The lossless option can be used to force lossless compression by disabling all lossy encodings like gradient or jpeg.
Signed-off-by: Corentin Chary <corenti...@iksaif.net> --- qemu-options.hx | 5 +++++ vnc-encoding-tight.c | 4 ++++ vnc.c | 2 ++ vnc.h | 2 ++ 4 files changed, 13 insertions(+), 0 deletions(-) diff --git a/qemu-options.hx b/qemu-options.hx index a6928b7..81fd737 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -828,6 +828,11 @@ empty, with a @code{deny} policy. Thus no one will be allowed to use the VNC server until the ACLs have been loaded. This can be achieved using the @code{acl} monitor command. +...@item lossless + +Turn off all lossy compression methods (gradient, JPEG, ...). If this +option is set, VNC client will only receive lossless framebuffer updates. + @end table ETEXI diff --git a/vnc-encoding-tight.c b/vnc-encoding-tight.c index 495745e..51bb707 100644 --- a/vnc-encoding-tight.c +++ b/vnc-encoding-tight.c @@ -230,6 +230,10 @@ tight_detect_smooth_image(VncState *vs, int w, int h) int compression = vs->tight_compression; int quality = vs->tight_quality; + if (vs->vd->lossless) { + return 0; + } + if (ds_get_bytes_per_pixel(vs->ds) == 1 || vs->clientds.pf.bytes_per_pixel == 1 || w < VNC_TIGHT_DETECT_MIN_WIDTH || h < VNC_TIGHT_DETECT_MIN_HEIGHT) { diff --git a/vnc.c b/vnc.c index 9cf38d1..e3ef315 100644 --- a/vnc.c +++ b/vnc.c @@ -2482,6 +2482,8 @@ int vnc_display_open(DisplayState *ds, const char *display) #endif } else if (strncmp(options, "acl", 3) == 0) { acl = 1; + } else if (strncmp(options, "lossless", 8) == 0) { + vs->lossless = true; } } diff --git a/vnc.h b/vnc.h index 2a9024d..cca1946 100644 --- a/vnc.h +++ b/vnc.h @@ -33,6 +33,7 @@ #include "monitor.h" #include "audio/audio.h" #include <zlib.h> +#include <stdbool.h> #include "keymaps.h" @@ -111,6 +112,7 @@ struct VncDisplay char *display; char *password; int auth; + bool lossless; #ifdef CONFIG_VNC_TLS int subauth; /* Used by VeNCrypt */ VncDisplayTLS tls; -- 1.7.1