summaryrefslogtreecommitdiffstats
path: root/ui/vnc-enc-zrle.c
blob: 5489870e700d6d8b246de8d0bc5595d3c955e67d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
/*
 * QEMU VNC display driver: Zlib Run-length Encoding (ZRLE)
 *
 * From libvncserver/libvncserver/zrle.c
 * Copyright (C) 2002 RealVNC Ltd.  All Rights Reserved.
 * Copyright (C) 2003 Sun Microsystems, Inc.
 *
 * Copyright (C) 2010 Corentin Chary <corentin.chary@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "qemu/osdep.h"
#include "vnc.h"
#include "vnc-enc-zrle.h"

static const int bits_per_packed_pixel[] = {
  0, 1, 2, 2, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4
};


static void vnc_zrle_start(VncState *vs)
{
    buffer_reset(&vs->zrle.zrle);

    /* make the output buffer be the zlib buffer, so we can compress it later */
    vs->zrle.tmp = vs->output;
    vs->output = vs->zrle.zrle;
}

static void vnc_zrle_stop(VncState *vs)
{
    /* switch back to normal output/zlib buffers */
    vs->zrle.zrle = vs->output;
    vs->output = vs->zrle.tmp;
}

static void *zrle_convert_fb(VncState *vs, int x, int y, int w, int h,
                             int bpp)
{
    Buffer tmp;

    buffer_reset(&vs->zrle.fb);
    buffer_reserve(&vs->zrle.fb, w * h * bpp + bpp);

    tmp = vs->output;
    vs->output = vs->zrle.fb;

    vnc_raw_send_framebuffer_update(vs, x, y, w, h);

    vs->zrle.fb = vs->output;
    vs->output = tmp;
    return vs->zrle.fb.buffer;
}

static int zrle_compress_data(VncState *vs, int level)
{
    z_streamp zstream = &vs->zrle.stream;

    buffer_reset(&vs->zrle.zlib);

    if (zstream->opaque != vs) {
        int err;

        zstream->zalloc = vnc_zlib_zalloc;
        zstream->zfree = vnc_zlib_zfree;

        err = deflateInit2(zstream, level, Z_DEFLATED, MAX_WBITS,
                           MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY);

        if (err != Z_OK) {
            fprintf(stderr, "VNC: error initializing zlib\n");
            return -1;
        }

        zstream->opaque = vs;
    }

    /* reserve memory in output buffer */
    buffer_reserve(&vs->zrle.zlib, vs->zrle.zrle.offset + 64);

    /* set pointers */
    zstream->next_in = vs->zrle.zrle.buffer;
    zstream->avail_in = vs->zrle.zrle.offset;
    zstream->next_out = vs->zrle.zlib.buffer + vs->zrle.zlib.offset;
    zstream->avail_out = vs->zrle.zlib.capacity - vs->zrle.zlib.offset;
    zstream->data_type = Z_BINARY;

    /* start encoding */
    if (deflate(zstream, Z_SYNC_FLUSH) != Z_OK) {
        fprintf(stderr, "VNC: error during zrle compression\n");
        return -1;
    }

    vs->zrle.zlib.offset = vs->zrle.zlib.capacity - zstream->avail_out;
    return vs->zrle.zlib.offset;
}

/* Try to work out whether to use RLE and/or a palette.  We do this by
 * estimating the number of bytes which will be generated and picking the
 * method which results in the fewest bytes.  Of course this may not result
 * in the fewest bytes after compression... */
static void zrle_choose_palette_rle(VncState *vs, int w, int h,
                                    VncPalette *palette, int bpp_out,
                                    int runs, int single_pixels,
                                    int zywrle_level,
                                    bool *use_rle, bool *use_palette)
{
    size_t estimated_bytes;
    size_t plain_rle_bytes;

