LXR qemu/ui/vnc-enc-zrle.c

   1/*
   2 * QEMU VNC display driver: Zlib Run-length Encoding (ZRLE)
   3 *
   4 * From libvncserver/libvncserver/zrle.c
   5 * Copyright (C) 2002 RealVNC Ltd.  All Rights Reserved.
   6 * Copyright (C) 2003 Sun Microsystems, Inc.
   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 "vnc.h"
  30#include "vnc-enc-zrle.h"
  31
  32static const int bits_per_packed_pixel[] = {
  33  0, 1, 2, 2, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4
  34};
  35
  36
  37static void vnc_zrle_start(VncState *vs)
  38{
  39    buffer_reset(&vs->zrle.zrle);
  40
  41    /* make the output buffer be the zlib buffer, so we can compress it later */
  42    vs->zrle.tmp = vs->output;
  43    vs->output = vs->zrle.zrle;
  44}
  45
  46static void vnc_zrle_stop(VncState *vs)
  47{
  48    /* switch back to normal output/zlib buffers */
  49    vs->zrle.zrle = vs->output;
  50    vs->output = vs->zrle.tmp;
  51}
  52
  53static void *zrle_convert_fb(VncState *vs, int x, int y, int w, int h,
  54                             int bpp)
  55{
  56    Buffer tmp;
  57
  58    buffer_reset(&vs->zrle.fb);
  59    buffer_reserve(&vs->zrle.fb, w * h * bpp + bpp);
  60
  61    tmp = vs->output;
  62    vs->output = vs->zrle.fb;
  63
  64    vnc_raw_send_framebuffer_update(vs, x, y, w, h);
  65
  66    vs->zrle.fb = vs->output;
  67    vs->output = tmp;
  68    return vs->zrle.fb.buffer;
  69}
  70
  71static int zrle_compress_data(VncState *vs, int level)
  72{
  73    z_streamp zstream = &vs->zrle.stream;
  74
  75    buffer_reset(&vs->zrle.zlib);
  76
  77    if (zstream->opaque != vs) {
  78        int err;
  79
  80        zstream->zalloc = vnc_zlib_zalloc;
  81        zstream->zfree = vnc_zlib_zfree;
  82
  83        err = deflateInit2(zstream, level, Z_DEFLATED, MAX_WBITS,
  84                           MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY);
  85
  86        if (err != Z_OK) {
  87            fprintf(stderr, "VNC: error initializing zlib\n");
  88            return -1;
  89        }
  90
  91        zstream->opaque = vs;
  92    }
  93
  94    /* reserve memory in output buffer */
  95    buffer_reserve(&vs->zrle.zlib, vs->zrle.zrle.offset + 64);
  96
  97    /* set pointers */
  98    zstream->next_in = vs->zrle.zrle.buffer;
  99    zstream->avail_in = vs->zrle.zrle.offset;
 100    zstream->next_out = vs->zrle.zlib.buffer + vs->zrle.zlib.offset;
 101    zstream->avail_out = vs->zrle.zlib.capacity - vs->zrle.zlib.offset;
 102    zstream->data_type = Z_BINARY;
 103
 104    /* start encoding */
 105    if (deflate(zstream, Z_SYNC_FLUSH) != Z_OK) {
 106        fprintf(stderr, "VNC: error during zrle compression\n");
 107        return -1;
 108    }
 109
 110    vs->zrle.zlib.offset = vs->zrle.zlib.capacity - zstream->avail_out;
 111    return vs->zrle.zlib.offset;
 112}
 113
 114/* Try to work out whether to use RLE and/or a palette.  We do this by
 115 * estimating the number of bytes which will be generated and picking the
 116 * method which results in the fewest bytes.  Of course this may not result
 117 * in the fewest bytes after compression... */
 118static void zrle_choose_palette_rle(VncState *vs, int w, int h,
 119                                    VncPalette *palette, int bpp_out,
 120                                    int runs, int single_pixels,
 121                                    int zywrle_level,
 122                                    bool *use_rle, bool *use_palette)
 123{
 124    size_t estimated_bytes;
 125    size_t plain_rle_bytes;
 126
 127    *use_palette = *use_rle = false;
 128
 129    estimated_bytes = w * h * (bpp_out / 8); /* start assuming raw */
