xref: /illumos-kvm-cmd/ui/vnc-enc-tight.c (revision 68396ea9)
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 "config-host.h"
30 
31 #ifdef CONFIG_VNC_PNG
32 #include <png.h>
33 #endif
34 #ifdef CONFIG_VNC_JPEG
35 #include <stdio.h>
36 #include <jpeglib.h>
37 #endif
38 
39 #include "qemu-common.h"
40 
41 #include "bswap.h"
42 #include "qint.h"
43 #include "vnc.h"
44 #include "vnc-enc-tight.h"
45 #include "vnc-palette.h"
46 
47 /* Compression level stuff. The following array contains various
48    encoder parameters for each of 10 compression levels (0..9).
49    Last three parameters correspond to JPEG quality levels (0..9). */
50 
51 static const struct {
52     int max_rect_size, max_rect_width;
53     int mono_min_rect_size, gradient_min_rect_size;
54     int idx_zlib_level, mono_zlib_level, raw_zlib_level, gradient_zlib_level;
55     int gradient_threshold, gradient_threshold24;
56     int idx_max_colors_divisor;
57     int jpeg_quality, jpeg_threshold, jpeg_threshold24;
58 } tight_conf[] = {
59     {   512,   32,   6, 65536, 0, 0, 0, 0,   0,   0,   4,  5, 10000, 23000 },
60     {  2048,  128,   6, 65536, 1, 1, 1, 0,   0,   0,   8, 10,  8000, 18000 },
61     {  6144,  256,   8, 65536, 3, 3, 2, 0,   0,   0,  24, 15,  6500, 15000 },
62     { 10240, 1024,  12, 65536, 5, 5, 3, 0,   0,   0,  32, 25,  5000, 12000 },
63     { 16384, 2048,  12, 65536, 6, 6, 4, 0,   0,   0,  32, 37,  4000, 10000 },
64     { 32768, 2048,  12,  4096, 7, 7, 5, 4, 150, 380,  32, 50,  3000,  8000 },
65     { 65536, 2048,  16,  4096, 7, 7, 6, 4, 170, 420,  48, 60,  2000,  5000 },
66     { 65536, 2048,  16,  4096, 8, 8, 7, 5, 180, 450,  64, 70,  1000,  2500 },
67     { 65536, 2048,  32,  8192, 9, 9, 8, 6, 190, 475,  64, 75,   500,  1200 },
68     { 65536, 2048,  32,  8192, 9, 9, 9, 6, 200, 500,  96, 80,   200,   500 }
69 };
70 
71 
72 static int tight_send_framebuffer_update(VncState *vs, int x, int y,
73                                          int w, int h);
74 
75 #ifdef CONFIG_VNC_PNG
76 static const struct {
77     int png_zlib_level, png_filters;
78 } tight_png_conf[] = {
79     { 0, PNG_NO_FILTERS },
80     { 1, PNG_NO_FILTERS },
81     { 2, PNG_NO_FILTERS },
82     { 3, PNG_NO_FILTERS },
83     { 4, PNG_NO_FILTERS },
84     { 5, PNG_ALL_FILTERS },
85     { 6, PNG_ALL_FILTERS },
86     { 7, PNG_ALL_FILTERS },
87     { 8, PNG_ALL_FILTERS },
88     { 9, PNG_ALL_FILTERS },
89 };
90 
91 static int send_png_rect(VncState *vs, int x, int y, int w, int h,
92                          VncPalette *palette);
93 
tight_can_send_png_rect(VncState * vs,int w,int h)94 static bool tight_can_send_png_rect(VncState *vs, int w, int h)
95 {
96     if (vs->tight.type != VNC_ENCODING_TIGHT_PNG) {
97         return false;
98     }
99 
100     if (ds_get_bytes_per_pixel(vs->ds) == 1 ||
101         vs->clientds.pf.bytes_per_pixel == 1) {
102         return false;
103     }
104 
105     return true;
106 }
107 #endif
108 
109 /*
110  * Code to guess if given rectangle is suitable for smooth image
111  * compression (by applying "gradient" filter or JPEG coder).
112  */
113 
114 static unsigned int
tight_detect_smooth_image24(VncState * vs,int w,int h)115 tight_detect_smooth_image24(VncState *vs, int w, int h)
116 {
117     int off;
118     int x, y, d, dx;
119     unsigned int c;
120     unsigned int stats[256];
121     int pixels = 0;
122     int pix, left[3];
123     unsigned int errors;
124     unsigned char *buf = vs->tight.tight.buffer;
125 
126     /*
127      * If client is big-endian, color samples begin from the second
128      * byte (offset 1) of a 32-bit pixel value.
129      */
130     off = !!(vs->clientds.flags & QEMU_BIG_ENDIAN_FLAG);
131 
132     memset(stats, 0, sizeof (stats));
133 
134     for (y = 0, x = 0; y < h && x < w;) {
135         for (d = 0; d < h - y && d < w - x - VNC_TIGHT_DETECT_SUBROW_WIDTH;
136              d++) {
137             for (c = 0; c < 3; c++) {
138                 left[c] = buf[((y+d)*w+x+d)*4+off+c] & 0xFF;
139             }
140             for (dx = 1; dx <= VNC_TIGHT_DETECT_SUBROW_WIDTH; dx++) {
141                 for (c = 0; c < 3; c++) {
142                     pix = buf[((y+d)*w+x+d+dx)*4+off+c] & 0xFF;
143                     stats[abs(pix - left[c])]++;
144                     left[c] = pix;
145                 }
146                 pixels++;
147             }
148         }
149         if (w > h) {
150             x += h;
151             y = 0;
152         } else {
153             x = 0;
154             y += w;
155         }
156     }
157 
158     /* 95% smooth or more ... */
159     if (stats[0] * 33 / pixels >= 95) {
160         return 0;
161     }
162 
163     errors = 0;
164     for (c = 1; c < 8; c++) {
165         errors += stats[c] * (c * c);
166         if (stats[c] == 0 || stats[c] > stats[c-1] * 2) {
167             return 0;
168         }
169     }
170     for (; c < 256; c++) {
171         errors += stats[c] * (c * c);
172     }
173     errors /= (pixels * 3 - stats[0]);
174 
175     return errors;
176 }
177 
178 #define DEFINE_DETECT_FUNCTION(bpp)                                     \
179                                                                         \
180     static unsigned int                                                 \
181     tight_detect_smooth_image##bpp(VncState *vs, int w, int h) {        \
182         bool endian;                                                    \
183         uint##bpp##_t pix;                                              \
184         int max[3], shift[3];                                           \
185         int x, y, d, dx;                                                \
186         unsigned int c;                                                 \
187         unsigned int stats[256];                                        \
188         int pixels = 0;                                                 \
189         int sample, sum, left[3];                                       \
190         unsigned int errors;                                            \
191         unsigned char *buf = vs->tight.tight.buffer;                    \
192                                                                         \
193         endian = ((vs->clientds.flags & QEMU_BIG_ENDIAN_FLAG) !=        \
194                   (vs->ds->surface->flags & QEMU_BIG_ENDIAN_FLAG));     \
195                                                                         \
196                                                                         \
197         max[0] = vs->clientds.pf.rmax;                                  \
198         max[1] = vs->clientds.pf.gmax;                                  \
199         max[2] = vs->clientds.pf.bmax;                                  \
200         shift[0] = vs->clientds.pf.rshift;                              \
201         shift[1] = vs->clientds.pf.gshift;                              \
202         shift[2] = vs->clientds.pf.bshift;                              \
203                                                                         \
204         memset(stats, 0, sizeof(stats));                                \
205                                                                         \
206         y = 0, x = 0;                                                   \
207         while (y < h && x < w) {                                        \
208             for (d = 0; d < h - y &&                                    \
209                      d < w - x - VNC_TIGHT_DETECT_SUBROW_WIDTH; d++) {  \
210                 pix = ((uint##bpp##_t *)buf)[(y+d)*w+x+d];              \
211                 if (endian) {                                           \
212                     pix = bswap##bpp(pix);                              \
213                 }                                                       \
214                 for (c = 0; c < 3; c++) {                               \
215                     left[c] = (int)(pix >> shift[c] & max[c]);          \
216                 }                                                       \
217                 for (dx = 1; dx <= VNC_TIGHT_DETECT_SUBROW_WIDTH;       \
218                      dx++) {                                            \
219                     pix = ((uint##bpp##_t *)buf)[(y+d)*w+x+d+dx];       \
220                     if (endian) {                                       \
221                         pix = bswap##bpp(pix);                          \
222                     }                                                   \
223                     sum = 0;                                            \
224                     for (c = 0; c < 3; c++) {                           \
225                         sample = (int)(pix >> shift[c] & max[c]);       \
226                         sum += abs(sample - left[c]);                   \
227                         left[c] = sample;                               \
228                     }                                                   \
229                     if (sum > 255) {                                    \
230                         sum = 255;                                      \
231                     }                                                   \
232                     stats[sum]++;                                       \
233                     pixels++;                                           \
234                 }                                                       \
235             }                                                           \
236             if (w > h) {                                                \
237                 x += h;                                                 \
238                 y = 0;                                                  \
239             } else {                                                    \
240                 x = 0;                                                  \
241                 y += w;                                                 \
