qemu/ui/vnc-enc-tight.c

   1 /*
   2  * QEMU VNC display driver: tight encoding
   3  *
   4  * From libvncserver/libvncserver/tight.c
   5  * Copyright (C) 2000, 2001 Const Kaplinsky.  All Rights Reserved.
   6  * Copyright (C) 1999 AT&T Laboratories Cambridge.  All Rights Reserved.
   7  *
   8  * Copyright (C) 2010 Corentin Chary <corentin.chary@gmail.com>
   9  *
  10  * Permission is hereby granted, free of charge, to any person obtaining a copy
  11  * of this software and associated documentation files (the "Software"), to deal
  12  * in the Software without restriction, including without limitation the rights
  13  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  14  * copies of the Software, and to permit persons to whom the Software is
  15  * furnished to do so, subject to the following conditions:
  16  *
  17  * The above copyright notice and this permission notice shall be included in
  18  * all copies or substantial portions of the Software.
  19  *
  20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  23  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  24  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  25  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  26  * THE SOFTWARE.
  27  */
  28
  29 #include "qemu/osdep.h"
  30
  31 /* This needs to be before jpeglib.h line because of conflict with
  32    INT32 definitions between jmorecfg.h (included by jpeglib.h) and
  33    Win32 basetsd.h (included by windows.h). */
  34 #include "qemu-common.h"
  35
  36 #ifdef CONFIG_VNC_PNG
  37 /* The following define is needed by pngconf.h. Otherwise it won't compile,
  38    because setjmp.h was already included by qemu-common.h. */
  39 #define PNG_SKIP_SETJMP_CHECK
  40 #include <png.h>
  41 #endif
  42 #ifdef CONFIG_VNC_JPEG
  43 #include <jpeglib.h>
  44 #endif
  45
  46 #include "qemu/bswap.h"
  47 #include "qapi/qmp/qint.h"
  48 #include "vnc.h"
  49 #include "vnc-enc-tight.h"
  50 #include "vnc-palette.h"
  51
  52 /* Compression level stuff. The following array contains various
  53    encoder parameters for each of 10 compression levels (0..9).
  54    Last three parameters correspond to JPEG quality levels (0..9). */
  55
  56 static const struct {
  57     int max_rect_size, max_rect_width;
  58     int mono_min_rect_size, gradient_min_rect_size;
  59     int idx_zlib_level, mono_zlib_level, raw_zlib_level, gradient_zlib_level;
  60     int gradient_threshold, gradient_threshold24;
  61     int idx_max_colors_divisor;
  62     int jpeg_quality, jpeg_threshold, jpeg_threshold24;
  63 } tight_conf[] = {
  64     {   512,   32,   6, 65536, 0, 0, 0, 0,   0,   0,   4,  5, 10000, 23000 },
  65     {  2048,  128,   6, 65536, 1, 1, 1, 0,   0,   0,   8, 10,  8000, 18000 },
  66     {  6144,  256,   8, 65536, 3, 3, 2, 0,   0,   0,  24, 15,  6500, 15000 },
  67     { 10240, 1024,  12, 65536, 5, 5, 3, 0,   0,   0,  32, 25,  5000, 12000 },
  68     { 16384, 2048,  12, 65536, 6, 6, 4, 0,   0,   0,  32, 37,  4000, 10000 },
  69     { 32768, 2048,  12,  4096, 7, 7, 5, 4, 150, 380,  32, 50,  3000,  8000 },
  70     { 65536, 2048,  16,  4096, 7, 7, 6, 4, 170, 420,  48, 60,  2000,  5000 },
  71     { 65536, 2048,  16,  4096, 8, 8, 7, 5, 180, 450,  64, 70,  1000,  2500 },
  72     { 65536, 2048,  32,  8192, 9, 9, 8, 6, 190, 475,  64, 75,   500,  1200 },
  73     { 65536, 2048,  32,  8192, 9, 9, 9, 6, 200, 500,  96, 80,   200,   500 }
  74 };
  75
  76
  77 static int tight_send_framebuffer_update(VncState *vs, int x, int y,
  78                                          int w, int h);
  79
  80 #ifdef CONFIG_VNC_JPEG
  81 static const struct {
  82     double jpeg_freq_min;       /* Don't send JPEG if the freq is bellow */
  83     double jpeg_freq_threshold; /* Always send JPEG if the freq is above */
  84     int jpeg_idx;               /* Allow indexed JPEG */
  85     int jpeg_full;              /* Allow full color JPEG */
  86 } tight_jpeg_conf[] = {
  87     { 0,   8,  1, 1 },
  88     { 0,   8,  1, 1 },
  89     { 0,   8,  1, 1 },
  90     { 0,   8,  1, 1 },
  91     { 0,   10, 1, 1 },
  92     { 0.1, 10, 1, 1 },
  93     { 0.2, 10, 1, 1 },
  94     { 0.3, 12, 0, 0 },
  95     { 0.4, 14, 0, 0 },
  96     { 0.5, 16, 0, 0 },
  97 };
  98 #endif
  99
 100 #ifdef CONFIG_VNC_PNG
 101 static const struct {
 102     int png_zlib_level, png_filters;
 103 } tight_png_conf[] = {
 104     { 0, PNG_NO_FILTERS },
 105     { 1, PNG_NO_FILTERS },
 106     { 2, PNG_NO_FILTERS },
 107     { 3, PNG_NO_FILTERS },
 108     { 4, PNG_NO_FILTERS },
 109     { 5, PNG_ALL_FILTERS },
 110     { 6, PNG_ALL_FILTERS },
 111     { 7, PNG_ALL_FILTERS },
 112     { 8, PNG_ALL_FILTERS },
 113     { 9, PNG_ALL_FILTERS },
 114 };
 115
 116 static int send_png_rect(VncState *vs, int x, int y, int w, int h,
 117                          VncPalette *palette);
 118
 119 static bool tight_can_send_png_rect(VncState *vs, int w, int h)
 120 {
 121     if (vs->tight.type != VNC_ENCODING_TIGHT_PNG) {
 122         return false;
 123     }
 124
 125     if (surface_bytes_per_pixel(vs->vd->ds) == 1 ||
 126         vs->client_pf.bytes_per_pixel == 1) {
 127         return false;
 128     }
 129
 130     return true;
 131 }
 132 #endif
 133
 134 /*
 135  * Code to guess if given rectangle is suitable for smooth image
 136  * compression (by applying "gradient" filter or JPEG coder).
 137  */
 138
 139 static unsigned int
 140 tight_detect_smooth_image24(VncState *vs, int w, int h)
 141 {
 142     int off;
 143     int x, y, d, dx;
 144     unsigned int c;
 145     unsigned int stats[256];
 146     int pixels = 0;
 147     int pix, left[3];
 148     unsigned int errors;
 149     unsigned char *buf = vs->tight.tight.buffer;
 150
 151     /*
 152      * If client is big-endian, color samples begin from the second
 153      * byte (offset 1) of a 32-bit pixel value.