 130
 131    if (bpp_out != 8) {
 132        if (zywrle_level > 0 && !(zywrle_level & 0x80))
 133            estimated_bytes >>= zywrle_level;
 134    }
 135
 136    plain_rle_bytes = ((bpp_out / 8) + 1) * (runs + single_pixels);
 137
 138    if (plain_rle_bytes < estimated_bytes) {
 139        *use_rle = true;
 140        estimated_bytes = plain_rle_bytes;
 141    }
 142
 143    if (palette_size(palette) < 128) {
 144        int palette_rle_bytes;
 145
 146        palette_rle_bytes = (bpp_out / 8) * palette_size(palette);
 147        palette_rle_bytes += 2 * runs + single_pixels;
 148
 149        if (palette_rle_bytes < estimated_bytes) {
 150            *use_rle = true;
 151            *use_palette = true;
 152            estimated_bytes = palette_rle_bytes;
 153        }
 154
 155        if (palette_size(palette) < 17) {
 156            int packed_bytes;
 157
 158            packed_bytes = (bpp_out / 8) * palette_size(palette);
 159            packed_bytes += w * h *
 160                bits_per_packed_pixel[palette_size(palette)-1] / 8;
 161
 162            if (packed_bytes < estimated_bytes) {
 163                *use_rle = false;
 164                *use_palette = true;
 165                estimated_bytes = packed_bytes;
 166            }
 167        }
 168    }
 169}
 170
 171static void zrle_write_u32(VncState *vs, uint32_t value)
 172{
 173    vnc_write(vs, (uint8_t *)&value, 4);
 174}
 175
 176static void zrle_write_u24a(VncState *vs, uint32_t value)
 177{
 178    vnc_write(vs, (uint8_t *)&value, 3);
 179}
 180
 181static void zrle_write_u24b(VncState *vs, uint32_t value)
 182{
 183    vnc_write(vs, ((uint8_t *)&value) + 1, 3);
 184}
 185
 186static void zrle_write_u16(VncState *vs, uint16_t value)
 187{
 188    vnc_write(vs, (uint8_t *)&value, 2);
 189}
 190
 191static void zrle_write_u8(VncState *vs, uint8_t value)
 192{
 193    vnc_write_u8(vs, value);
 194}
 195
 196#define ENDIAN_LITTLE 0
 197#define ENDIAN_BIG    1
 198#define ENDIAN_NO     2
 199
 200#define ZRLE_BPP 8
 201#define ZYWRLE_ENDIAN ENDIAN_NO
 202#include "vnc-enc-zrle-template.c"
 203#undef ZRLE_BPP
 204
 205#define ZRLE_BPP 15
 206#undef ZYWRLE_ENDIAN
 207#define ZYWRLE_ENDIAN ENDIAN_LITTLE
 208#include "vnc-enc-zrle-template.c"
 209
 210#undef ZYWRLE_ENDIAN
 211#define ZYWRLE_ENDIAN ENDIAN_BIG
 212#include "vnc-enc-zrle-template.c"
 213
 214#undef ZRLE_BPP
 215#define ZRLE_BPP 16
 216#undef ZYWRLE_ENDIAN
 217#define ZYWRLE_ENDIAN ENDIAN_LITTLE
 218#include "vnc-enc-zrle-template.c"
 219
 220#undef ZYWRLE_ENDIAN
 221#define ZYWRLE_ENDIAN ENDIAN_BIG
 222#include "vnc-enc-zrle-template.c"
 223
 224#undef ZRLE_BPP
 225#define ZRLE_BPP 32
 226#undef ZYWRLE_ENDIAN
 227#define ZYWRLE_ENDIAN ENDIAN_LITTLE
 228#include "vnc-enc-zrle-template.c"
 229
 230#undef ZYWRLE_ENDIAN
 231#define ZYWRLE_ENDIAN ENDIAN_BIG
 232#include "vnc-enc-zrle-template.c"
 233
 234#define ZRLE_COMPACT_PIXEL 24a
 235#undef ZYWRLE_ENDIAN
 236#define ZYWRLE_ENDIAN ENDIAN_LITTLE
 237#include "vnc-enc-zrle-template.c"
 238
 239#undef ZYWRLE_ENDIAN
 240#define ZYWRLE_ENDIAN ENDIAN_BIG
 241#include "vnc-enc-zrle-template.c"
 242
 243#undef ZRLE_COMPACT_PIXEL
 244#define ZRLE_COMPACT_PIXEL 24b
 245#undef ZYWRLE_ENDIAN
 246#define ZYWRLE_ENDIAN ENDIAN_LITTLE
 247#include "vnc-enc-zrle-template.c"
 248
 249#undef ZYWRLE_ENDIAN
 250#define ZYWRLE_ENDIAN ENDIAN_BIG
 251#include "vnc-enc-zrle-template.c"
 252#undef ZRLE_COMPACT_PIXEL
 253#undef ZRLE_BPP
 254
 255static int zrle_send_framebuffer_update(VncState *vs, int x, int y,
 256                                        int w, int h)
 257{
