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Diffstat (limited to 'vnc-encoding-tight.c')
| -rw-r--r-- | vnc-encoding-tight.c | 295 |
1 files changed, 295 insertions, 0 deletions
diff --git a/vnc-encoding-tight.c b/vnc-encoding-tight.c new file mode 100644 index 0000000..ce9cc49 --- /dev/null +++ b/vnc-encoding-tight.c @@ -0,0 +1,295 @@ +/* + * QEMU VNC display driver: tight encoding + * + * From libvncserver/libvncserver/tight.c + * Copyright (C) 2000, 2001 Const Kaplinsky. All Rights Reserved. + * Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved. + * + * 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 <stdbool.h> + +#include "vnc.h" +#include "vnc-encoding-tight.h" + +/* Compression level stuff. The following array contains various + encoder parameters for each of 10 compression levels (0..9). + Last three parameters correspond to JPEG quality levels (0..9). */ + +static const struct { + int max_rect_size, max_rect_width; + int mono_min_rect_size, gradient_min_rect_size; + int idx_zlib_level, mono_zlib_level, raw_zlib_level, gradient_zlib_level; + int gradient_threshold, gradient_threshold24; + int idx_max_colors_divisor; + int jpeg_quality, jpeg_threshold, jpeg_threshold24; +} tight_conf[] = { + { 512, 32, 6, 65536, 0, 0, 0, 0, 0, 0, 4, 5, 10000, 23000 }, + { 2048, 128, 6, 65536, 1, 1, 1, 0, 0, 0, 8, 10, 8000, 18000 }, + { 6144, 256, 8, 65536, 3, 3, 2, 0, 0, 0, 24, 15, 6500, 15000 }, + { 10240, 1024, 12, 65536, 5, 5, 3, 0, 0, 0, 32, 25, 5000, 12000 }, + { 16384, 2048, 12, 65536, 6, 6, 4, 0, 0, 0, 32, 37, 4000, 10000 }, + { 32768, 2048, 12, 4096, 7, 7, 5, 4, 150, 380, 32, 50, 3000, 8000 }, + { 65536, 2048, 16, 4096, 7, 7, 6, 4, 170, 420, 48, 60, 2000, 5000 }, + { 65536, 2048, 16, 4096, 8, 8, 7, 5, 180, 450, 64, 70, 1000, 2500 }, + { 65536, 2048, 32, 8192, 9, 9, 8, 6, 190, 475, 64, 75, 500, 1200 }, + { 65536, 2048, 32, 8192, 9, 9, 9, 6, 200, 500, 96, 80, 200, 500 } +}; + +static int tight_init_stream(VncState *vs, int stream_id, + int level, int strategy) +{ + z_streamp zstream = &vs->tight_stream[stream_id]; + + if (zstream->opaque == NULL) { + int err; + + VNC_DEBUG("VNC: TIGHT: initializing zlib stream %d\n", stream_id); + VNC_DEBUG("VNC: TIGHT: opaque = %p | vs = %p\n", zstream->opaque, vs); + zstream->zalloc = vnc_zlib_zalloc; + zstream->zfree = vnc_zlib_zfree; + + err = deflateInit2(zstream, level, Z_DEFLATED, MAX_WBITS, + MAX_MEM_LEVEL, strategy); + + if (err != Z_OK) { + fprintf(stderr, "VNC: error initializing zlib\n"); + return -1; + } + + vs->tight_levels[stream_id] = level; + zstream->opaque = vs; + } + + if (vs->tight_levels[stream_id] != level) { + if (deflateParams(zstream, level, strategy) != Z_OK) { + return -1; + } + vs->tight_levels[stream_id] = level; + } + return 0; +} + +static void tight_send_compact_size(VncState *vs, size_t len) +{ + int lpc = 0; + int bytes = 0; + char buf[3] = {0, 0, 0}; + + buf[bytes++] = len & 0x7F; + if (len > 0x7F) { + buf[bytes-1] |= 0x80; + buf[bytes++] = (len >> 7) & 0x7F; + if (len > 0x3FFF) { + buf[bytes-1] |= 0x80; + buf[bytes++] = (len >> 14) & 0xFF; + } + } + for(lpc = 0; lpc < bytes; lpc++) { + vnc_write_u8(vs, buf[lpc]); + } +} + +static int tight_compress_data(VncState *vs, int stream_id, size_t bytes, + int level, int strategy) +{ + z_streamp zstream = &vs->tight_stream[stream_id]; + int previous_out; + + if (bytes < VNC_TIGHT_MIN_TO_COMPRESS) { + vnc_write(vs, vs->tight.buffer, vs->tight.offset); + return bytes; + } + + if (tight_init_stream(vs, stream_id, level, strategy)) { + return -1; + } + + /* reserve memory in output buffer */ + buffer_reserve(&vs->tight_zlib, bytes + 64); + + /* set pointers */ + zstream->next_in = vs->tight.buffer; + zstream->avail_in = vs->tight.offset; + zstream->next_out = vs->tight_zlib.buffer + vs->tight_zlib.offset; + zstream->avail_out = vs->tight_zlib.capacity - vs->tight_zlib.offset; + zstream->data_type = Z_BINARY; + previous_out = zstream->total_out; + + /* start encoding */ + if (deflate(zstream, Z_SYNC_FLUSH) != Z_OK) { + fprintf(stderr, "VNC: error during tight compression\n"); + return -1; + } + + vs->tight_zlib.offset = vs->tight_zlib.capacity - zstream->avail_out; + bytes = zstream->total_out - previous_out; + + tight_send_compact_size(vs, bytes); + vnc_write(vs, vs->tight_zlib.buffer, bytes); + + buffer_reset(&vs->tight_zlib); + + return bytes; +} + +/* + * Subencoding implementations. + */ +static void tight_pack24(VncState *vs, size_t count) +{ + unsigned char *buf; + uint32_t *buf32; + uint32_t pix; + int rshift, gshift, bshift; + + buf = vs->tight.buffer; + buf32 = (uint32_t *)buf; + + if ((vs->clientds.flags & QEMU_BIG_ENDIAN_FLAG) == + (vs->ds->surface->flags & QEMU_BIG_ENDIAN_FLAG)) { + rshift = vs->clientds.pf.rshift; + gshift = vs->clientds.pf.gshift; + bshift = vs->clientds.pf.bshift; + } else { + rshift = 24 - vs->clientds.pf.rshift; + gshift = 24 - vs->clientds.pf.gshift; + bshift = 24 - vs->clientds.pf.bshift; + } + + vs->tight.offset = count * 3; + + while (count--) { + pix = *buf32++; + *buf++ = (char)(pix >> rshift); + *buf++ = (char)(pix >> gshift); + *buf++ = (char)(pix >> bshift); + } +} + +static int send_full_color_rect(VncState *vs, int w, int h) +{ + int stream = 0; + size_t bytes; + + vnc_write_u8(vs, stream << 4); /* no flushing, no filter */ + + if (vs->tight_pixel24) { + tight_pack24(vs, w * h); + bytes = 3; + } else { + bytes = vs->clientds.pf.bytes_per_pixel; + } + + bytes = tight_compress_data(vs, stream, w * h * bytes, + tight_conf[vs->tight_compression].raw_zlib_level, + Z_DEFAULT_STRATEGY); + + return (bytes >= 0); +} + +static void vnc_tight_start(VncState *vs) +{ + buffer_reset(&vs->tight); + + // make the output buffer be the zlib buffer, so we can compress it later + vs->tight_tmp = vs->output; + vs->output = vs->tight; +} + +static void vnc_tight_stop(VncState *vs) +{ + // switch back to normal output/zlib buffers + vs->tight = vs->output; + vs->output = vs->tight_tmp; +} + +static int send_sub_rect(VncState *vs, int x, int y, int w, int h) +{ + vnc_framebuffer_update(vs, x, y, w, h, VNC_ENCODING_TIGHT); + + /* + * Convert pixels and store them in vs->tight + * We will probably rework that later, probably + * when adding other sub-encodings + */ + vnc_tight_start(vs); + vnc_raw_send_framebuffer_update(vs, x, y, w, h); + vnc_tight_stop(vs); + + return send_full_color_rect(vs, w, h); +} + +static int send_rect_simple(VncState *vs, int x, int y, int w, int h) +{ + int max_size, max_width; + int max_sub_width, max_sub_height; + int dx, dy; + int rw, rh; + int n = 0; + + max_size = tight_conf[vs->tight_compression].max_rect_size; + max_width = tight_conf[vs->tight_compression].max_rect_width; + + if (w > max_width || w * h > max_size) { + max_sub_width = (w > max_width) ? max_width : w; + max_sub_height = max_size / max_sub_width; + + for (dy = 0; dy < h; dy += max_sub_height) { + for (dx = 0; dx < w; dx += max_width) { + rw = MIN(max_sub_width, w - dx); + rh = MIN(max_sub_height, h - dy); + n += send_sub_rect(vs, x+dx, y+dy, rw, rh); + } + } + } else { + n += send_sub_rect(vs, x, y, w, h); + } + + return n; +} + +int vnc_tight_send_framebuffer_update(VncState *vs, int x, int y, + int w, int h) +{ + if (vs->clientds.pf.bytes_per_pixel == 4 && vs->clientds.pf.rmax == 0xFF && + vs->clientds.pf.bmax == 0xFF && vs->clientds.pf.gmax == 0xFF) { + vs->tight_pixel24 = true; + } else { + vs->tight_pixel24 = false; + } + + return send_rect_simple(vs, x, y, w, h); +} + +void vnc_tight_clear(VncState *vs) +{ + int i; + for (i=0; i<ARRAY_SIZE(vs->tight_stream); i++) { + if (vs->tight_stream[i].opaque) { + deflateEnd(&vs->tight_stream[i]); + } + } + + buffer_free(&vs->tight); + buffer_free(&vs->tight_zlib); +} |