 154      */
 155     off = vs->client_be;
 156
 157     memset(stats, 0, sizeof (stats));
 158
 159     for (y = 0, x = 0; y < h && x < w;) {
 160         for (d = 0; d < h - y && d < w - x - VNC_TIGHT_DETECT_SUBROW_WIDTH;
 161              d++) {
 162             for (c = 0; c < 3; c++) {
 163                 left[c] = buf[((y+d)*w+x+d)*4+off+c] & 0xFF;
 164             }
 165             for (dx = 1; dx <= VNC_TIGHT_DETECT_SUBROW_WIDTH; dx++) {
 166                 for (c = 0; c < 3; c++) {
 167                     pix = buf[((y+d)*w+x+d+dx)*4+off+c] & 0xFF;
 168                     stats[abs(pix - left[c])]++;
 169                     left[c] = pix;
 170                 }
 171                 pixels++;
 172             }
 173         }
 174         if (w > h) {
 175             x += h;
 176             y = 0;
 177         } else {
 178             x = 0;
 179             y += w;
 180         }
 181     }
 182
 183     if (pixels == 0) {
 184         return 0;
 185     }
 186
 187     /* 95% smooth or more ... */
 188     if (stats[0] * 33 / pixels >= 95) {
 189         return 0;
 190     }
 191
 192     errors = 0;
 193     for (c = 1; c < 8; c++) {
 194         errors += stats[c] * (c * c);
 195         if (stats[c] == 0 || stats[c] > stats[c-1] * 2) {
 196             return 0;
 197         }
 198     }
 199     for (; c < 256; c++) {
 200         errors += stats[c] * (c * c);
 201     }
 202     errors /= (pixels * 3 - stats[0]);
 203
 204     return errors;
 205 }
 206
 207 #define DEFINE_DETECT_FUNCTION(bpp)                                     \
 208                                                                         \
 209     static unsigned int                                                 \
 210     tight_detect_smooth_image##bpp(VncState *vs, int w, int h) {        \
 211         bool endian;                                                    \
 212         uint##bpp##_t pix;                                              \
 213         int max[3], shift[3];                                           \
 214         int x, y, d, dx;                                                \
 215         unsigned int c;                                                 \
 216         unsigned int stats[256];                                        \
 217         int pixels = 0;                                                 \
 218         int sample, sum, left[3];                                       \
 219         unsigned int errors;                                            \
 220         unsigned char *buf = vs->tight.tight.buffer;                    \
 221                                                                         \
 222         endian = 0; /* FIXME */                                         \
 223                                                                         \
 224                                                                         \
 225         max[0] = vs->client_pf.rmax;                                  \
 226         max[1] = vs->client_pf.gmax;                                  \
 227         max[2] = vs->client_pf.bmax;                                  \
 228         shift[0] = vs->client_pf.rshift;                              \
 229         shift[1] = vs->client_pf.gshift;                              \
 230         shift[2] = vs->client_pf.bshift;                              \
 231                                                                         \
 232         memset(stats, 0, sizeof(stats));                                \
 233                                                                         \
 234         y = 0, x = 0;                                                   \
 235         while (y < h && x < w) {                                        \
 236             for (d = 0; d < h - y &&                                    \
 237                      d < w - x - VNC_TIGHT_DETECT_SUBROW_WIDTH; d++) {  \
 238                 pix = ((uint##bpp##_t *)buf)[(y+d)*w+x+d];              \
 239                 if (endian) {                                           \
 240                     pix = bswap##bpp(pix);                              \
 241                 }                                                       \
 242                 for (c = 0; c < 3; c++) {                               \
 243                     left[c] = (int)(pix >> shift[c] & max[c]);          \
 244                 }                                                       \
 245                 for (dx = 1; dx <= VNC_TIGHT_DETECT_SUBROW_WIDTH;       \
 246                      dx++) {                                            \
 247                     pix = ((uint##bpp##_t *)buf)[(y+d)*w+x+d+dx];       \
 248                     if (endian) {                                       \
 249                         pix = bswap##bpp(pix);                          \
 250                     }                                                   \
 251                     sum = 0;                                            \
 252                     for (c = 0; c < 3; c++) {                           \
 253                         sample = (int)(pix >> shift[c] & max[c]);       \
 254                         sum += abs(sample - left[c]);                   \
 255                         left[c] = sample;                               \
 256                     }                                                   \
 257                     if (sum > 255) {                                    \
 258                         sum = 255;                                      \
 259                     }                                                   \
 260                     stats[sum]++;                                       \
 261                     pixels++;                                           \
 262                 }                                                       \
 263             }                                                           \
 264             if (w > h) {                                                \
 265                 x += h;                                                 \
 266                 y = 0;                                                  \
 267             } else {                                                    \
 268                 x = 0;                                                  \
 269                 y += w;                                                 \
 270             }                                                           \
 271         }                                                               \
 272         if (pixels == 0) {                                              \
 273             return 0;                                                   \
 274         }                                                               \
 275         if ((stats[0] + stats[1]) * 100 / pixels >= 90) {               \
 276             return 0;                                                   \
 277         }                                                               \
 278                                                                         \
 279         errors = 0;                                                     \
 280         for (c = 1; c < 8; c++) {                                       \
 281             errors += stats[c] * (c * c);                               \
 282             if (stats[c] == 0 || stats[c] > stats[c-1] * 2) {           \
 283                 return 0;                                               \
 284             }                                                           \
 285         }                                                               \
 286         for (; c < 256; c++) {                                          \
 287             errors += stats[c] * (c * c);                               \
 288         }                                                               \
 289         errors /= (pixels - stats[0]);                                  \
 290                                                                         \
 291         return errors;                                                  \
 292     }
 293
 294 DEFINE_DETECT_FUNCTION(16)
 295 DEFINE_DETECT_FUNCTION(32)
 296
 297 static int
 298 tight_detect_smooth_image(VncState *vs, int w, int h)
 299 {
 300     unsigned int errors;
 301     int compression = vs->tight.compression;
 302     int quality = vs->tight.quality;
 303
 304     if (!vs->vd->lossy) {
 305         return 0;
 306     }
 307
 308     if (surface_bytes_per_pixel(vs->vd->ds) == 1 ||
 309         vs->client_pf.bytes_per_pixel == 1 ||
 310         w < VNC_TIGHT_DETECT_MIN_WIDTH || h < VNC_TIGHT_DETECT_MIN_HEIGHT) {
 311         return 0;
 312     }
 313
 314     if (vs->tight.quality != (uint8_t)-1) {
 315         if (w * h < VNC_TIGHT_JPEG_MIN_RECT_SIZE) {
 316             return 0;
 317         }
 318     } else {
 319         if (w * h < tight_conf[compression].gradient_min_rect_size) {
 320             return 0;
 321         }
 322     }
 323
 324     if (vs->client_pf.bytes_per_pixel == 4) {
 325         if (vs->tight.pixel24) {
 326             errors = tight_detect_smooth_image24(vs, w, h);
 327             if (vs->tight.quality != (uint8_t)-1) {
 328                 return (errors < tight_conf[quality].jpeg_threshold24);
 329             }
 330             return (errors < tight_conf[compression].gradient_threshold24);
 331         } else {
 332             errors = tight_detect_smooth_image32(vs, w, h);
 333         }
 334     } else {
 335         errors = tight_detect_smooth_image16(vs, w, h);
 336     }
 337     if (quality != (uint8_t)-1) {
 338         return (errors < tight_conf[quality].jpeg_threshold);
 339     }
 340     return (errors < tight_conf[compression].gradient_threshold);
 341 }
 342
 343 /*
 344  * Code to determine how many different colors used in rectangle.
 345  */
 346 #define DEFINE_FILL_PALETTE_FUNCTION(bpp)                               \
 347                                                                         \
 348     static int                                                          \
 349     tight_fill_palette##bpp(VncState *vs, int x, int y,                 \
 350                             int max, size_t count,                      \
 351                             uint32_t *bg, uint32_t *fg,                 \
 352                             VncPalette **palette) {                     \
 353         uint##bpp##_t *data;                                            \
 354         uint##bpp##_t c0, c1, ci;                                       \
 355         int i, n0, n1;                                                  \
 356                                                                         \
 357         data = (uint##bpp##_t *)vs->tight.tight.buffer;                 \
 358                                                                         \
 359         c0 = data[0];                                                   \
 360         i = 1;                                                          \
 361         while (i < count && data[i] == c0)                              \
 362             i++;                                                        \
 363         if (i >= count) {                                               \
 364             *bg = *fg = c0;                                             \
 365             return 1;                                                   \
 366         }                                                               \
 367                                                                         \
 368         if (max < 2) {                                                  \
 369             return 0;                                                   \
 370         }                                                               \
 371                                                                         \
 372         n0 = i;                                                         \
 373         c1 = data[i];                                                   \
 374         n1 = 0;                                                         \
 375         for (i++; i < count; i++) {                                     \
 376             ci = data[i];                                               \
 377             if (ci == c0) {                                             \
 378                 n0++;                                                   \
 379             } else if (ci == c1) {                                      \
 380                 n1++;                                                   \
 381             } else                                                      \
 382                 break;                                                  \
 383         }                                                               \
 384         if (i >= count) {                                               \
 385             if (n0 > n1) {                                              \
 386                 *bg = (uint32_t)c0;                                     \
 387                 *fg = (uint32_t)c1;                                     \
 388             } else {                                                    \
 389                 *bg = (uint32_t)c1;                                     \
 390                 *fg = (uint32_t)c0;                                     \
 391             }                                                           \
 392             return 2;                                                   \
 393         }                                                               \
 394                                                                         \
 395         if (max == 2) {                                                 \
 396             return 0;                                                   \
 397         }                                                               \
 398                                                                         \
 399         *palette = palette_new(max, bpp);                               \
 400         palette_put(*palette, c0);                                      \
 401         palette_put(*palette, c1);                                      \
 402         palette_put(*palette, ci);                                      \
 403                                                                         \
 404         for (i++; i < count; i++) {                                     \
 405             if (data[i] == ci) {                                        \
 406                 continue;                                               \
 407             } else {                                                    \
 408                 ci = data[i];                                           \
 409                 if (!palette_put(*palette, (uint32_t)ci)) {             \
 410                     return 0;                                           \
 411                 }                                                       \
 412             }                                                           \
 413         }                                                               \
 414                                                                         \
 415         return palette_size(*palette);                                  \
 416     }
 417
 418 DEFINE_FILL_PALETTE_FUNCTION(8)
 419 DEFINE_FILL_PALETTE_FUNCTION(16)
 420 DEFINE_FILL_PALETTE_FUNCTION(32)
 421
 422 static int tight_fill_palette(VncState *vs, int x, int y,
 423                               size_t count, uint32_t *bg, uint32_t *fg,
 424                               VncPalette **palette)
 425 {
 426     int max;
 427
 428     max = count / tight_conf[vs->tight.compression].idx_max_colors_divisor;
 429     if (max < 2 &&
 430         count >= tight_conf[vs->tight.compression].mono_min_rect_size) {
 431         max = 2;
 432     }
 433     if (max >= 256) {
 434         max = 256;
 435     }
 436
 437     switch (vs->client_pf.bytes_per_pixel) {
 438     case 4:
 439         return tight_fill_palette32(vs, x, y, max, count, bg, fg, palette);
 440     case 2:
 441         return tight_fill_palette16(vs, x, y, max, count, bg, fg, palette);
 442     default:
 443         max = 2;
 444         return tight_fill_palette8(vs, x, y, max, count, bg, fg, palette);
 445     }
 446     return 0;
 447 }
 448
 449 /*
 450  * Converting truecolor samples into palette indices.
