qemu/vnc-encoding-tight.c
Paul Brook 11165820d1 Move stdbool.h
Move inclusion of stdbool.h to common header files, instead of including
in an ad-hoc manner.

Signed-off-by: Paul Brook <paul@codesourcery.com>
2010-06-13 19:00:50 +01:00

960 lines
36 KiB
C

/*
* 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 "qdict.h"
#include "qint.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 }
};
/*
* Code to determine how many different colors used in rectangle.
*/
static void tight_palette_rgb2buf(uint32_t rgb, int bpp, uint8_t buf[6])
{
memset(buf, 0, 6);
if (bpp == 32) {
buf[0] = ((rgb >> 24) & 0xFF);
buf[1] = ((rgb >> 16) & 0xFF);
buf[2] = ((rgb >> 8) & 0xFF);
buf[3] = ((rgb >> 0) & 0xFF);
buf[4] = ((buf[0] & 1) == 0) << 3 | ((buf[1] & 1) == 0) << 2;
buf[4]|= ((buf[2] & 1) == 0) << 1 | ((buf[3] & 1) == 0) << 0;
buf[0] |= 1;
buf[1] |= 1;
buf[2] |= 1;
buf[3] |= 1;
}
if (bpp == 16) {
buf[0] = ((rgb >> 8) & 0xFF);
buf[1] = ((rgb >> 0) & 0xFF);
buf[2] = ((buf[0] & 1) == 0) << 1 | ((buf[1] & 1) == 0) << 0;
buf[0] |= 1;
buf[1] |= 1;
}
}
static uint32_t tight_palette_buf2rgb(int bpp, const uint8_t *buf)
{
uint32_t rgb = 0;
if (bpp == 32) {
rgb |= ((buf[0] & ~1) | !((buf[4] >> 3) & 1)) << 24;
rgb |= ((buf[1] & ~1) | !((buf[4] >> 2) & 1)) << 16;
rgb |= ((buf[2] & ~1) | !((buf[4] >> 1) & 1)) << 8;
rgb |= ((buf[3] & ~1) | !((buf[4] >> 0) & 1)) << 0;
}
if (bpp == 16) {
rgb |= ((buf[0] & ~1) | !((buf[2] >> 1) & 1)) << 8;
rgb |= ((buf[1] & ~1) | !((buf[2] >> 0) & 1)) << 0;
}
return rgb;
}
static int tight_palette_insert(QDict *palette, uint32_t rgb, int bpp, int max)
{
uint8_t key[6];
int idx = qdict_size(palette);
bool present;
tight_palette_rgb2buf(rgb, bpp, key);
present = qdict_haskey(palette, (char *)key);
if (idx >= max && !present) {
return 0;
}
if (!present) {
qdict_put(palette, (char *)key, qint_from_int(idx));
}
return qdict_size(palette);
}
#define DEFINE_FILL_PALETTE_FUNCTION(bpp) \
\
static int \
tight_fill_palette##bpp(VncState *vs, int x, int y, \
int max, size_t count, \
uint32_t *bg, uint32_t *fg, \
struct QDict **palette) { \
uint##bpp##_t *data; \
uint##bpp##_t c0, c1, ci; \
int i, n0, n1; \
\
data = (uint##bpp##_t *)vs->tight.buffer; \
\
c0 = data[0]; \
i = 1; \
while (i < count && data[i] == c0) \
i++; \
if (i >= count) { \
*bg = *fg = c0; \
return 1; \
} \
\
if (max < 2) { \
return 0; \
} \
\
n0 = i; \
c1 = data[i]; \
n1 = 0; \
for (i++; i < count; i++) { \
ci = data[i]; \
if (ci == c0) { \
n0++; \
} else if (ci == c1) { \
n1++; \
} else \
break; \
} \
if (i >= count) { \
if (n0 > n1) { \
*bg = (uint32_t)c0; \
*fg = (uint32_t)c1; \
} else { \
*bg = (uint32_t)c1; \
*fg = (uint32_t)c0; \
} \
return 2; \
} \
\
if (max == 2) { \
return 0; \
} \
\
*palette = qdict_new(); \
tight_palette_insert(*palette, c0, bpp, max); \
tight_palette_insert(*palette, c1, bpp, max); \
tight_palette_insert(*palette, ci, bpp, max); \
\
for (i++; i < count; i++) { \
if (data[i] == ci) { \
continue; \
} else { \
if (!tight_palette_insert(*palette, (uint32_t)ci, \
bpp, max)) { \
return 0; \
} \
ci = data[i]; \
} \
} \
\
return qdict_size(*palette); \
}
DEFINE_FILL_PALETTE_FUNCTION(8)
