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 "qemu/osdep.h"
  30#include "vnc.h"
  31#include "vnc-enc-zrle.h"
  32
  33static const int bits_per_packed_pixel[] = {
  34  0, 1, 2, 2, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4
  35};
  36
  37
  38static void vnc_zrle_start(VncState *vs)
  39{
  40    buffer_reset(&vs->zrle.zrle);
  41
  42    /* make the output buffer be the zlib buffer, so we can compress it later */
  43    vs->zrle.tmp = vs->output;
  44    vs->output = vs->zrle.zrle;
  45}
  46
  47static void vnc_zrle_stop(VncState *vs)
  48{
  49    /* switch back to normal output/zlib buffers */
  50    vs->zrle.zrle = vs->output;
  51    vs->output = vs->zrle.tmp;
  52}
  53
  54static void *zrle_convert_fb(VncState *vs, int x, int y, int w, int h,
  55                             int bpp)
  56{
  57    Buffer tmp;
  58
  59    buffer_reset(&vs->zrle.fb);
  60    buffer_reserve(&vs->zrle.fb, w * h * bpp + bpp);
  61
  62    tmp = vs->output;
  63    vs->output = vs->zrle.fb;
  64
  65    vnc_raw_send_framebuffer_update(vs, x, y, w, h);
  66
  67    vs->zrle.fb = vs->output;
  68    vs->output = tmp;
  69    return vs->zrle.fb.buffer;
  70}
  71
  72static int zrle_compress_data(VncState *vs, int level)
  73{
  74    z_streamp zstream = &vs->zrle.stream;
  75
  76    buffer_reset(&vs->zrle.zlib);
  77
  78    if (zstream->opaque != vs) {
  79        int err;
  80
  81        zstream->zalloc = vnc_zlib_zalloc;
  82        zstream->zfree = vnc_zlib_zfree;
  83
  84        err = deflateInit2(zstream, level, Z_DEFLATED, MAX_WBITS,
  85                           MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY);
  86
  87        if (err != Z_OK) {
  88            fprintf(stderr, "VNC: error initializing zlib\n");
  89            return -1;
  90        }
  91
  92        zstream->opaque = vs;
  93    }
  94
  95    /* reserve memory in output buffer */
  96    buffer_reserve(&vs->zrle.zlib, vs->zrle.zrle.offset + 64);
  97
  98    /* set pointers */
  99    zstream->next_in = vs->zrle.zrle.buffer;
 100    zstream->avail_in = vs->zrle.zrle.offset;
 101    zstream->next_out = vs->zrle.zlib.buffer + vs->zrle.zlib.offset;
 102    zstream->avail_out = vs->zrle.zlib.capacity - vs->zrle.zlib.offset;
 103    zstream->data_type = Z_BINARY;
 104
 105    /* start encoding */
 106    if (deflate(zstream, Z_SYNC_FLUSH) != Z_OK) {
 107        fprintf(stderr, "VNC: error during zrle compression\n");
 108        return -1;
 109    }
 110
 111    vs->zrle.zlib.offset = vs->zrle.zlib.capacity - zstream->avail_out;
 112    return vs->zrle.zlib.offset;
 113}
 114
 115/* Try to work out whether to use RLE and/or a palette.  We do this by
 116 * estimating the number of bytes which will be generated and picking the
 117 * method which results in the fewest bytes.  Of course this may not result
 118 * in the fewest bytes after compression... */
 119static void zrle_choose_palette_rle(VncState *vs, int w, int h,
 120                                    VncPalette *palette, int bpp_out,
 121                                    int runs, int single_pixels,
 122                                    int zywrle_level,
 123                                    bool *use_rle, bool *use_palette)
 124{
 125    size_t estimated_bytes;
 126    size_t plain_rle_bytes;
 127
 128    *use_palette = *use_rle = false;
 129
 130    estimated_bytes = w * h * (bpp_out / 8); /* start assuming raw */
 131
 132    if (bpp_out != 8) {
 133        if (zywrle_level > 0 && !(zywrle_level & 0x80))
 134            estimated_bytes >>= zywrle_level;
