/*
* 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);
}