    *use_palette = *use_rle = false;

    estimated_bytes = w * h * (bpp_out / 8); /* start assuming raw */

    if (bpp_out != 8) {
        if (zywrle_level > 0 && !(zywrle_level & 0x80))
            estimated_bytes >>= zywrle_level;
    }

    plain_rle_bytes = ((bpp_out / 8) + 1) * (runs + single_pixels);

    if (plain_rle_bytes < estimated_bytes) {
        *use_rle = true;
        estimated_bytes = plain_rle_bytes;
    }

    if (palette_size(palette) < 128) {
        int palette_rle_bytes;

        palette_rle_bytes = (bpp_out / 8) * palette_size(palette);
        palette_rle_bytes += 2 * runs + single_pixels;

        if (palette_rle_bytes < estimated_bytes) {
            *use_rle = true;
            *use_palette = true;
            estimated_bytes = palette_rle_bytes;
        }

        if (palette_size(palette) < 17) {
            int packed_bytes;

            packed_bytes = (bpp_out / 8) * palette_size(palette);
            packed_bytes += w * h *
                bits_per_packed_pixel[palette_size(palette)-1] / 8;

            if (packed_bytes < estimated_bytes) {
                *use_rle = false;
                *use_palette = true;
                estimated_bytes = packed_bytes;
            }
        }
    }
}

static void zrle_write_u32(VncState *vs, uint32_t value)
{
    vnc_write(vs, (uint8_t *)&value, 4);
}

static void zrle_write_u24a(VncState *vs, uint32_t value)
{
    vnc_write(vs, (uint8_t *)&value, 3);
}

static void zrle_write_u24b(VncState *vs, uint32_t value)
{
    vnc_write(vs, ((uint8_t *)&value) + 1, 3);
}

static void zrle_write_u16(VncState *vs, uint16_t value)
{
    vnc_write(vs, (uint8_t *)&value, 2);
}

static void zrle_write_u8(VncState *vs, uint8_t value)
{
    vnc_write_u8(vs, value);
}

#define ENDIAN_LITTLE 0
#define ENDIAN_BIG    1
#define ENDIAN_NO     2

#define ZRLE_BPP 8
#define ZYWRLE_ENDIAN ENDIAN_NO
#include "vnc-enc-zrle-template.c"
#undef ZRLE_BPP

#define ZRLE_BPP 15
#undef ZYWRLE_ENDIAN
#define ZYWRLE_ENDIAN ENDIAN_LITTLE
#include "vnc-enc-zrle-template.c"

#undef ZYWRLE_ENDIAN
#define ZYWRLE_ENDIAN ENDIAN_BIG
#include "vnc-enc-zrle-template.c"

#undef ZRLE_BPP
#define ZRLE_BPP 16
#undef ZYWRLE_ENDIAN
#define ZYWRLE_ENDIAN ENDIAN_LITTLE
#include "vnc-enc-zrle-template.c"

#undef ZYWRLE_ENDIAN
#define ZYWRLE_ENDIAN ENDIAN_BIG
#include "vnc-enc-zrle-template.c"

#undef ZRLE_BPP
#define ZRLE_BPP 32
#undef ZYWRLE_ENDIAN
#define ZYWRLE_ENDIAN ENDIAN_LITTLE
#include "vnc-enc-zrle-template.c"

#undef ZYWRLE_ENDIAN
#define ZYWRLE_ENDIAN ENDIAN_BIG
#include "vnc-enc-zrle-template.c"

#define ZRLE_COMPACT_PIXEL 24a
#undef ZYWRLE_ENDIAN
#define ZYWRLE_ENDIAN ENDIAN_LITTLE
#include "vnc-enc-zrle-template.c"

#undef ZYWRLE_ENDIAN
#define ZYWRLE_ENDIAN ENDIAN_BIG
#include "vnc-enc-zrle-template.c"

#undef ZRLE_COMPACT_PIXEL
#define ZRLE_COMPACT_PIXEL 24b
#undef ZYWRLE_ENDIAN
#define ZYWRLE_ENDIAN ENDIAN_LITTLE
#include "vnc-enc-zrle-template.c"

