Disable png filters for lower compression levels. This should lower the CPU consumption and reduce encoding time.
This isn't in tight_conf because: * tight_conf structure must not change, because it's shared with other tight implementations (libvncserver, etc..). * it'd exceed the 80 col limit. * PNG_ macros are only defined if CONFIG_VNC_PNG is defined Signed-off-by: Corentin Chary <corenti...@iksaif.net> --- ui/vnc-enc-tight.c | 19 ++++++++++++++++++- 1 files changed, 18 insertions(+), 1 deletions(-) diff --git a/ui/vnc-enc-tight.c b/ui/vnc-enc-tight.c index 007d88f..9e1f214 100644 --- a/ui/vnc-enc-tight.c +++ b/ui/vnc-enc-tight.c @@ -69,6 +69,21 @@ static const struct { }; #ifdef CONFIG_VNC_PNG +static const struct { + int png_zlib_level, png_filters; +} tight_png_conf[] = { + { 0, PNG_NO_FILTERS }, + { 1, PNG_NO_FILTERS }, + { 2, PNG_NO_FILTERS }, + { 3, PNG_NO_FILTERS }, + { 4, PNG_NO_FILTERS }, + { 5, PNG_ALL_FILTERS }, + { 6, PNG_ALL_FILTERS }, + { 7, PNG_ALL_FILTERS }, + { 8, PNG_ALL_FILTERS }, + { 9, PNG_ALL_FILTERS }, +}; + static int send_png_rect(VncState *vs, int x, int y, int w, int h, QDict *palette); @@ -1424,7 +1439,8 @@ static int send_png_rect(VncState *vs, int x, int y, int w, int h, png_infop info_ptr; png_colorp png_palette = NULL; size_t offset; - int level = tight_conf[vs->tight_compression].raw_zlib_level; + int level = tight_png_conf[vs->tight_compression].png_zlib_level; + int filters = tight_png_conf[vs->tight_compression].png_filters; uint8_t *buf; int dy; @@ -1443,6 +1459,7 @@ static int send_png_rect(VncState *vs, int x, int y, int w, int h, png_set_write_fn(png_ptr, (void *) vs, png_write_data, png_flush_data); png_set_compression_level(png_ptr, level); + png_set_filter(png_ptr, PNG_FILTER_TYPE_DEFAULT, filters); if (palette) { color_type = PNG_COLOR_TYPE_PALETTE; -- 1.7.1