 135    }
 136
 137    plain_rle_bytes = ((bpp_out / 8) + 1) * (runs + single_pixels);
 138
 139    if (plain_rle_bytes < estimated_bytes) {
 140        *use_rle = true;
 141        estimated_bytes = plain_rle_bytes;
 142    }
 143
 144    if (palette_size(palette) < 128) {
 145        int palette_rle_bytes;
 146
 147        palette_rle_bytes = (bpp_out / 8) * palette_size(palette);
 148        palette_rle_bytes += 2 * runs + single_pixels;
 149
 150        if (palette_rle_bytes < estimated_bytes) {
 151            *use_rle = true;
 152            *use_palette = true;
 153            estimated_bytes = palette_rle_bytes;
 154        }
 155
 156        if (palette_size(palette) < 17) {
 157            int packed_bytes;
 158
 159            packed_bytes = (bpp_out / 8) * palette_size(palette);
 160            packed_bytes += w * h *
 161                bits_per_packed_pixel[palette_size(palette)-1] / 8;
 162
 163            if (packed_bytes < estimated_bytes) {
 164                *use_rle = false;
 165                *use_palette = true;
 166                estimated_bytes = packed_bytes;
 167            }
 168        }
 169    }
 170}
 171
 172static void zrle_write_u32(VncState *vs, uint32_t value)
 173{
 174    vnc_write(vs, (uint8_t *)&value, 4);
 175}
 176
 177static void zrle_write_u24a(VncState *vs, uint32_t value)
 178{
 179    vnc_write(vs, (uint8_t *)&value, 3);
 180}
 181
 182static void zrle_write_u24b(VncState *vs, uint32_t value)
 183{
 184    vnc_write(vs, ((uint8_t *)&value) + 1, 3);
 185}
 186
 187static void zrle_write_u16(VncState *vs, uint16_t value)
 188{
 189    vnc_write(vs, (uint8_t *)&value, 2);
 190}
 191
 192static void zrle_write_u8(VncState *vs, uint8_t value)
 193{
 194    vnc_write_u8(vs, value);
 195}
 196
 197#define ENDIAN_LITTLE 0
 198#define ENDIAN_BIG    1
 199#define ENDIAN_NO     2
 200
 201#define ZRLE_BPP 8
 202#define ZYWRLE_ENDIAN ENDIAN_NO
 203#include "vnc-enc-zrle-template.c"
 204#undef ZRLE_BPP
 205
 206#define ZRLE_BPP 15
 207#undef ZYWRLE_ENDIAN
 208#define ZYWRLE_ENDIAN ENDIAN_LITTLE
 209#include "vnc-enc-zrle-template.c"
 210
 211#undef ZYWRLE_ENDIAN
 212#define ZYWRLE_ENDIAN ENDIAN_BIG
 213#include "vnc-enc-zrle-template.c"
 214
 215#undef ZRLE_BPP
 216#define ZRLE_BPP 16
 217#undef ZYWRLE_ENDIAN
 218#define ZYWRLE_ENDIAN ENDIAN_LITTLE
 219#include "vnc-enc-zrle-template.c"
 220
 221#undef ZYWRLE_ENDIAN
 222#define ZYWRLE_ENDIAN ENDIAN_BIG
 223#include "vnc-enc-zrle-template.c"
 224
 225#undef ZRLE_BPP
 226#define ZRLE_BPP 32
 227#undef ZYWRLE_ENDIAN
 228#define ZYWRLE_ENDIAN ENDIAN_LITTLE
 229#include "vnc-enc-zrle-template.c"
 230
 231#undef ZYWRLE_ENDIAN
 232#define ZYWRLE_ENDIAN ENDIAN_BIG
 233#include "vnc-enc-zrle-template.c"
 234
 235#define ZRLE_COMPACT_PIXEL 24a
 236#undef ZYWRLE_ENDIAN
 237#define ZYWRLE_ENDIAN ENDIAN_LITTLE
 238#include "vnc-enc-zrle-template.c"
 239
 240#undef ZYWRLE_ENDIAN
 241#define ZYWRLE_ENDIAN ENDIAN_BIG
 242#include "vnc-enc-zrle-template.c"
 243
 244#undef ZRLE_COMPACT_PIXEL
 245#define ZRLE_COMPACT_PIXEL 24b
 246#undef ZYWRLE_ENDIAN
 247#define ZYWRLE_ENDIAN ENDIAN_LITTLE
 248#include "vnc-enc-zrle-template.c"
 249
 250#undef ZYWRLE_ENDIAN
 251#define ZYWRLE_ENDIAN ENDIAN_BIG
 252#include "vnc-enc-zrle-template.c"
 253#undef ZRLE_COMPACT_PIXEL
 254#undef ZRLE_BPP
 255
 256static int zrle_send_framebuffer_update(VncState *vs, int x, int y,
 257                                        int w, int h)
 258{
 259    bool be = vs->client_be;
 260    size_t bytes;
 261    int zywrle_level;
 262