 451  */
 452 #define DEFINE_IDX_ENCODE_FUNCTION(bpp)                                 \
 453                                                                         \
 454     static void                                                         \
 455     tight_encode_indexed_rect##bpp(uint8_t *buf, int count,             \
 456                                    VncPalette *palette) {               \
 457         uint##bpp##_t *src;                                             \
 458         uint##bpp##_t rgb;                                              \
 459         int i, rep;                                                     \
 460         uint8_t idx;                                                    \
 461                                                                         \
 462         src = (uint##bpp##_t *) buf;                                    \
 463                                                                         \
 464         for (i = 0; i < count; i++) {                                   \
 465                                                                         \
 466             rgb = *src++;                                               \
 467             rep = 0;                                                    \
 468             while (i < count && *src == rgb) {                          \
 469                 rep++, src++, i++;                                      \
 470             }                                                           \
 471             idx = palette_idx(palette, rgb);                            \
 472             /*                                                          \
 473              * Should never happen, but don't break everything          \
 474              * if it does, use the first color instead                  \
 475              */                                                         \
 476             if (idx == (uint8_t)-1) {                                   \
 477                 idx = 0;                                                \
 478             }                                                           \
 479             while (rep >= 0) {                                          \
 480                 *buf++ = idx;                                           \
 481                 rep--;                                                  \
 482             }                                                           \
 483         }                                                               \
 484     }
 485
 486 DEFINE_IDX_ENCODE_FUNCTION(16)
 487 DEFINE_IDX_ENCODE_FUNCTION(32)
 488
 489 #define DEFINE_MONO_ENCODE_FUNCTION(bpp)                                \
 490                                                                         \
 491     static void                                                         \
 492     tight_encode_mono_rect##bpp(uint8_t *buf, int w, int h,             \
 493                                 uint##bpp##_t bg, uint##bpp##_t fg) {   \
 494         uint##bpp##_t *ptr;                                             \
 495         unsigned int value, mask;                                       \
 496         int aligned_width;                                              \
 497         int x, y, bg_bits;                                              \
 498                                                                         \
 499         ptr = (uint##bpp##_t *) buf;                                    \
 500         aligned_width = w - w % 8;                                      \
 501                                                                         \
 502         for (y = 0; y < h; y++) {                                       \
 503             for (x = 0; x < aligned_width; x += 8) {                    \
 504                 for (bg_bits = 0; bg_bits < 8; bg_bits++) {             \
 505                     if (*ptr++ != bg) {                                 \
 506                         break;                                          \
 507                     }                                                   \
 508                 }                                                       \
 509                 if (bg_bits == 8) {                                     \
 510                     *buf++ = 0;                                         \
 511                     continue;                                           \
 512                 }                                                       \
 513                 mask = 0x80 >> bg_bits;                                 \
 514                 value = mask;                                           \
 515                 for (bg_bits++; bg_bits < 8; bg_bits++) {               \
 516                     mask >>= 1;                                         \
 517                     if (*ptr++ != bg) {                                 \
 518                         value |= mask;                                  \
 519                     }                                                   \
 520                 }                                                       \
 521                 *buf++ = (uint8_t)value;                                \
 522             }                                                           \
 523                                                                         \
 524             mask = 0x80;                                                \
 525             value = 0;                                                  \
 526             if (x >= w) {                                               \
 527                 continue;                                               \
 528             }                                                           \
 529                                                                         \
 530             for (; x < w; x++) {                                        \
 531                 if (*ptr++ != bg) {                                     \
 532                     value |= mask;                                      \
 533                 }                                                       \
 534                 mask >>= 1;                                             \
 535             }                                                           \
 536             *buf++ = (uint8_t)value;                                    \
 537         }                                                               \
 538     }
 539
 540 DEFINE_MONO_ENCODE_FUNCTION(8)
 541 DEFINE_MONO_ENCODE_FUNCTION(16)
 542 DEFINE_MONO_ENCODE_FUNCTION(32)
 543
 544 /*
 545  * ``Gradient'' filter for 24-bit color samples.
 546  * Should be called only when redMax, greenMax and blueMax are 255.
 547  * Color components assumed to be byte-aligned.
 548  */
 549
 550 static void
 551 tight_filter_gradient24(VncState *vs, uint8_t *buf, int w, int h)
 552 {
 553     uint32_t *buf32;
 554     uint32_t pix32;
 555     int shift[3];
 556     int *prev;
 557     int here[3], upper[3], left[3], upperleft[3];
 558     int prediction;
 559     int x, y, c;
 560
 561     buf32 = (uint32_t *)buf;
 562     memset(vs->tight.gradient.buffer, 0, w * 3 * sizeof(int));
 563
 564     if (1 /* FIXME */) {
 565         shift[0] = vs->client_pf.rshift;
 566         shift[1] = vs->client_pf.gshift;
 567         shift[2] = vs->client_pf.bshift;
 568     } else {
 569         shift[0] = 24 - vs->client_pf.rshift;
 570         shift[1] = 24 - vs->client_pf.gshift;
 571         shift[2] = 24 - vs->client_pf.bshift;
 572     }
 573
 574     for (y = 0; y < h; y++) {
 575         for (c = 0; c < 3; c++) {
 576             upper[c] = 0;
 577             here[c] = 0;
 578         }
 579         prev = (int *)vs->tight.gradient.buffer;
 580         for (x = 0; x < w; x++) {
 581             pix32 = *buf32++;
 582             for (c = 0; c < 3; c++) {
 583                 upperleft[c] = upper[c];
 584                 left[c] = here[c];
 585                 upper[c] = *prev;
 586                 here[c] = (int)(pix32 >> shift[c] & 0xFF);
 587                 *prev++ = here[c];
 588
 589                 prediction = left[c] + upper[c] - upperleft[c];
 590                 if (prediction < 0) {
 591                     prediction = 0;
 592                 } else if (prediction > 0xFF) {
 593                     prediction = 0xFF;
 594                 }
 595                 *buf++ = (char)(here[c] - prediction);
 596             }
 597         }
 598     }
 599 }
 600
 601
 602 /*
 603  * ``Gradient'' filter for other color depths.