#undef ZYWRLE_ENDIAN
#define ZYWRLE_ENDIAN ENDIAN_BIG
#include "vnc-enc-zrle-template.c"
#undef ZRLE_COMPACT_PIXEL
#undef ZRLE_BPP

static int zrle_send_framebuffer_update(VncState *vs, int x, int y,
                                        int w, int h)
{
    bool be = vs->client_be;
    size_t bytes;
    int zywrle_level;

    if (vs->zrle.type == VNC_ENCODING_ZYWRLE) {
        if (!vs->vd->lossy || vs->tight.quality == (uint8_t)-1
            || vs->tight.quality == 9) {
            zywrle_level = 0;
            vs->zrle.type = VNC_ENCODING_ZRLE;
        } else if (vs->tight.quality < 3) {
            zywrle_level = 3;
        } else if (vs->tight.quality < 6) {
            zywrle_level = 2;
        } else {
            zywrle_level = 1;
        }
    } else {
        zywrle_level = 0;
    }

    vnc_zrle_start(vs);

    switch (vs->client_pf.bytes_per_pixel) {
    case 1:
        zrle_encode_8ne(vs, x, y, w, h, zywrle_level);
        break;

    case 2:
        if (vs->client_pf.gmax > 0x1F) {
            if (be) {
                zrle_encode_16be(vs, x, y, w, h, zywrle_level);
            } else {
                zrle_encode_16le(vs, x, y, w, h, zywrle_level);
            }
        } else {
            if (be) {
                zrle_encode_15be(vs, x, y, w, h, zywrle_level);
            } else {
                zrle_encode_15le(vs, x, y, w, h, zywrle_level);
            }
        }
        break;

    case 4:
    {
        bool fits_in_ls3bytes;
        bool fits_in_ms3bytes;

        fits_in_ls3bytes =
            ((vs->client_pf.rmax << vs->client_pf.rshift) < (1 << 24) &&
             (vs->client_pf.gmax << vs->client_pf.gshift) < (1 << 24) &&
             (vs->client_pf.bmax << vs->client_pf.bshift) < (1 << 24));

        fits_in_ms3bytes = (vs->client_pf.rshift > 7 &&
                            vs->client_pf.gshift > 7 &&
                            vs->client_pf.bshift > 7);

        if ((fits_in_ls3bytes && !be) || (fits_in_ms3bytes && be)) {
            if (be) {
                zrle_encode_24abe(vs, x, y, w, h, zywrle_level);
            } else {
                zrle_encode_24ale(vs, x, y, w, h, zywrle_level);
          }
        } else if ((fits_in_ls3bytes && be) || (fits_in_ms3bytes && !be)) {
            if (be) {
                zrle_encode_24bbe(vs, x, y, w, h, zywrle_level);
            } else {
                zrle_encode_24ble(vs, x, y, w, h, zywrle_level);
            }
        } else {
            if (be) {
                zrle_encode_32be(vs, x, y, w, h, zywrle_level);
            } else {
                zrle_encode_32le(vs, x, y, w, h, zywrle_level);
            }
        }
    }
    break;
    }

    vnc_zrle_stop(vs);
    bytes = zrle_compress_data(vs, Z_DEFAULT_COMPRESSION);
    vnc_framebuffer_update(vs, x, y, w, h, vs->zrle.type);
    vnc_write_u32(vs, bytes);
    vnc_write(vs, vs->zrle.zlib.buffer, vs->zrle.zlib.offset);
    return 1;
}

int vnc_zrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h)
{
    vs->zrle.type = VNC_ENCODING_ZRLE;
    return zrle_send_framebuffer_update(vs, x, y, w, h);
}

int vnc_zywrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h)
{
    vs->zrle.type = VNC_ENCODING_ZYWRLE;
    return zrle_send_framebuffer_update(vs, x, y, w, h);
}

void vnc_zrle_clear(VncState *vs)
{
    if (vs->zrle.stream.opaque) {
        deflateEnd(&vs->zrle.stream);
    }
    buffer_free(&vs->zrle.zrle);
    buffer_free(&vs->zrle.fb);
    buffer_free(&vs->zrle.zlib);
}