Add palette tight encoding. Palette encoding will try to count the number
of colors for a given rectangle, and if this number is low enough
(< 256) it will send the palette + the rectangle with indexed colors.
Signed-off-by: Corentin Chary <corenti...@iksaif.net>
---
vnc-encoding-tight.c | 430 ++++++++++++++++++++++++++++++++++++++++++++++++--
1 files changed, 418 insertions(+), 12 deletions(-)
diff --git a/vnc-encoding-tight.c b/vnc-encoding-tight.c
index 44984f9..b836569 100644
--- a/vnc-encoding-tight.c
+++ b/vnc-encoding-tight.c
@@ -27,6 +27,8 @@
#include <stdbool.h>
+#include "qdict.h"
+#include "qint.h"
#include "vnc.h"
#include "vnc-encoding-tight.h"
@@ -55,6 +57,279 @@ static const struct {
};
/*
+ * 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); \
+ \
+ 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 rep = 0; \
+ uint8_t idx; \
+ \
+ src = (uint##bpp##_t *) buf; \
+ \
+ count -= 1; \
+ while (count--) { \
+ rgb = *src++; \
+ rep = 0; \
+ while (count && *src == rgb) { \
+ rep++, src++, count--; \
+ } \
+ 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
@@ -282,14 +557,12 @@ static int tight_compress_data(VncState *vs, int
stream_id, size_t bytes,
/*
* Subencoding implementations.
*/
-static void tight_pack24(VncState *vs, size_t count)
+static void tight_pack24(VncState *vs, uint8_t *buf, size_t count, size_t *ret)
{
- unsigned char *buf;
uint32_t *buf32;
uint32_t pix;
int rshift, gshift, bshift;
- buf = vs->tight.buffer;
buf32 = (uint32_t *)buf;
if ((vs->clientds.flags & QEMU_BIG_ENDIAN_FLAG) ==
@@ -303,7 +576,8 @@ static void tight_pack24(VncState *vs, size_t count)
bshift = 24 - vs->clientds.pf.bshift;
}
- vs->tight.offset = count * 3;
+ if (ret)
+ *ret = count * 3;
while (count--) {
pix = *buf32++;
@@ -321,7 +595,7 @@ static int send_full_color_rect(VncState *vs, int w, int h)
vnc_write_u8(vs, stream << 4); /* no flushing, no filter */
if (vs->tight_pixel24) {
- tight_pack24(vs, w * h);
+ tight_pack24(vs, vs->tight.buffer, w * h, &vs->tight.offset);
bytes = 3;
} else {
bytes = vs->clientds.pf.bytes_per_pixel;
@@ -341,7 +615,7 @@ static int send_solid_rect(VncState *vs)
vnc_write_u8(vs, VNC_TIGHT_FILL << 4); /* no flushing, no filter */
if (vs->tight_pixel24) {
- tight_pack24(vs, 1);
+ tight_pack24(vs, vs->tight.buffer, 1, &vs->tight.offset);
bytes = 3;
} else {
bytes = vs->clientds.pf.bytes_per_pixel;
@@ -351,6 +625,126 @@ static int send_solid_rect(VncState *vs)
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);
@@ -369,18 +763,30 @@ static void vnc_tight_stop(VncState *vs)
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);
- /*
- * Convert pixels and store them in vs->tight
- * We will probably rework that later, probably
- * when adding other sub-encodings
- */
vnc_tight_start(vs);
vnc_raw_send_framebuffer_update(vs, x, y, w, h);
vnc_tight_stop(vs);
- return send_full_color_rect(vs, w, h);
+ 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)
--
1.7.0.2