 604  */
 605
 606 #define DEFINE_GRADIENT_FILTER_FUNCTION(bpp)                            \
 607                                                                         \
 608     static void                                                         \
 609     tight_filter_gradient##bpp(VncState *vs, uint##bpp##_t *buf,        \
 610                                int w, int h) {                          \
 611         uint##bpp##_t pix, diff;                                        \
 612         bool endian;                                                    \
 613         int *prev;                                                      \
 614         int max[3], shift[3];                                           \
 615         int here[3], upper[3], left[3], upperleft[3];                   \
 616         int prediction;                                                 \
 617         int x, y, c;                                                    \
 618                                                                         \
 619         memset (vs->tight.gradient.buffer, 0, w * 3 * sizeof(int));     \
 620                                                                         \
 621         endian = 0; /* FIXME */                                         \
 622                                                                         \
 623         max[0] = vs->client_pf.rmax;                                    \
 624         max[1] = vs->client_pf.gmax;                                    \
 625         max[2] = vs->client_pf.bmax;                                    \
 626         shift[0] = vs->client_pf.rshift;                                \
 627         shift[1] = vs->client_pf.gshift;                                \
 628         shift[2] = vs->client_pf.bshift;                                \
 629                                                                         \
 630         for (y = 0; y < h; y++) {                                       \
 631             for (c = 0; c < 3; c++) {                                   \
 632                 upper[c] = 0;                                           \
 633                 here[c] = 0;                                            \
 634             }                                                           \
 635             prev = (int *)vs->tight.gradient.buffer;                    \
 636             for (x = 0; x < w; x++) {                                   \
 637                 pix = *buf;                                             \
 638                 if (endian) {                                           \
 639                     pix = bswap##bpp(pix);                              \
 640                 }                                                       \
 641                 diff = 0;                                               \
 642                 for (c = 0; c < 3; c++) {                               \
 643                     upperleft[c] = upper[c];                            \
 644                     left[c] = here[c];                                  \
 645                     upper[c] = *prev;                                   \
 646                     here[c] = (int)(pix >> shift[c] & max[c]);          \
 647                     *prev++ = here[c];                                  \
 648                                                                         \
 649                     prediction = left[c] + upper[c] - upperleft[c];     \
 650                     if (prediction < 0) {                               \
 651                         prediction = 0;                                 \
 652                     } else if (prediction > max[c]) {                   \
 653                         prediction = max[c];                            \
 654                     }                                                   \
 655                     diff |= ((here[c] - prediction) & max[c])           \
 656                         << shift[c];                                    \
 657                 }                                                       \
 658                 if (endian) {                                           \
 659                     diff = bswap##bpp(diff);                            \
 660                 }                                                       \
 661                 *buf++ = diff;                                          \
 662             }                                                           \
 663         }                                                               \
 664     }
 665
 666 DEFINE_GRADIENT_FILTER_FUNCTION(16)
 667 DEFINE_GRADIENT_FILTER_FUNCTION(32)
 668
 669 /*
 670  * Check if a rectangle is all of the same color. If needSameColor is
 671  * set to non-zero, then also check that its color equals to the
 672  * *colorPtr value. The result is 1 if the test is successful, and in
 673  * that case new color will be stored in *colorPtr.
 674  */
 675
 676 static bool
 677 check_solid_tile32(VncState *vs, int x, int y, int w, int h,
 678                    uint32_t *color, bool samecolor)
 679 {
 680     VncDisplay *vd = vs->vd;
 681     uint32_t *fbptr;
 682     uint32_t c;
 683     int dx, dy;
 684
 685     fbptr = vnc_server_fb_ptr(vd, x, y);
 686
 687     c = *fbptr;
 688     if (samecolor && (uint32_t)c != *color) {
 689         return false;
 690     }
 691
 692     for (dy = 0; dy < h; dy++) {
 693         for (dx = 0; dx < w; dx++) {
 694             if (c != fbptr[dx]) {
 695                 return false;
 696             }
 697         }
 698         fbptr = (uint32_t *)
 699             ((uint8_t *)fbptr + vnc_server_fb_stride(vd));
 700     }
 701
 702     *color = (uint32_t)c;
 703     return true;
 704 }
 705
 706 static bool check_solid_tile(VncState *vs, int x, int y, int w, int h,
 707                              uint32_t* color, bool samecolor)
 708 {
 709     switch (VNC_SERVER_FB_BYTES) {
 710     case 4:
 711         return check_solid_tile32(vs, x, y, w, h, color, samecolor);
 712     }
 713 }
 714
 715 static void find_best_solid_area(VncState *vs, int x, int y, int w, int h,
 716                                  uint32_t color, int *w_ptr, int *h_ptr)
 717 {
 718     int dx, dy, dw, dh;
 719     int w_prev;
 720     int w_best = 0, h_best = 0;
 721
 722     w_prev = w;
 723
 724     for (dy = y; dy < y + h; dy += VNC_TIGHT_MAX_SPLIT_TILE_SIZE) {
 725
 726         dh = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, y + h - dy);
 727         dw = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, w_prev);
 728
 729         if (!check_solid_tile(vs, x, dy, dw, dh, &color, true)) {
 730             break;
 731         }
 732
 733         for (dx = x + dw; dx < x + w_prev;) {
 734             dw = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, x + w_prev - dx);
 735
 736             if (!check_solid_tile(vs, dx, dy, dw, dh, &color, true)) {
 737                 break;
 738             }
 739             dx += dw;
 740         }
 741
 742         w_prev = dx - x;
 743         if (w_prev * (dy + dh - y) > w_best * h_best) {
 744             w_best = w_prev;
 745             h_best = dy + dh - y;
 746         }
 747     }
 748
 749     *w_ptr = w_best;
 750     *h_ptr = h_best;
 751 }
 752
 753 static void extend_solid_area(VncState *vs, int x, int y, int w, int h,
 754                               uint32_t color, int *x_ptr, int *y_ptr,
 755                               int *w_ptr, int *h_ptr)
 756 {
 757     int cx, cy;
 758
 759     /* Try to extend the area upwards. */
 760     for ( cy = *y_ptr - 1;
 761           cy >= y && check_solid_tile(vs, *x_ptr, cy, *w_ptr, 1, &color, true);
 762           cy-- );
 763     *h_ptr += *y_ptr - (cy + 1);
 764     *y_ptr = cy + 1;
 765
 766     /* ... downwards. */
 767     for ( cy = *y_ptr + *h_ptr;
 768           cy < y + h &&
 769               check_solid_tile(vs, *x_ptr, cy, *w_ptr, 1, &color, true);
 770           cy++ );
 771     *h_ptr += cy - (*y_ptr + *h_ptr);
 772
 773     /* ... to the left. */
 774     for ( cx = *x_ptr - 1;
 775           cx >= x && check_solid_tile(vs, cx, *y_ptr, 1, *h_ptr, &color, true);
 776           cx-- );
 777     *w_ptr += *x_ptr - (cx + 1);
 778     *x_ptr = cx + 1;
 779
 780     /* ... to the right. */
 781     for ( cx = *x_ptr + *w_ptr;
 782           cx < x + w &&
 783               check_solid_tile(vs, cx, *y_ptr, 1, *h_ptr, &color, true);
 784           cx++ );
 785     *w_ptr += cx - (*x_ptr + *w_ptr);
 786 }
 787
 788 static int tight_init_stream(VncState *vs, int stream_id,
 789                              int level, int strategy)
 790 {
 791     z_streamp zstream = &vs->tight.stream[stream_id];
 792
 793     if (zstream->opaque == NULL) {
 794         int err;
 795
 796         VNC_DEBUG("VNC: TIGHT: initializing zlib stream %d\n", stream_id);
 797         VNC_DEBUG("VNC: TIGHT: opaque = %p | vs = %p\n", zstream->opaque, vs);
 798         zstream->zalloc = vnc_zlib_zalloc;
 799         zstream->zfree = vnc_zlib_zfree;
 800
 801         err = deflateInit2(zstream, level, Z_DEFLATED, MAX_WBITS,
 802                            MAX_MEM_LEVEL, strategy);
 803
 804         if (err != Z_OK) {
 805             fprintf(stderr, "VNC: error initializing zlib\n");
 806             return -1;
 807         }
 808
 809         vs->tight.levels[stream_id] = level;
 810         zstream->opaque = vs;
 811     }
 812
 813     if (vs->tight.levels[stream_id] != level) {
 814         if (deflateParams(zstream, level, strategy) != Z_OK) {
 815             return -1;
 816         }
 817         vs->tight.levels[stream_id] = level;
 818     }
 819     return 0;
 820 }
 821
 822 static void tight_send_compact_size(VncState *vs, size_t len)
 823 {
 824     int lpc = 0;
 825     int bytes = 0;
 826     char buf[3] = {0, 0, 0};
 827
 828     buf[bytes++] = len & 0x7F;
 829     if (len > 0x7F) {
 830         buf[bytes-1] |= 0x80;
 831         buf[bytes++] = (len >> 7) & 0x7F;
 832         if (len > 0x3FFF) {
 833             buf[bytes-1] |= 0x80;
 834             buf[bytes++] = (len >> 14) & 0xFF;
 835         }
 836     }
 837     for (lpc = 0; lpc < bytes; lpc++) {
 838         vnc_write_u8(vs, buf[lpc]);
 839     }
 840 }
 841
 842 static int tight_compress_data(VncState *vs, int stream_id, size_t bytes,
 843                                int level, int strategy)
 844 {
 845     z_streamp zstream = &vs->tight.stream[stream_id];
 846     int previous_out;
 847
 848     if (bytes < VNC_TIGHT_MIN_TO_COMPRESS) {
 849         vnc_write(vs, vs->tight.tight.buffer, vs->tight.tight.offset);
 850         return bytes;
 851     }
 852
 853     if (tight_init_stream(vs, stream_id, level, strategy)) {
 854         return -1;
 855     }
 856
 857     /* reserve memory in output buffer */
 858     buffer_reserve(&vs->tight.zlib, bytes + 64);
 859
 860     /* set pointers */
 861     zstream->next_in = vs->tight.tight.buffer;
 862     zstream->avail_in = vs->tight.tight.offset;
 863     zstream->next_out = vs->tight.zlib.buffer + vs->tight.zlib.offset;
 864     zstream->avail_out = vs->tight.zlib.capacity - vs->tight.zlib.offset;
 865     previous_out = zstream->avail_out;
 866     zstream->data_type = Z_BINARY;
 867
 868     /* start encoding */
 869     if (deflate(zstream, Z_SYNC_FLUSH) != Z_OK) {
 870         fprintf(stderr, "VNC: error during tight compression\n");
 871         return -1;
 872     }
 873
 874     vs->tight.zlib.offset = vs->tight.zlib.capacity - zstream->avail_out;
 875     /* ...how much data has actually been produced by deflate() */
 876     bytes = previous_out - zstream->avail_out;
 877
 878     tight_send_compact_size(vs, bytes);
 879     vnc_write(vs, vs->tight.zlib.buffer, bytes);
 880
 881     buffer_reset(&vs->tight.zlib);
 882
 883     return bytes;
 884 }
 885
 886 /*
 887  * Subencoding implementations.
