 286         outPath.append(filename);
 287         write_bitmap(outPath, drp->fDifferenceBitmap);
 288
 289         differences->push(drp);
 290         if (0 == drp->fMetricValue) {
 291             matchCount++;
 292         }
 293     }
 294
 295     SkQSort(differences->begin(), differences->count(), sizeof(DiffRecord*),
 296             scp);
 297     return matchCount;
 298 }
 299
 300 /// Make layout more consistent by scaling image to 240 height, 360 width,
 301 /// or natural size, whichever is smallest.
 302 static int compute_image_height (const SkBitmap& bmp) {
 303     int retval = 240;
 304     if (bmp.height() < retval) {
 305         retval = bmp.height();
 306     }
 307     float scale = (float) retval / bmp.height();
 308     if (bmp.width() * scale > 360) {
 309         scale = (float) 360 / bmp.width();
 310         retval = bmp.height() * scale;
 311     }
 312     return retval;
 313 }
 314
 315 static void print_page_header (SkFILEWStream* stream,
 316                                const int matchCount,
 317                                const int colorThreshold,
 318                                const RecordArray& differences) {
 319     SkTime::DateTime dt;
 320     SkTime::GetDateTime(&dt);
 321     stream->writeText("SkDiff run at ");
 322     stream->writeDecAsText(dt.fHour);
 323     stream->writeText(":");
 324     if (dt.fMinute < 10) {
 325         stream->writeText("0");
 326     }
 327     stream->writeDecAsText(dt.fMinute);
 328     stream->writeText(":");
 329     if (dt.fSecond < 10) {
 330         stream->writeText("0");
 331     }
 332     stream->writeDecAsText(dt.fSecond);
 333     stream->writeText("<br>");
 334     stream->writeDecAsText(matchCount);
 335     stream->writeText(" of ");
 336     stream->writeDecAsText(differences.count());
 337     stream->writeText(" images matched ");
 338     if (colorThreshold == 0) {
 339         stream->writeText("exactly");
 340     } else {
 341         stream->writeText("within ");
 342         stream->writeDecAsText(colorThreshold);
 343         stream->writeText(" color units per component");
 344     }
 345     stream->writeText(".<br>");
 346
 347 }
 348
 349 static void print_pixel_count (SkFILEWStream* stream,
 350                                const DiffRecord& diff) {
 351     stream->writeText("<br>(");
 352     stream->writeDecAsText(diff.fMetricValue *
 353                            diff.fBaseBitmap.width() *
 354                            diff.fBaseBitmap.height());
 355     stream->writeText(" pixels)");
 356 }
 357
 358 static void print_label_cell (SkFILEWStream* stream,
 359                               const DiffRecord& diff) {
 360     stream->writeText("<td>");
 361     stream->writeText(diff.fFilename.c_str());
 362     stream->writeText("<br>");
 363     char metricBuf [20];
 364     sprintf(metricBuf, "%12.4f%%", 100 * diff.fMetricValue);
 365     stream->writeText(metricBuf);
 366     stream->writeText(" of pixels differ");
 367     // Write the actual number of pixels that differ if it's < 1%
 368     if (diff.fMetricValue < 0.01) {
 369         print_pixel_count(stream, diff);
 370     }
 371     stream->writeText("<br>Average color mismatch ");
 372     stream->writeDecAsText(MAX3(diff.fAverageMismatchR,
 373                                 diff.fAverageMismatchG,
 374                                 diff.fAverageMismatchB));
 375     stream->writeText("<br>Max color mismatch ");
 376     stream->writeDecAsText(MAX3(diff.fMaxMismatchR,
 377                                 diff.fMaxMismatchG,
 378                                 diff.fMaxMismatchB));
 379     stream->writeText("</td>");
 380 }
 381
 382 static void print_image_cell (SkFILEWStream* stream,
 383                               const SkString& directory,
 384                               const SkString& filename,
 385                               int height) {
 386     stream->writeText("<td><a href=\"");
 387     stream->writeText(directory.c_str());
 388     stream->writeText(filename.c_str());
 389     stream->writeText("\"><img src=\"");
 390     stream->writeText(directory.c_str());
 391     stream->writeText(filename.c_str());
 392     stream->writeText("\" height=\"");
 393     stream->writeDecAsText(height);
 394     stream->writeText("px\"></a></td>");
 395 }
 396
 397 static void print_diff_page (const int matchCount,
 398                              const int colorThreshold,
 399                              const RecordArray& differences,
 400                              const SkString& baseDir,
 401                              const SkString& comparisonDir,
 402                              const SkString& outputDir) {
 403
 404     SkFILEWStream outputStream ("index.html");
 405
 406     outputStream.writeText("<html>\n<body>\n");