 263    if (vs->zrle.type == VNC_ENCODING_ZYWRLE) {
 264        if (!vs->vd->lossy || vs->tight.quality == (uint8_t)-1
 265            || vs->tight.quality == 9) {
 266            zywrle_level = 0;
 267            vs->zrle.type = VNC_ENCODING_ZRLE;
 268        } else if (vs->tight.quality < 3) {
 269            zywrle_level = 3;
 270        } else if (vs->tight.quality < 6) {
 271            zywrle_level = 2;
 272        } else {
 273            zywrle_level = 1;
 274        }
 275    } else {
 276        zywrle_level = 0;
 277    }
 278
 279    vnc_zrle_start(vs);
 280
 281    switch (vs->client_pf.bytes_per_pixel) {
 282    case 1:
 283        zrle_encode_8ne(vs, x, y, w, h, zywrle_level);
 284        break;
 285
 286    case 2:
 287        if (vs->client_pf.gmax > 0x1F) {
 288            if (be) {
 289                zrle_encode_16be(vs, x, y, w, h, zywrle_level);
 290            } else {
 291                zrle_encode_16le(vs, x, y, w, h, zywrle_level);
 292            }
 293        } else {
 294            if (be) {
 295                zrle_encode_15be(vs, x, y, w, h, zywrle_level);
 296            } else {
 297                zrle_encode_15le(vs, x, y, w, h, zywrle_level);
 298            }
 299        }
 300        break;
 301
 302    case 4:
 303    {
 304        bool fits_in_ls3bytes;
 305        bool fits_in_ms3bytes;
 306
 307        fits_in_ls3bytes =
 308            ((vs->client_pf.rmax << vs->client_pf.rshift) < (1 << 24) &&
 309             (vs->client_pf.gmax << vs->client_pf.gshift) < (1 << 24) &&
 310             (vs->client_pf.bmax << vs->client_pf.bshift) < (1 << 24));
 311
 312        fits_in_ms3bytes = (vs->client_pf.rshift > 7 &&
 313                            vs->client_pf.gshift > 7 &&
 314                            vs->client_pf.bshift > 7);
 315
 316        if ((fits_in_ls3bytes && !be) || (fits_in_ms3bytes && be)) {
 317            if (be) {
 318                zrle_encode_24abe(vs, x, y, w, h, zywrle_level);
 319            } else {
 320                zrle_encode_24ale(vs, x, y, w, h, zywrle_level);
 321          }
 322        } else if ((fits_in_ls3bytes && be) || (fits_in_ms3bytes && !be)) {
 323            if (be) {
 324                zrle_encode_24bbe(vs, x, y, w, h, zywrle_level);
 325            } else {
 326                zrle_encode_24ble(vs, x, y, w, h, zywrle_level);
 327            }
 328        } else {
 329            if (be) {
 330                zrle_encode_32be(vs, x, y, w, h, zywrle_level);
 331            } else {
 332                zrle_encode_32le(vs, x, y, w, h, zywrle_level);
 333            }
 334        }
 335    }
 336    break;
 337    }
 338
 339    vnc_zrle_stop(vs);
 340    bytes = zrle_compress_data(vs, Z_DEFAULT_COMPRESSION);
 341    vnc_framebuffer_update(vs, x, y, w, h, vs->zrle.type);
 342    vnc_write_u32(vs, bytes);
 343    vnc_write(vs, vs->zrle.zlib.buffer, vs->zrle.zlib.offset);
 344    return 1;
 345}
 346
 347int vnc_zrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h)
 348{
 349    vs->zrle.type = VNC_ENCODING_ZRLE;
 350    return zrle_send_framebuffer_update(vs, x, y, w, h);
 351}
 352
 353int vnc_zywrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h)
 354{
 355    vs->zrle.type = VNC_ENCODING_ZYWRLE;
 356    return zrle_send_framebuffer_update(vs, x, y, w, h);
 357}
 358
 359void vnc_zrle_clear(VncState *vs)
 360{
 361    if (vs->zrle.stream.opaque) {
 362        deflateEnd(&vs->zrle.stream);
 363    }
 364    buffer_free(&vs->zrle.zrle);
 365    buffer_free(&vs->zrle.fb);
 366    buffer_free(&vs->zrle.zlib);
 367}
 368