 888  */
 889 static void tight_pack24(VncState *vs, uint8_t *buf, size_t count, size_t *ret)
 890 {
 891     uint32_t *buf32;
 892     uint32_t pix;
 893     int rshift, gshift, bshift;
 894
 895     buf32 = (uint32_t *)buf;
 896
 897     if (1 /* FIXME */) {
 898         rshift = vs->client_pf.rshift;
 899         gshift = vs->client_pf.gshift;
 900         bshift = vs->client_pf.bshift;
 901     } else {
 902         rshift = 24 - vs->client_pf.rshift;
 903         gshift = 24 - vs->client_pf.gshift;
 904         bshift = 24 - vs->client_pf.bshift;
 905     }
 906
 907     if (ret) {
 908         *ret = count * 3;
 909     }
 910
 911     while (count--) {
 912         pix = *buf32++;
 913         *buf++ = (char)(pix >> rshift);
 914         *buf++ = (char)(pix >> gshift);
 915         *buf++ = (char)(pix >> bshift);
 916     }
 917 }
 918
 919 static int send_full_color_rect(VncState *vs, int x, int y, int w, int h)
 920 {
 921     int stream = 0;
 922     ssize_t bytes;
 923
 924 #ifdef CONFIG_VNC_PNG
 925     if (tight_can_send_png_rect(vs, w, h)) {
 926         return send_png_rect(vs, x, y, w, h, NULL);
 927     }
 928 #endif
 929
 930     vnc_write_u8(vs, stream << 4); /* no flushing, no filter */
 931
 932     if (vs->tight.pixel24) {
 933         tight_pack24(vs, vs->tight.tight.buffer, w * h, &vs->tight.tight.offset);
 934         bytes = 3;
 935     } else {
 936         bytes = vs->client_pf.bytes_per_pixel;
 937     }
 938
 939     bytes = tight_compress_data(vs, stream, w * h * bytes,
 940                                 tight_conf[vs->tight.compression].raw_zlib_level,
 941                                 Z_DEFAULT_STRATEGY);
 942
 943     return (bytes >= 0);
 944 }
 945
 946 static int send_solid_rect(VncState *vs)
 947 {
 948     size_t bytes;
 949
 950     vnc_write_u8(vs, VNC_TIGHT_FILL << 4); /* no flushing, no filter */
 951
 952     if (vs->tight.pixel24) {
 953         tight_pack24(vs, vs->tight.tight.buffer, 1, &vs->tight.tight.offset);
 954         bytes = 3;
 955     } else {
 956         bytes = vs->client_pf.bytes_per_pixel;
 957     }
 958
 959     vnc_write(vs, vs->tight.tight.buffer, bytes);
 960     return 1;
 961 }
 962
 963 static int send_mono_rect(VncState *vs, int x, int y,
 964                           int w, int h, uint32_t bg, uint32_t fg)
 965 {
 966     ssize_t bytes;
 967     int stream = 1;
 968     int level = tight_conf[vs->tight.compression].mono_zlib_level;
 969
 970 #ifdef CONFIG_VNC_PNG
 971     if (tight_can_send_png_rect(vs, w, h)) {
 972         int ret;
 973         int bpp = vs->client_pf.bytes_per_pixel * 8;
 974         VncPalette *palette = palette_new(2, bpp);
 975
 976         palette_put(palette, bg);
 977         palette_put(palette, fg);
 978         ret = send_png_rect(vs, x, y, w, h, palette);
 979         palette_destroy(palette);
 980         return ret;
 981     }
 982 #endif
 983
 984     bytes = ((w + 7) / 8) * h;
 985
 986     vnc_write_u8(vs, (stream | VNC_TIGHT_EXPLICIT_FILTER) << 4);
 987     vnc_write_u8(vs, VNC_TIGHT_FILTER_PALETTE);
 988     vnc_write_u8(vs, 1);
 989
 990     switch (vs->client_pf.bytes_per_pixel) {
 991     case 4:
 992     {
 993         uint32_t buf[2] = {bg, fg};
 994         size_t ret = sizeof (buf);
 995
 996         if (vs->tight.pixel24) {
 997             tight_pack24(vs, (unsigned char*)buf, 2, &ret);
 998         }
 999         vnc_write(vs, buf, ret);
1000
1001         tight_encode_mono_rect32(vs->tight.tight.buffer, w, h, bg, fg);
1002         break;
1003     }
1004     case 2:
1005         vnc_write(vs, &bg, 2);
1006         vnc_write(vs, &fg, 2);
1007         tight_encode_mono_rect16(vs->tight.tight.buffer, w, h, bg, fg);
1008         break;
1009     default:
1010         vnc_write_u8(vs, bg);
1011         vnc_write_u8(vs, fg);
1012         tight_encode_mono_rect8(vs->tight.tight.buffer, w, h, bg, fg);
1013         break;
1014     }
1015     vs->tight.tight.offset = bytes;
1016
1017     bytes = tight_compress_data(vs, stream, bytes, level, Z_DEFAULT_STRATEGY);
1018     return (bytes >= 0);
1019 }
1020
1021 struct palette_cb_priv {
1022     VncState *vs;
1023     uint8_t *header;
1024 #ifdef CONFIG_VNC_PNG
1025     png_colorp png_palette;
1026 #endif
1027 };
1028
1029 static void write_palette(int idx, uint32_t color, void *opaque)
1030 {
1031     struct palette_cb_priv *priv = opaque;
1032     VncState *vs = priv->vs;
1033     uint32_t bytes = vs->client_pf.bytes_per_pixel;
1034
1035     if (bytes == 4) {
1036         ((uint32_t*)priv->header)[idx] = color;
1037     } else {
1038         ((uint16_t*)priv->header)[idx] = color;
1039     }
1040 }
1041
1042 static bool send_gradient_rect(VncState *vs, int x, int y, int w, int h)
1043 {
1044     int stream = 3;
1045     int level = tight_conf[vs->tight.compression].gradient_zlib_level;
1046     ssize_t bytes;
1047
1048     if (vs->client_pf.bytes_per_pixel == 1) {
1049         return send_full_color_rect(vs, x, y, w, h);
1050     }
1051
1052     vnc_write_u8(vs, (stream | VNC_TIGHT_EXPLICIT_FILTER) << 4);
1053     vnc_write_u8(vs, VNC_TIGHT_FILTER_GRADIENT);
1054
1055     buffer_reserve(&vs->tight.gradient, w * 3 * sizeof (int));
1056
1057     if (vs->tight.pixel24) {
1058         tight_filter_gradient24(vs, vs->tight.tight.buffer, w, h);
1059         bytes = 3;
1060     } else if (vs->client_pf.bytes_per_pixel == 4) {
1061         tight_filter_gradient32(vs, (uint32_t *)vs->tight.tight.buffer, w, h);
1062         bytes = 4;
1063     } else {
1064         tight_filter_gradient16(vs, (uint16_t *)vs->tight.tight.buffer, w, h);