242             }                                                           \
243         }                                                               \
244                                                                         \
245         if ((stats[0] + stats[1]) * 100 / pixels >= 90) {               \
246             return 0;                                                   \
247         }                                                               \
248                                                                         \
249         errors = 0;                                                     \
250         for (c = 1; c < 8; c++) {                                       \
251             errors += stats[c] * (c * c);                               \
252             if (stats[c] == 0 || stats[c] > stats[c-1] * 2) {           \
253                 return 0;                                               \
254             }                                                           \
255         }                                                               \
256         for (; c < 256; c++) {                                          \
257             errors += stats[c] * (c * c);                               \
258         }                                                               \
259         errors /= (pixels - stats[0]);                                  \
260                                                                         \
261         return errors;                                                  \
262     }
263 
264 DEFINE_DETECT_FUNCTION(16)
265 DEFINE_DETECT_FUNCTION(32)
266 
267 static int
tight_detect_smooth_image(VncState * vs,int w,int h)268 tight_detect_smooth_image(VncState *vs, int w, int h)
269 {
270     unsigned int errors;
271     int compression = vs->tight.compression;
272     int quality = vs->tight.quality;
273 
274     if (!vs->vd->lossy) {
275         return 0;
276     }
277 
278     if (ds_get_bytes_per_pixel(vs->ds) == 1 ||
279         vs->clientds.pf.bytes_per_pixel == 1 ||
280         w < VNC_TIGHT_DETECT_MIN_WIDTH || h < VNC_TIGHT_DETECT_MIN_HEIGHT) {
281         return 0;
282     }
283 
284     if (vs->tight.quality != (uint8_t)-1) {
285         if (w * h < VNC_TIGHT_JPEG_MIN_RECT_SIZE) {
286             return 0;
287         }
288     } else {
289         if (w * h < tight_conf[compression].gradient_min_rect_size) {
290             return 0;
291         }
292     }
293 
294     if (vs->clientds.pf.bytes_per_pixel == 4) {
295         if (vs->tight.pixel24) {
296             errors = tight_detect_smooth_image24(vs, w, h);
297             if (vs->tight.quality != (uint8_t)-1) {
298                 return (errors < tight_conf[quality].jpeg_threshold24);
299             }
300             return (errors < tight_conf[compression].gradient_threshold24);
301         } else {
302             errors = tight_detect_smooth_image32(vs, w, h);
303         }
304     } else {
305         errors = tight_detect_smooth_image16(vs, w, h);
306     }
307     if (quality != -1) {
308         return (errors < tight_conf[quality].jpeg_threshold);
309     }
310     return (errors < tight_conf[compression].gradient_threshold);
311 }
312 
313 /*
314  * Code to determine how many different colors used in rectangle.
315  */
316 #define DEFINE_FILL_PALETTE_FUNCTION(bpp)                               \
317                                                                         \
318     static int                                                          \
319     tight_fill_palette##bpp(VncState *vs, int x, int y,                 \
320                             int max, size_t count,                      \
321                             uint32_t *bg, uint32_t *fg,                 \
322                             VncPalette **palette) {                     \
323         uint##bpp##_t *data;                                            \
324         uint##bpp##_t c0, c1, ci;                                       \
325         int i, n0, n1;                                                  \
326                                                                         \
327         data = (uint##bpp##_t *)vs->tight.tight.buffer;                 \
328                                                                         \
329         c0 = data[0];                                                   \
330         i = 1;                                                          \
331         while (i < count && data[i] == c0)                              \
332             i++;                                                        \
333         if (i >= count) {                                               \
334             *bg = *fg = c0;                                             \
335             return 1;                                                   \
336         }                                                               \
337                                                                         \
338         if (max < 2) {                                                  \
339             return 0;                                                   \
340         }                                                               \
341                                                                         \
342         n0 = i;                                                         \
343         c1 = data[i];                                                   \
344         n1 = 0;                                                         \
345         for (i++; i < count; i++) {                                     \
346             ci = data[i];                                               \
347             if (ci == c0) {                                             \
348                 n0++;                                                   \
349             } else if (ci == c1) {                                      \
350                 n1++;                                                   \
351             } else                                                      \
352                 break;                                                  \
353         }                                                               \
354         if (i >= count) {                                               \
355             if (n0 > n1) {                                              \
356                 *bg = (uint32_t)c0;                                     \
357                 *fg = (uint32_t)c1;                                     \
358             } else {                                                    \
359                 *bg = (uint32_t)c1;                                     \
360                 *fg = (uint32_t)c0;                                     \
361             }                                                           \
362             return 2;                                                   \
363         }                                                               \
364                                                                         \
365         if (max == 2) {                                                 \
366             return 0;                                                   \
367         }                                                               \
368                                                                         \
369         *palette = palette_new(max, bpp);                               \
370         palette_put(*palette, c0);                                      \
371         palette_put(*palette, c1);                                      \
372         palette_put(*palette, ci);                                      \
373                                                                         \
374         for (i++; i < count; i++) {                                     \
375             if (data[i] == ci) {                                        \
376                 continue;                                               \
377             } else {                                                    \
378                 ci = data[i];                                           \
379                 if (!palette_put(*palette, (uint32_t)ci)) {             \
380                     return 0;                                           \
381                 }                                                       \
382             }                                                           \
383         }                                                               \
384                                                                         \
385         return palette_size(*palette);                                  \
386     }
387 
388 DEFINE_FILL_PALETTE_FUNCTION(8)
389 DEFINE_FILL_PALETTE_FUNCTION(16)
390 DEFINE_FILL_PALETTE_FUNCTION(32)
391 
tight_fill_palette(VncState * vs,int x,int y,size_t count,uint32_t * bg,uint32_t * fg,VncPalette ** palette)392 static int tight_fill_palette(VncState *vs, int x, int y,
393                               size_t count, uint32_t *bg, uint32_t *fg,
394                               VncPalette **palette)
395 {
396     int max;
397 
398     max = count / tight_conf[vs->tight.compression].idx_max_colors_divisor;
399     if (max < 2 &&
400         count >= tight_conf[vs->tight.compression].mono_min_rect_size) {
401         max = 2;
402     }
403     if (max >= 256) {
404         max = 256;
405     }
406 
407     switch(vs->clientds.pf.bytes_per_pixel) {
408     case 4:
409         return tight_fill_palette32(vs, x, y, max, count, bg, fg, palette);
410     case 2:
411         return tight_fill_palette16(vs, x, y, max, count, bg, fg, palette);
412     default:
413         max = 2;
414         return tight_fill_palette8(vs, x, y, max, count, bg, fg, palette);
415     }
416     return 0;
417 }
418 
419 /*
420  * Converting truecolor samples into palette indices.
