vnc: add support for tight fill encoding

Fill encoding detects rectangles using only one color and send only
one pixel value.

Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Corentin Chary 2010-05-19 09:24:11 +02:00 committed by Anthony Liguori
parent 380282b07d
commit b4bea3f2b8

View File

@ -55,6 +55,139 @@ static const struct {
{ 65536, 2048, 32, 8192, 9, 9, 9, 6, 200, 500, 96, 80, 200, 500 }
};
/*
* 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)
{
@ -104,7 +237,7 @@ static void tight_send_compact_size(VncState *vs, size_t len)
buf[bytes++] = (len >> 14) & 0xFF;
}
}
for(lpc = 0; lpc < bytes; lpc++) {
for (lpc = 0; lpc < bytes; lpc++) {
vnc_write_u8(vs, buf[lpc]);
}
}
@ -207,6 +340,23 @@ static int send_full_color_rect(VncState *vs, int w, int h)
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, 1);
bytes = 3;
} else {
bytes = vs->clientds.pf.bytes_per_pixel;
}
vnc_write(vs, vs->tight.buffer, bytes);
return 1;
}
static void vnc_tight_start(VncState *vs)
{
buffer_reset(&vs->tight);
@ -239,6 +389,17 @@ static int send_sub_rect(VncState *vs, int x, int y, int w, int h)
return send_full_color_rect(vs, w, h);
}
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;
@ -268,9 +429,93 @@ static int send_rect_simple(VncState *vs, int x, int y, int w, int 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;
@ -278,7 +523,15 @@ int vnc_tight_send_framebuffer_update(VncState *vs, int x, int y,
vs->tight_pixel24 = false;
}
return send_rect_simple(vs, x, y, w, h);
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)