1065         bytes = 2;
1066     }
1067
1068     buffer_reset(&vs->tight.gradient);
1069
1070     bytes = w * h * bytes;
1071     vs->tight.tight.offset = bytes;
1072
1073     bytes = tight_compress_data(vs, stream, bytes,
1074                                 level, Z_FILTERED);
1075     return (bytes >= 0);
1076 }
1077
1078 static int send_palette_rect(VncState *vs, int x, int y,
1079                              int w, int h, VncPalette *palette)
1080 {
1081     int stream = 2;
1082     int level = tight_conf[vs->tight.compression].idx_zlib_level;
1083     int colors;
1084     ssize_t bytes;
1085
1086 #ifdef CONFIG_VNC_PNG
1087     if (tight_can_send_png_rect(vs, w, h)) {
1088         return send_png_rect(vs, x, y, w, h, palette);
1089     }
1090 #endif
1091
1092     colors = palette_size(palette);
1093
1094     vnc_write_u8(vs, (stream | VNC_TIGHT_EXPLICIT_FILTER) << 4);
1095     vnc_write_u8(vs, VNC_TIGHT_FILTER_PALETTE);
1096     vnc_write_u8(vs, colors - 1);
1097
1098     switch (vs->client_pf.bytes_per_pixel) {
1099     case 4:
1100     {
1101         size_t old_offset, offset;
1102         uint32_t header[palette_size(palette)];
1103         struct palette_cb_priv priv = { vs, (uint8_t *)header };
1104
1105         old_offset = vs->output.offset;
1106         palette_iter(palette, write_palette, &priv);
1107         vnc_write(vs, header, sizeof(header));
1108
1109         if (vs->tight.pixel24) {
1110             tight_pack24(vs, vs->output.buffer + old_offset, colors, &offset);
1111             vs->output.offset = old_offset + offset;
1112         }
1113
1114         tight_encode_indexed_rect32(vs->tight.tight.buffer, w * h, palette);
1115         break;
1116     }
1117     case 2:
1118     {
1119         uint16_t header[palette_size(palette)];
1120         struct palette_cb_priv priv = { vs, (uint8_t *)header };
1121
1122         palette_iter(palette, write_palette, &priv);
1123         vnc_write(vs, header, sizeof(header));
1124         tight_encode_indexed_rect16(vs->tight.tight.buffer, w * h, palette);
1125         break;
1126     }
1127     default:
1128         return -1; /* No palette for 8bits colors */
1129         break;
1130     }
1131     bytes = w * h;
1132     vs->tight.tight.offset = bytes;
1133
1134     bytes = tight_compress_data(vs, stream, bytes,
1135                                 level, Z_DEFAULT_STRATEGY);
1136     return (bytes >= 0);
1137 }
1138
1139 /*
1140  * JPEG compression stuff.
1141  */
1142 #ifdef CONFIG_VNC_JPEG
1143 /*
1144  * Destination manager implementation for JPEG library.
1145  */
1146
1147 /* This is called once per encoding */
1148 static void jpeg_init_destination(j_compress_ptr cinfo)
1149 {
1150     VncState *vs = cinfo->client_data;
1151     Buffer *buffer = &vs->tight.jpeg;
1152
1153     cinfo->dest->next_output_byte = (JOCTET *)buffer->buffer + buffer->offset;
1154     cinfo->dest->free_in_buffer = (size_t)(buffer->capacity - buffer->offset);
1155 }
1156
1157 /* This is called when we ran out of buffer (shouldn't happen!) */
1158 static boolean jpeg_empty_output_buffer(j_compress_ptr cinfo)
1159 {
1160     VncState *vs = cinfo->client_data;
1161     Buffer *buffer = &vs->tight.jpeg;
1162
1163     buffer->offset = buffer->capacity;
1164     buffer_reserve(buffer, 2048);
1165     jpeg_init_destination(cinfo);
1166     return TRUE;
1167 }
1168
1169 /* This is called when we are done processing data */
1170 static void jpeg_term_destination(j_compress_ptr cinfo)
1171 {
1172     VncState *vs = cinfo->client_data;
1173     Buffer *buffer = &vs->tight.jpeg;
1174
1175     buffer->offset = buffer->capacity - cinfo->dest->free_in_buffer;
1176 }
1177
1178 static int send_jpeg_rect(VncState *vs, int x, int y, int w, int h, int quality)
1179 {
1180     struct jpeg_compress_struct cinfo;
1181     struct jpeg_error_mgr jerr;
1182     struct jpeg_destination_mgr manager;
1183     pixman_image_t *linebuf;
1184     JSAMPROW row[1];
1185     uint8_t *buf;
1186     int dy;
1187
1188     if (surface_bytes_per_pixel(vs->vd->ds) == 1) {
1189         return send_full_color_rect(vs, x, y, w, h);
1190     }
1191
1192     buffer_reserve(&vs->tight.jpeg, 2048);
1193
1194     cinfo.err = jpeg_std_error(&jerr);
1195     jpeg_create_compress(&cinfo);
1196
1197     cinfo.client_data = vs;
1198     cinfo.image_width = w;
1199     cinfo.image_height = h;
1200     cinfo.input_components = 3;
1201     cinfo.in_color_space = JCS_RGB;
1202
1203     jpeg_set_defaults(&cinfo);
1204     jpeg_set_quality(&cinfo, quality, true);
1205
1206     manager.init_destination = jpeg_init_destination;
1207     manager.empty_output_buffer = jpeg_empty_output_buffer;
1208     manager.term_destination = jpeg_term_destination;
1209     cinfo.dest = &manager;
1210
1211     jpeg_start_compress(&cinfo, true);
1212
1213     linebuf = qemu_pixman_linebuf_create(PIXMAN_BE_r8g8b8, w);
1214     buf = (uint8_t *)pixman_image_get_data(linebuf);
1215     row[0] = buf;
1216     for (dy = 0; dy < h; dy++) {
1217         qemu_pixman_linebuf_fill(linebuf, vs->vd->server, w, x, y + dy);
1218         jpeg_write_scanlines(&cinfo, row, 1);
1219     }
1220     qemu_pixman_image_unref(linebuf);
1221
1222     jpeg_finish_compress(&cinfo);
1223     jpeg_destroy_compress(&cinfo);
1224
1225     vnc_write_u8(vs, VNC_TIGHT_JPEG << 4);
1226
1227     tight_send_compact_size(vs, vs->tight.jpeg.offset);
1228     vnc_write(vs, vs->tight.jpeg.buffer, vs->tight.jpeg.offset);
1229     buffer_reset(&vs->tight.jpeg);
1230
1231     return 1;
1232 }
1233 #endif /* CONFIG_VNC_JPEG */
1234
1235 /*
1236  * PNG compression stuff.