421  */
422 #define DEFINE_IDX_ENCODE_FUNCTION(bpp)                                 \
423                                                                         \
424     static void                                                         \
425     tight_encode_indexed_rect##bpp(uint8_t *buf, int count,             \
426                                    VncPalette *palette) {               \
427         uint##bpp##_t *src;                                             \
428         uint##bpp##_t rgb;                                              \
429         int i, rep;                                                     \
430         uint8_t idx;                                                    \
431                                                                         \
432         src = (uint##bpp##_t *) buf;                                    \
433                                                                         \
434         for (i = 0; i < count; i++) {                                   \
435                                                                         \
436             rgb = *src++;                                               \
437             rep = 0;                                                    \
438             while (i < count && *src == rgb) {                          \
439                 rep++, src++, i++;                                      \
440             }                                                           \
441             idx = palette_idx(palette, rgb);                            \
442             /*                                                          \
443              * Should never happen, but don't break everything          \
444              * if it does, use the first color instead                  \
445              */                                                         \
446             if (idx == (uint8_t)-1) {                                   \
447                 idx = 0;                                                \
448             }                                                           \
449             while (rep >= 0) {                                          \
450                 *buf++ = idx;                                           \
451                 rep--;                                                  \
452             }                                                           \
453         }                                                               \
454     }
455 
456 DEFINE_IDX_ENCODE_FUNCTION(16)
457 DEFINE_IDX_ENCODE_FUNCTION(32)
458 
459 #define DEFINE_MONO_ENCODE_FUNCTION(bpp)                                \
460                                                                         \
461     static void                                                         \
462     tight_encode_mono_rect##bpp(uint8_t *buf, int w, int h,             \
463                                 uint##bpp##_t bg, uint##bpp##_t fg) {   \
464         uint##bpp##_t *ptr;                                             \
465         unsigned int value, mask;                                       \
466         int aligned_width;                                              \
467         int x, y, bg_bits;                                              \
468                                                                         \
469         ptr = (uint##bpp##_t *) buf;                                    \
470         aligned_width = w - w % 8;                                      \
471                                                                         \
472         for (y = 0; y < h; y++) {                                       \
473             for (x = 0; x < aligned_width; x += 8) {                    \
474                 for (bg_bits = 0; bg_bits < 8; bg_bits++) {             \
475                     if (*ptr++ != bg) {                                 \
476                         break;                                          \
477                     }                                                   \
478                 }                                                       \
479                 if (bg_bits == 8) {                                     \
480                     *buf++ = 0;                                         \
481                     continue;                                           \
482                 }                                                       \
483                 mask = 0x80 >> bg_bits;                                 \
484                 value = mask;                                           \
485                 for (bg_bits++; bg_bits < 8; bg_bits++) {               \
486                     mask >>= 1;                                         \
487                     if (*ptr++ != bg) {                                 \
488                         value |= mask;                                  \
489                     }                                                   \
490                 }                                                       \
491                 *buf++ = (uint8_t)value;                                \
492             }                                                           \
493                                                                         \
494             mask = 0x80;                                                \
495             value = 0;                                                  \
496             if (x >= w) {                                               \
497                 continue;                                               \
498             }                                                           \
499                                                                         \
500             for (; x < w; x++) {                                        \
501                 if (*ptr++ != bg) {                                     \
502                     value |= mask;                                      \
503                 }                                                       \
504                 mask >>= 1;                                             \
505             }                                                           \
506             *buf++ = (uint8_t)value;                                    \
507         }                                                               \
508     }
509 
510 DEFINE_MONO_ENCODE_FUNCTION(8)
511 DEFINE_MONO_ENCODE_FUNCTION(16)
512 DEFINE_MONO_ENCODE_FUNCTION(32)
513 
514 /*
515  * ``Gradient'' filter for 24-bit color samples.
516  * Should be called only when redMax, greenMax and blueMax are 255.
517  * Color components assumed to be byte-aligned.
518  */
519 
520 static void
tight_filter_gradient24(VncState * vs,uint8_t * buf,int w,int h)521 tight_filter_gradient24(VncState *vs, uint8_t *buf, int w, int h)
522 {
523     uint32_t *buf32;
524     uint32_t pix32;
525     int shift[3];
526     int *prev;
527     int here[3], upper[3], left[3], upperleft[3];
528     int prediction;
529     int x, y, c;
530 
531     buf32 = (uint32_t *)buf;
532     memset(vs->tight.gradient.buffer, 0, w * 3 * sizeof(int));
533 
534     if ((vs->clientds.flags & QEMU_BIG_ENDIAN_FLAG) ==
535         (vs->ds->surface->flags & QEMU_BIG_ENDIAN_FLAG)) {
536         shift[0] = vs->clientds.pf.rshift;
537         shift[1] = vs->clientds.pf.gshift;
538         shift[2] = vs->clientds.pf.bshift;
539     } else {
540         shift[0] = 24 - vs->clientds.pf.rshift;
541         shift[1] = 24 - vs->clientds.pf.gshift;
542         shift[2] = 24 - vs->clientds.pf.bshift;
543     }
544 
545     for (y = 0; y < h; y++) {
546         for (c = 0; c < 3; c++) {
547             upper[c] = 0;
548             here[c] = 0;
549         }
550         prev = (int *)vs->tight.gradient.buffer;
551         for (x = 0; x < w; x++) {
552             pix32 = *buf32++;
553             for (c = 0; c < 3; c++) {
554                 upperleft[c] = upper[c];
555                 left[c] = here[c];
556                 upper[c] = *prev;
557                 here[c] = (int)(pix32 >> shift[c] & 0xFF);
558                 *prev++ = here[c];
559 
560                 prediction = left[c] + upper[c] - upperleft[c];
561                 if (prediction < 0) {
562                     prediction = 0;
563                 } else if (prediction > 0xFF) {
564                     prediction = 0xFF;
565                 }
566                 *buf++ = (char)(here[c] - prediction);
567             }
568         }
569     }
570 }
571 
572 
573 /*
574  * ``Gradient'' filter for other color depths.
575  */
576 
577 #define DEFINE_GRADIENT_FILTER_FUNCTION(bpp)                            \
578                                                                         \
579     static void                                                         \
580     tight_filter_gradient##bpp(VncState *vs, uint##bpp##_t *buf,        \
581                                int w, int h) {                          \
582         uint##bpp##_t pix, diff;                                        \
583         bool endian;                                                    \
584         int *prev;                                                      \
585         int max[3], shift[3];                                           \
586         int here[3], upper[3], left[3], upperleft[3];                   \
587         int prediction;                                                 \
588         int x, y, c;                                                    \
589                                                                         \
590         memset (vs->tight.gradient.buffer, 0, w * 3 * sizeof(int));     \
591                                                                         \
592         endian = ((vs->clientds.flags & QEMU_BIG_ENDIAN_FLAG) !=        \
593                   (vs->ds->surface->flags & QEMU_BIG_ENDIAN_FLAG));     \
594                                                                         \
595         max[0] = vs->clientds.pf.rmax;                                  \
596         max[1] = vs->clientds.pf.gmax;                                  \
597         max[2] = vs->clientds.pf.bmax;                                  \
598         shift[0] = vs->clientds.pf.rshift;                              \
599         shift[1] = vs->clientds.pf.gshift;                              \
600         shift[2] = vs->clientds.pf.bshift;                              \
601                                                                         \
602         for (y = 0; y < h; y++) {                                       \
603             for (c = 0; c < 3; c++) {                                   \
604                 upper[c] = 0;                                           \
605                 here[c] = 0;                                            \
606             }                                                           \
607             prev = (int *)vs->tight.gradient.buffer;                    \
608             for (x = 0; x < w; x++) {                                   \
609                 pix = *buf;                                             \
610                 if (endian) {                                           \
611                     pix = bswap##bpp(pix);                              \
612                 }                                                       \
613                 diff = 0;                                               \
614                 for (c = 0; c < 3; c++) {                               \
615                     upperleft[c] = upper[c];                            \
616                     left[c] = here[c];                                  \
617                     upper[c] = *prev;                                   \
618                     here[c] = (int)(pix >> shift[c] & max[c]);          \
619                     *prev++ = here[c];                                  \
620                                                                         \
621                     prediction = left[c] + upper[c] - upperleft[c];     \
622                     if (prediction < 0) {                               \
623                         prediction = 0;                                 \
624                     } else if (prediction > max[c]) {                   \
625                         prediction = max[c];                            \
626                     }                                                   \
627                     diff |= ((here[c] - prediction) & max[c])           \
628                         << shift[c];                                    \
629                 }                                                       \
630                 if (endian) {                                           \
631                     diff = bswap##bpp(diff);                            \
632                 }                                                       \
633                 *buf++ = diff;                                          \
634             }                                                           \
635         }                                                               \
636     }
637 
638 DEFINE_GRADIENT_FILTER_FUNCTION(16)
639 DEFINE_GRADIENT_FILTER_FUNCTION(32)
640 
641 /*
642  * Check if a rectangle is all of the same color. If needSameColor is
643  * set to non-zero, then also check that its color equals to the
644  * *colorPtr value. The result is 1 if the test is successful, and in
645  * that case new color will be stored in *colorPtr.