DEFINE_FILL_PALETTE_FUNCTION(16)
DEFINE_FILL_PALETTE_FUNCTION(32)
static int tight_fill_palette(VncState *vs, int x, int y,
size_t count, uint32_t *bg, uint32_t *fg,
struct QDict **palette)
{
int max;
max = count / tight_conf[vs->tight_compression].idx_max_colors_divisor;
if (max < 2 &&
count >= tight_conf[vs->tight_compression].mono_min_rect_size) {
max = 2;
}
if (max >= 256) {
max = 256;
}
switch(vs->clientds.pf.bytes_per_pixel) {
case 4:
return tight_fill_palette32(vs, x, y, max, count, bg, fg, palette);
case 2:
return tight_fill_palette16(vs, x, y, max, count, bg, fg, palette);
default:
max = 2;
return tight_fill_palette8(vs, x, y, max, count, bg, fg, palette);
}
return 0;
}
/* Callback to dump a palette with qdict_iter
static void print_palette(const char *key, QObject *obj, void *opaque)
{
uint8_t idx = qint_get_int(qobject_to_qint(obj));
uint32_t rgb = tight_palette_buf2rgb(32, (uint8_t *)key);
fprintf(stderr, "%.2x ", (unsigned char)*key);
while (*key++)
fprintf(stderr, "%.2x ", (unsigned char)*key);
fprintf(stderr, ": idx: %x rgb: %x\n", idx, rgb);
}
*/
/*
* Converting truecolor samples into palette indices.
*/
#define DEFINE_IDX_ENCODE_FUNCTION(bpp) \
\
static void \
tight_encode_indexed_rect##bpp(uint8_t *buf, int count, \
struct QDict *palette) { \
uint##bpp##_t *src; \
uint##bpp##_t rgb; \
uint8_t key[6]; \
int i, rep; \
uint8_t idx; \
\
src = (uint##bpp##_t *) buf; \
\
for (i = 0; i < count; i++) { \
rgb = *src++; \
rep = 0; \
while (i < count && *src == rgb) { \
rep++, src++, i++; \
} \
tight_palette_rgb2buf(rgb, bpp, key); \
if (!qdict_haskey(palette, (char *)key)) { \
/* \
* Should never happen, but don't break everything \
* if it does, use the first color instead \
*/ \
idx = 0; \
} else { \
idx = qdict_get_int(palette, (char *)key); \
} \
while (rep >= 0) { \
*buf++ = idx; \
rep--; \
} \
} \
}
DEFINE_IDX_ENCODE_FUNCTION(16)
DEFINE_IDX_ENCODE_FUNCTION(32)
#define DEFINE_MONO_ENCODE_FUNCTION(bpp) \
\
static void \
tight_encode_mono_rect##bpp(uint8_t *buf, int w, int h, \
uint##bpp##_t bg, uint##bpp##_t fg) { \
uint##bpp##_t *ptr; \
unsigned int value, mask; \
int aligned_width; \
int x, y, bg_bits; \
\
ptr = (uint##bpp##_t *) buf; \
aligned_width = w - w % 8; \
\
for (y = 0; y < h; y++) { \
for (x = 0; x < aligned_width; x += 8) { \
for (bg_bits = 0; bg_bits < 8; bg_bits++) { \
if (*ptr++ != bg) { \
break; \
} \
} \
if (bg_bits == 8) { \
*buf++ = 0; \
continue; \
} \
mask = 0x80 >> bg_bits; \
value = mask; \
for (bg_bits++; bg_bits < 8; bg_bits++) { \
mask >>= 1; \
if (*ptr++ != bg) { \
value |= mask; \
} \
} \
*buf++ = (uint8_t)value; \
} \
\
mask = 0x80; \
value = 0; \
if (x >= w) { \
continue; \
} \
\
for (; x < w; x++) { \
if (*ptr++ != bg) { \
value |= mask; \
} \
mask >>= 1; \
} \
*buf++ = (uint8_t)value; \
} \
}
DEFINE_MONO_ENCODE_FUNCTION(8)
DEFINE_MONO_ENCODE_FUNCTION(16)
DEFINE_MONO_ENCODE_FUNCTION(32)
/*
* Check if a rectangle is all of the same color. If needSameColor is
* set to non-zero, then also check that its color equals to the
* *colorPtr value. The result is 1 if the test is successfull, and in
* that case new color will be stored in *colorPtr.