1237  */
1238 #ifdef CONFIG_VNC_PNG
1239 static void write_png_palette(int idx, uint32_t pix, void *opaque)
1240 {
1241     struct palette_cb_priv *priv = opaque;
1242     VncState *vs = priv->vs;
1243     png_colorp color = &priv->png_palette[idx];
1244
1245     if (vs->tight.pixel24)
1246     {
1247         color->red = (pix >> vs->client_pf.rshift) & vs->client_pf.rmax;
1248         color->green = (pix >> vs->client_pf.gshift) & vs->client_pf.gmax;
1249         color->blue = (pix >> vs->client_pf.bshift) & vs->client_pf.bmax;
1250     }
1251     else
1252     {
1253         int red, green, blue;
1254
1255         red = (pix >> vs->client_pf.rshift) & vs->client_pf.rmax;
1256         green = (pix >> vs->client_pf.gshift) & vs->client_pf.gmax;
1257         blue = (pix >> vs->client_pf.bshift) & vs->client_pf.bmax;
1258         color->red = ((red * 255 + vs->client_pf.rmax / 2) /
1259                       vs->client_pf.rmax);
1260         color->green = ((green * 255 + vs->client_pf.gmax / 2) /
1261                         vs->client_pf.gmax);
1262         color->blue = ((blue * 255 + vs->client_pf.bmax / 2) /
1263                        vs->client_pf.bmax);
1264     }
1265 }
1266
1267 static void png_write_data(png_structp png_ptr, png_bytep data,
1268                            png_size_t length)
1269 {
1270     VncState *vs = png_get_io_ptr(png_ptr);
1271
1272     buffer_reserve(&vs->tight.png, vs->tight.png.offset + length);
1273     memcpy(vs->tight.png.buffer + vs->tight.png.offset, data, length);
1274
1275     vs->tight.png.offset += length;
1276 }
1277
1278 static void png_flush_data(png_structp png_ptr)
1279 {
1280 }
1281
1282 static void *vnc_png_malloc(png_structp png_ptr, png_size_t size)
1283 {
1284     return g_malloc(size);
1285 }
1286
1287 static void vnc_png_free(png_structp png_ptr, png_voidp ptr)
1288 {
1289     g_free(ptr);
1290 }
1291
1292 static int send_png_rect(VncState *vs, int x, int y, int w, int h,
1293                          VncPalette *palette)
1294 {
1295     png_byte color_type;
1296     png_structp png_ptr;
1297     png_infop info_ptr;
1298     png_colorp png_palette = NULL;
1299     pixman_image_t *linebuf;
1300     int level = tight_png_conf[vs->tight.compression].png_zlib_level;
1301     int filters = tight_png_conf[vs->tight.compression].png_filters;
1302     uint8_t *buf;
1303     int dy;
1304
1305     png_ptr = png_create_write_struct_2(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL,
1306                                         NULL, vnc_png_malloc, vnc_png_free);
1307
1308     if (png_ptr == NULL)
1309         return -1;
1310
1311     info_ptr = png_create_info_struct(png_ptr);
1312
1313     if (info_ptr == NULL) {
1314         png_destroy_write_struct(&png_ptr, NULL);
1315         return -1;
1316     }
1317
1318     png_set_write_fn(png_ptr, (void *) vs, png_write_data, png_flush_data);
1319     png_set_compression_level(png_ptr, level);
1320     png_set_filter(png_ptr, PNG_FILTER_TYPE_DEFAULT, filters);
1321
1322     if (palette) {
1323         color_type = PNG_COLOR_TYPE_PALETTE;
1324     } else {
1325         color_type = PNG_COLOR_TYPE_RGB;
1326     }
1327
1328     png_set_IHDR(png_ptr, info_ptr, w, h,
1329                  8, color_type, PNG_INTERLACE_NONE,
1330                  PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
1331
1332     if (color_type == PNG_COLOR_TYPE_PALETTE) {
1333         struct palette_cb_priv priv;
1334
1335         png_palette = png_malloc(png_ptr, sizeof(*png_palette) *
1336                                  palette_size(palette));
1337
1338         priv.vs = vs;
1339         priv.png_palette = png_palette;
1340         palette_iter(palette, write_png_palette, &priv);
1341
1342         png_set_PLTE(png_ptr, info_ptr, png_palette, palette_size(palette));
1343
1344         if (vs->client_pf.bytes_per_pixel == 4) {
1345             tight_encode_indexed_rect32(vs->tight.tight.buffer, w * h, palette);
1346         } else {
1347             tight_encode_indexed_rect16(vs->tight.tight.buffer, w * h, palette);
1348         }
1349     }
1350
1351     png_write_info(png_ptr, info_ptr);
1352
1353     buffer_reserve(&vs->tight.png, 2048);
1354     linebuf = qemu_pixman_linebuf_create(PIXMAN_BE_r8g8b8, w);
1355     buf = (uint8_t *)pixman_image_get_data(linebuf);
1356     for (dy = 0; dy < h; dy++)
1357     {
1358         if (color_type == PNG_COLOR_TYPE_PALETTE) {
1359             memcpy(buf, vs->tight.tight.buffer + (dy * w), w);
1360         } else {
1361             qemu_pixman_linebuf_fill(linebuf, vs->vd->server, w, x, y + dy);
1362         }
1363         png_write_row(png_ptr, buf);
1364     }
1365     qemu_pixman_image_unref(linebuf);
1366
1367     png_write_end(png_ptr, NULL);
1368
1369     if (color_type == PNG_COLOR_TYPE_PALETTE) {
1370         png_free(png_ptr, png_palette);
1371     }
1372
1373     png_destroy_write_struct(&png_ptr, &info_ptr);
1374
1375     vnc_write_u8(vs, VNC_TIGHT_PNG << 4);
1376
1377     tight_send_compact_size(vs, vs->tight.png.offset);
1378     vnc_write(vs, vs->tight.png.buffer, vs->tight.png.offset);
1379     buffer_reset(&vs->tight.png);
1380     return 1;
1381 }
1382 #endif /* CONFIG_VNC_PNG */
1383
1384 static void vnc_tight_start(VncState *vs)
1385 {
1386     buffer_reset(&vs->tight.tight);
1387
1388     // make the output buffer be the zlib buffer, so we can compress it later
1389     vs->tight.tmp = vs->output;
1390     vs->output = vs->tight.tight;
1391 }
1392
1393 static void vnc_tight_stop(VncState *vs)
1394 {
1395     // switch back to normal output/zlib buffers
1396     vs->tight.tight = vs->output;
1397     vs->output = vs->tight.tmp;
1398 }
1399
1400 static int send_sub_rect_nojpeg(VncState *vs, int x, int y, int w, int h,
1401                                 int bg, int fg, int colors, VncPalette *palette)
1402 {
1403     int ret;
1404
1405     if (colors == 0) {
1406         if (tight_detect_smooth_image(vs, w, h)) {
1407             ret = send_gradient_rect(vs, x, y, w, h);
1408         } else {
1409             ret = send_full_color_rect(vs, x, y, w, h);
1410         }
1411     } else if (colors == 1) {
1412         ret = send_solid_rect(vs);
1413     } else if (colors == 2) {
1414         ret = send_mono_rect(vs, x, y, w, h, bg, fg);
1415     } else if (colors <= 256) {
1416         ret = send_palette_rect(vs, x, y, w, h, palette);
1417     } else {
1418         ret = 0;
1419     }
1420     return ret;
1421 }
1422
1423 #ifdef CONFIG_VNC_JPEG
1424 static int send_sub_rect_jpeg(VncState *vs, int x, int y, int w, int h,
1425                               int bg, int fg, int colors,
1426                               VncPalette *palette, bool force)
1427 {
1428     int ret;
1429
1430     if (colors == 0) {
1431         if (force || (tight_jpeg_conf[vs->tight.quality].jpeg_full &&
1432                       tight_detect_smooth_image(vs, w, h))) {
1433             int quality = tight_conf[vs->tight.quality].jpeg_quality;
1434
1435             ret = send_jpeg_rect(vs, x, y, w, h, quality);
1436         } else {
1437             ret = send_full_color_rect(vs, x, y, w, h);
1438         }
1439     } else if (colors == 1) {
1440         ret = send_solid_rect(vs);
1441     } else if (colors == 2) {
1442         ret = send_mono_rect(vs, x, y, w, h, bg, fg);
1443     } else if (colors <= 256) {
1444         if (force || (colors > 96 &&
1445                       tight_jpeg_conf[vs->tight.quality].jpeg_idx &&
1446                       tight_detect_smooth_image(vs, w, h))) {
1447             int quality = tight_conf[vs->tight.quality].jpeg_quality;
1448
1449             ret = send_jpeg_rect(vs, x, y, w, h, quality);
1450         } else {
1451             ret = send_palette_rect(vs, x, y, w, h, palette);
1452         }
1453     } else {
1454         ret = 0;
1455     }
1456     return ret;
1457 }
1458 #endif
1459
1460 static int send_sub_rect(VncState *vs, int x, int y, int w, int h)
1461 {
1462     VncPalette *palette = NULL;
1463     uint32_t bg = 0, fg = 0;
1464     int colors;
1465     int ret = 0;
1466 #ifdef CONFIG_VNC_JPEG
1467     bool force_jpeg = false;
1468     bool allow_jpeg = true;
1469 #endif
1470
1471     vnc_framebuffer_update(vs, x, y, w, h, vs->tight.type);