646  */
647 
648 #define DEFINE_CHECK_SOLID_FUNCTION(bpp)                                \
649                                                                         \
650     static bool                                                         \
651     check_solid_tile##bpp(VncState *vs, int x, int y, int w, int h,     \
652                           uint32_t* color, bool samecolor)              \
653     {                                                                   \
654         VncDisplay *vd = vs->vd;                                        \
655         uint##bpp##_t *fbptr;                                           \
656         uint##bpp##_t c;                                                \
657         int dx, dy;                                                     \
658                                                                         \
659         fbptr = (uint##bpp##_t *)                                       \
660             (vd->server->data + y * ds_get_linesize(vs->ds) +           \
661              x * ds_get_bytes_per_pixel(vs->ds));                       \
662                                                                         \
663         c = *fbptr;                                                     \
664         if (samecolor && (uint32_t)c != *color) {                       \
665             return false;                                               \
666         }                                                               \
667                                                                         \
668         for (dy = 0; dy < h; dy++) {                                    \
669             for (dx = 0; dx < w; dx++) {                                \
670                 if (c != fbptr[dx]) {                                   \
671                     return false;                                       \
672                 }                                                       \
673             }                                                           \
674             fbptr = (uint##bpp##_t *)                                   \
675                 ((uint8_t *)fbptr + ds_get_linesize(vs->ds));           \
676         }                                                               \
677                                                                         \
678         *color = (uint32_t)c;                                           \
679         return true;                                                    \
680     }
681 
682 DEFINE_CHECK_SOLID_FUNCTION(32)
683 DEFINE_CHECK_SOLID_FUNCTION(16)
684 DEFINE_CHECK_SOLID_FUNCTION(8)
685 
check_solid_tile(VncState * vs,int x,int y,int w,int h,uint32_t * color,bool samecolor)686 static bool check_solid_tile(VncState *vs, int x, int y, int w, int h,
687                              uint32_t* color, bool samecolor)
688 {
689     VncDisplay *vd = vs->vd;
690 
691     switch(vd->server->pf.bytes_per_pixel) {
692     case 4:
693         return check_solid_tile32(vs, x, y, w, h, color, samecolor);
694     case 2:
695         return check_solid_tile16(vs, x, y, w, h, color, samecolor);
696     default:
697         return check_solid_tile8(vs, x, y, w, h, color, samecolor);
698     }
699 }
700 
find_best_solid_area(VncState * vs,int x,int y,int w,int h,uint32_t color,int * w_ptr,int * h_ptr)701 static void find_best_solid_area(VncState *vs, int x, int y, int w, int h,
702                                  uint32_t color, int *w_ptr, int *h_ptr)
703 {
704     int dx, dy, dw, dh;
705     int w_prev;
706     int w_best = 0, h_best = 0;
707 
708     w_prev = w;
709 
710     for (dy = y; dy < y + h; dy += VNC_TIGHT_MAX_SPLIT_TILE_SIZE) {
711 
712         dh = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, y + h - dy);
713         dw = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, w_prev);
714 
715         if (!check_solid_tile(vs, x, dy, dw, dh, &color, true)) {
716             break;
717         }
718 
719         for (dx = x + dw; dx < x + w_prev;) {
720             dw = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, x + w_prev - dx);
721 
722             if (!check_solid_tile(vs, dx, dy, dw, dh, &color, true)) {
723                 break;
724             }
725             dx += dw;
726         }
727 
728         w_prev = dx - x;
729         if (w_prev * (dy + dh - y) > w_best * h_best) {
730             w_best = w_prev;
731             h_best = dy + dh - y;
732         }
733     }
734 
735     *w_ptr = w_best;
736     *h_ptr = h_best;
737 }
738 
extend_solid_area(VncState * vs,int x,int y,int w,int h,uint32_t color,int * x_ptr,int * y_ptr,int * w_ptr,int * h_ptr)739 static void extend_solid_area(VncState *vs, int x, int y, int w, int h,
740                               uint32_t color, int *x_ptr, int *y_ptr,
741                               int *w_ptr, int *h_ptr)
742 {
743     int cx, cy;
744 
745     /* Try to extend the area upwards. */
746     for ( cy = *y_ptr - 1;
747           cy >= y && check_solid_tile(vs, *x_ptr, cy, *w_ptr, 1, &color, true);
748           cy-- );
749     *h_ptr += *y_ptr - (cy + 1);
750     *y_ptr = cy + 1;
751 
752     /* ... downwards. */
753     for ( cy = *y_ptr + *h_ptr;
754           cy < y + h &&
755               check_solid_tile(vs, *x_ptr, cy, *w_ptr, 1, &color, true);
756           cy++ );
757     *h_ptr += cy - (*y_ptr + *h_ptr);
758 
759     /* ... to the left. */
760     for ( cx = *x_ptr - 1;
761           cx >= x && check_solid_tile(vs, cx, *y_ptr, 1, *h_ptr, &color, true);
762           cx-- );
763     *w_ptr += *x_ptr - (cx + 1);
764     *x_ptr = cx + 1;
765 
766     /* ... to the right. */
767     for ( cx = *x_ptr + *w_ptr;
768           cx < x + w &&
769               check_solid_tile(vs, cx, *y_ptr, 1, *h_ptr, &color, true);
770           cx++ );
771     *w_ptr += cx - (*x_ptr + *w_ptr);
772 }
773 
tight_init_stream(VncState * vs,int stream_id,int level,int strategy)774 static int tight_init_stream(VncState *vs, int stream_id,
775                              int level, int strategy)
776 {
777     z_streamp zstream = &vs->tight.stream[stream_id];
778 
779     if (zstream->opaque == NULL) {
780         int err;
781 
782         VNC_DEBUG("VNC: TIGHT: initializing zlib stream %d\n", stream_id);
783         VNC_DEBUG("VNC: TIGHT: opaque = %p | vs = %p\n", zstream->opaque, vs);
784         zstream->zalloc = vnc_zlib_zalloc;
785         zstream->zfree = vnc_zlib_zfree;
786 
787         err = deflateInit2(zstream, level, Z_DEFLATED, MAX_WBITS,
788                            MAX_MEM_LEVEL, strategy);
789 
790         if (err != Z_OK) {
791             fprintf(stderr, "VNC: error initializing zlib\n");
792             return -1;
793         }
794 
795         vs->tight.levels[stream_id] = level;
796         zstream->opaque = vs;
797     }
798 
799     if (vs->tight.levels[stream_id] != level) {
800         if (deflateParams(zstream, level, strategy) != Z_OK) {
801             return -1;
802         }
803         vs->tight.levels[stream_id] = level;
804     }
805     return 0;
806 }
807 
tight_send_compact_size(VncState * vs,size_t len)808 static void tight_send_compact_size(VncState *vs, size_t len)
809 {
810     int lpc = 0;
811     int bytes = 0;
812     char buf[3] = {0, 0, 0};
813 
814     buf[bytes++] = len & 0x7F;
815     if (len > 0x7F) {
816         buf[bytes-1] |= 0x80;
817         buf[bytes++] = (len >> 7) & 0x7F;
818         if (len > 0x3FFF) {
819             buf[bytes-1] |= 0x80;
820             buf[bytes++] = (len >> 14) & 0xFF;
821         }
822     }
823     for (lpc = 0; lpc < bytes; lpc++) {
824         vnc_write_u8(vs, buf[lpc]);
825     }
826 }
827 
tight_compress_data(VncState * vs,int stream_id,size_t bytes,int level,int strategy)828 static int tight_compress_data(VncState *vs, int stream_id, size_t bytes,
829                                int level, int strategy)
830 {
831     z_streamp zstream = &vs->tight.stream[stream_id];
832     int previous_out;
833 
834     if (bytes < VNC_TIGHT_MIN_TO_COMPRESS) {
835         vnc_write(vs, vs->tight.tight.buffer, vs->tight.tight.offset);
836         return bytes;
837     }
838 
839     if (tight_init_stream(vs, stream_id, level, strategy)) {
840         return -1;
841     }
842 
843     /* reserve memory in output buffer */
844     buffer_reserve(&vs->tight.zlib, bytes + 64);
845 
846     /* set pointers */
847     zstream->next_in = vs->tight.tight.buffer;
848     zstream->avail_in = vs->tight.tight.offset;
849     zstream->next_out = vs->tight.zlib.buffer + vs->tight.zlib.offset;
850     zstream->avail_out = vs->tight.zlib.capacity - vs->tight.zlib.offset;
851     previous_out = zstream->avail_out;
852     zstream->data_type = Z_BINARY;
853 
854     /* start encoding */
855     if (deflate(zstream, Z_SYNC_FLUSH) != Z_OK) {
856         fprintf(stderr, "VNC: error during tight compression\n");
857         return -1;
858     }
859 
860     vs->tight.zlib.offset = vs->tight.zlib.capacity - zstream->avail_out;
861     /* ...how much data has actually been produced by deflate() */
862     bytes = previous_out - zstream->avail_out;
863 
864     tight_send_compact_size(vs, bytes);
865     vnc_write(vs, vs->tight.zlib.buffer, bytes);
866 
867     buffer_reset(&vs->tight.zlib);
868 
869     return bytes;
870 }
871 
872 /*
873  * Subencoding implementations.