*/
#define DEFINE_CHECK_SOLID_FUNCTION(bpp) \
\
static bool \
check_solid_tile##bpp(VncState *vs, int x, int y, int w, int h, \
uint32_t* color, bool samecolor) \
{ \
VncDisplay *vd = vs->vd; \
uint##bpp##_t *fbptr; \
uint##bpp##_t c; \
int dx, dy; \
\
fbptr = (uint##bpp##_t *) \
(vd->server->data + y * ds_get_linesize(vs->ds) + \
x * ds_get_bytes_per_pixel(vs->ds)); \
\
c = *fbptr; \
if (samecolor && (uint32_t)c != *color) { \
return false; \
} \
\
for (dy = 0; dy < h; dy++) { \
for (dx = 0; dx < w; dx++) { \
if (c != fbptr[dx]) { \
return false; \
} \
} \
fbptr = (uint##bpp##_t *) \
((uint8_t *)fbptr + ds_get_linesize(vs->ds)); \
} \
\
*color = (uint32_t)c; \
return true; \
}
DEFINE_CHECK_SOLID_FUNCTION(32)
DEFINE_CHECK_SOLID_FUNCTION(16)
DEFINE_CHECK_SOLID_FUNCTION(8)
static bool check_solid_tile(VncState *vs, int x, int y, int w, int h,
uint32_t* color, bool samecolor)
{
VncDisplay *vd = vs->vd;
switch(vd->server->pf.bytes_per_pixel) {
case 4:
return check_solid_tile32(vs, x, y, w, h, color, samecolor);
case 2:
return check_solid_tile16(vs, x, y, w, h, color, samecolor);
default:
return check_solid_tile8(vs, x, y, w, h, color, samecolor);
}
}
static void find_best_solid_area(VncState *vs, int x, int y, int w, int h,
uint32_t color, int *w_ptr, int *h_ptr)
{
int dx, dy, dw, dh;
int w_prev;
int w_best = 0, h_best = 0;
w_prev = w;
for (dy = y; dy < y + h; dy += VNC_TIGHT_MAX_SPLIT_TILE_SIZE) {
dh = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, y + h - dy);
dw = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, w_prev);
if (!check_solid_tile(vs, x, dy, dw, dh, &color, true)) {
break;
}
for (dx = x + dw; dx < x + w_prev;) {
dw = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, x + w_prev - dx);
if (!check_solid_tile(vs, dx, dy, dw, dh, &color, true)) {
break;
}
dx += dw;
}
w_prev = dx - x;
if (w_prev * (dy + dh - y) > w_best * h_best) {
w_best = w_prev;
h_best = dy + dh - y;
}
}
*w_ptr = w_best;
*h_ptr = h_best;
}
static void extend_solid_area(VncState *vs, int x, int y, int w, int h,
uint32_t color, int *x_ptr, int *y_ptr,
int *w_ptr, int *h_ptr)
{
int cx, cy;
/* Try to extend the area upwards. */
for ( cy = *y_ptr - 1;
cy >= y && check_solid_tile(vs, *x_ptr, cy, *w_ptr, 1, &color, true);
cy-- );
*h_ptr += *y_ptr - (cy + 1);
*y_ptr = cy + 1;
/* ... downwards. */
for ( cy = *y_ptr + *h_ptr;
cy < y + h &&
check_solid_tile(vs, *x_ptr, cy, *w_ptr, 1, &color, true);
cy++ );
*h_ptr += cy - (*y_ptr + *h_ptr);
/* ... to the left. */
for ( cx = *x_ptr - 1;
cx >= x && check_solid_tile(vs, cx, *y_ptr, 1, *h_ptr, &color, true);
cx-- );
*w_ptr += *x_ptr - (cx + 1);
*x_ptr = cx + 1;
/* ... to the right. */
for ( cx = *x_ptr + *w_ptr;
cx < x + w &&
check_solid_tile(vs, cx, *y_ptr, 1, *h_ptr, &color, true);
cx++ );
*w_ptr += cx - (*x_ptr + *w_ptr);
}
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, uint8_t *buf, size_t count, size_t *ret)
{
uint32_t *buf32;
uint32_t pix;
int rshift, gshift, bshift;
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;
}
if (ret) {
*ret = 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, vs->tight.buffer, w * h, &vs->tight.offset);
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 int send_solid_rect(VncState *vs)
{
size_t bytes;