 407     print_page_header(&outputStream, matchCount, colorThreshold, differences);
 408
 409     outputStream.writeText("<table>\n");
 410     int i;
 411     for (i = 0; i < differences.count(); i++) {
 412         DiffRecord* diff = differences[i];
 413         if (0 == diff->fMetricValue) {
 414             continue;
 415         }
 416         int height = compute_image_height(diff->fBaseBitmap);
 417         outputStream.writeText("<tr>\n");
 418         print_label_cell(&outputStream, *diff);
 419         print_image_cell(&outputStream, baseDir, diff->fFilename, height);
 420         print_image_cell(&outputStream, outputDir, diff->fFilename, height);
 421         print_image_cell(&outputStream, comparisonDir, diff->fFilename,
 422                          height);
 423         outputStream.writeText("</tr>\n");
 424         outputStream.flush();
 425     }
 426     outputStream.writeText("</table>\n");
 427     outputStream.writeText("</body>\n</html>\n");
 428     outputStream.flush();
 429 }
 430
 431 static void usage (char * argv0) {
 432     SkDebugf("Skia baseline image diff tool\n");
 433     SkDebugf("Usage: %s baseDir comparisonDir outputDir\n", argv0);
 434     SkDebugf(
 435 "    -white: force all difference pixels to white\n"
 436 "    -threshold n: only report differences > n (in one channel) [default 0]\n"
 437 "    -sortbymismatch: sort by average color channel mismatch\n");
 438     SkDebugf(
 439 "    -sortbymaxmismatch: sort by worst color channel mismatch,\n"
 440 "                        break ties with -sortbymismatch,\n"
 441 "        [default by fraction of pixels mismatching]\n");
 442     SkDebugf("    baseDir: directory to read baseline images from\n");
 443     SkDebugf("    comparisonDir: directory to read comparison images from\n");
 444     SkDebugf("    outputDir: directory to write difference images to\n");
 445     SkDebugf("Also creates an \"index.html\" file in the current directory.\n");
 446 }
 447
 448 int main (int argc, char ** argv) {
 449     DiffMetricProc diffProc = compute_diff_pmcolor;
 450     SkQSortCompareProc sortProc = (SkQSortCompareProc) compare_diff_metrics;
 451
 452     // Maximum error tolerated in any one color channel in any one pixel before
 453     // a difference is reported.
 454     int colorThreshold = 0;
 455     SkString baseDir;
 456     SkString comparisonDir;
 457     SkString outputDir;
 458
 459     RecordArray differences;
 460
 461     int i, j;
 462     for (i = 1, j = 0; i < argc; i++) {
 463         if (!strcmp(argv[i], "-help")) {
 464             usage(argv[0]);
 465             return 0;
 466         }
 467         if (!strcmp(argv[i], "-white")) {
 468             diffProc = compute_diff_white;
 469             continue;
 470         }
 471         if (!strcmp(argv[i], "-sortbymismatch")) {
 472             sortProc = (SkQSortCompareProc) compare_diff_mean_mismatches;
 473             continue;
 474         }
 475         if (!strcmp(argv[i], "-sortbymaxmismatch")) {
 476             sortProc = (SkQSortCompareProc) compare_diff_max_mismatches;
 477             continue;
 478         }
 479         if (!strcmp(argv[i], "-threshold")) {
 480             colorThreshold = atoi(argv[++i]);
 481             continue;
 482         }
 483         if (argv[i][0] != '-') {
 484             switch (j++) {
 485                 case 0:
 486                     baseDir.set(argv[i]);
 487                     continue;
 488                 case 1:
 489                     comparisonDir.set(argv[i]);
 490                     continue;
 491                 case 2:
 492                     outputDir.set(argv[i]);
 493                     continue;
 494                 default:
 495                     usage(argv[0]);
 496                     return 0;
 497             }
 498         }
 499
 500         SkDebugf("Unrecognized argument <%s>\n", argv[i]);
 501         usage(argv[0]);
 502         return 0;
 503     }
 504     if (j != 3) {
 505       usage(argv[0]);
 506       return 0;
 507     }
 508
 509     if (!baseDir.endsWith("/")) {
 510         baseDir.append("/");
 511     }
 512     if (!comparisonDir.endsWith("/")) {
 513         comparisonDir.append("/");
 514     }
 515     if (!outputDir.endsWith("/")) {
 516         outputDir.append("/");
 517     }
 518
 519     int matchCount = create_diff_images(diffProc, sortProc,
 520                                         colorThreshold, &differences,
 521                                         baseDir, comparisonDir,
 522                                         outputDir);
 523     print_diff_page(matchCount, colorThreshold, differences,
 524                     baseDir, comparisonDir, outputDir);
 525
 526     for (i = 0; i < differences.count(); i++) {
 527         delete differences[i];
 528     }
 529 }