874  */
tight_pack24(VncState * vs,uint8_t * buf,size_t count,size_t * ret)875 static void tight_pack24(VncState *vs, uint8_t *buf, size_t count, size_t *ret)
876 {
877     uint32_t *buf32;
878     uint32_t pix;
879     int rshift, gshift, bshift;
880 
881     buf32 = (uint32_t *)buf;
882 
883     if ((vs->clientds.flags & QEMU_BIG_ENDIAN_FLAG) ==
884         (vs->ds->surface->flags & QEMU_BIG_ENDIAN_FLAG)) {
885         rshift = vs->clientds.pf.rshift;
886         gshift = vs->clientds.pf.gshift;
887         bshift = vs->clientds.pf.bshift;
888     } else {
889         rshift = 24 - vs->clientds.pf.rshift;
890         gshift = 24 - vs->clientds.pf.gshift;
891         bshift = 24 - vs->clientds.pf.bshift;
892     }
893 
894     if (ret) {
895         *ret = count * 3;
896     }
897 
898     while (count--) {
899         pix = *buf32++;
900         *buf++ = (char)(pix >> rshift);
901         *buf++ = (char)(pix >> gshift);
902         *buf++ = (char)(pix >> bshift);
903     }
904 }
905 
send_full_color_rect(VncState * vs,int x,int y,int w,int h)906 static int send_full_color_rect(VncState *vs, int x, int y, int w, int h)
907 {
908     int stream = 0;
909     ssize_t bytes;
910 
911 #ifdef CONFIG_VNC_PNG
912     if (tight_can_send_png_rect(vs, w, h)) {
913         return send_png_rect(vs, x, y, w, h, NULL);
914     }
915 #endif
916 
917     vnc_write_u8(vs, stream << 4); /* no flushing, no filter */
918 
919     if (vs->tight.pixel24) {
920         tight_pack24(vs, vs->tight.tight.buffer, w * h, &vs->tight.tight.offset);
921         bytes = 3;
922     } else {
923         bytes = vs->clientds.pf.bytes_per_pixel;
924     }
925 
926     bytes = tight_compress_data(vs, stream, w * h * bytes,
927                                 tight_conf[vs->tight.compression].raw_zlib_level,
928                                 Z_DEFAULT_STRATEGY);
929 
930     return (bytes >= 0);
931 }
932 
send_solid_rect(VncState * vs)933 static int send_solid_rect(VncState *vs)
934 {
935     size_t bytes;
936 
937     vnc_write_u8(vs, VNC_TIGHT_FILL << 4); /* no flushing, no filter */
938 
939     if (vs->tight.pixel24) {
940         tight_pack24(vs, vs->tight.tight.buffer, 1, &vs->tight.tight.offset);
941         bytes = 3;
942     } else {
943         bytes = vs->clientds.pf.bytes_per_pixel;
944     }
945 
946     vnc_write(vs, vs->tight.tight.buffer, bytes);
947     return 1;
948 }
949 
send_mono_rect(VncState * vs,int x,int y,int w,int h,uint32_t bg,uint32_t fg)950 static int send_mono_rect(VncState *vs, int x, int y,
951                           int w, int h, uint32_t bg, uint32_t fg)
952 {
953     ssize_t bytes;
954     int stream = 1;
955     int level = tight_conf[vs->tight.compression].mono_zlib_level;
956 
957 #ifdef CONFIG_VNC_PNG
958     if (tight_can_send_png_rect(vs, w, h)) {
959         int ret;
960         int bpp = vs->clientds.pf.bytes_per_pixel * 8;
961         VncPalette *palette = palette_new(2, bpp);
962 
963         palette_put(palette, bg);
964         palette_put(palette, fg);
965         ret = send_png_rect(vs, x, y, w, h, palette);
966         palette_destroy(palette);
967         return ret;
968     }
969 #endif
970 
971     bytes = ((w + 7) / 8) * h;
972 
973     vnc_write_u8(vs, (stream | VNC_TIGHT_EXPLICIT_FILTER) << 4);
974     vnc_write_u8(vs, VNC_TIGHT_FILTER_PALETTE);
975     vnc_write_u8(vs, 1);
976 
977     switch(vs->clientds.pf.bytes_per_pixel) {
978     case 4:
979     {
980         uint32_t buf[2] = {bg, fg};
981         size_t ret = sizeof (buf);
982 
983         if (vs->tight.pixel24) {
984             tight_pack24(vs, (unsigned char*)buf, 2, &ret);
985         }
986         vnc_write(vs, buf, ret);
987 
988         tight_encode_mono_rect32(vs->tight.tight.buffer, w, h, bg, fg);
989         break;
990     }
991     case 2:
992         vnc_write(vs, &bg, 2);
993         vnc_write(vs, &fg, 2);
994         tight_encode_mono_rect16(vs->tight.tight.buffer, w, h, bg, fg);
995         break;
996     default:
997         vnc_write_u8(vs, bg);
998         vnc_write_u8(vs, fg);
999         tight_encode_mono_rect8(vs->tight.tight.buffer, w, h, bg, fg);
1000         break;
1001     }
1002     vs->tight.tight.offset = bytes;
1003 
1004     bytes = tight_compress_data(vs, stream, bytes, level, Z_DEFAULT_STRATEGY);
1005     return (bytes >= 0);
1006 }
1007 
1008 struct palette_cb_priv {
1009     VncState *vs;
1010     uint8_t *header;
1011 #ifdef CONFIG_VNC_PNG
1012     png_colorp png_palette;
1013 #endif
1014 };
1015 
write_palette(int idx,uint32_t color,void * opaque)1016 static void write_palette(int idx, uint32_t color, void *opaque)
1017 {
1018     struct palette_cb_priv *priv = opaque;
1019     VncState *vs = priv->vs;
1020     uint32_t bytes = vs->clientds.pf.bytes_per_pixel;
1021 
1022     if (bytes == 4) {
1023         ((uint32_t*)priv->header)[idx] = color;
1024     } else {
1025         ((uint16_t*)priv->header)[idx] = color;
1026     }
1027 }
1028 
send_gradient_rect(VncState * vs,int x,int y,int w,int h)1029 static bool send_gradient_rect(VncState *vs, int x, int y, int w, int h)
1030 {
1031     int stream = 3;
1032     int level = tight_conf[vs->tight.compression].gradient_zlib_level;
1033     ssize_t bytes;
1034 
1035     if (vs->clientds.pf.bytes_per_pixel == 1)
1036         return send_full_color_rect(vs, x, y, w, h);
1037 
1038     vnc_write_u8(vs, (stream | VNC_TIGHT_EXPLICIT_FILTER) << 4);
1039     vnc_write_u8(vs, VNC_TIGHT_FILTER_GRADIENT);
1040 
1041     buffer_reserve(&vs->tight.gradient, w * 3 * sizeof (int));
1042 
1043     if (vs->tight.pixel24) {
1044         tight_filter_gradient24(vs, vs->tight.tight.buffer, w, h);
1045         bytes = 3;
1046     } else if (vs->clientds.pf.bytes_per_pixel == 4) {
1047         tight_filter_gradient32(vs, (uint32_t *)vs->tight.tight.buffer, w, h);
1048         bytes = 4;
1049     } else {
1050         tight_filter_gradient16(vs, (uint16_t *)vs->tight.tight.buffer, w, h);
1051         bytes = 2;
1052     }
1053 
1054     buffer_reset(&vs->tight.gradient);
1055 
1056     bytes = w * h * bytes;
1057     vs->tight.tight.offset = bytes;
1058 
1059     bytes = tight_compress_data(vs, stream, bytes,
1060                                 level, Z_FILTERED);
1061     return (bytes >= 0);
1062 }
1063 
send_palette_rect(VncState * vs,int x,int y,int w,int h,VncPalette * palette)1064 static int send_palette_rect(VncState *vs, int x, int y,
1065                              int w, int h, VncPalette *palette)
1066 {
1067     int stream = 2;
1068     int level = tight_conf[vs->tight.compression].idx_zlib_level;
1069     int colors;
1070     ssize_t bytes;
1071 
1072 #ifdef CONFIG_VNC_PNG
1073     if (tight_can_send_png_rect(vs, w, h)) {
1074         return send_png_rect(vs, x, y, w, h, palette);
1075     }
1076 #endif
1077 
1078     colors = palette_size(palette);
1079 
1080     vnc_write_u8(vs, (stream | VNC_TIGHT_EXPLICIT_FILTER) << 4);
1081     vnc_write_u8(vs, VNC_TIGHT_FILTER_PALETTE);
1082     vnc_write_u8(vs, colors - 1);
1083 
1084     switch(vs->clientds.pf.bytes_per_pixel) {
1085     case 4:
1086     {
1087         size_t old_offset, offset;
1088         uint32_t header[palette_size(palette)];
1089         struct palette_cb_priv priv = { vs, (uint8_t *)header };
1090 
1091         old_offset = vs->output.offset;
1092         palette_iter(palette, write_palette, &priv);
1093         vnc_write(vs, header, sizeof(header));
1094 
1095         if (vs->tight.pixel24) {
1096             tight_pack24(vs, vs->output.buffer + old_offset, colors, &offset);
1097             vs->output.offset = old_offset + offset;
1098         }
1099 
1100         tight_encode_indexed_rect32(vs->tight.tight.buffer, w * h, palette);
1101         break;
1102     }
1103     case 2:
1104     {
1105         uint16_t header[palette_size(palette)];
1106         struct palette_cb_priv priv = { vs, (uint8_t *)header };