vnc_write_u8(vs, VNC_TIGHT_FILL << 4); /* no flushing, no filter */
if (vs->tight_pixel24) {
tight_pack24(vs, vs->tight.buffer, 1, &vs->tight.offset);
bytes = 3;
} else {
bytes = vs->clientds.pf.bytes_per_pixel;
}
vnc_write(vs, vs->tight.buffer, bytes);
return 1;
}
static int send_mono_rect(VncState *vs, int w, int h, uint32_t bg, uint32_t fg)
{
size_t bytes;
int stream = 1;
int level = tight_conf[vs->tight_compression].mono_zlib_level;
bytes = ((w + 7) / 8) * h;
vnc_write_u8(vs, (stream | VNC_TIGHT_EXPLICIT_FILTER) << 4);
vnc_write_u8(vs, VNC_TIGHT_FILTER_PALETTE);
vnc_write_u8(vs, 1);
switch(vs->clientds.pf.bytes_per_pixel) {
case 4:
{
uint32_t buf[2] = {bg, fg};
size_t ret = sizeof (buf);
if (vs->tight_pixel24) {
tight_pack24(vs, (unsigned char*)buf, 2, &ret);
}
vnc_write(vs, buf, ret);
tight_encode_mono_rect32(vs->tight.buffer, w, h, bg, fg);
break;
}
case 2:
vnc_write(vs, &bg, 2);
vnc_write(vs, &fg, 2);
tight_encode_mono_rect16(vs->tight.buffer, w, h, bg, fg);
break;
default:
vnc_write_u8(vs, bg);
vnc_write_u8(vs, fg);
tight_encode_mono_rect8(vs->tight.buffer, w, h, bg, fg);
break;
}
vs->tight.offset = bytes;
bytes = tight_compress_data(vs, stream, bytes, level, Z_DEFAULT_STRATEGY);
return (bytes >= 0);
}
struct palette_cb_priv {
VncState *vs;
uint8_t *header;
};
static void write_palette(const char *key, QObject *obj, void *opaque)
{
struct palette_cb_priv *priv = opaque;
VncState *vs = priv->vs;
uint32_t bytes = vs->clientds.pf.bytes_per_pixel;
uint8_t idx = qint_get_int(qobject_to_qint(obj));
if (bytes == 4) {
uint32_t color = tight_palette_buf2rgb(32, (uint8_t *)key);
((uint32_t*)priv->header)[idx] = color;
} else {
uint16_t color = tight_palette_buf2rgb(16, (uint8_t *)key);
((uint16_t*)priv->header)[idx] = color;
}
}
static int send_palette_rect(VncState *vs, int w, int h, struct QDict *palette)
{
int stream = 2;
int level = tight_conf[vs->tight_compression].idx_zlib_level;
int colors;
size_t bytes;
colors = qdict_size(palette);
vnc_write_u8(vs, (stream | VNC_TIGHT_EXPLICIT_FILTER) << 4);
vnc_write_u8(vs, VNC_TIGHT_FILTER_PALETTE);
vnc_write_u8(vs, colors - 1);
switch(vs->clientds.pf.bytes_per_pixel) {
case 4:
{
size_t old_offset, offset;
uint32_t header[qdict_size(palette)];
struct palette_cb_priv priv = { vs, (uint8_t *)header };
old_offset = vs->output.offset;
qdict_iter(palette, write_palette, &priv);
vnc_write(vs, header, sizeof(header));
if (vs->tight_pixel24) {
tight_pack24(vs, vs->output.buffer + old_offset, colors, &offset);
vs->output.offset = old_offset + offset;
}
tight_encode_indexed_rect32(vs->tight.buffer, w * h, palette);
break;
}
case 2:
{
uint16_t header[qdict_size(palette)];
struct palette_cb_priv priv = { vs, (uint8_t *)header };
qdict_iter(palette, write_palette, &priv);
vnc_write(vs, header, sizeof(header));
tight_encode_indexed_rect16(vs->tight.buffer, w * h, palette);
break;
}
default:
return -1; /* No palette for 8bits colors */
break;
}
bytes = w * h;
vs->tight.offset = bytes;
bytes = tight_compress_data(vs, stream, bytes,
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)
{
struct QDict *palette = NULL;
uint32_t bg = 0, fg = 0;
int colors;
int ret = 0;
vnc_framebuffer_update(vs, x, y, w, h, VNC_ENCODING_TIGHT);
vnc_tight_start(vs);