1472
1473     vnc_tight_start(vs);
1474     vnc_raw_send_framebuffer_update(vs, x, y, w, h);
1475     vnc_tight_stop(vs);
1476
1477 #ifdef CONFIG_VNC_JPEG
1478     if (!vs->vd->non_adaptive && vs->tight.quality != (uint8_t)-1) {
1479         double freq = vnc_update_freq(vs, x, y, w, h);
1480
1481         if (freq < tight_jpeg_conf[vs->tight.quality].jpeg_freq_min) {
1482             allow_jpeg = false;
1483         }
1484         if (freq >= tight_jpeg_conf[vs->tight.quality].jpeg_freq_threshold) {
1485             force_jpeg = true;
1486             vnc_sent_lossy_rect(vs, x, y, w, h);
1487         }
1488     }
1489 #endif
1490
1491     colors = tight_fill_palette(vs, x, y, w * h, &bg, &fg, &palette);
1492
1493 #ifdef CONFIG_VNC_JPEG
1494     if (allow_jpeg && vs->tight.quality != (uint8_t)-1) {
1495         ret = send_sub_rect_jpeg(vs, x, y, w, h, bg, fg, colors, palette,
1496                                  force_jpeg);
1497     } else {
1498         ret = send_sub_rect_nojpeg(vs, x, y, w, h, bg, fg, colors, palette);
1499     }
1500 #else
1501     ret = send_sub_rect_nojpeg(vs, x, y, w, h, bg, fg, colors, palette);
1502 #endif
1503
1504     palette_destroy(palette);
1505     return ret;
1506 }
1507
1508 static int send_sub_rect_solid(VncState *vs, int x, int y, int w, int h)
1509 {
1510     vnc_framebuffer_update(vs, x, y, w, h, vs->tight.type);
1511
1512     vnc_tight_start(vs);
1513     vnc_raw_send_framebuffer_update(vs, x, y, w, h);
1514     vnc_tight_stop(vs);
1515
1516     return send_solid_rect(vs);
1517 }
1518
1519 static int send_rect_simple(VncState *vs, int x, int y, int w, int h,
1520                             bool split)
1521 {
1522     int max_size, max_width;
1523     int max_sub_width, max_sub_height;
1524     int dx, dy;
1525     int rw, rh;
1526     int n = 0;
1527
1528     max_size = tight_conf[vs->tight.compression].max_rect_size;
1529     max_width = tight_conf[vs->tight.compression].max_rect_width;
1530
1531     if (split && (w > max_width || w * h > max_size)) {
1532         max_sub_width = (w > max_width) ? max_width : w;
1533         max_sub_height = max_size / max_sub_width;
1534
1535         for (dy = 0; dy < h; dy += max_sub_height) {
1536             for (dx = 0; dx < w; dx += max_width) {
1537                 rw = MIN(max_sub_width, w - dx);
1538                 rh = MIN(max_sub_height, h - dy);
1539                 n += send_sub_rect(vs, x+dx, y+dy, rw, rh);
1540             }
1541         }
1542     } else {
1543         n += send_sub_rect(vs, x, y, w, h);
1544     }
1545
1546     return n;
1547 }
1548
1549 static int find_large_solid_color_rect(VncState *vs, int x, int y,
1550                                        int w, int h, int max_rows)
1551 {
1552     int dx, dy, dw, dh;
1553     int n = 0;
1554
1555     /* Try to find large solid-color areas and send them separately. */
1556
1557     for (dy = y; dy < y + h; dy += VNC_TIGHT_MAX_SPLIT_TILE_SIZE) {
1558
1559         /* If a rectangle becomes too large, send its upper part now. */
1560
1561         if (dy - y >= max_rows) {
1562             n += send_rect_simple(vs, x, y, w, max_rows, true);
1563             y += max_rows;
1564             h -= max_rows;
1565         }
1566
1567         dh = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, (y + h - dy));
1568
1569         for (dx = x; dx < x + w; dx += VNC_TIGHT_MAX_SPLIT_TILE_SIZE) {
1570             uint32_t color_value;
1571             int x_best, y_best, w_best, h_best;
1572
1573             dw = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, (x + w - dx));
1574
1575             if (!check_solid_tile(vs, dx, dy, dw, dh, &color_value, false)) {
1576                 continue ;
1577             }
1578
1579             /* Get dimensions of solid-color area. */
1580
1581             find_best_solid_area(vs, dx, dy, w - (dx - x), h - (dy - y),
1582                                  color_value, &w_best, &h_best);
1583
1584             /* Make sure a solid rectangle is large enough
1585                (or the whole rectangle is of the same color). */
1586
1587             if (w_best * h_best != w * h &&
1588                 w_best * h_best < VNC_TIGHT_MIN_SOLID_SUBRECT_SIZE) {
1589                 continue;
1590             }
1591
1592             /* Try to extend solid rectangle to maximum size. */
1593
1594             x_best = dx; y_best = dy;
1595             extend_solid_area(vs, x, y, w, h, color_value,
1596                               &x_best, &y_best, &w_best, &h_best);
1597
1598             /* Send rectangles at top and left to solid-color area. */
1599
1600             if (y_best != y) {
1601                 n += send_rect_simple(vs, x, y, w, y_best-y, true);
1602             }
1603             if (x_best != x) {
1604                 n += tight_send_framebuffer_update(vs, x, y_best,
1605                                                    x_best-x, h_best);
1606             }
1607
1608             /* Send solid-color rectangle. */
1609             n += send_sub_rect_solid(vs, x_best, y_best, w_best, h_best);
1610
1611             /* Send remaining rectangles (at right and bottom). */
1612
1613             if (x_best + w_best != x + w) {
1614                 n += tight_send_framebuffer_update(vs, x_best+w_best,
1615                                                    y_best,
1616                                                    w-(x_best-x)-w_best,
1617                                                    h_best);
1618             }
1619             if (y_best + h_best != y + h) {
1620                 n += tight_send_framebuffer_update(vs, x, y_best+h_best,
1621                                                    w, h-(y_best-y)-h_best);
1622             }
1623
1624             /* Return after all recursive calls are done. */
1625             return n;
1626         }
1627     }
1628     return n + send_rect_simple(vs, x, y, w, h, true);
1629 }
1630
1631 static int tight_send_framebuffer_update(VncState *vs, int x, int y,
1632                                          int w, int h)
1633 {
1634     int max_rows;
1635
1636     if (vs->client_pf.bytes_per_pixel == 4 && vs->client_pf.rmax == 0xFF &&
1637         vs->client_pf.bmax == 0xFF && vs->client_pf.gmax == 0xFF) {
1638         vs->tight.pixel24 = true;
1639     } else {
1640         vs->tight.pixel24 = false;
1641     }
1642
1643 #ifdef CONFIG_VNC_JPEG
1644     if (vs->tight.quality != (uint8_t)-1) {
1645         double freq = vnc_update_freq(vs, x, y, w, h);
1646
1647         if (freq > tight_jpeg_conf[vs->tight.quality].jpeg_freq_threshold) {
1648             return send_rect_simple(vs, x, y, w, h, false);
1649         }
1650     }
1651 #endif
1652
1653     if (w * h < VNC_TIGHT_MIN_SPLIT_RECT_SIZE) {
1654         return send_rect_simple(vs, x, y, w, h, true);
1655     }
1656
1657     /* Calculate maximum number of rows in one non-solid rectangle. */
1658
1659     max_rows = tight_conf[vs->tight.compression].max_rect_size;
1660     max_rows /= MIN(tight_conf[vs->tight.compression].max_rect_width, w);
1661
1662     return find_large_solid_color_rect(vs, x, y, w, h, max_rows);
1663 }
1664
1665 int vnc_tight_send_framebuffer_update(VncState *vs, int x, int y,
1666                                       int w, int h)
1667 {
1668     vs->tight.type = VNC_ENCODING_TIGHT;
1669     return tight_send_framebuffer_update(vs, x, y, w, h);
1670 }
1671
1672 int vnc_tight_png_send_framebuffer_update(VncState *vs, int x, int y,
1673                                           int w, int h)
1674 {
1675     vs->tight.type = VNC_ENCODING_TIGHT_PNG;
1676     return tight_send_framebuffer_update(vs, x, y, w, h);
1677 }
1678
1679 void vnc_tight_clear(VncState *vs)
1680 {
1681     int i;
1682     for (i=0; i<ARRAY_SIZE(vs->tight.stream); i++) {
1683         if (vs->tight.stream[i].opaque) {
1684             deflateEnd(&vs->tight.stream[i]);
1685         }
1686     }
1687
1688     buffer_free(&vs->tight.tight);
1689     buffer_free(&vs->tight.zlib);
1690     buffer_free(&vs->tight.gradient);
1691 #ifdef CONFIG_VNC_JPEG
1692     buffer_free(&vs->tight.jpeg);
1693 #endif
1694 #ifdef CONFIG_VNC_PNG
1695     buffer_free(&vs->tight.png);
1696 #endif
1697 }