1107 
1108         palette_iter(palette, write_palette, &priv);
1109         vnc_write(vs, header, sizeof(header));
1110         tight_encode_indexed_rect16(vs->tight.tight.buffer, w * h, palette);
1111         break;
1112     }
1113     default:
1114         return -1; /* No palette for 8bits colors */
1115         break;
1116     }
1117     bytes = w * h;
1118     vs->tight.tight.offset = bytes;
1119 
1120     bytes = tight_compress_data(vs, stream, bytes,
1121                                 level, Z_DEFAULT_STRATEGY);
1122     return (bytes >= 0);
1123 }
1124 
1125 #if defined(CONFIG_VNC_JPEG) || defined(CONFIG_VNC_PNG)
rgb_prepare_row24(VncState * vs,uint8_t * dst,int x,int y,int count)1126 static void rgb_prepare_row24(VncState *vs, uint8_t *dst, int x, int y,
1127                               int count)
1128 {
1129     VncDisplay *vd = vs->vd;
1130     uint32_t *fbptr;
1131     uint32_t pix;
1132 
1133     fbptr = (uint32_t *)(vd->server->data + y * ds_get_linesize(vs->ds) +
1134                          x * ds_get_bytes_per_pixel(vs->ds));
1135 
1136     while (count--) {
1137         pix = *fbptr++;
1138         *dst++ = (uint8_t)(pix >> vs->ds->surface->pf.rshift);
1139         *dst++ = (uint8_t)(pix >> vs->ds->surface->pf.gshift);
1140         *dst++ = (uint8_t)(pix >> vs->ds->surface->pf.bshift);
1141     }
1142 }
1143 
1144 #define DEFINE_RGB_GET_ROW_FUNCTION(bpp)                                \
1145                                                                         \
1146     static void                                                         \
1147     rgb_prepare_row##bpp(VncState *vs, uint8_t *dst,                    \
1148                          int x, int y, int count)                       \
1149     {                                                                   \
1150         VncDisplay *vd = vs->vd;                                        \
1151         uint##bpp##_t *fbptr;                                           \
1152         uint##bpp##_t pix;                                              \
1153         int r, g, b;                                                    \
1154                                                                         \
1155         fbptr = (uint##bpp##_t *)                                       \
1156             (vd->server->data + y * ds_get_linesize(vs->ds) +           \
1157              x * ds_get_bytes_per_pixel(vs->ds));                       \
1158                                                                         \
1159         while (count--) {                                               \
1160             pix = *fbptr++;                                             \
1161                                                                         \
1162             r = (int)((pix >> vs->ds->surface->pf.rshift)               \
1163                       & vs->ds->surface->pf.rmax);                      \
1164             g = (int)((pix >> vs->ds->surface->pf.gshift)               \
1165                       & vs->ds->surface->pf.gmax);                      \
1166             b = (int)((pix >> vs->ds->surface->pf.bshift)               \
1167                       & vs->ds->surface->pf.bmax);                      \
1168                                                                         \
1169             *dst++ = (uint8_t)((r * 255 + vs->ds->surface->pf.rmax / 2) \
1170                                / vs->ds->surface->pf.rmax);             \
1171             *dst++ = (uint8_t)((g * 255 + vs->ds->surface->pf.gmax / 2) \
1172                                / vs->ds->surface->pf.gmax);             \
1173             *dst++ = (uint8_t)((b * 255 + vs->ds->surface->pf.bmax / 2) \
1174                                / vs->ds->surface->pf.bmax);             \
1175         }                                                               \
1176     }
1177 
1178 DEFINE_RGB_GET_ROW_FUNCTION(16)
1179 DEFINE_RGB_GET_ROW_FUNCTION(32)
1180 
rgb_prepare_row(VncState * vs,uint8_t * dst,int x,int y,int count)1181 static void rgb_prepare_row(VncState *vs, uint8_t *dst, int x, int y,
1182                             int count)
1183 {
1184     if (ds_get_bytes_per_pixel(vs->ds) == 4) {
1185         if (vs->ds->surface->pf.rmax == 0xFF &&
1186             vs->ds->surface->pf.gmax == 0xFF &&
1187             vs->ds->surface->pf.bmax == 0xFF) {
1188             rgb_prepare_row24(vs, dst, x, y, count);
1189         } else {
1190             rgb_prepare_row32(vs, dst, x, y, count);
1191         }
1192     } else {
1193         rgb_prepare_row16(vs, dst, x, y, count);
1194     }
1195 }
1196 #endif /* CONFIG_VNC_JPEG or CONFIG_VNC_PNG */
1197 
1198 /*
1199  * JPEG compression stuff.
1200  */
1201 #ifdef CONFIG_VNC_JPEG
1202 /*
1203  * Destination manager implementation for JPEG library.
1204  */
1205 
1206 /* This is called once per encoding */
jpeg_init_destination(j_compress_ptr cinfo)1207 static void jpeg_init_destination(j_compress_ptr cinfo)
1208 {
1209     VncState *vs = cinfo->client_data;
1210     Buffer *buffer = &vs->tight.jpeg;
1211 
1212     cinfo->dest->next_output_byte = (JOCTET *)buffer->buffer + buffer->offset;
1213     cinfo->dest->free_in_buffer = (size_t)(buffer->capacity - buffer->offset);
1214 }
1215 
1216 /* This is called when we ran out of buffer (shouldn't happen!) */
jpeg_empty_output_buffer(j_compress_ptr cinfo)1217 static boolean jpeg_empty_output_buffer(j_compress_ptr cinfo)
1218 {
1219     VncState *vs = cinfo->client_data;
1220     Buffer *buffer = &vs->tight.jpeg;
1221 
1222     buffer->offset = buffer->capacity;
1223     buffer_reserve(buffer, 2048);
1224     jpeg_init_destination(cinfo);
1225     return TRUE;
1226 }
1227 
1228 /* This is called when we are done processing data */
jpeg_term_destination(j_compress_ptr cinfo)1229 static void jpeg_term_destination(j_compress_ptr cinfo)
1230 {
1231     VncState *vs = cinfo->client_data;
1232     Buffer *buffer = &vs->tight.jpeg;
1233 
1234     buffer->offset = buffer->capacity - cinfo->dest->free_in_buffer;
1235 }
1236 
send_jpeg_rect(VncState * vs,int x,int y,int w,int h,int quality)1237 static int send_jpeg_rect(VncState *vs, int x, int y, int w, int h, int quality)
1238 {
1239     struct jpeg_compress_struct cinfo;
1240     struct jpeg_error_mgr jerr;
1241     struct jpeg_destination_mgr manager;
1242     JSAMPROW row[1];
1243     uint8_t *buf;
1244     int dy;
1245 
1246     if (ds_get_bytes_per_pixel(vs->ds) == 1)
1247         return send_full_color_rect(vs, x, y, w, h);
1248 
1249     buffer_reserve(&vs->tight.jpeg, 2048);
1250 
1251     cinfo.err = jpeg_std_error(&jerr);
1252     jpeg_create_compress(&cinfo);
1253 
1254     cinfo.client_data = vs;
1255     cinfo.image_width = w;
1256     cinfo.image_height = h;
1257     cinfo.input_components = 3;
1258     cinfo.in_color_space = JCS_RGB;
1259 
1260     jpeg_set_defaults(&cinfo);
1261     jpeg_set_quality(&cinfo, quality, true);
1262 
1263     manager.init_destination = jpeg_init_destination;
1264     manager.empty_output_buffer = jpeg_empty_output_buffer;
1265     manager.term_destination = jpeg_term_destination;
1266     cinfo.dest = &manager;
1267 
1268     jpeg_start_compress(&cinfo, true);
1269 
1270     buf = qemu_malloc(w * 3);
1271     row[0] = buf;
1272     for (dy = 0; dy < h; dy++) {
1273         rgb_prepare_row(vs, buf, x, y + dy, w);
1274         jpeg_write_scanlines(&cinfo, row, 1);
1275     }
1276     qemu_free(buf);
1277 
1278     jpeg_finish_compress(&cinfo);
1279     jpeg_destroy_compress(&cinfo);
1280 
1281     vnc_write_u8(vs, VNC_TIGHT_JPEG << 4);
1282 
1283     tight_send_compact_size(vs, vs->tight.jpeg.offset);
1284     vnc_write(vs, vs->tight.jpeg.buffer, vs->tight.jpeg.offset);
1285     buffer_reset(&vs->tight.jpeg);
1286 
1287     return 1;
1288 }
1289 #endif /* CONFIG_VNC_JPEG */
1290 
1291 /*
1292  * PNG compression stuff.
