vnc: add a non-adaptive option
This option allow to disable adaptive behaviors in some encodings.
Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/qemu-options.hx b/qemu-options.hx
index 945edf3..badb730 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -913,6 +913,15 @@
depending on its encoding settings. Enabling this option can save
a lot of bandwidth at the expense of quality.
+@item non-adaptive
+
+Disable adaptive encodings. Adaptive encodings are enabled by default.
+An adaptive encoding will try to detect frequently updated screen regions,
+and send updates in these regions using a lossy encoding (like JPEG).
+This can be really helpfull to save bandwidth when playing videos. Disabling
+adaptive encodings allow to restore the original static behavior of encodings
+like Tight.
+
@end table
ETEXI
diff --git a/ui/vnc-enc-tight.c b/ui/vnc-enc-tight.c
index 82c1e96..5933394 100644
--- a/ui/vnc-enc-tight.c
+++ b/ui/vnc-enc-tight.c
@@ -1546,7 +1546,7 @@
vnc_tight_stop(vs);
#ifdef CONFIG_VNC_JPEG
- if (vs->tight.quality != (uint8_t)-1) {
+ if (!vs->vd->non_adaptive && vs->tight.quality != (uint8_t)-1) {
double freq = vnc_update_freq(vs, x, y, w, h);
if (freq < tight_jpeg_conf[vs->tight.quality].jpeg_freq_min) {
diff --git a/ui/vnc.c b/ui/vnc.c
index 86c23207..626b430 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -2387,10 +2387,12 @@
VncState *vs;
int has_dirty = 0;
- struct timeval tv;
+ struct timeval tv = { 0, 0 };
- gettimeofday(&tv, NULL);
- has_dirty = vnc_update_stats(vd, &tv);
+ if (!vd->non_adaptive) {
+ gettimeofday(&tv, NULL);
+ has_dirty = vnc_update_stats(vd, &tv);
+ }
/*
* Walk through the guest dirty map.
@@ -2419,7 +2421,8 @@
if (memcmp(server_ptr, guest_ptr, cmp_bytes) == 0)
continue;
memcpy(server_ptr, guest_ptr, cmp_bytes);
- vnc_rect_updated(vd, x, y, &tv);
+ if (!vd->non_adaptive)
+ vnc_rect_updated(vd, x, y, &tv);
QTAILQ_FOREACH(vs, &vd->clients, next) {
set_bit((x / 16), vs->dirty[y]);
}
@@ -2754,6 +2757,8 @@
#endif
} else if (strncmp(options, "lossy", 5) == 0) {
vs->lossy = true;
+ } else if (strncmp(options, "non-adapative", 13) == 0) {
+ vs->non_adaptive = true;
}
}
diff --git a/ui/vnc.h b/ui/vnc.h
index 98a1885..8a1e7b9 100644
--- a/ui/vnc.h
+++ b/ui/vnc.h
@@ -144,6 +144,7 @@
time_t expires;
int auth;
bool lossy;
+ bool non_adaptive;
#ifdef CONFIG_VNC_TLS
int subauth; /* Used by VeNCrypt */
VncDisplayTLS tls;