vnc_raw_send_framebuffer_update(vs, x, y, w, h);
vnc_tight_stop(vs);
colors = tight_fill_palette(vs, x, y, w * h, &fg, &bg, &palette);
if (colors == 0) {
ret = send_full_color_rect(vs, w, h);
} else if (colors == 1) {
ret = send_solid_rect(vs);
} else if (colors == 2) {
ret = send_mono_rect(vs, w, h, bg, fg);
} else if (colors <= 256) {
ret = send_palette_rect(vs, w, h, palette);
}
QDECREF(palette);
return ret;
}
static int send_sub_rect_solid(VncState *vs, int x, int y, int w, int h)
{
vnc_framebuffer_update(vs, x, y, w, h, VNC_ENCODING_TIGHT);
vnc_tight_start(vs);
vnc_raw_send_framebuffer_update(vs, x, y, w, h);
vnc_tight_stop(vs);
return send_solid_rect(vs);
}
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;
}
static int find_large_solid_color_rect(VncState *vs, int x, int y,
int w, int h, int max_rows)
{
int dx, dy, dw, dh;
int n = 0;
/* Try to find large solid-color areas and send them separately. */
for (dy = y; dy < y + h; dy += VNC_TIGHT_MAX_SPLIT_TILE_SIZE) {
/* If a rectangle becomes too large, send its upper part now. */
if (dy - y >= max_rows) {
n += send_rect_simple(vs, x, y, w, max_rows);
y += max_rows;
h -= max_rows;
}
dh = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, (y + h - dy));
for (dx = x; dx < x + w; dx += VNC_TIGHT_MAX_SPLIT_TILE_SIZE) {
uint32_t color_value;
int x_best, y_best, w_best, h_best;
dw = MIN(VNC_TIGHT_MAX_SPLIT_TILE_SIZE, (x + w - dx));
if (!check_solid_tile(vs, dx, dy, dw, dh, &color_value, false)) {
continue ;
}
/* Get dimensions of solid-color area. */
find_best_solid_area(vs, dx, dy, w - (dx - x), h - (dy - y),
color_value, &w_best, &h_best);
/* Make sure a solid rectangle is large enough
(or the whole rectangle is of the same color). */
if (w_best * h_best != w * h &&
w_best * h_best < VNC_TIGHT_MIN_SOLID_SUBRECT_SIZE) {
continue;
}
/* Try to extend solid rectangle to maximum size. */
x_best = dx; y_best = dy;
extend_solid_area(vs, x, y, w, h, color_value,
&x_best, &y_best, &w_best, &h_best);
/* Send rectangles at top and left to solid-color area. */
if (y_best != y) {
n += send_rect_simple(vs, x, y, w, y_best-y);
}
if (x_best != x) {
n += vnc_tight_send_framebuffer_update(vs, x, y_best,
x_best-x, h_best);
}
/* Send solid-color rectangle. */
n += send_sub_rect_solid(vs, x_best, y_best, w_best, h_best);
/* Send remaining rectangles (at right and bottom). */
if (x_best + w_best != x + w) {
n += vnc_tight_send_framebuffer_update(vs, x_best+w_best,
y_best,
w-(x_best-x)-w_best,
h_best);
}
if (y_best + h_best != y + h) {
n += vnc_tight_send_framebuffer_update(vs, x, y_best+h_best,
w, h-(y_best-y)-h_best);
}
/* Return after all recursive calls are done. */
return n;
}
}
return n + send_rect_simple(vs, x, y, w, h);
}
int vnc_tight_send_framebuffer_update(VncState *vs, int x, int y,
int w, int h)
{
int max_rows;
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;
}
if (w * h < VNC_TIGHT_MIN_SPLIT_RECT_SIZE)
return send_rect_simple(vs, x, y, w, h);
/* Calculate maximum number of rows in one non-solid rectangle. */
max_rows = tight_conf[vs->tight_compression].max_rect_size;
max_rows /= MIN(tight_conf[vs->tight_compression].max_rect_width, w);
return find_large_solid_color_rect(vs, x, y, w, h, max_rows);
}
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);
}