1293  */
1294 #ifdef CONFIG_VNC_PNG
write_png_palette(int idx,uint32_t pix,void * opaque)1295 static void write_png_palette(int idx, uint32_t pix, void *opaque)
1296 {
1297     struct palette_cb_priv *priv = opaque;
1298     VncState *vs = priv->vs;
1299     png_colorp color = &priv->png_palette[idx];
1300 
1301     if (vs->tight.pixel24)
1302     {
1303         color->red = (pix >> vs->clientds.pf.rshift) & vs->clientds.pf.rmax;
1304         color->green = (pix >> vs->clientds.pf.gshift) & vs->clientds.pf.gmax;
1305         color->blue = (pix >> vs->clientds.pf.bshift) & vs->clientds.pf.bmax;
1306     }
1307     else
1308     {
1309         int red, green, blue;
1310 
1311         red = (pix >> vs->clientds.pf.rshift) & vs->clientds.pf.rmax;
1312         green = (pix >> vs->clientds.pf.gshift) & vs->clientds.pf.gmax;
1313         blue = (pix >> vs->clientds.pf.bshift) & vs->clientds.pf.bmax;
1314         color->red = ((red * 255 + vs->clientds.pf.rmax / 2) /
1315                       vs->clientds.pf.rmax);
1316         color->green = ((green * 255 + vs->clientds.pf.gmax / 2) /
1317                         vs->clientds.pf.gmax);
1318         color->blue = ((blue * 255 + vs->clientds.pf.bmax / 2) /
1319                        vs->clientds.pf.bmax);
1320     }
1321 }
1322 
png_write_data(png_structp png_ptr,png_bytep data,png_size_t length)1323 static void png_write_data(png_structp png_ptr, png_bytep data,
1324                            png_size_t length)
1325 {
1326     VncState *vs = png_get_io_ptr(png_ptr);
1327 
1328     buffer_reserve(&vs->tight.png, vs->tight.png.offset + length);
1329     memcpy(vs->tight.png.buffer + vs->tight.png.offset, data, length);
1330 
1331     vs->tight.png.offset += length;
1332 }
1333 
png_flush_data(png_structp png_ptr)1334 static void png_flush_data(png_structp png_ptr)
1335 {
1336 }
1337 
vnc_png_malloc(png_structp png_ptr,png_size_t size)1338 static void *vnc_png_malloc(png_structp png_ptr, png_size_t size)
1339 {
1340     return qemu_malloc(size);
1341 }
1342 
vnc_png_free(png_structp png_ptr,png_voidp ptr)1343 static void vnc_png_free(png_structp png_ptr, png_voidp ptr)
1344 {
1345     qemu_free(ptr);
1346 }
1347 
send_png_rect(VncState * vs,int x,int y,int w,int h,VncPalette * palette)1348 static int send_png_rect(VncState *vs, int x, int y, int w, int h,
1349                          VncPalette *palette)
1350 {
1351     png_byte color_type;
1352     png_structp png_ptr;
1353     png_infop info_ptr;
1354     png_colorp png_palette = NULL;
1355     int level = tight_png_conf[vs->tight.compression].png_zlib_level;
1356     int filters = tight_png_conf[vs->tight.compression].png_filters;
1357     uint8_t *buf;
1358     int dy;
1359 
1360     png_ptr = png_create_write_struct_2(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL,
1361                                         NULL, vnc_png_malloc, vnc_png_free);
1362 
1363     if (png_ptr == NULL)
1364         return -1;
1365 
1366     info_ptr = png_create_info_struct(png_ptr);
1367 
1368     if (info_ptr == NULL) {
1369         png_destroy_write_struct(&png_ptr, NULL);
1370         return -1;
1371     }
1372 
1373     png_set_write_fn(png_ptr, (void *) vs, png_write_data, png_flush_data);
1374     png_set_compression_level(png_ptr, level);
1375     png_set_filter(png_ptr, PNG_FILTER_TYPE_DEFAULT, filters);
1376 
1377     if (palette) {
1378         color_type = PNG_COLOR_TYPE_PALETTE;
1379     } else {
1380         color_type = PNG_COLOR_TYPE_RGB;
1381     }
1382 
1383     png_set_IHDR(png_ptr, info_ptr, w, h,
1384                  8, color_type, PNG_INTERLACE_NONE,
1385                  PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
1386 
1387     if (color_type == PNG_COLOR_TYPE_PALETTE) {
1388         struct palette_cb_priv priv;
1389 
1390         png_palette = png_malloc(png_ptr, sizeof(*png_palette) *
1391                                  palette_size(palette));
1392 
1393         priv.vs = vs;
1394         priv.png_palette = png_palette;
1395         palette_iter(palette, write_png_palette, &priv);
1396 
1397         png_set_PLTE(png_ptr, info_ptr, png_palette, palette_size(palette));
1398 
1399         if (vs->clientds.pf.bytes_per_pixel == 4) {
1400             tight_encode_indexed_rect32(vs->tight.tight.buffer, w * h, palette);
1401         } else {
1402             tight_encode_indexed_rect16(vs->tight.tight.buffer, w * h, palette);
1403         }
1404     }
1405 
1406     png_write_info(png_ptr, info_ptr);
1407 
1408     buffer_reserve(&vs->tight.png, 2048);
1409     buf = qemu_malloc(w * 3);
1410     for (dy = 0; dy < h; dy++)
1411     {
1412         if (color_type == PNG_COLOR_TYPE_PALETTE) {
1413             memcpy(buf, vs->tight.tight.buffer + (dy * w), w);
1414         } else {
1415             rgb_prepare_row(vs, buf, x, y + dy, w);
1416         }
1417         png_write_row(png_ptr, buf);
1418     }
1419     qemu_free(buf);
1420 
1421     png_write_end(png_ptr, NULL);
1422 
1423     if (color_type == PNG_COLOR_TYPE_PALETTE) {
1424         png_free(png_ptr, png_palette);
1425     }
1426 
1427     png_destroy_write_struct(&png_ptr, &info_ptr);
1428 
1429     vnc_write_u8(vs, VNC_TIGHT_PNG << 4);
1430 
1431     tight_send_compact_size(vs, vs->tight.png.offset);
1432     vnc_write(vs, vs->tight.png.buffer, vs->tight.png.offset);
1433     buffer_reset(&vs->tight.png);
1434     return 1;
1435 }
1436 #endif /* CONFIG_VNC_PNG */
1437 
vnc_tight_start(VncState * vs)1438 static void vnc_tight_start(VncState *vs)
1439 {
1440     buffer_reset(&vs->tight.tight);
1441 
1442     // make the output buffer be the zlib buffer, so we can compress it later
1443     vs->tight.tmp = vs->output;
1444     vs->output = vs->tight.tight;
1445 }
1446 
vnc_tight_stop(VncState * vs)1447 static void vnc_tight_stop(VncState *vs)
1448 {
1449     // switch back to normal output/zlib buffers
1450     vs->tight.tight = vs->output;
1451     vs->output = vs->tight.tmp;
1452 }
1453 
send_sub_rect_nojpeg(VncState * vs,int x,int y,int w,int h,int bg,int fg,int colors,VncPalette * palette)1454 static int send_sub_rect_nojpeg(VncState *vs, int x, int y, int w, int h,
1455                                 int bg, int fg, int colors, VncPalette *palette)
1456 {
1457     int ret;
1458 
1459     if (colors == 0) {
1460         if (tight_detect_smooth_image(vs, w, h)) {
1461             ret = send_gradient_rect(vs, x, y, w, h);
1462         } else {
1463             ret = send_full_color_rect(vs, x, y, w, h);
1464         }
1465     } else if (colors == 1) {
1466         ret = send_solid_rect(vs);
1467     } else if (colors == 2) {
1468         ret = send_mono_rect(vs, x, y, w, h, bg, fg);
1469     } else if (colors <= 256) {
1470         ret = send_palette_rect(vs, x, y, w, h, palette);
1471     } else {
1472         ret = 0;
1473     }
1474     return ret;
1475 }
1476 
1477 #ifdef CONFIG_VNC_JPEG
send_sub_rect_jpeg(VncState * vs,int x,int y,int w,int h,int bg,int fg,int colors,VncPalette * palette)1478 static int send_sub_rect_jpeg(VncState *vs, int x, int y, int w, int h,
1479                               int bg, int fg, int colors,
1480                               VncPalette *palette)
1481 {
1482     int ret;
1483 
1484     if (colors == 0) {
1485         if (tight_detect_smooth_image(vs, w, h)) {
1486             int quality = tight_conf[vs->tight.quality].jpeg_quality;
1487 
1488             ret = send_jpeg_rect(vs, x, y, w, h, quality);
1489         } else {
1490             ret = send_full_color_rect(vs, x, y, w, h);
1491         }
1492     } else if (colors == 1) {
1493         ret = send_solid_rect(vs);
1494     } else if (colors == 2) {
1495         ret = send_mono_rect(vs, x, y, w, h, bg, fg);
1496     } else if (colors <= 256) {
1497         if (colors > 96 &&
1498             tight_detect_smooth_image(vs, w, h)) {
1499             int quality = tight_conf[vs->tight.quality].jpeg_quality;
1500 
1501             ret = send_jpeg_rect(vs, x, y, w, h, quality);
1502         } else {
1503             ret = send_palette_rect(vs, x, y, w, h, palette);
1504         }
