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authortoma <toma@283d02a7-25f6-0310-bc7c-ecb5cbfe19da>2009-11-25 17:56:58 +0000
committertoma <toma@283d02a7-25f6-0310-bc7c-ecb5cbfe19da>2009-11-25 17:56:58 +0000
commitbcb704366cb5e333a626c18c308c7e0448a8e69f (patch)
treef0d6ab7d78ecdd9207cf46536376b44b91a1ca71 /kopete/libkopete/avdevice/sonix_compress.cpp
downloadtdenetwork-bcb704366cb5e333a626c18c308c7e0448a8e69f.tar.gz
tdenetwork-bcb704366cb5e333a626c18c308c7e0448a8e69f.zip
Copy the KDE 3.5 branch to branches/trinity for new KDE 3.5 features.
BUG:215923 git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdenetwork@1054174 283d02a7-25f6-0310-bc7c-ecb5cbfe19da
Diffstat (limited to 'kopete/libkopete/avdevice/sonix_compress.cpp')
-rw-r--r--kopete/libkopete/avdevice/sonix_compress.cpp180
1 files changed, 180 insertions, 0 deletions
diff --git a/kopete/libkopete/avdevice/sonix_compress.cpp b/kopete/libkopete/avdevice/sonix_compress.cpp
new file mode 100644
index 00000000..400635c4
--- /dev/null
+++ b/kopete/libkopete/avdevice/sonix_compress.cpp
@@ -0,0 +1,180 @@
+#include "sonix_compress.h"
+
+#define CLAMP(x) ((x)<0?0:((x)>255)?255:(x))
+
+typedef struct {
+ int is_abs;
+ int len;
+ int val;
+ int unk;
+} code_table_t;
+
+
+/* local storage */
+static code_table_t table[256];
+static int init_done = 0;
+
+/* global variable */
+int sonix_unknown = 0;
+
+/*
+ sonix_decompress_init
+ =====================
+ pre-calculates a locally stored table for efficient huffman-decoding.
+
+ Each entry at index x in the table represents the codeword
+ present at the MSB of byte x.
+
+*/
+void sonix_decompress_init(void)
+{
+ int i;
+ int is_abs, val, len, unk;
+
+ for (i = 0; i < 256; i++) {
+ is_abs = 0;
+ val = 0;
+ len = 0;
+ unk = 0;
+ if ((i & 0x80) == 0) {
+ /* code 0 */
+ val = 0;
+ len = 1;
+ }
+ else if ((i & 0xE0) == 0x80) {
+ /* code 100 */
+ val = +4;
+ len = 3;
+ }
+ else if ((i & 0xE0) == 0xA0) {
+ /* code 101 */
+ val = -4;
+ len = 3;
+ }
+ else if ((i & 0xF0) == 0xD0) {
+ /* code 1101 */
+ val = +11;
+ len = 4;
+ }
+ else if ((i & 0xF0) == 0xF0) {
+ /* code 1111 */
+ val = -11;
+ len = 4;
+ }
+ else if ((i & 0xF8) == 0xC8) {
+ /* code 11001 */
+ val = +20;
+ len = 5;
+ }
+ else if ((i & 0xFC) == 0xC0) {
+ /* code 110000 */
+ val = -20;
+ len = 6;
+ }
+ else if ((i & 0xFC) == 0xC4) {
+ /* code 110001xx: unknown */
+ val = 0;
+ len = 8;
+ unk = 1;
+ }
+ else if ((i & 0xF0) == 0xE0) {
+ /* code 1110xxxx */
+ is_abs = 1;
+ val = (i & 0x0F) << 4;
+ len = 8;
+ }
+ table[i].is_abs = is_abs;
+ table[i].val = val;
+ table[i].len = len;
+ table[i].unk = unk;
+ }
+
+ sonix_unknown = 0;
+ init_done = 1;
+}
+
+
+/*
+ sonix_decompress
+ ================
+ decompresses an image encoded by a SN9C101 camera controller chip.
+
+ IN width
+ height
+ inp pointer to compressed frame (with header already stripped)
+ OUT outp pointer to decompressed frame
+
+ Returns 0 if the operation was successful.
+ Returns <0 if operation failed.
+
+*/
+int sonix_decompress(int width, int height, unsigned char *inp, unsigned char *outp)
+{
+ int row, col;
+ int val;
+ int bitpos;
+ unsigned char code;
+ unsigned char *addr;
+
+ if (!init_done) {
+ /* do sonix_decompress_init first! */
+ return -1;
+ }
+
+ bitpos = 0;
+ for (row = 0; row < height; row++) {
+
+ col = 0;
+
+ /* first two pixels in first two rows are stored as raw 8-bit */
+ if (row < 2) {
+ addr = inp + (bitpos >> 3);
+ code = (addr[0] << (bitpos & 7)) | (addr[1] >> (8 - (bitpos & 7)));
+ bitpos += 8;
+ *outp++ = code;
+
+ addr = inp + (bitpos >> 3);
+ code = (addr[0] << (bitpos & 7)) | (addr[1] >> (8 - (bitpos & 7)));
+ bitpos += 8;
+ *outp++ = code;
+
+ col += 2;
+ }
+
+ while (col < width) {
+ /* get bitcode from bitstream */
+ addr = inp + (bitpos >> 3);
+ code = (addr[0] << (bitpos & 7)) | (addr[1] >> (8 - (bitpos & 7)));
+
+ /* update bit position */
+ bitpos += table[code].len;
+
+ /* update code statistics */
+ sonix_unknown += table[code].unk;
+
+ /* calculate pixel value */
+ val = table[code].val;
+ if (!table[code].is_abs) {
+ /* value is relative to top and left pixel */
+ if (col < 2) {
+ /* left column: relative to top pixel */
+ val += outp[-2*width];
+ }
+ else if (row < 2) {
+ /* top row: relative to left pixel */
+ val += outp[-2];
+ }
+ else {
+ /* main area: average of left pixel and top pixel */
+ val += (outp[-2] + outp[-2*width]) / 2;
+ }
+ }
+
+ /* store pixel */
+ *outp++ = CLAMP(val);
+ col++;
+ }
+ }
+
+ return 0;
+}