 258    bool be = vs->client_be;
 259    size_t bytes;
 260    int zywrle_level;
 261
 262    if (vs->zrle.type == VNC_ENCODING_ZYWRLE) {
 263        if (!vs->vd->lossy || vs->tight.quality == (uint8_t)-1
 264            || vs->tight.quality == 9) {
 265            zywrle_level = 0;
 266            vs->zrle.type = VNC_ENCODING_ZRLE;
 267        } else if (vs->tight.quality < 3) {
 268            zywrle_level = 3;
 269        } else if (vs->tight.quality < 6) {
 270            zywrle_level = 2;
 271        } else {
 272            zywrle_level = 1;
 273        }
 274    } else {
 275        zywrle_level = 0;
 276    }
 277
 278    vnc_zrle_start(vs);
 279
 280    switch (vs->client_pf.bytes_per_pixel) {
 281    case 1:
 282        zrle_encode_8ne(vs, x, y, w, h, zywrle_level);
 283        break;
 284
 285    case 2:
 286        if (vs->client_pf.gmax > 0x1F) {
 287            if (be) {
 288                zrle_encode_16be(vs, x, y, w, h, zywrle_level);
 289            } else {
 290                zrle_encode_16le(vs, x, y, w, h, zywrle_level);
 291            }
 292        } else {
 293            if (be) {
 294                zrle_encode_15be(vs, x, y, w, h, zywrle_level);
 295            } else {
 296                zrle_encode_15le(vs, x, y, w, h, zywrle_level);
 297            }
 298        }
 299        break;
 300
 301    case 4:
 302    {
 303        bool fits_in_ls3bytes;
 304        bool fits_in_ms3bytes;
 305
 306        fits_in_ls3bytes =
 307            ((vs->client_pf.rmax << vs->client_pf.rshift) < (1 << 24) &&
 308             (vs->client_pf.gmax << vs->client_pf.gshift) < (1 << 24) &&
 309             (vs->client_pf.bmax << vs->client_pf.bshift) < (1 << 24));
 310
 311        fits_in_ms3bytes = (vs->client_pf.rshift > 7 &&
 312                            vs->client_pf.gshift > 7 &&
 313                            vs->client_pf.bshift > 7);
 314
 315        if ((fits_in_ls3bytes && !be) || (fits_in_ms3bytes && be)) {
 316            if (be) {
 317                zrle_encode_24abe(vs, x, y, w, h, zywrle_level);
 318            } else {
 319                zrle_encode_24ale(vs, x, y, w, h, zywrle_level);
 320          }
 321        } else if ((fits_in_ls3bytes && be) || (fits_in_ms3bytes && !be)) {
 322            if (be) {
 323                zrle_encode_24bbe(vs, x, y, w, h, zywrle_level);
 324            } else {
 325                zrle_encode_24ble(vs, x, y, w, h, zywrle_level);
 326            }
 327        } else {
 328            if (be) {
 329                zrle_encode_32be(vs, x, y, w, h, zywrle_level);
 330            } else {
 331                zrle_encode_32le(vs, x, y, w, h, zywrle_level);
 332            }
 333        }
 334    }
 335    break;
 336    }
 337
 338    vnc_zrle_stop(vs);
 339    bytes = zrle_compress_data(vs, Z_DEFAULT_COMPRESSION);
 340    vnc_framebuffer_update(vs, x, y, w, h, vs->zrle.type);
 341    vnc_write_u32(vs, bytes);
 342    vnc_write(vs, vs->zrle.zlib.buffer, vs->zrle.zlib.offset);
 343    return 1;
 344}
 345
 346int vnc_zrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h)
 347{
 348    vs->zrle.type = VNC_ENCODING_ZRLE;
 349    return zrle_send_framebuffer_update(vs, x, y, w, h);
 350}
 351
 352int vnc_zywrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h)
 353{
 354    vs->zrle.type = VNC_ENCODING_ZYWRLE;
 355    return zrle_send_framebuffer_update(vs, x, y, w, h);
 356}
 357
 358void vnc_zrle_clear(VncState *vs)
 359{
 360    if (vs->zrle.stream.opaque) {
 361        deflateEnd(&vs->zrle.stream);
 362    }
 363    buffer_free(&vs->zrle.zrle);
 364    buffer_free(&vs->zrle.fb);
 365    buffer_free(&vs->zrle.zlib);
 366}
 367