1505     } else {
1506         ret = 0;
1507     }
1508     return ret;
1509 }
1510 #endif
1511 
send_sub_rect(VncState * vs,int x,int y,int w,int h)1512 static int send_sub_rect(VncState *vs, int x, int y, int w, int h)
1513 {
1514     VncPalette *palette = NULL;
1515     uint32_t bg = 0, fg = 0;
1516     int colors;
1517     int ret = 0;
1518 
1519     vnc_framebuffer_update(vs, x, y, w, h, vs->tight.type);
1520 
1521     vnc_tight_start(vs);
1522     vnc_raw_send_framebuffer_update(vs, x, y, w, h);
1523     vnc_tight_stop(vs);
1524 
1525     colors = tight_fill_palette(vs, x, y, w * h, &fg, &bg, &palette);
1526 
1527 #ifdef CONFIG_VNC_JPEG
1528     if (vs->tight.quality != (uint8_t)-1) {
1529         ret = send_sub_rect_jpeg(vs, x, y, w, h, bg, fg, colors, palette);
1530     } else {
1531         ret = send_sub_rect_nojpeg(vs, x, y, w, h, bg, fg, colors, palette);
1532     }
1533 #else
1534     ret = send_sub_rect_nojpeg(vs, x, y, w, h, bg, fg, colors, palette);
1535 #endif
1536 
1537     palette_destroy(palette);
1538     return ret;
1539 }
1540 
send_sub_rect_solid(VncState * vs,int x,int y,int w,int h)1541 static int send_sub_rect_solid(VncState *vs, int x, int y, int w, int h)
1542 {
1543     vnc_framebuffer_update(vs, x, y, w, h, vs->tight.type);
1544 
1545     vnc_tight_start(vs);
1546     vnc_raw_send_framebuffer_update(vs, x, y, w, h);
1547     vnc_tight_stop(vs);
1548 
1549     return send_solid_rect(vs);
1550 }
1551 
send_rect_simple(VncState * vs,int x,int y,int w,int h)1552 static int send_rect_simple(VncState *vs, int x, int y, int w, int h)
1553 {
1554     int max_size, max_width;
1555     int max_sub_width, max_sub_height;
1556     int dx, dy;
1557     int rw, rh;
1558     int n = 0;
1559 
1560     max_size = tight_conf[vs->tight.compression].max_rect_size;
1561     max_width = tight_conf[vs->tight.compression].max_rect_width;
1562 
1563     if (w > max_width || w * h > max_size) {
1564         max_sub_width = (w > max_width) ? max_width : w;
1565         max_sub_height = max_size / max_sub_width;
1566 
1567         for (dy = 0; dy < h; dy += max_sub_height) {
1568             for (dx = 0; dx < w; dx += max_width) {
1569                 rw = MIN(max_sub_width, w - dx);
1570                 rh = MIN(max_sub_height, h - dy);
1571                 n += send_sub_rect(vs, x+dx, y+dy, rw, rh);
1572             }
1573         }
1574     } else {
1575         n += send_sub_rect(vs, x, y, w, h);
1576     }
1577 
1578     return n;
1579 }
1580 
find_large_solid_color_rect(VncState * vs,int x,int y,int w,int h,int max_rows)1581 static int find_large_solid_color_rect(VncState *vs, int x, int y,
1582                                        int w, int h, int max_rows)
1583 {
1584     int dx, dy, dw, dh;
1585     int n = 0;
1586 
1587     /* Try to find large solid-color areas and send them separately. */
1588 
1589     for (dy = y; dy < y + h; dy += VNC_TIGHT_MAX_SPLIT_TILE_SIZE) {
1590 
1591         /* If a rectangle becomes too large, send its upper part now. */
1592 
1593         if (dy - y >= max_rows) {
1594             n += send_rect_simple(vs, x, y, w, max_rows);
1595             y += max_rows;
1596             h -= max_rows;
1597         }
1598 
1599         dh = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, (y + h - dy));
1600 
1601         for (dx = x; dx < x + w; dx += VNC_TIGHT_MAX_SPLIT_TILE_SIZE) {
1602             uint32_t color_value;
1603             int x_best, y_best, w_best, h_best;
1604 
1605             dw = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, (x + w - dx));
1606 
1607             if (!check_solid_tile(vs, dx, dy, dw, dh, &color_value, false)) {
1608                 continue ;
1609             }
1610 
1611             /* Get dimensions of solid-color area. */
1612 
1613             find_best_solid_area(vs, dx, dy, w - (dx - x), h - (dy - y),
1614                                  color_value, &w_best, &h_best);
1615 
1616             /* Make sure a solid rectangle is large enough
1617                (or the whole rectangle is of the same color). */
1618 
1619             if (w_best * h_best != w * h &&
1620                 w_best * h_best < VNC_TIGHT_MIN_SOLID_SUBRECT_SIZE) {
1621                 continue;
1622             }
1623 
1624             /* Try to extend solid rectangle to maximum size. */
1625 
1626             x_best = dx; y_best = dy;
1627             extend_solid_area(vs, x, y, w, h, color_value,
1628                               &x_best, &y_best, &w_best, &h_best);
1629 
1630             /* Send rectangles at top and left to solid-color area. */
1631 
1632             if (y_best != y) {
1633                 n += send_rect_simple(vs, x, y, w, y_best-y);
1634             }
1635             if (x_best != x) {
1636                 n += tight_send_framebuffer_update(vs, x, y_best,
1637                                                    x_best-x, h_best);
1638             }
1639 
1640             /* Send solid-color rectangle. */
1641             n += send_sub_rect_solid(vs, x_best, y_best, w_best, h_best);
1642 
1643             /* Send remaining rectangles (at right and bottom). */
1644 
1645             if (x_best + w_best != x + w) {
1646                 n += tight_send_framebuffer_update(vs, x_best+w_best,
1647                                                    y_best,
1648                                                    w-(x_best-x)-w_best,
1649                                                    h_best);
1650             }
1651             if (y_best + h_best != y + h) {
1652                 n += tight_send_framebuffer_update(vs, x, y_best+h_best,
1653                                                    w, h-(y_best-y)-h_best);
1654             }
1655 
1656             /* Return after all recursive calls are done. */
1657             return n;
1658         }
1659     }
1660     return n + send_rect_simple(vs, x, y, w, h);
1661 }
1662 
tight_send_framebuffer_update(VncState * vs,int x,int y,int w,int h)1663 static int tight_send_framebuffer_update(VncState *vs, int x, int y,
1664                                          int w, int h)
1665 {
1666     int max_rows;
1667 
1668     if (vs->clientds.pf.bytes_per_pixel == 4 && vs->clientds.pf.rmax == 0xFF &&
1669         vs->clientds.pf.bmax == 0xFF && vs->clientds.pf.gmax == 0xFF) {
1670         vs->tight.pixel24 = true;
1671     } else {
1672         vs->tight.pixel24 = false;
1673     }
1674 
1675     if (w * h < VNC_TIGHT_MIN_SPLIT_RECT_SIZE)
1676         return send_rect_simple(vs, x, y, w, h);
1677 
1678     /* Calculate maximum number of rows in one non-solid rectangle. */
1679 
1680     max_rows = tight_conf[vs->tight.compression].max_rect_size;
1681     max_rows /= MIN(tight_conf[vs->tight.compression].max_rect_width, w);
1682 
1683     return find_large_solid_color_rect(vs, x, y, w, h, max_rows);
1684 }
1685 
vnc_tight_send_framebuffer_update(VncState * vs,int x,int y,int w,int h)1686 int vnc_tight_send_framebuffer_update(VncState *vs, int x, int y,
1687                                       int w, int h)
1688 {
1689     vs->tight.type = VNC_ENCODING_TIGHT;
1690     return tight_send_framebuffer_update(vs, x, y, w, h);
1691 }
1692 
vnc_tight_png_send_framebuffer_update(VncState * vs,int x,int y,int w,int h)1693 int vnc_tight_png_send_framebuffer_update(VncState *vs, int x, int y,
1694                                           int w, int h)
1695 {
1696     vs->tight.type = VNC_ENCODING_TIGHT_PNG;
1697     return tight_send_framebuffer_update(vs, x, y, w, h);
1698 }
1699 
vnc_tight_clear(VncState * vs)1700 void vnc_tight_clear(VncState *vs)
1701 {
1702     int i;
1703     for (i=0; i<ARRAY_SIZE(vs->tight.stream); i++) {
1704         if (vs->tight.stream[i].opaque) {
1705             deflateEnd(&vs->tight.stream[i]);
1706         }
1707     }
1708 
1709     buffer_free(&vs->tight.tight);
1710     buffer_free(&vs->tight.zlib);
1711     buffer_free(&vs->tight.gradient);
1712 #ifdef CONFIG_VNC_JPEG
1713     buffer_free(&vs->tight.jpeg);
1714 #endif
1715 #ifdef CONFIG_VNC_PNG
1716     buffer_free(&vs->tight.png);
1717 #endif
1718 }
1719